Dissertations / Theses: 'MIP [Moleculary imprinted polymer]'

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Wagner, Sabine. "Sensory molecularly imprinted polymer (MIP) coatings for nanoparticle- and fiber optic-based assays." Doctoral thesis, Humboldt-Universität zu Berlin, 2019. http://dx.doi.org/10.18452/19808.

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Für den Nachweis dieser Schadstoffe in niedrigen Konzentrationsbereichen sind schnelle und empfindliche Analysemethoden erforderlich. Molekular geprägte Polymere (MIPs) wurden als synthetische Materialien entwickelt, um die molekulare Erkennung von natürlichen Rezeptoren nachzuahmen, aufgrund ihrer Fähigkeit, selektiv eine Vielzahl von Analyten zu erkennen, ihre Stabilität und ihrer einfachen Herstellung. Sie sind zunehmend in der chemischen Sensorik als Rezeptormaterial für den Nachweis bestimmter Analyten bei niedrigen Konzentrationen zu finden, insbesondere in Kombination mit Fluoreszenz aufgrund dessen hoher Empfindlichkeit. Ziel dieser Arbeit war die Entwicklung von optischen Sensormaterialien unter Verwendung von MIPs als Erkennungselemente im Zusammenhang mit Fluoreszenz zum sensitiven Nachweis von Herbiziden und Antibiotika in Wasser- und Lebensmittelproben and deren Kombination mit verschiedenen Vorrichtungsformaten für die zukünftige Detektion einer breiten Palette von wichtigen Analyten.
For the detection of these contaminants in low concentration ranges fast and sensitive analytical tools are required. Molecularly imprinted polymers (MIPs) have been used as synthetic materials mimicking molecular recognition by natural receptors due to their ability to recognize selectively a wide range of analytes, their stability and ease of synthesis. They have gained more and more attention in chemical sensing as receptor material for the detection of suitable groups of analytes at low concentrations especially in combination with fluorescence due to the latter’s high sensitivity. This work aimed the development of optical sensor materials using MIPs as recognition elements connected with fluorescence for the sensitive detection of herbicides and antibiotics in water and food samples and their combination with various device formats for the future detection of a wide range of analytes.

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Tsai, Mei-Hsuan. "Boron containing molecular imprinted polymer (MIP) templates from symmetric and asymmetric diboration of olefins and other boron containing functional polymers." Thesis, University of Cambridge, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.608235.

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Bitar, Manal. "Design d'un iprodione-MIP (molecularly imprinted polymer) : application à la pré-concentration des fongicides dans le vin." Thesis, Dijon, 2014. http://www.theses.fr/2014DIJOS066/document.

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Les travaux de thèse ont porté sur la synthèse d’un MIP (polymère à empreintes moléculaires) spécifique d’un fongicide se trouvant dans la majorité des vins français : l’iprodione. Pour extraire l’iprodione à partir du vin, un challenge important se présentait : le milieu hydroalcoolique est un solvant dipolaire alors que l’interaction du MIP avec l’iprodione se base sur des interactions dipôle-dipôle. Les premières études d’extraction de l’iprodione ont été faites sur un MIP obtenu par polymérisation en masse à partir du méthacrylamide et de l'éthylène glycol diméthacrylate (EGDMA). Le MIP était plus efficace que le NIP (polymère non imprimé) dans des solutions hydroalcooliques ce qui vérifie que l’impression moléculaire était réussie. Un plan d’expériences 23 a été appliqué pour étudier l’influence de 3 facteurs de synthèse de MIP (la méthode de polymérisation, la nature de l'agent réticulant et le type de monomère fonctionnel) sur les propriétés de reconnaissance des polymères vis-à-vis de l’iprodione. 8 MIP et 8 NIP ont été ainsi synthétisés. Les isothermes d'adsorption de l'eau et de l’iprodione par les MIPs et les NIPs ont été déterminées. Des différences significatives entre les polymères ont été mises en évidences impliquant une relation entre l’adsorption de l’eau et l’adsorption de l’iprodione. La formation des empreintes moléculaires au sein des MIP a été démontrée par plusieurs techniques comme la calorimétrie différentielle à balayage et la résonance magnétique nucléaire. Les meilleures propriétés de reconnaissance de l’iprodione sont obtenues avec le MIP synthétisé par précipitation à partir du méthacrylamide comme monomère fonctionnel et de l’EGDMA comme réticulant. Ce MIP a été utilisé en extraction en phase solide (SPE) pour la pré-concentration de l’iprodione dans un vin blanc avec un facteur de pré-concentration égal à 6 et sa sélectivité par rapport à deux fongicides : le pyriméthanil et le procymidone a été démontrée
The aim of this study was the synthesis of a MIP (molecularly imprinted polymer) specific for a fungicide that is found in the majority of the french wine: iprodione. The challenge for extracting iprodione from wine medium was that the hydoralcoholic solution is a dipolar solvent, whereas the interaction between the MIP and iprodione is based on dipolar interactions. The first extraction study of iprodione was made on a MIP synthesized by bulk polymerization using methacrylamide and ethylene glycol dimethacrylate (EGDMA). The MIP was found to be more efficient than the NIP (non-imprinted polymer) in hydroalcoholic solutions which demonstrates that the molecular imprinting was successful. Then we synthesized 8 MIPs and 8 NIPs following an 23 experimental design in order to study the influence of three synthesis factors (the polymerization method, the nature of the crosslinker and the type of the functional monomer) on the iprodione recognition properties of the polymers. The water and the iprodione adsorption isotherms for MIPs and NIPs were determined. The result showed significant differences between the polymers involving a relationship between the water adsorption and the adsorption of iprodione. The molecular imprinting has been demonstrated by several techniques such as the differential scanning calorimetry and the nuclear magnetic resonance. The best recognition properties of iprodione are obtained with the MIP which was synthesized by precipitation polymerization using methacrylamide as functional momonomer and EGDMA as crosslinker. This MIP was used in solid phase extraction (SPE) for pre-concentration of iprodione in a white wine with a pre-concentration factor of 6. Its selectivity versus two fungicides: procymidone and pyrimethanil has been demonstrated

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Le, Moullec Sophie. "Développement de polymères à empreintes moléculaires pour l'extraction sélective de produits de dégradation de neurotoxiques organophosphorés de matrices complexes." Paris 6, 2007. http://www.theses.fr/2007PA066462.

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Ce travail a eu pour objectif de développer des polymères à empreintes moléculaires (MIP) afin d’extraire sélectivement les alkyl alkylphosphonates de matrices complexes. Ces MIP contiennent des cavités conduisant à la reconnaissance d’une molécule dite « empreinte ». Plusieurs MIP ont été synthétisés utilisant le pinacolyl méthylphosphonate comme empreinte puis caractérisés. Ces MIP ont ensuite été utilisé pour le traitement de matrices complexes mettant en évidence leur aptitude à isoler les molécules cibles des interférents. La percolation d’eau sur MIP n’étant pas possible, une méthode de SPE a été développée afin de procéder au changement de solvant. La dernière partie de ce travail a porté sur la compréhension des interactions empreinte-monomères grâce à l’utilisation de la modélisation moléculaire et de la RMN. Les résultats obtenus ont permis de mieux appréhender les mécanismes de formation des cavités et mis en évidence les monomères interagissant fortement avec l’empreinte.

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Xu, Jingjing. "Solid-phase synthesis of molecularly imprinted polymer nanoparticles for protein recognition." Thesis, Compiègne, 2017. http://www.theses.fr/2017COMP2349/document.

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Cette thèse décrit la synthèse de nanoparticules de polymères à empreintes moléculaires (MIP, de l’anglais molecularly imprinted polymer) pour la reconnaissance de protéines, par une approche de synthèse en phase solide. Les polymères à empreintes moléculaires sont des récepteurs biomimétiques synthétisés sur mesure par un processus de nanomoulage du polymère autour de la molécule unique. Ils possèdent ainsi des cavités de reconnaissance spécifiques pour leur molécule cible. La technique de l'impression moléculaire pour les petites molécules cibles est bien établie, alors que l'impression de protéines reste encore un défi en raison de la flexibilité et complexité de leur structure native et de leurs nombreux sites fonctionnels, mais aussi en raison de leur faible stabilité dans des conditions inhabituelles. Par conséquent, une approche de synthèse en phase solide a été développée ici où la protéine est immobilisée sur un support avant la synthèse de nanoparticules hydrosolubles de MIP par polymérisation radicalaire. Les MIPs obtenus ont des affinités comparables à celles des anticorps, et des réactivités croisées faibles. Ils possèdent des avantages tels qu'une stabilité meilleure, un coût plus faible et peuvent potentiellement être régénérés et réutilisés, devenant ainsi des alternatives prometteuses aux anticorps naturels. Nous avons fabriqué des MIPs contre des protéases à sérine, telles la trypsine et la kallikréine, mais aussi contre un épitope peptidique de la protéine gp41 du VIH. Des nanogels de MIP thermosensibles ont été synthétisés dans un réacteur sous la forme d’une colonne thermostatée ou une boîte de Pétri, par polymérisation radicalaire initiée par voie thermique ou photochimique. Un simple changement de la température permet de libérer les MIPs de la protéine immobilisée. Ces MIPs sont hydrosolubles en fonction de la température et ont un diamètre inférieur à 100 nm. Leur affinité pour leur cible est élevée, avec un Kd du nano ou picomolaire. Ces 'anticorps synthétiques' ont été appliqués dans des tests d'adsorption sur microbalance à cristal de quartz, mais également comme 'chaperons synthétiques'. Des études préliminaires de la protection des protéines d'une dénaturation thermique ou par un pH défavorable ont été effectuées. L'utilisation d'un iniferter pour initier la photopolymérisation vivante du MIP a permis de synthétiser des nanogels de type core-shell. En introduisant des marqueurs fluorescents dans les MIPs, les tests d’immunoessai dans des fluides biologiques ont été démontrés, ce qui indique le grand potentiel de ces MIPs dans le diagnostic clinique. En conclusion, nous avons développé une nouvelle approche de synthèse de nanoparticules de MIP hydrosoluble ayant une haute affinité pour une protéine, utilisables à la place des anticorps dans des applications dans le monde réel tel que la détection de protéines biomarqueurs dans des échantillons complexes, et potentiellement comme principe actif in vivo
This thesis describes the synthesis, by a solid-phase synthesis approach, of nanoparticles of molecularly imprinted polymers (MIPs) for the recognition of proteins. Molecularly imprinted polymers are biomimetic receptors synthesized by a nanomolding process of the polymer around single molecules. They therefore possess specific recognition cavities for their target molecule. The technique of molecular imprinting for small target molecules is well established, while protein imprinting remains a challenge due to the flexibility and complexity of their native structure and functional sites, but also because of their low stability under unusual conditions. Therefore, a solid-phase synthesis approach has been developed where the protein is immobilized on a support before the synthesis of water-soluble MIP nanogel particles by radical polymerization. The MIPs obtained have affinities comparable to those of antibodies, and low cross-reactivities. They have advantages such as better stability, lower cost, and can potentially be regenerated and reused, thus becoming promising alternatives to real antibodies. We have synthesized MIPs against serine proteases such as trypsin, and kallikrein, but also against a peptide epitope of the HIV gp41 protein. Thermosensitive MIP nanogels were synthesized in a thermostated column-type reactor or a petri dish, by thermally or photo-initiated radical polymerization. Their thermosensitivity allows the MIPs to be released from the immobilized protein by a simple temperature change. They are water-soluble as a function of temperature and have a diameter of less than 100 nm. Their affinity for their target is strong, with a Kd in the nano or picomolar range. These 'synthetic antibodies' have been applied in binding assays with quartz crystal microbalance, but also as 'synthetic chaperones'. Preliminary studies of the protection of proteins from thermal denaturation or from denaturation by an unfavorable pH have been carried out. The use of an iniferter to initiate the living photopolymerization of MIP made it possible to synthesize nanogels of core-shell type. By introducing fluorescent markers into MIPs, immunoassay applications in biological fluids have been demonstrated, indicating the great potential of these MIPs in clinical diagnostics. In conclusion, we have developed a novel approach to the synthesis of soluble MIP nanoparticles having high affinity for a protein, usable in place of antibodies in real world applications such as the detection of biomarker proteins in complex samples, and potentially as an active principle in vivo

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Santos, Wilney de Jesus Rodrigues. "Nanoreatores biomimeticos a peroxidase baseados em MIP : uma estrategia promissora para determinação de compostos fenolicos." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/248404.

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Orientador: Lauro Tatsuo Kubota
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Quimica
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Resumo: O presente trabalho descreve as aplicações de nanoreatores biomiméticos à peroxidase baseados em MIP ("Molecularly Imprinted Polymers") como uma ferramenta promissora para determinação de substâncias de grande interesse biológico e ambiental, tais como os compostos fenólicos (4-aminofenol e serotonina). Neste sentido, a síntese dos MIPs foi baseada na polimerização convencional em "bulk". Cada polímero foi sintetizado a partir do ácido metacrílico (monômero funcional), etileno glicoldimetilacrilato (reagente de ligação cruzada), 2¿2-azo-bis-isobutironitrila (iniciador radicalar), em presença de Fe(III)protoporfrina(IX) (hemina) como centro catalítico, o qual é responsável pela mimetização do sítio ativo da peroxidase, criando portanto, um polímero com impressão molecular cataliticamente ativo para o reconhecimento do 4-aminofenol e serotonina (moléculas molde). Além disso, a fim de avaliar a seletividade do material, foram preparados, paralelamente, polímeros sem a impressão molecular (NIP Non Imprinted Polymers) e também na ausência de hemina. Os MIPs foram caracterizados pelas técnicas de espectroscopia no infravermelho, área superficial específica, volume específico dos poros, análise termogravimétrica, microscopia eletrônica de varredura. Parâmetros cinéticos, incluindo valores de velocidade máxima, Vmax e constante aparente de Michaelis¿Menten, Km foram obtidas pelo gráfico de Lineweaver-Burk. Para aplicação analítica, em amostras de água e soro sanguíneo, sistemas amperométricos foram otimizados através de análise multivariada
Abstract: The present work describes the applications of biomimetic nanoreactor to the based peroxidase in molecularly imprinted polymers (MIP) as a promising tool for determination of substances of high biological and environmental interest, such as phenolic compounds (4-aminophenol and serotonin). In this sense, the synthesis of MIPs was based on the conventional polymerization in bulk. Each polymer was synthesized from methacrylic acid (functional monomer), ethylene glycol dimethacrylate (cross-linking reagent), 2,2'-azobis-isobutyronitrile (initiator), in the presence of Fe(III)protoporphyrin(IX) (hemin) as a catalytic center, which is responsible for the mimic of the active site of peroxidase, creating therefore, a molecularly imprinted polymer active catalytically for the recognition of the 4-aminophenol and serotonin (template molecules). Furthermore, in order to evaluate the selectivity of the material, were prepared, parallel, polymers without the molecular impression (NIP - Non imprinted polymers) and also in the hemin absence. The MIPs were characterized by the techniques of infrared spectroscopy, specific surface area, specific pore volume, thermogravimetric analysis, scanning electron microscopy. Kinetic parameters, including values for maximum rate, Vmax and Michaelis-Menten apparent constant, Km were obtained from Lineweaver-Burk plots. For analytical application, in samples of water and blood serum, amperometric systems were optimized through multivariate analysis
Doutorado
Quimica Analitica
Doutor em Ciências

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COSTA, Alessandra Carolina da. "Síntese e estudo de um polímero de impressão molecular (Molecularly Imprinted Polymer, MIP) usando bisfenol A como molécula molde para aplicação em extração em fase sólida (Molecularly Imprinted Solid Phase Extraction, MISPE)." reponame:Repositório Institucional da UNIFEI, 2017. http://repositorio.unifei.edu.br/xmlui/handle/123456789/1031.

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Para otimizar o processo de síntese do polímero de impressão molecular (MIP) foi realizado um planejamento de triagem estatística Box-Behnken codificados em três níveis, sendo, baixo, médio e alto (-1, 0 e +1) e três fatores, sendo, tipo de solvente, tempo de reação e velocidade de agitação. A técnica cromatográfica utilizada foi a Cromatografia Líquida de Alta Eficiência (CLAE), com detector por Fluorescência (FLD), validada e otimizada de acordo com as figuras de mérito (seletividade, sensibilidade, linearidade, precisão, exatidão, robustez, limite de detecção e limite de quantificação). Para a síntese do MIP, em uma ampola de síntese adicionou-se o BFA como molécula-molde (do inglês Template), ácido metacrílico (MAA) como monômero funcional, o solvente acetonitrila, clorofórmio ou tolueno, etilenoglicol dimetacrilato (EGDMA) como agente de ligação cruzada e o 4,4’-azo-(ácido-4-cianovalérico) (AACV) como iniciador radicalar. Também foi realizado a síntese de um polímero não impresso (NIP) ausente de molécula molde BFA. Após testes prévios da adsorção e de seletividade dos MIPs empacotados em cartucho de extração em fase sólida foram selecionados os melhores materiais poliméricos para estudos posteriores. O MIP sintetizado apresentou aparência de polímero amorfo, aspectos esbranquiçados e uma estrutura aparentemente rígida. A recuperação do MIP ficou compreendida na faixa de 77,20 – 87,54% com um coeficiente de variação (CV) inferior a 10%. A recuperação do polímero não impresso foi inferior à do MIP. A quantidade remanescente de molécula-molde presente no MIP foi inferior a 1% indicando que a técnica por extração Soxhlet utilizada para a remoção da molécula-molde foi eficiente. A seletividade do MIP e NIP otimizado foi comparada com o composto fenol que se mostrou seletivo para o MIP e NIP com uma recuperação de 48,20% (MIP) e 48,25% (NIP) com CV inferior a 45%. Os materiais poliméricos sintetizados foram caracterizados por espectroscopia de absorção molecular na região do infravermelho por transformada de Fourier (FTIR), microscopia eletrônica por varredura (MEV), analisador de tamanho de partículas, analisador de área superficial e porosidade por adsorção/dessorção com nitrogênio pelo método B.E.T, análise termogravimétrica (TGA) e calorimetria exploratória diferencial (DSC).

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Gonzato, Carlo. "Chemical nanosensors based on molecularly imprinted polymer nanocomposites synthesized by controlled radical polymerization." Compiègne, 2012. http://www.theses.fr/2012COMP2035.

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Les polymères à empreintes moléculaires (MIP, pour molecularly imprinted polymers en anglais) sont des récepteurs synthétiques, parfois appelés "anticorps en plastique", capables de reconnaitre et fixer spécifiquement une molécule cible. L’impression moléculaire s’est imposée, durant les trente dernières années, comme une technique pour la synthèse des structures réticulées possédant une remarquable affinité et sélectivité vis-à-vis d’une espèce chimique utilisée comme molécule empreinte dans un procédé de moulage au niveau moléculaire. La grande variété de matériaux et de formats accessibles à cette technique lui ont permis de trouver un grand nombre d’applications, telles que la séparation, les capteurs, la catalyse, le ré-largage contrôlé de médicaments. Depuis leur apparition, la plupart des MIPs a été synthétisée par polymérisation radicalaire libre (FRP) des monomères vinyliques. Cette méthode de polymérisation représente un excellent choix en termes de simplicité de mise en place, tolérance par rapport aux solvants et aux différents groupements fonctionnels des ingrédients. Cependant, plusieurs désavantages liés à cette technique limitent la possibilité d’obtenir un contrôle adéquate vis-à-vis de certaines caractéristiques fondamentales pour des applications en nano-technologies. L’introduction des techniques de polymérisation radicalaire contrôlée/vivante (CRP) a donc représentée une avancée importante et a permis de dépasser certains limites associés aux MIPs synthétisés par FRP. Dans ce contexte, ce travail de thèse a étudié les avantages provenant de l’utilisation d'une méthode CRP, le RAFT, pour la synthèse des MIP. Ce travail a été mené en se focalisant sur les caractéristiques principales des CRPs : le caractère vivant et, en même temps, contrôlé. Dans un premier temps, nous avons utilisé l’aspect vivant de la polymérisation pour la synthèse des nanocomposites MIP, possédant des propriétés superparamagnétiques. Celle-ci a été effectuée par polymérisation de couches p(EGDMA-co-MAA) par RAFT amorcée à la surface des particules de Fe3O4 préfonctionnalisées avec des groupements amine. Le greffage de ces couches a été obtenu en employant des ultrasons comme source d'agitation, et en testant différents solvants pour en apprécier l’influence sur la structure et la morphologie des composites résultants. Nous avons démontré que le greffage se produit d’une façon homogène, et que grâce au caractère vivant de la polymérisation RAFT, les composites peuvent être fonctionnalisés davantage, par exemple par des chaines p(EGMP), pour ajuster leur propriétés de surface. Dans un deuxième temps, nous nous sommes consacrés à une étude comparative visant la mise en évidence des avantages de la RAFT par rapport à la FRP en termes de performances des MIP acryliques et méthacryliques. Pour mieux apprécier les différences induites par la méthode de polymérisation, le dégrée de réticulation et donc la flexibilité des réseaux ont été variés de façon systématique. Cette stratégie a permis de bien apprécier les différences induites par chaque technique de polymérisation. Les résultats ont démontré que la RAFT permet de synthétiser des MIPs ayant une meilleure affinité pour leur molécule cible, et que cette amélioration est due à une distribution plus homogène des points de réticulation au sein du réseau. Finalement, nous avons appliqué la RAFT pour la synthèse de nanocapteurs individuels basés sur des composite MIP intégrant des nanoparticules d'or, et utilisant la spectroscopie Raman exaltée (SERS) pour la détection
Molecularly imprinted polymers (MIPs) are synthetic receptors, also known as antibody mimics, that can specifically bind target molecules. Molecular imprinting has emerged, over the last 30 years; it is an extremely versatile strategy for synthesizing networks possessing high affinity and selectivity for a chemical species, used as a molecular template during their synthesis. The wide variety of materials and formats that are accessible through this strategy has resulted in a broad spectrum of applications for such MIPs, ranging from separation to sensing, catalysis, drug delivery, etc. Since the beginning, the great majority of the imprinted networks has been synthesized by assembling vinyl monomers via free-radical polymerization (FRP). This polymerization method represents a convenient choice for synthesizing MIPs, due to its easy setup, versatility, tolerance with respect to many solvents and functional groups. However, some drawbacks greatly affect the possibility of achieving of suitable degree of control over some “polymeric” parameters which become important for specific applications. The introduction of controlled/”living” radical polymerization (CRP) techniques has then represented an opportunity for MIPs to reduce, and in some cases even to overcome, some of their limits arising from FRP. In this respect, this Ph. D. Thesis has studied how the use of RAFT polymerization, one of the most applied CRPs, can be advantageously used to syntheze MIPs. This has been done by focusing on the main characteristics of CRPs: their living and controlled nature. The living nature has been exploited during the first part of this work, which involved the synthesis of superparamagnetic molecularly imprinted nanocomposites via surface-initiated RAFT polymerization of p(EGDMA-co-MAA) on amino-modified Fe3O4 nanoparticles. The polymer grafting has been performed using an unusual stirring technique (i. E. Ultrasonication) during the polymerization step, and by testing different polymerization solvents for evaluating their effect on the composite structure. It has been observed that the grafting resulted in homogeneous polymer layers, the thickness of which could be controlled by adjusting the RAFT/radical source ratio. Moreover, the living nature of RAFT fragments has been exploited for post-functionalizing the surface of a composite particle with p(EGMP) brushes, thus demonstrating the potential of fine-tuning the particle surface properties through the living chain ends. In the second part of the thesis, an in-depth study has been performed on the effects induced by the use of controlled (RAFT) polymerization conditions on the binding behaviour and structural parameters of bulk acrylic and methacrylic MIPs and the corresponding non-imprinted polymers, synthesized by RAFT and FRP with varying cross-linking degree. This strategy actually provided scaffolds with progressively increased degree of flexibility (especially in the case of acrylics) which allowed visualize the enhancement of binding and structural differences arising from the polymerization technique. As a result, it has been observed that the use of controlled (RAFT) conditions induced, on the imprinted networks, an increased template affinity over equivalent FRPs, and it has been demonstrated that this improved affinity can be related to more homogeneous distributions of the cross-linking points achieved during RAFT polymerization. The third part presents preliminary results toward the synthesis by RAFT of individual multi-composite MIP nanosensors using enhanced Raman spectroscopy (SERS) for detection

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Wagner, Sabine [Verfasser], Ulrich [Gutachter] Panne, Kannan [Gutachter] Balasubramanian, and Annabelle [Gutachter] Bertin. "Sensory molecularly imprinted polymer (MIP) coatings for nanoparticle- and fiber optic-based assays / Sabine Wagner ; Gutachter: Ulrich Panne, Kannan Balasubramanian, Annabelle Bertin." Berlin : Humboldt-Universität zu Berlin, 2019. http://d-nb.info/1188714554/34.

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Krstulja, Aleksandra. "Development of molecularly imprinted polymers for the recognition of urinary nucleoside cancer biomarkers." Thesis, Orléans, 2015. http://www.theses.fr/2015ORLE2009.

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Ce rapport de thèse présente l’étude de la technologie des empreintes moléculaires pour le développement de polymères spécifiques et sélectifs envers des biomarqueurs urinaires nucléosidiques du cancer colorectal chez l’Homme. L’objectif principal était de développer des polymères à empreintes moléculaires compatibles aux milieux aqueux en utilisant la technique du « dummy template », l’approche non-covalente and la polymérisation radicalaire en masse. Nous nous sommes concentrés principalement sur la qualité des polymères à partir de leur formulation, c’est-à-dire la spécificité et la sélectivité. Cela a été mené de façon empirique d’abord par la production de poudres issues de polymères monolithiques. Ainsi, pour atteindre les objectifs fixés, nous avons exploré le choix de la molécule « template ». Une étude de modèle est présentée au chapitre 3, en utilisant trois nucléosides 2’,3’,5’-peracétylés comme molécule empreinte dans une approche « dummy template ». Ensuite, en s’appuyant sur la connaissance apportée par le chapitre 3, nous avons développé des polymères à empreintes moléculaires (MIPs) sélectifs de la pseudouridine et de la N7-méthylguanosine dans les chapitres 4 et 5, respectivement, en utilisant la 2’,3’,5’-tri-O-acétylpseudouridine et la 2’,3’,5’-tri-O-acétylguanosine comme templates. L’étude de la rétention des nucléosides recherchés et de leurs analogues structuraux menée par chromatographie en phase liquide et par analyse frontale a permis de déterminer la capacité des différents polymères et de connaître leur comportement dans de l’urine synthétique. Finalement, pour évaluer la possible application de ces polymères dans un échantillon réel, l’urine humaine, la technique de l’extraction sur phase solide à empreintes moléculaires ou MISPE a été développée. Ainsi, une purification sélective des biomarqueurs cibles, tels que la pseudouridine et la N7-méthylguanosine, dans des échantillons d’urines a pu être démontrée
This thesis report presents the exploration of molecularly imprinted polymer (MIP) technology for developing of a sensitive and selective polymers used in urinary nucleoside biomarker recognition. The main goal was to develop water compatible MIPs prepared by a “dummy template” imprinting technology, using a non-covalent approach and radical-polymerization in bulk. We were focusing mostly on the polymer quality in the formulation (rigidity, stability and repeatability). This was chosen empirically first by production of powders from monolithic MIP. Thus, to accomplish the stated goals, we have explored the choice of the template molecule. A model study presented by Chapter 3, using three 2’3’5’-tri-Operacylateduridine nucleosides as templates in a “dummy” template approach was first developed. Then, applying the knowledge of the type of template choice, we developed a selective MIP for recognition of pseudouridine and N7-methylguanosine in the studies presented in Chapter 4 and Chapter 5 respectively. By using 2’3’5’-tri-O-acetylpseudouridine and 2’3’5’-tri-O-acetylguanosine as templates. Chromatographic methods like HPLC retention and frontal analysis were used in the interest of determining the binding capacity of synthesized polymers, and the behavior in synthetic urine. Finally, to evaluate the possible application of these polymers in urine, molecularly imprinted solid phase extraction (MISPE) was developed. Selective purification of urine samples containing pseudouridine and N7-methylguanosine obtained in the end

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Liporini, Amanda Quatrocchio. "Avaliação de diferentes técnicas de preparo de amostras e perspectiva de síntese de um polímero seletivo para a concentração de N-nitrosodietanolamina (NDELA) em matrizes cosméticas." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/75/75135/tde-29062016-104007/.

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A ocorrência de N-nitrosaminas em produtos cosméticos e de higiene pessoal está relacionada com os ingredientes utilizados na formulação de tais artefatos. A N-nitrosodietanolamina (NDELA) é formada na presença da dietanolamina associada a outros componentes, tais como íons nitrito empregados como conservantes em matrizes cosméticas. São cancerígenas e, portanto, as condições em que tais itens de consumo são fabricados é um fator que deve ser mensurado. Assim, é aconselhável a realização de estudos que mostrem a ocorrência de NDELA em cosméticos, seus principais métodos de determinação, bem como os aspectos legais que indicam os níveis de concentração deste contaminante presente em diversas formulações. Foi avaliado neste trabalho o potencial de algumas técnicas de preparo de amostras na concentração de NDELA, tais como microextração líquido-líquido dispersiva em fase reversa (DLLME-RP), extração líquido-líquido com salting out e clean up no modo on-line. Os resultados obtidos foram confrontados com os dados presentes na literatura. Adicionalmente, utilizando os conceitos de polimerização via sol-gel e via precipitação para a síntese de polímeros molecularmente impressos (MIP), propõem-se uma possível rota sintética para a confecção de materiais seletivos para a pré-concentração da nitrosamina.
The occurrence of N-nitrosamines in cosmetic and personal hygiene are related to the ingredients used in the formulation of such artefacts. N-nitrosodiethanolamine (NDELA) is formed in the presence of diethanolamine associated with other components such as nitrite ions employed as preservatives in cosmetic matrices. They are carcinogenic and, therefore, the conditions under which such consumer items are produced is a factor that must be measured. It is therefore advisable to carry out studies that show the occurrence of NDELA in cosmetics, their main methods of determination as well as the legal aspects that indicate the levels of concentration of this contaminant present in various formulations. It was evaluated in this study the potential for some sample preparation techniques in the concentration of NDELA such as liquid-liquid microextraction dispersive reverse phase (DLLME-RP) liquid-liquid extraction with salting out and clean up online. The results were compared with data in the literature. Additionally, using the concepts of polymerization via sol-gel and precipitation route for the synthesis of molecularly imprinted polymers (MIP) are proposed as a possible synthetic route for the preparation of materials for selective pre-concentration of nitrosamine.

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Nestora, Sofia. "Molecularly imprinted polymers as selective sorbents for recognition in complex aqueous samples." Thesis, Compiègne, 2017. http://www.theses.fr/2017COMP2346/document.

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Dans cette thèse, nous avons démontré la faisabilité de la préparation de polymères à empreinte moléculaires (MIP) hautement sélectifs pour la reconnaissance dans des matrices aqueuses complexes avec des applications dans les cosmétiques et en technologie alimentaire. Les MIP (de l'anglais molecularly imprinted polymers) sont des récepteurs synthétiques comparables aux anticorps, qui sont synthétisés par co-polymérisation de monomères fonctionnels et réticulants en présence d'un gabarit moléculaire. Leurs propriétés de reconnaissance moléculaire, associées à leur grande stabilité, robustesse mécanique, faible coût et leur synthèse facile les rendent extrêmement intéressants comme matériaux de capture sélective, avec des applications dans les séparations analytiques, la détection et la vectorisation des médicaments. Cependant, leur reconnaissance sélective dans des milieux aqueux reste toujours problématique et c'est l'une des raisons de leur expansion commerciale restreinte. Dans une première partie, nous avons développé un MIP fonctionnant en milieu aqueux pour son application comme ingrédient actif dans un déodorant. Les odeurs corporelles sont principalement dues à des acides gras volatils générés à partir de leurs précurseurs, des conjugués de glutamine par des enzymes hydrolytiques produites à partir de bactéries présentes sur la peau. La plupart des anti-transpirants et des déodorants actuellement commercialisés contiennent des sels d'aluminium et des agents antibactériens non spécifiques, respectivement. Cependant, l'utilisation extrêmement étendue de ces produits nécessite des solutions alternatives en ce qui concerne divers problèmes (environnement, respect de l'écosystème de la peau, toxicité, etc.). Pour cette raison, un MIP a été synthétisé pour capturer les précurseurs conjugués de glutamine afin qu'ils ne soient plus disponibles aux bactéries, empêchant ainsi leur transformation en composés malodorants. Afin de générer des liaisons sélectifs dans des environnements aqueux, un monomère à base d'amidinium qui peut former une interaction électrostatique stoechiométrique forte avec les groupes carboxyle sur le gabarit moléculaire a été synthétisé. Le MIP, mélangé dans une formulation dermo-cosmétique, pourrait capter sélectivement les précurseurs conjugués de glutamine, au milieu d'une multitude d'autres molécules présentes dans la sueur humaine. En outre, le MIP n’affecte pas les bactéries de la peau, ouvrant la voie à des déodorants innovateurs de nouvelle génération, moins problématiques pour la santé. Dans une deuxième partie, nous avons développé une procédure rapide et efficace basée sur l'extraction en phase solide à empreinte moléculaire (MISPE) pour la purification sélective de la bétanine et de son stéréoisomère l’isobétanine à partir d'extraits de betterave. La bétanine est un pigment naturel ayant un fort pouvoir antioxydant et dont les propriétés pharmacologiques sont de plus en plus étudiées. Ce pigment est actuellement utilisé comme simple colorant alimentaire. Dans notre étude, l'acide dipicolinique a été utilisé comme gabarit moléculaire pour la synthèse de MIP, en raison de sa similarité structurelle avec le groupe chromophore de la bétanine. Les procédures MISPE ont été optimisées permettant l'élimination presque complète des glucides issus de la matrice végétale ainsi que la majorité des protéines, ce qui permet d'obtenir un rendement élevé d'extraction de la bétanine / isobétanine en une seule étape. De plus, toute la procédure d'extraction a été réalisée dans des solvants respectueux de l'environnement, tels que l'éthanol ou l'eau. Pour conclure, nous sommes convaincus que ce travail pave le chemin au développement d'une nouvelle génération des MIP fonctionnant en milieu aqueux avec des propriétés de reconnaissance améliorées dans des environnements complexes, qui pourra s'appliquer également à d'autres domaines biotechnologiques et biomédicaux
In this thesis, we have demonstrated the feasibility of preparing highly selective molecularly imprinted polymers (MIPs) for recognition in complex aqueous matrices with applications in cosmetics and food technology. MIPs are synthetic tailor-made receptors, with binding affinities and specificities comparable to those of natural antibodies. Their molecular recognition properties, combined with their high stability, mechanical robustness, low cost and easy synthesis make them extremely attractive as selective capture materials with applications in analytical and preparative separations, sensing and drug delivery, among others. However, their selective recognition in aqueous samples still remains problematic and is one of the reasons for their so far lilited commercial expansion. In the first part, we developed a water compatible MIP for its application as an active ingredient in a deodorant. Body odors are mainly due to volatile fatty acids generated from their glutamine conjugate precursors by hydrolytic enzymes from bacteria present on the skin. Most currently marketed anti-perspirants and deodorants contain, respectively aluminum salts and unspecific antibacterials. However, the extremely wide use of these products requires alternative solutions with regard to various problems (environmental, respect of skin ecosystem, toxicity, etc.). For this reason, a MIP was developed to capture the glutamine conjugate precursors so that they are no longer available to the bacteria, thus preventing their transformation to malodorous compounds. In order to generate binding selectivity in aqueous environments, an amidinium-based monomer which can form a strong stoichiometric electrostatic interaction with the carboxyl groups on the template, was synthesized. The MIP, blended in a dermo-cosmetic formulation, could capture selectively the glutamine precursors, amidst a multitude of other molecules present in human sweat. Furthermore, the MIP did not affect the skin bacteria, paving the way to an innovative and 'safer ' future-generation deodorant. In the second part, we developed a fast and efficient procedure based on molecularly imprinted solid phase extraction (MISPE) for the selective clean-up of betanin and its stereoisomer isobetanin from red beetroot extracts. Betanin is a natural pigment with significant antioxidant and biological activities currently used as food colorant. Dipicolinic acid was used as template for the MIP synthesis, because of its structural similarity to the chromophore group of betanin The MISPE procedures were optimized allowing the almost complete removal of carbohydrates and the majority of proteins, resulting in high extraction recovery of betanin / isobetanin in a single step. Moreover, the whole extraction procedure was performed in environmentally friendly solvents with either ethanol or water. To conclude, we believe that this study paves the way towards the development of a new generation of water compatible MIPs with improved recognition properties in highly complex aqueous environments, and should be applicable to other biotechnological and biomedical areas as well

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Kaya, Zeynep. "Controlled and localized synthesis of molecularly imprinted polymers for chemical sensors." Thesis, Compiègne, 2015. http://www.theses.fr/2015COMP2220.

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Les polymères à empreintes moléculaires (MIP), également appelés "anticorps en plastique", sont des récepteurs biomimétiques synthétiques qui sont capables de reconnaître et lier une molécule cible avec une affinité et une spécificité comparables à celles des récepteurs naturels tels que des enzymes ou des anticorps. En effet, les MIP sont utilisés comme éléments de reconnaissance synthétiques dans les biocapteurs et biopuces pour la détection de petits analytes et les protéines. La technique d'impression moléculaire est basée sur la formation de cavités de reconnaissance spécifiques dans des matrices polymères par un procédé de moulage à l'échelle moléculaire. Pour la conception de capteurs et biopuces, une cinétique d'adsorption et une réponse du capteur rapide, l'intégration des polymères avec des transducteurs, et une haute sensibilité de détection sont parmi les principaux défis. Dans cette thèse, ces problèmes ont été abordés par le développement de nanocomposites MIP / d'or via le greffage du MIP sur les surfaces en utilisant des techniques de polymérisation dédiées comme l'ATRP qui est une technique de polymérisation radicalaire contrôlée (CRP). Ces techniques CRP sophistiquées sont en mesure d'améliorer considérablement les matériaux polymères. L'utilisation de l'ATRP dans le domaine de MIP a été limitée jusqu'à présent en raison de son incompatibilité inhérente avec des monomères acides comme l'acide méthacrylique (MAA), qui est de loin le monomère fonctionnel le plus largement utilisé dans les MIP. Ici, un nouveau procédé est décrit pour la synthèse de MIP par ATRP photo-initiée utilisant fac-[Ir(Ppy)3] comme catalyseur. La synthèse est possible à température ambiante et est compatible avec des monomères acides. Cette étude élargit considérablement la gamme de monomères fonctionnels et de molécules empreintes qui peuvent être utilisés lors de la synthèse de MIP par ATRP. La méthode proposée a été utilisée pour la fabrication de nanocomposites hiérarchiquement organisés sur des surfaces métalliques nanostructurés avec des nano-trous et nano-ilots, présentant des effets plasmoniques pour l'amplification du signal. La synthèse de films de MIP à l'échelle du nanomètre localisés sur la surface d'or a été démontrée. Des méthodes de transduction optiques, à savoir la résonance de plasmons de surface localisée (LSPR) et la spectroscopie Raman exaltée par effet de surface (SERS) ont été exploitées. Ces techniques se sont montrées prometteuses pour l'amélioration de la limite de détection dans la détection d'analytes biologiquement pertinents, y compris les protéines et le médicament propranolol
Molecularly imprinted polymers (MIPs), also referred to as plastic antibodies, are synthetic biomimetic receptors that are able to bind target molecules with similar affinity and specificity as natural receptors such as enzymes or antibodies. Indeed, MIPs are used as synthetic recognition elements in biosensors and biochips for the detection of small analytes and proteins. The molecular imprinting technique is based on the formation of specific recognition cavities in polymer matrices by a templating process at the molecular level. For sensor and biochip development, fast binding kinetics of the MIP for a rapid sensor response, the integration of the polymers with transducers, and a high sensitivity of detection are among the main challenges. In this thesis, the above issues are addressed by developing MIP/gold nanocomposites by grafting MIPs on surfaces, using dedicated techniques like atom transfer radical polymerization (ATRP) which is a versatile controlled radical polymerization (CRP) technique. Theses ophisticated CRP techniques, are able to greatly improve the polymeric materials. The use of ATRP in the MIP field has been limited so far due to its inherent incompatibility with acidic monomers like methacrylic acid (MAA), which is by far the most widely used functional monomer. Herein, a new method is described for the MIP synthesis through photo-initiated ATRP using fac-[Ir(ppy)3] as ATRP catalyst. The synthesis is possible at room temperature and is compatible with acidic monomers. This study considerably widens the range of functional monomers and thus molecular templates that can be used when MIPs are synthesized by ATRP. The proposed method was used for fabrication of hierarchically organised nanocomposites based on MIPs and nanostructured metal surfaces containing nanoholes or nanoislands, exhibiting plasmonic effects for signal amplification. The fabrication of nanometer scale MIP coatings localized on gold surface was demonstrated. Optical transduction methods, namely Localized Surface Plasmon Resonance (LSPR) and Surface Enhanced Raman Spectroscopy (SERS) were exploited and shown that they hold great promise for enhancing the limit of detection in sensing of biologically relevant analytes including proteins and the drug propranolol

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Manzoor, Suryyia 1984. "Materiais impressos molecularmente (MIMs) : síntese, caracterização e avaliação." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/250225.

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Orientadores: Adriana Vitorino Rossi, Regina Buffon
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química
Made available in DSpace on 2018-08-22T19:48:13Z (GMT). No. of bitstreams: 1 Manzoor_Suryyia_D.pdf: 4523839 bytes, checksum: 9aa2a7bc8376699193b0d5e83f0ec0f5 (MD5) Previous issue date: 2013
Resumo: Este trabalho envolveu um estudo elaborado da técnica de impressão molecular para síntese, caracterização e avaliação de materiais impressos molecularmente (MIMs) para fluconazol (FLU), cafeína (CAF) e antocianinas (ACYs). O polímero de impressão molecular para FLU (FLUMIP) foi sintetizado utilizando-se ácido metacrílico (monômero funcional), etilenoglicoldimetacrilato (EGDMA) (agente reticulador) e acetonitrila em polimerização térmica. O FLUMIP foi caracterizado e aplicado como sorvente em cartuchos de extração em fase sólida (SPE). Sua capacidade de interação seletiva com o analito foi avaliada, obtendo-se alta afinidade para FLU, em comparação com análogos estruturais, com limite de detecção menor que 1,63X10 mmol/L com cromatografia de ultra alta eficiência acoplada com espectrometria de massas. Este MIP foi usado em cartuchos de SPE para extrair o analito de medicamento em cápsula, com recuperação de 91±10 % (n=9). Outro MIM obtido foi uma sílica organicamente modificada (ORMOSIL) para extração de CAF, a partir da reação de metacrilato de 3- (trimetoxisilil) propila e acetato de vinila, seguindo-se condensação e hidrólise com tetraetilortosilicato usando CAF como molécula modelo. Este ORMOLSIL foi caracterizado e testado quanto à sua eficácia de extrair CAF de amostras de café, com recuperação de 88±5 % (n=9); ele atuou como grupo seletivo com alta porcentagem de recuperação para teofilina (77 %) e teobromina (82 %). Limites de detecção e quantificação 5,14x10 e 1,71x10 mmol/L respectivamente foram obtidos com cromatografia líquida de alta eficiência. Também foi sintetizado um MIP usando rutina molécula modelo (RUTMIP), acrilamida (monômero funcional), EGDMA (agente reticulador) e tetraidrofurano por polimerização em bulk. Embora tenha sido alcançada impressão bem sucedida de rutina, confirmada pela comparação de afinidade de RUTMIP em aplicação de SPE (12 vezes maior que afinidade do polímero não impresso), não se alcançou a seletividade esperada para ACYs utilizando o RUTMIP
Abstract: This work involves an elaborative study of molecularly imprinting technique. Keeping in view its robustness and selectivity, this technique was applied for the synthesis of molecularly imprinted materials for the extraction of fluconazole (FLU), caffeine (CAF) and anthocyanins (ACYs). Molecularly imprinted polymer (MIP) for FLU (FLUMIP) was synthesized using methacrylic acid (functional monomer), ethyleneglycoldimethacrylate (crosslinker) and acetonitrile through thermal polymerization. The FLUMIP was characterized and applied as sorbent in solid phase extraction (SPE) cartridges. It was then evaluated for its ability to selectively interact with the analyte and presented an apparent affinity for FLU, which was confirmed by comparing it with structural analogues. The application of ultra high performance liquid chromatography with spectrometer mass detection, allowed a limit of detection 1.63x10 mmol/L. Furthermore, the SPE procedure was applied to extract FLU from medicine samples with recovery of 91±10 % (n=9). An organically modified silica (ORMOSIL) for CAF was also synthesized by reacting vinyl acetate and 3- (trimethoxysilyl) propyl methacrylate, followed by the condensation and hydrolysis with tetraethyl orthosilicate, using CAF as template molecule. The ORMOSIL was characterized and tested for its efficiency to extract the analyte from coffee samples and the percentage recovery of 88±5 % (n=9) was obtained. The cross reactivity studies for theophylline and theobromine showed high recovery (77 % and 82% respectively). The limit of detection and quantification, 5.14x10 and 1.71x10 mmol/L respectively, were achieved using high performance liquid chromatography. Also, a MIP for ACYs (RUTMIP) was synthesized using rutin (template molecule), EGDMA (cross linker) and tetrahydrofuran by the bulk polymerization method. A successful imprinting of rutin was attained. This can be confirmed by the high affinity of rutin for MIP (12 times greater than non imprinted polymer) during SPE procedure; however, the RUTMIP was not efficient enough to selectively extract ACYs from vegetal extracts
Doutorado
Doutora em Ciências

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Bougrini, Madiha. "Étude de systèmes multicapteurs utilisant des capteurs chimiques, électrochimiques et des biocapteurs pour des applications en agroalimentaire." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSE1062.

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Les capteurs et les biocapteurs sont des moyens d’analyse en plein essor à la fois rapides, sensibles, sélectifs et peu coûteux, applicables à des domaines très variés (agroalimentaire, environnement, biomédical…). Dans ce travail de recherche, nous nous sommes intéressés au développement de trois dispositifs à savoir un nez et une langue électroniques à base de systèmes multicapteurs pour l’analyse des odeurs et des saveurs ainsi que les biocapteurs. Les deux premiers dispositifs ont permis dans un premier temps de caractériser et de détecter les fraudes dans les produits de l’industrie agroalimentaire. Ainsi, nous sommes parvenus à détecter les pratiques frauduleuses dans l’huile d’argan par le nez et par la langue électroniques. Nous avons, par ailleurs, réussi à caractériser des miels de différentes origines géographiques et botaniques et à détecter l’adultération du miel pur par l’utilisation d’une langue électronique voltammétrique. Enfin, nous avons démontré l’efficacité des systèmes de nez et de langue électroniques à discriminer cinq marques de lait pasteurisé marocain. Des limitations du système de nez et de langue électroniques ont été révélées quant à la discrimination du lait pasteurisé (Jawda) en fonction des jours de stockage. Par contre, la fusion des données des deux systèmes moyennant un niveau d'abstraction intermédiaire a permis d’améliorer cette discrimination. Dans une deuxième étape, nous avons développé deux biocapteurs, le premier est basé sur l’utilisation de Polymère à Empreinte Moléculaire (MIP) dédié à la détection de la tétracycline dans le miel. Alors que le second est un immunocapteur conçu pour la détection de l’ochratoxine A. Le MIP, utilisé dans le premier cas, a été synthétisé à la surface d’électrodes en or par électropolymérisation des nanoparticules d'or fonctionnalisées par le p-aminothiophénol en présence de la tétracycline comme molécule empreinte. Dans le deuxième cas, un nouveau biocapteur capacitif basé sur l’utilisation d’un substrat de Nitrure de Silicium (Si3N4) combiné avec une nouvelle structure de nanoparticules magnétiques (MNPs) pour la détection de l’ochratoxine A a été conçu. En effet, Les MNPs possédant une terminaison carboxylique ont été liés de manière covalente à la monocouche auto-assemblée du silane-amine (3-aminopropyl triéthoxysilane APTES). Enfin, les anticorps anti-ochratoxine A ont été immobilisés sur les MNPs par liaison amide. Les performances des deux biocapteurs (limite de détection, sélectivité, reproductibilité) ont ensuite été évaluées
Sensors and Biosensors are rapid, sensitive, selective and low-cost analytical devices of growing interest for a wide range of application fields (e.g. food, environment, health …). This research focused on the development of three devices namely an electronic nose and tongue and electrochemical biosensors with applications in food analysis. The first two devices allowed the characterization and detection of frauds in the food field. Thus, we have been able to detect fraudulent practices in argan oil by using an electronic nose and tongue systems. In addition, the electronic tongue has successfully classified honeys of different geographical and botanical origins and detects the adulteration of pure honey. Finally, we have demonstrated the ability of the electronic nose and tongue systems to classify five brands of Moroccan pasteurized milk and to discriminate against them based on their storage days. In the second stage, we have developed two biosensors. The first one is based on a molecularly imprinted polymer (MIP) for the detection of tetracycline in honey. The second one is based on an immunosensor devoted for the detection of ochratoxin A. For the first biosensor, imprinted gold nanoparticles composites are assembled on Au surfaces by the electropolymerization of p-amino-thiophenol functionalized gold nanoparticles in the presence of the imprint molecule. In the second case, we have developed a novel capacitance electrochemical biosensor based on silicon nitride substrate (Si3N4) combined with a new structure of mangnetic nanoparticles (MNPs). Indeed, The MNPs with terminated carboxylic acid were covalently bonded to Si3N4 through a Self-Assembled Monolayers (SAMs) of the silane-amine (3-Aminopropyl) triethoxysilane (APTES). Finally anti-ochratoxin A antibodies were immobilized on MNPs by amide bonding. The performances of the two biosensors (limit of detection, selectivity, reproducibility) were then evaluated and the results are generally satisfactory

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Sartore, Douglas Morisue. "Microextração de canabinoides em urina usando dispositivo empacotado com polímero molecularmente impresso e análise por cromatografia líquida - espectrometria de massas sequencial." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/75/75135/tde-23102018-171513/.

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O preparo da amostra é uma das etapas mais importantes em toda a análise química. O isolamento e a concentração dos componentes da amostra são cruciais e busca-se sempre que essas etapas sejam as mais simples e consumam o mínimo possível de tempo e reagentes. Nos últimos anos, um tipo de material tem se mostrado bastante útil para análises químicas a partir de fluidos biológicos, os polímeros molecularmente impressos (MIPs). Os MIPs são sintetizados por reações de polimerização, na presença de uma molécula molde (template). A molécula molde se liga aos monômeros funcionais do polímero durante a reação de polimerização e permanece ligada à superfície das cadeias poliméricas quando a reação se completa. Terminada a polimerização, realiza-se a completa lavagem das moléculas molde, assim, restam na superfície polimérica cavidades tridimensionais complementares à molécula empregada como molde. Essas cavidades permitem a ligação reversível e preferencial da molécula molde ou outras com estrutura química semelhante. A Cannabis sativa é a droga ilícita mais consumida em todo o mundo e nos últimos anos muita atenção tem se voltado a seus efeitos toxicológicos no corpo humano e a aplicações medicinais. Nesta dissertação, foi sintetizado um MIP com a molécula molde catequina para a extração e posterior análise por LC-MS/MS dos canabinóides Δ9-tetrahidrocanabinol (THC), 11-hidroxi-Δ9-tetrahidrocannabinol (THC-OH) e 11-nor-Δ9-tetrahidrocannabinol-9-ácido carboxílico (THC-COOH) em amostras de urina. O MIP produzido foi empacotado em microdispositivo e empregado no preparo das amostras de urina por microextração por sorvente empacotado (MEPS). O método desenvolvido apresentou boa linearidade (valores de r de 0,977 para o THC e 0,994 para THC-OH e THC-COOH). Os limites de detecção e de quantificação foram respectivamente de 5 ng mL-1 e 20 ng mL-1, para os compostos THC e THC-OH, na faixa linear de 25 a 250 ng mL-1. Para o composto THC-COOH os limites de detecção e quantificação alcançados foram de 1 ng mL-1 e 5 ng mL-1, respectivamente, na faixa linear de 5 a 170 ng mL-1. O método apresentou valores razoáveis de precisão entre 3,2% (THC-COOH) e 25,1% (THC) e de exatidão, que variou entre -18,4 e 17,4 (ambos para o THC). O MIP empregado no preparo da amostra mostrou-se mais seletivo e específico do que materiais normalmente empregados para a extração dos canabinoides das amostras de urina, além de a técnica de extração por MEPS apresentar baixo consumo de solventes e amostra para a extração dos analitos e posterior análise por LC-MS/MS.
The sample preparation is one of the most important steps in every chemical analysis. The isolation and concentration of the sample components are crucial and it is always sought that these steps are simple and consume the lowest amount of time and reagents. In the recent years, a type of material has proved to be very useful for chemical analyzes of biological fluids, the molecularly imprinted polymers (MIPs). MIPs are synthesized by polymerization reactions in the presence of a template molecule. The template molecule binds to the functional monomers of the polymer during the polymerization reaction and remains bonded to the surface of the polymeric chains after the reaction is complete. After the polymerization is finished, the complete washing of the template molecules is carried out, thus, three-dimensional cavities, complementary to the molecule used as a template, remain on the polymer surface. These cavities allow the reversible and preferential bonding of the template molecule or others with similar chemical structure. Cannabis sativa is the most commonly consumed illicit drug in the world and in recent years much attention has focused on its toxicological effects on human body and for medical applications. In this master dissertation, a MIP was synthesized with the catechin molecule as template, for extraction and subsequent analysis by LC-MS/MS of the cannabinoids Δ9-tetrahydrocannabinol (THC), 11-hydroxy-Δ9-tetrahydrocannabinol (THC-OH), and 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic acid (THC-COOH) in urine samples. The MIP produced was packed in a microdevice and used in the preparation of the urine samples by microextraction by packed sorbent (MEPS). The developed method showed good linearity (r values of 0.977 for THC and 0.994 for THC-OH and THC-COOH). The detection and quantification limits were respectively 5 ng mL-1 and 20 ng mL-1 for THC and THC-OH in the linear range from 25 to 250 ng mL-1. For the compound THC-COOH the limits of detection and quantification achieved were 1 ng mL-1 and 5 ng mL-1, respectively, in the linear range from 5 to 170 ng mL-1. The method presented reasonable values of precision, between 3.2% (for THC-COOH) and 25.1% (for THC) and displayed accuracy ranging from -18.4 to 17.4 (both for THC). The MIP used in the sample preparation was more selective and specific than other materials usually employed for the extraction of the cannabinoids from the urine samples. The MEPS technique also showed low consumption of solvents and sample for sample preparation, extraction of analytes and subsequent analysis by LC-MS/MS.

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17

Silva, Lidya Cardozo da. "Espectrometria de massas por probe electrospray ionization (PESI-MS) com polímero molecularmente impresso (MIP) para determinação de ésteres de forbol em folhas de Jatropha curcas." Universidade Federal de Goiás, 2018. http://repositorio.bc.ufg.br/tede/handle/tede/8813.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
Jatropha curcas L. is a euphorbiaceous oilseed plant considered toxic to humans and animals due to the presence of phorbol esters (PEs). Traditionally, the detection of these toxic compounds has been done in J. curcas seeds and derivates via chromatographic separation methods such as HPLC-UV and HPLC-MS. Although efficient, these techniques are laborious and require high time and solvent consumption, thus it would be interesting the development of new analytical methods to determine these compounds with more practicality. Probe electrospray ionization is frequently used in ambient mass spectrometry allowing analysis with minimum sample preparation. However, for complex samples analysis, this technique presents low sensitivity and ionization suppression. In this study, a molecularly imprinted polymer-coated probe electrospray ionization mass spectrometry (MIPCPESI-MS) method was developed for determination of phorbol esters in methanolic extracts of Jatropha curcas leaves with direct extraction form the ionization source. The synthesized molecularly imprinted polymer (MIP) proved to be adequate for extraction of the PEs in methanolic extracts of J. curcas leaves with better performance as extraction phase in comparison with the non-imprinted polymer (NIP). The MIPCPESI method allowed detection of phorbol 12,13-diacetate (PDA) and other three PEs metabolite ions from Jatropha leaves with minimal sample preparation, and with higher signal intensities compared to analysis with conventional PESI. For the PDA, calibration curve exhibited linearity with R2 > 0.99, LOD and LOQ in µg.mL-1 range, precision and accuracy values, respectively, between 4.06 to 13.49% and -1.60 to -15.26 %. Finally, MIPCPESI was employed for PDA quantification in methanolic extracts of six different J. curcas leaves genotypes resulting in concentrations ranging from 222.19 ± 23.55 to 528.23 ± 19.72 µg.g-1 for toxic samples.
A Jatropha curcas L. é uma oleaginosa euforbiácea considerada tóxica para humanos e animais devido à presença de ésteres de forbol (PEs). Tradicionalmente, a detecção destes compostos tóxicos tem sido feita em tortas e sementes de J. curcas por meio do uso de técnicas de separação cromatográfica como HPLC-UV e HPLC-MS que apesar de eficientes são laboriosas e requerem alto consumo de tempo e solventes. Dessa forma, seria interessante o desenvolvimento de novas técnicas analíticas para determinação desses compostos com maior praticidade. Probe electrosrpay ionization (PESI) é uma das técnicas de ionização utilizadas na espectrometria de massas ambiente que permite análises rápidas com mínimo preparo de amostras. No entanto, para análise de amostras complexas essa técnica apresenta baixa sensibilidade e supressão iônica. Neste estudo, foi desenvolvido um método de análise por espectrometria de massas por Probe electrospray revestido com polímero molecularmente impresso (MIPCPESI-MS) para determinação de ésteres de forbol em extratos metanólicos de folhas de Jatropha curcas com extração direta da fonte de ionização. O polímero molecularmente impresso (MIP) sintetizado mostrou-se adequado para extração de PEs em extratos metanólicos de folhas de J. curcas tendo melhor desempenho como fase extratora quando comparado ao polímero não molecularmente impresso (NIP). O método MIPCPESI-MS possibilitou a detecção do forbol 12,13-diacetato (PDA) e de outros três íons metabólitos presentes nas folhas de J. curcas com mínimo preparo de amostras e com maior intensidade de sinais quando comparado às análises com PESI convencional. Para o PDA, a curva de calibração apresentou linearidade com R2 > 0.99, LOD e LOQ na faixa de µg.mL-1, valores de precisão entre 4.06 e 13.49 % e exatidão entre -1.60 e -15.26 %. Posteriormente, o método MIPCPESI foi empregado na quantificação de PDA em seis extratos metanólicos de diferentes genótipos de folhas de J. curcas resultando em valores concentrações entre 222.19 ± 23.55 a 528.23 ± 19.72 µg.g-1 nas amostras tóxicas.

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Omar, Aouled Nima. "Développement d'un biocapteur associant dispositif à onde de Love et polymères à empreintes moléculaires : caractérisation sous gaz." Phd thesis, Université Sciences et Technologies - Bordeaux I, 2013. http://tel.archives-ouvertes.fr/tel-01064177.

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Ces travaux de recherches concernent l'association de la technologie des polymères à empreintes moléculaires aux dispositifs acoustiques à onde de Love afin de réaliser un biocapteur dans le cadre d'un projet ANR Tecsan. La première partie de ces travaux de thèse a dressé plus spécifiquement la mise au point d'un protocole de dépôt localisé de polymères imprimés (MIP) et non imprimés (NIP) en films minces compatibles avec la propagation de l'onde élastique. La seconde aprtie des travaux a visé une caractérisation des films et des capteurs ainsi réalisés, par microscopie à balayage et apr mesures de détection sous gaz. Des éléments relatifs aux propriétés mécaniques (porosité, surfaces spécifiques) des MIPs et NIPs, avant extraction de la molécule cible, puis après extraction et après recapture, ont permis de valider le principe du capteur, ouvrant la voie à l'application en milieu liquide.

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Lebal, Naîma. "Développement d'architectures innovantes associant capteurs acoustiques et matériaux polymères à empreintes moléculaires pour la détection de biomarqueurs de cancer." Thesis, Bordeaux, 2015. http://www.theses.fr/2015BORD0411/document.

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Les chiffres des statistiques du cancer colorectal en France et dans le mondemontrent la nécessité de développement de plateformes technologiques plus rapides,sensibles et spécifiques pour assurer le diagnostic du cancer. Un diagnostic rapide va ainsiaider à améliorer l’état de santé et réduire le temps d’attente des résultats qui peut être ungrand facteur de stress pour les patients. L’analyse des biomarqueurs dans le sang, lesurines et autres fluides corporels est l’une des méthodes appliquées pour la détectionprécoce de la maladie. Dans le cadre de ce projet des nucléosides urinaires ont été identifiéscomme biomarqueurs pour le cancer colorectal. Financée par l’Agence Nationale de laRecherche (ANR), à travers le projet CancerSensor (programme TECSAN), cette thèse s’estdéroulée au sein de l’équipe MDA (Microsystèmes de Détection Acoustique) du laboratoireIMS. Dans le cadre de ce projet, nous avons proposé une solution technologique dedétection et de suivi de biomarqueurs du cancer colorectal. Notre choix de la stratégie dedétection s’est porté sur les polymères à empreintes moléculaires comme élément dereconnaissance des biomarqueurs. Celui-ci sera associé à un transducteur acoustique àondes de Love mis au point lors de travaux précédents au sein de l’équipe MDA. Lebiocapteur ainsi développé va cibler les nucléosides mis en évidence pour le cancercolorectal
Colorectal cancer statistics in France and all over the world demonstrate theneed for fast, sensitive and specific technological platforms development for cancerdiagnosis. A rapid diagnosis will improve the patients’ health status and reduce the resultswaiting time which could be a great stress factor. Biomarkers analysis in blood, urine andother body fluids is recognized as one of the applied methods for early cancer detection. Inframe of this project, urinary nucleosides have been identified as colorectal cancerbiomarkers. Funded by the National Research Agency (ANR), through the cancer sensorproject (TECSAN program), this thesis was carried out in IMS laboratory. Hence, a colorectalcancer biomarkers detection and monitoring technological solution has been proposed. Inour detection strategy, Molecularly Imprinted Polymers (MIP) has been identified asbiomarker recognition element. The MIP layer has been associated to Love Wave acoustictransducer. This biosensor will sense the identified colorectal cancer nucleosides

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Li, Bin. "Molecularly imprinted polymers for applications in cosmetology." Thesis, Compiègne, 2013. http://www.theses.fr/2013COMP2083.

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Un polymère à empreintes moléculaires (MIP) est un récepteur synthétique supramoléculaire, un matériau possédant des cavités pouvant reconnaître spécifiquement une molécule cible. Il est synthétisé en mettant en contact la molécule cible, avec un mélange de monomères fonctionnels et réticulants qui permettent d'obtenir un réseau polymérique tridimensionnel rigide. L'élimination de la molécule empreinte laissera des sites vides complémentaires de cette dernière. Ces cavités sont maintenant capables de la recapturer spécifiquement. Ces polymères sont utilisés dans les domaines tels que l’extraction en phase solide, la chromatographie d’affinité, la catalyse enzymatique, les biocapteurs et la vectorisation des médicaments. Bien que le concept des MIPs a pour origine les travaux réalisés sur des matériaux sol-gel imprimés dans les années 1930, ces derniers sont restés dans l’ombre jusqu’à l'introduction de polymères organiques imprimés plus versatiles. Par rapport aux MIPs organiques, les MIPs sol-gel présentent quelques avantages comme une plus grande stabilité thermique, une meilleure compatibilité avec l'eau et une plus grande porosité. Dans cette thèse, nous avons développé des MIPs organiques et des MIPs sol-gel pour leur application en cosmétologie et pour la vectorisation de médicaments. Dans la première partie, nous présentons des MIPs pouvant adsorber d’une façon spécifique l’acide oléique (OA), un biomarqueur de l’état pelliculaire sur le cuir chevelu. Pour la préparation des MIPs organiques, nous avons employé plusieurs monomères basiques dont l’acryloylaminobenzamidine (AB), que nous avons tout spécialement synthétisé. Tous les MIPs pouvaient lier l’OA mais beaucoup d’interaction non-spécifique était observé. D’autre part, les MIPs sol-gel présentaient une bonne reconnaissance spécifique et une capacité élevée pour OA; par exemple, un MIP de composition OA:APTES:TEOS = 1:1.6:1.7 pouvait adsorber 625 μmol.g-1 de OA dans le sébum artificiel. Des tests pour capturer l’OA sur le stratum corneum et la peau reconstruite (Episkin) ont également été effectués. La pénétration de l’OA sur les deux types de peau était plus faible en présence de MIP que de NIP. Les MIPs comme matériaux désodorisants font l’objet de la deuxième partie de cette thèse. Des MIPs pouvant adsorber les précurseurs de molécules malodorantes comme les conjugués glutamine des acides (E)-3-méthyl-2-hexénoïque (3M2H) et 3-hydroxy-3-méthyl-hexanoïque (3H3MH) ont été préparés. Le N-hexanoyl glutamine et le N-hexanoyl glutamate ont été utilisés comme template. Nous observons que le MIP synthétisé avec AB comme monomère fonctionnel possède la plus grande capacité d'adsorption pour le N-hexanoyl glutamine, ainsi que pour les précurseurs glutamines des molécules malodorantes. Des résultats préliminaires et très prometteurs ont également été obtenus dans la sueur. La dernière partie de cette thèse concerne des MIPs pour la vectorisation de médicaments. L'acide salicylique (SA) est un médicament efficace utilisé dans le traitement de l’acné. Des MIPs organiques et sol-gel contre SA ont été synthétisés. Les MIPs sol-gel ont une plus grande capacité d’adsorption, 180 μmol.g-1, que les MIPs organiques et ils lient le SA sept fois plus que le NIP. Les tests de relargage du SA ont été effectués dans plusieurs milieux, avec la plus grande efficacité dans l’eau pure. En conclusion, les applications de MIPs en cosmétologie et en vectorisation de médicaments ont étés étudiés. Nos résultats montrent que les MIPs sol-gel sont les plus appropriés pour ce type de travail
Molecularly imprinted polymers (MIPs) are tailor-made synthetic receptors possessing specific cavities for a given target molecule. They are produced by introducing, into the polymer precursors, guest molecules that act as templates at the molecular level. Interacting and cross-linking monomers are then copolymerized to form a cast-like shell. After removal of the template, cavities complementary to the template in size, shape and position of functional groups are revealed in the polymer, which can now specifically bind the template. Thanks to these specific molecular recognition properties, MIPs have found applications in areas like bio sensors, solid phase extraction, affinity chromatography, catalysis, and drug delivery. Although the MIP concept originated from imprinted silica in the 1930s, imprinted sol-gel materials received little attention afterwards due to the introduction of the more versatile organic polymers as imprinting matrix. However, compared to organic polymers, sol-gels possess higher thermal stability, better water compatibility and larger inner surface area. There have been many applications to biomolecules in aqueous conditions with sol-gel imprinting materials. In this thesis, we have developed organic and silica sol-gel MIPs for applications in cosmetics and drug delivery. MIPs able to adsorb the dandruff-inducing molecule oleic acid (OA) were produced via both the organic and inorganic routes. In the organic MIPs synthesis, different positively charged monomers were used, one of which, acryloyl aminobenzamidine, was specifically synthesized. Although some binding of oleic acid was obtained, specificity and capacity of these polymers were not satisfying. Sol-gel MIPs, on the other hand, exhibited good specific recognition and high binding capacity for OA. A MIP of the composition OA:APTES:TEOS= 1:1.6:1.7 yielded a capacity of 625 μmol.g-1 in artificial sebum. Furthermore, tests were carried out to capture OA on stratum corneum and reconstructed skin (Episkin). Less penetration of OA was observed in the presence of a MIP than with a non-imprinted control polymer. Deodorant materials are another topic of this thesis. MIPs that are able to adsorb certain precursors of odorant molecules, the glutamine conjugates of (E)-3-methyl-2-hexenoic acid (3M2H) and 3-hydroxy-3-methyl-hexanoic acid (3H3MH) were prepared. N-hexanoyl glutamine and N-hexanoyl glutamate were used as templates. After optimization of the MIP composition, we found that MIPs synthesized with acryloyl aminobenzamidine as functional monomer had the highest adsorption capacity for N-hexanoyl glutamine, and also recognised the glutamine targets of 3M2H and 3H3MH. Some preliminary promising binding results were obtained in artificial sweat. The third part of this work concerns a drug delivery MIP. Salicylic acid (SA) is a drug used to treat acne. SA-imprinted polymers were prepared via both organic imprinting and the sol-gel process.Compared to organic MIPs, sol-gel MIPs have a higher capacity, 180 μmol.g-1, and 7 times higher binding than to a non-imprinted control polymer was observed. Release tests were carried out in different aqueous media, the most efficient drug release was observed in pure water. In conclusion, applications of molecularly imprinted polymers for cosmetics and drug delivery have been investigated. Our results demonstrate the great potential of in particular sol-gel MIPs for these purposes

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Leibl, Nadja. "Development of molecularly imprinted polymers for chemical sensors." Thesis, Compiègne, 2018. http://www.theses.fr/2018COMP2446.

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Cette thèse propose une approche rationnelle pour le design de polymères à empreintes moléculaires (MIPs) pour la détection de nitro-explosifs. Les polymères à empreintes moléculaires qui miment la reconnaissance moléculaire biologique, ont l’avantage d’être stables dans des environnements sévères et peuvent adopter différentes formes physiques pour le couplage avec des transducteurs. Leur synthèse est basée sur la co-polymérisation de monomères fonctionnels et réticulants en présence de la molécule cible, ou comme dans cette thèse, d’un analogue ayant une structure proche de celle de la molécule cible. Cela conduit à la formation d’un réseau polymérique tridimensionnel rigide avec des sites de liaison complémentaires en taille, forme et position des groupes fonctionnels de la molécule cible ou de l’analogue. Pour identifier le meilleur monomère fonctionnel pour notre molécule cible, une approche rationnelle basée sur la modélisation moléculaire, la résonance magnétique nucléaire (RMN) et le titrage par calorimétrie isotherme (ITC) a été utilisée. Elle permet d’optimiser le mélange de pré-polymérisation pour identifier le monomère fonctionnel interagissant le plus fortement avec la molécule cible. Les résultats obtenus ont été confrontés à des études de liaison à partir de polymères synthétisés. La formulation polymérique ainsi conçue est intégrée aux surfaces du transducteur sous forme de nanoparticules, de films et de nanoparticules incorporés dans des films de polydopamine électropolymérisés. En plus des polymères traditionnels obtenus par polymérisation radicalaire classique sous forme de particules, des films de MIP à base de polydopamine électropolymérisés ont été étudiés en tant qu'approche alternative pour la détection électrochimique de nitro-explosifs
This thesis proposes a rational design approach towards molecularly imprinted polymers (MIPs) for sensing nitro-explosives. Molecularly imprinted polymers are mimicking biological molecular recognition. They have the advantage to be stable in harsh environments and can be tailored into different physical forms for interfacing with transducers. Their synthesis is based on the co-polymerization of functional and cross-linking monomers in the presence of the target analyte or, as in this thesis, with a structural analogue leading to a rigid three-dimensional polymer network with binding sites complementary to the template in size, shape and position of the functional groups. The choice of the functional monomer was carried out with a rational design approach combining molecular modelling, nuclear magnetic resonance (NMR) and isothermal calorimetry (ITC) studies. This allows to optimize the pre-polymerization mixture in order to get strong complexation between the functional monomer and the template. The obtained results were confronted with binding studies performed on synthesized polymers. The thus designed polymer formulation was interfaced with transducer surfaces in form of nanoparticles, films and nanoparticles embedded into electro-polymerized polydopamine films. In addition to the traditional MIPs by free radical polymerization, molecularly imprinted in-situ electro-polymerized polydopamine films were investigated as an alternative approach for sensing nitro-explosives electrochemically

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Zhao, Yi. "Degradable molecularly imprinted polymers-synthetic antibody mimics for the vectorization of active molecules." Thesis, Compiègne, 2015. http://www.theses.fr/2015COMP2189.

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Les polymères à empreintes moléculaires (MIP) sont des matériaux synthétiques capables de mimer les anticorps biologiques. En effet, ils possèdent deux des principales caractéristiques de ces derniers, à savoir : la capacité de reconnaître et de se lier spécifiquement à des molécules cibles. De plus, leur synthèse facile, leur bas coût de production, leur haute spécificité et stabilité par rapport aux anticorps naturels font des MIP une alternative intéressante. En effet, les propriétés de reconnaissance moléculaire des MIP permettent d'envisager leur utilisation dans une vaste gamme d’applications. Ils sont ainsi largement exploités dans les sciences séparatives pour l'analyse d'échantillons environnementaux ou agro-alimentaires, ou comme élément de reconnaissance dans des biocapteurs. Récemment, des applications de ces matériaux dans les domaines biologiques et biomédicaux ont émergé comme pour la détection, l'extraction et l"élimination de molécules indésirables dans l'organisme, la vectorisation ou l'administration contrôlée des médicaments. Dans nos recherches, nous avons développé des MIP dégradables par voie biochimique ou enzymatique, ayant une application potentielle en tant que système de libération contrôlé de molécules. En général, les MIPs sont synthétisés par polymérisation radicalaire libre en utilisant une formulation composée de monomères fonctionnels, d'agents de réticulation, et d'une molécule cible servant à réaliser l'empreinte moléculaire. Dans ce travail de thèse, nous avons utilisé pour la synthèse de MIP dégradable des agents de réticulation clivables contenant, soit une fonction chimique dégradable par voie chimique ou enzymatique (ponts disulfures et phosphatediester), soit un disaccharide issus d'agro-ressources et pouvant être naturellement hydrolysé par des enzymes. En présence d'un réactif spécifique (agent réducteur ou enzyme), les liaisons dites "sensibles" aux réactifs chimiques ou enzymatiques peuvent être clivées, ce qui entraîne une dégradation de la matrice polymérique. Le polymère perdra alors sa capacité de reconnaissance et de liaison à la molécule cible et permettra la libération de celle-ci. Nous pensons donc, que les nouveaux MIP dégradables pourraient avoir un énorme potentiel comme vecteurs "intelligents" dans des applications médicales tels que les systèmes de libération contrôlée de médicament. Finalement, nous avons étudié la dégradation par des microorganismes de la structure de base de ce type de polymères, en utilisant comme modèles des chaines linéaires et réticulées
Molecularly imprinted polymers (MIPs) are biomimetic synthetic receptors that possess two of the most important features of biological antibodies – the ability to recognize and bind specific target molecules. Owing to their easier preparation, lower cost, higher specifity and stability compared to antibodies, they have the potential to be widely applied for environemental and food analysis. Recently, MIPs also emerged in the biochemical field as diagnostic tools, chemicals traps to remove undesirable substance from the body, or drug delivery systems, where usually the combination of biocompatibility and degradability after its use is desirable. Here, we developed biochemically or enzymatically degradable MIPs, which have potential applications as activation-modulated drug delivery systems. In general, MIPs are prepared by radical polymerization of functional monomers and cross-linkers in the presence of a target molecule acting as template. Degradable MIPs were synthesized using cleavable cross-linkers containing a degradable group (disulfide bond or phosphate ester bond) or derived from a natural disaccharide. In the presence of a cleaving reagent (reducing agent or enzyme), the chemo or enzyme-sensitive bond could be cleaved, resulting in the degradation of the polymer matrix. The degraded polymers looses the binding sites structure resulting in the loss of recognition and binding capacity towards the target molecules, and thus in the release of bound molecules. These degradable MIPs provide new opportunities as “smart” vectors for controlled delivery of active molecules in biomedical applications. Finally, the biodegradation of the polymer backbone by bacteria was investigated

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Alshareef, Fatmah. "Construction and Evaluation of Novel Molecularly Imprinted Polymers (MIPs) Using Helical Poly(3-Methyl-4-Vinylpyridine)." DigitalCommons@Robert W. Woodruff Library, Atlanta University Center, 2017. http://digitalcommons.auctr.edu/cauetds/104.

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A novel chiral helical imprinted polymer (MIP) has been prepared by bulk copolymerization of 3-methyl-4-vinylpyridine and a crosslinker using chiral S-mandelic acid as template. The resulting MIPs after removing the template show optical activity that is derived from the presence of chiral helical structures of poly(3-methyl-4-vinylpyridine) (P3M4VP) embedded within the MIP matrix. The basic functional monomer 3-methyl-4-vinylpyridine (3M4VP) was utilized with the acidic template to ensure good interaction between the template and the polymer. Divinylbenzene (DVB) and ethyleneglycoldimethacrylate (EGDMA) with widely varying degree of rigidity, flexibility, and polarity were selected as crosslinking agents. Using two different crosslinkers, it was possible to optimize the MIP for maximum specificity and selectivity. Spectroscopic methods such as FT-IR and 1H NMR were used to investigate the interaction between template and functional monomer. Scanning electron microscopy and nitrogen sorption analysis showed significant difference of the surface morphological characteristics between imprinted and non-imprinted polymers. Thermogravimetric analysis (TGA) was carried out to investigate thermal stability of MIPs and NIPs. The binding studies and the selectivity of the polymers were analyzed using UV-visible spectroscopy. The chiral secondary or higher structural ordering within the MIPs was examined using circular dichroism (CD) spectrometry. The polymer preparations were evaluated and compared with non-imprinted polymers for their ability to bind the template which is a measure of the specificity of the imprinted system. The nature and degree of crosslinking and other parameters like concentration of the template solution, solvent, and time which influences the binding of these imprinted polymers towards the print molecule were also investigated to optimize the imprinted system. The ability of the S-enantiomer imprinted polymer to bind the R-enantiomer was investigated. The separation and selectivity factors have been quantified. The present study develops a successful strategy for preparing chiral MIPs, which are expected to find vital applications in chiral separation, and enantioselective release of chiral drugs.

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Çakir, Pinar. "Molecularly imprinted polymer nanostructures by controlled / living radical polymerization with multi-iniferters." Compiègne, 2012. http://www.theses.fr/2012COMP2018.

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Les polymères à empreintes moléculaires (MIPs) sont des matériaux synthétiques contenant des cavités capables de reconnaître spécifiquement une molécule cible. Ils se présentent comme une alternative intéressante face aux anticorps biologiques en raison de leur meilleure stabilité chimique et physique, leur meilleure disponibilité et leur moindre coût. Traditionnellement, les MIPs sont synthétisés par polymérisation de monolithes, qui sont ensuite broyés mécaniquement, engendrant des particules de taille micrométrique et de formes irrégulières. Durant ces dernières années, de nombreuses techniques de polymérisation ont été développées afin d’obtenir des particules MIP sphériques de tailles micro et nanométriques, et plus particulièrement des nanogels quasi-solubles. Dans l’optique d’une application en biologie, des tailles de quelques nanomètres - de l’ordre de grandeur de la taille des protéines – sont souhaitées, ce qui pose un réel défi pour leur synthèse, car la faible densité du matériau (une particule ne consiste que de quelques chaines de polymère) s'oppose à l'impression d'une mémoire moléculaire. Nous avons développé une nouvelle approche de synthèse de MIP nanogels dont la taille est proche de celle des anticorps naturels. Notre stratégie est basée sur l’utilisation d’un nouveau type d'amorceur pour la polymérisation radicalaire contrôlée comprenant des fonctions iniferter multiples attachées à un noyau dendritique. Cela permet de générer une concentration localement élevée de radicaux et ainsi, d'obtenir des nanogels de polymère dont la densité est augmentée. Ces travaux de thèse ont conduit à l’obtention des nanogels de MIP de 17 nm de diamètre avec un effet impression appréciable, une bonne affinité pour la cible, le beta-antagoniste propranolol, et une sélectivité moléculaire prononcée. En plus de la synthèse des nanogels solubles de MIP, des motifs de MIP micro et nanostructurés ont été greffés sur des surfaces planes de silicium. Le multiiniferter a été imprimé à la surface par lithographie douce, et fixé chimiquement par son groupement carboxyle central. Les MIPs ont ensuite été synthétisés par une approche « bottom up », caractérisés par spectroscopie d'émission optique, la spectroscopie Raman et la microscopie à force atomique, et la reconnaissance moléculaire de la cible a été visualisée par microscopie de fluorescence. Ces nouveaux matériaux, nanogels et surfaces imprimées offrent de nombreuses perspectives pour la détection par biocapteurs et biopuces, en particulier dans le domaine du biomédical
Molecularly imprinted polymers (MIPs) are synthetic materials with specific recognition properties for target molecules. They are considered an alternative to antibodies and are characterized by a higher chemical and physical stability, better availability and lower cost. Historically, MIPs were synthesized as bulk monoliths that were subsequently broken down mechanically in order to form particles of a size in the micrometer range, with irregular shapes. During the last decade, research has focused on the direct synthesis of spherical MIP micro and nanoparticles, and, more recently, on protein-sized, quasi-soluble MIP nanogels in order to widen the application range of MIPs in the biological field. The main difficulty of synthesizing MIPs with diameters in the low nm region is the low density of the resulting polymer network consisting only of a few polymer chains, which makes it difficult to imprint and maintain a molecular memory. In this thesis, we propose an original approach to the synthesis of quasisoluble MIP nanogels with a size in the low nm range, close to that of real antibodies. The proposed procedure involves a new type of initiator for controlled/living radical polymerization, based on multiple iniferter moieties attached to a dendritic core. This allows for the generation of a higher local radical density, and thus for the synthesis of denser nanogels. By using this strategy, MIP Nanogels of 17 nm size with an appreciable molecular imprinting effect, a good affinity for the target molecule, the chiral drug propranolol, and a good selectivity were obtained. In addition, these multiiniferters were also used for the bottom-up synthesis of thin MIP patterns on silicon wafers, by surface-initiated polymerization. The multi-iniferter was printed on to the surface by soft lithography and chemically attached through its carboxyl-functionalized core, followed by the in-situ synthesis of the MIP. Well defined MIP patterns were obtained, which were characterized by optical emission spectroscopy, Raman spectroscopy, atomic force microscopy, and the specific binding of the target molecule was visualized by fluorescence microscopy. We believe that the synthesis, in solution and at surfaces, of protein-size MIP nanogels with specific recognition properties will provide new opportunities for biosensors and biochips technologies in biomedical applications

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Figueiredo, Eduardo Costa de. "Emprego de polimeros de impressão molecular (MIP) na extração e pre-concentração de analitos organicos em amostras biologicas seguido de determinação espectrofotometrica." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/248589.

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Orientador: Marco Aurelio Zezzi Arruda
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Quimica
Made available in DSpace on 2018-08-12T19:20:38Z (GMT). No. of bitstreams: 1 Figueiredo_EduardoCostade_D.pdf: 6808404 bytes, checksum: 000ecbe23739fa5d1c64af83061c6da5 (MD5) Previous issue date: 2009
Resumo: Essa Tese de Doutorado teve como objetivo promover a associação entre polímeros de impressão molecular (MIP) e espectrofotometria, sendo a seletividade conseguida pela ligação específica dos analitos com os sítios de reconhecimento molecular impresso no MIP. No capítulo 1 foi sintetizado e caracterizado um MIP seletivo a catecol, sendo o mesmo empregado na extração de catecol em amostras de guaraná (Paullinia cupana) e mate (Ilex paraguariensis), seguido de determinação espectrofotométrica (reação não específica de redução de Mn(VII) para Mn(II) pelo catecol). Obteve-se um limite de quantificação, um desvio padrão relativo (20 mmol L, n=10) e uma freqüência analítica de 2,7 mmol L, <5% e 15h, respectivamente. A exatidão foi comprovada por comparação dos resultados obtidos pelo método proposto e por HPLC. No Capítulo 2 um MIP foi empregado na extração de nicotina em amostras de urina de fumantes, seguido da quantificação por espectrofotometria (reação de redução do Mn(VII) a Mn(VI)). O limite de quantificação e a freqüência analítica foram de 1,1 mmol L e 11 h, respectivamente. As precisões intra-ensaio (10, 13 e 4%) e inter-ensaio (12, 10 e 5%) foram obtidas empregando-se padrões de 3, 10 e 30 mmol L, respectivamente e a exatidão foi comprovada por meio da técnica de HPLC. No capítulo 3 foi reportado o emprego do MIP na extração de fármacos fenotiazínicos (clorpromazina e perfenazina) em amostras de urina de pacientes. Após a extração, os fármacos foram eluidos e separados, à baixa pressão e alta velocidade, em uma coluna de C18 com tamanho de partícula entre 35 e 50 mm. Os limites de quantificação foram de 5 mmol L, para ambos os fármacos, e a exatidão foi comprovada por adição de analitos e pela técnica de HPLC
Abstract: The objective of this Thesis was the association between molecularly imprinted polymers and spectrophotometry, with the selectivity obtained through specific binding between analytes and imprinted binding sites of the polymer. In the Chapter 1, a selective MIP for catechol was synthesized, characterized, and employed for the extraction of catechol from guarana (Paullinia cupana) and mate (Ilex paraguariensis) samples, followed by indirect spectophotometric determination of catecol by reduction of Mn(VII) for Mn(II). A limit of quantification, a relative standard deviation (20 mmol L, n = 10) and an analytical frequency of 2.7 mmol L, <5% and 15h, were obtained, respectively. Accuracy was validated using HPLC. In the Chapter 2, a MIP for nicotine was used for its extraction in urine samples of smokers, followed by its indirect quantification by spectrophotometry (reduction of Mn(VII) to Mn(VI) by nicotine). The limit of quantification and analytic frequency were of 1.1 mmol L and 11 h, respectively. Intra (10, 13 and 4%) and inter-day (12, 10 and 5%) precisions were obtained using 3, 10 and 30 mmol L nicotine standard solutions, respectively, and accuracy was validated through HPLC. Finally, in the Chapter 3, a MIP was employed for phenothiazinics (chlorpromazine and perphenazine) extraction in urine samples. Soon after, the drugs were eluted and separated using a low pressure and high-speed system, comprising a C18 column with particle size between 35 and 50 mm. The quantification limits were 5 mmol L for chlorpromazine and perphenazine, and the accuracy was validated using HPLC
Doutorado
Quimica Analitica
Doutor em Ciências

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Rajkumar, Rajagopal. "Development of a thermometric sensor for fructosyl valine and fructose using molecularly imprinted polymers as a recognition element." Phd thesis, Universität Potsdam, 2007. http://opus.kobv.de/ubp/volltexte/2008/1727/.

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Nature has always served as a model for mimicking and inspiration to humans in their efforts to improve their life. Researchers have been inspired by nature to produce biomimetic materials with molecular recognition properties by design rather than evolution. Molecular imprinting is one way to prepare such materials. Such smart materials with new functionalities are at the forefront of the development of a relevant number of ongoing and perspective applications ranging from consumer to space industry. Molecularly imprinted polymers were developed by mimicking the natural enzymes or antibodies that serve as host for binding target molecules. These imprints were used as a recognition element to substitute natural biomolecules in biosensors. The concept behind molecular imprinting is to mold a material (with the desired chemical properties) around individual molecules. Upon removal of the molecular templates, one is left with regions in the molded material that fit the shape of the template molecules. Thus, molecular imprinting results in materials that can selectively bind to molecules of interest. Imprinted materials resulted in applications ranging from chemical separation to bioanalytics. In this work attempts were made particularly in the development of molecularly imprinted polymer based thermometric sensors. The main effort was focused towards the development of an covalently imprinted polymer that would be able to selectively bind fructosyl valine (Fru-Val), the N-terminal constituent of hemoglobin A1c ß-chains. Taking into account the known advantages of imprinted polymers, e.g. robustness, thermal and chemical stability, imprinted materials were successfully used as a recognition element in the sensor. One of the serious problems associated with the development of MIP sensors and which lies in the absence of a generic procedure for the transformation of the polymer-template binding event into a detectable signal has been addressed by developing the "thermometric" approach. In general the developed approach gives a new insight on MIP/Analyte interactions.
In dem Bestreben, ihr eigenes Leben zu verbessern, haben die Menschen stets die Natur nachgeahmt und sich von ihr inspirieren lassen. Die Natur hat Forscher zur Erzeugung smarter biomimetischer Stoffe mit molekularen Erkennungseigenschaften nach dem Vorbild der Evolution inspiriert. Eine der Methoden zur Herstellung solcher Substanzen ist das molekulare Prägen. Smarte Materialien mit neuen Eigenschaften stehen an der Spitze der Entwicklung potentieller Anwendungen vom Verbraucher bis hin zur Raumfahrtindustrie. Durch Nachahmung von natürlichen Enzymen oder Antikörpern wurden molekular geprägte Polymere (MIPs) entwickelt, die der Bindung von Zielmolekülen dienen. Diese geprägten Polymere (imprints) wurden anstelle von Biomolekülen als Erkennungselemente in Biosensoren eingesetzt. Das Konzept, das dem molekularen Prägen zugrunde liegt, besteht in der Formung eines Polymers (mit den entsprechenden chemischen Eigenschaften) um einzelne Zielmoleküle herum. Nach Entfernen dieser molekularen Template bleiben Abdrücke im Polymer übrig, die der Form der Templatmoleküle entsprechen. Mit Hilfe des molekularen Prägens kann man also Stoffe herstellen, die sich selektiv an bestimmte Moleküle binden können. Geprägte Polymere finden breite Anwendung, etwa in chemischen Aufreinigungsprozessen und der Bioanalytik. Hauptanliegen der vorliegenden Arbeit war es, thermometrische Sensoren auf der Basis molekular geprägter Polymere zu entwickeln. Die Anstrengungen richteten sich vor allem auf die Entwicklung eines kovalent geprägten Polymers, das in der Lage ist, selektiv Fruktosyl-Valin (Fru-Val), den N-terminalen Bereich von Hämoglobin A1c, zu binden. Aufgrund der bekannten Vorzüge geprägter Polymere – z. B. Robustheit und thermische und chemische Stabilität – wurden geprägte Polymere erfolgreich als Erkennungselement im Sensor angewendet. Eine der größten Herausforderungen bei der Entwicklung von MIP-Sensoren, das Fehlen eines generischen Verfahrens zur Umwandlung der Bindungsreaktion in ein nachweisbares Signal, wurde mit der Entwicklung der thermometrischen Methode in Angriff genommen. Diese Methode führt allgemein zu neuen Einsichten in die Interaktionen zwischen MIP und Analyt.

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Ton, Xuan-Anh. "Fiber optic chemical sensors based on molecularly imprinted polymers for the detection of mycotoxins." Phd thesis, Université de Technologie de Compiègne, 2013. http://tel.archives-ouvertes.fr/tel-01002117.

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This thesis describes the development of highly selective fiber optic sensors using molecularly imprinted polymers (MIPs) as recognition elements associated with fluorescence for detection. Additionally, we extended the study to the development of other MIP-based optical sensors and sensing methods. MIPs are synthetic biomimetic receptors possessing specific cavities designed for a target molecule. Produced by a templating process at the molecular level, MIPs are capable of recognizingand binding target molecules with selectivities and affinities comparable to those of natural receptors. Compared to biological recognition elements, MIPs are more stable, cheaper and easier to integrate into standard industrial fabrication processes. Hence, MIPs have become interesting alternatives to biomolecules as recognition elements for biosensing. In the first part of this thesis (Chapter 2), MIPs were synthesized by in-situ laser-induced photopolymerization in only a few seconds, as a micrometer-sized tip at the extremity of a telecommunication optical fiber. Photonic and physico-chemical parameters were optimized to tailor the properties of the polymer micro-objects. Gold nanoparticles were incorporated into the MIP microtip for signal enhancement. To prove the efficiency of the sensor, initial studies were performed with a MIP templated with N-carbobenzyloxy-L-phenylalanine (Z-L-Phe) and the fluorescent amino acid derivative dansyl-L-phenylalanine as analyte. The fluorescence was collected either externally at the tip level by an optical fiber connected to a spectrofluorimeter or by collection of the fluorescent signal re-emitted into the fiber through the second arm of a Y-shaped bifurcated fiber. The fluorescent analyte could be detected in the low nM concentrations. In order to monitor nonfluorescent analytes, a naphthalimide-based fluorescent monomer was incorporated into the MIP during its synthesis; fluorescence enhancement was observed when analyte binding occurs. Using this system, the sensor containing a MIP specific for the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D), could detect and quantify this analyte at concentrations as low as 2.5 nM. The signaling MIP-based sensor was also applied to analytes of interest for food safety and biomedical applications, such as the mycotoxin citrinin and the sphingolipid, D-erythro-sphingosine-1-phosphate. In the second part of the thesis (Chapter 3), a different type of fiber optic sensor: cheap, fast and made for "single-use", was developed by using 4-cm long disposable polystyrene evanescent wave optical fiber waveguides. The coating of the MIP was either performed ex-situ, by dip-coating the fiber in a suspension of MIP particles synthesized beforehand, or in-situ by evanescent-wave photopolymerization directly on the fiber. The resulting fiber optic sensor could detect 2,4-D in the low nM range and demonstrated specific and selective recognition of the herbicide over its structural analogues and other non-related carboxyl-containing analytes. Additionally, we demonstrated the versatility of the system by applying the evanescent wave fiber optic sensor to detect citrinin, a mycotoxin, by simply coating the waveguide with a MIP specific for citrinin. This type of technology could possibly be extended to detect other carboxyl-containing analytes, as long as a specific MIP for the concerned analyte is available. In parallel, the technique of evanescent-wave photopolymerization was used for the synthesis of signaling MIP microdots on continuous and nanostructured gold films. This study lays the foundations for future development of plasmonic MIP nanosensors and microchips. In the last part of the thesis (Chapter 4), an innovative sensing method, based on the use of MIPs and analysis by fluorescence polarization, was developed in order to allow the fast and directquantification of analytes in food and environmental samples.

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Aftim, Nadin. "Polymères à empreinte moléculaire pour l'extraction d'un insecticide organophosphoré utilisé en oléiculture : le phosmet." Thesis, Perpignan, 2017. http://www.theses.fr/2017PERP0030.

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L’objectif de cette thèse a consisté en la synthèse d’un polymère à empreinte moléculaire (MIP) permettant l’extraction du phosmet, un pesticide organophosphoré largement utilisé en oléiculture. La recherche du monomère fonctionnel (MF) disposant de la meilleure capacité à interagir de manière non-covalente avec le phosmet en présence du solvant porogène le plus approprié a été réalisée pour la toute première fois au moyen d’un capteur à acétylcholinestérase. Cette stratégie innovante a permis une meilleure compréhension des mécanismes cinétiques à l’œuvre lors de l’interaction MF-molécule cible. De par l’importance de son rôle dans la détermination de la structure d’un MIP, le choix d’un agent réticulant aux caractéristiques physico-chimiques adéquates a permis de sélectionner le meilleur MIP en s’appuyant sur l’étude des isothermes d’adsorption selon les modèles de Freundlich et Langmuir. La procédure d’extraction du phosmet selon la procédure MISPE (Molecularly Imprinted Solid Phase Extraction) a été effectuée par le biais d’une cartouche SPE dont la capacité a été évaluée à partir d’une solution standard. La validation du choix des réactifs de MIP sélectionnés a été confortée par la réalisation d’une expérience de réactivité croisée appliquée à une molécule analogue au phosmet. L’extraction du phosmet de l’huile d’olive a pu être effectuée avec succès selon un protocole d’extraction en flux inverse optimisé. Cette étude ouvre ainsi la voie à la recherche de nouvelles interactions MFs-molécules cibles au moyen de biocapteurs enzymatiques inhibant des composés toxiques tels que les herbicides, fongicides et autres pesticides
The objective of this thesis has been the synthesis of a molecularly imprinted polymer (MIP) for the extraction of phosmet, an organophosphorus pesticide widely used in olive growing. The search for the functional monomer (FM) having the best ability to interact non-covalently with phosmet in the presence of the most suitable pore-forming solvent was carried out for the first time by means of an acetylcholinesterase sensor. This innovative strategy allowed us to better understand the kinetic mechanisms of FM-template interaction. Because of the importance of its role in determining the structure of a MIP, the selection of a crosslinking agent with adequate physicochemical characteristics made it possible to select the best MIP, whose adsorption isotherms were studied according to Freundlich and Langmuir models. Extraction of phosmet using a Molecularly Imprinted Solid Phase Extraction (MISPE) procedure was carried out via an SPE cartridge, whose capacity was evaluated from a standard solution. The choice of reagents and experimental conditions were validated by carrying out selectivity assays using another organophosphorus insecticide. Extraction of phosmet from olive oil was successfully carried out according to an optimized reverse flow extraction protocol. This work opens new opportunities for studying new FM-template interactions by means of enzymatic biosensors capable of detecting other inhibitors such as herbicides, fungicides and other pesticides

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Bergman, Nina. "Sample preparation of 8-hydroxy-2’-deoxyguanosine with solid phase extraction methodology based on molecular imprinting polymers and conventional silica based phases." Thesis, Linköpings universitet, Institutionen för fysik, kemi och biologi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-71325.

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The aim of this study was to develop methods for sample preparation for 8-OHdG in blood plasma samples with different solid phase extraction techniques using HPLC with an elec- trochemical detector. The solid phase extraction cartridges used were Chromabond® C18, Oasis® MAX, and three types of SupelMIPTM cartridges for chloramphenicol, riboflavin, and nitroimidazoles. The SupelMIPTM cartridges are based on molecularly imprinted polymers- technique. The separation of 8-OHdG in samples extracted from blood plasma was carried out with a Thermo Quest Hypersil Division ODS column (250 mm × 4 mm, 3μm I.D.) and methanol:buffer (10:90, v/v) as mobile phase. Recovery and selectivity was studied for the different solid phase extraction methods. The highest recovery was obtained using the Chromabond C18 cartridge with a recovery of 92%, and CV coefficient 9.5% (n = 4). 8-OHdG could not be extracted on MIP-cartridges for chloramphenicol or riboflavin, but was retained on MIP columns for nitroimidazoles, and the highest recovery was 49%.

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Brahmbhatt, H. A., Alexander P. H. Surtees, C. Tierney, O. A. Ige, E. V. Piletska, Thomas Swift, and N. W. Turner. "Effect of polymerisation by microwave on the physical properties of molecularly imprinted polymers (MIPs) specific for caffeine." Royal Society of Chemistry, 2020. http://hdl.handle.net/10454/18143.

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Yes
Molecularly Imprinted Polymers (MIPs) are a class of polymeric materials that exhibit highly specific recognition properties towards a chosen target. These “smart materials” offer robustness to work in extreme environmental conditions and cost effectiveness; and have shown themselves capable of the affinities/specificities observed of their biomolecular counterparts. Despite this, in many MIP systems heterogeneity generated in the polymerisation process is known to affect the performance. Microwave reactors have been extensively studied in organic chemistry because they can afford fast and well-controlled reactions, and have been used for polymerisation reactions; however, their use for creating MIPs is limited. Here we report a case study of a model MIP system imprinted for caffeine, using microwave initiation. Experimental parameters such as polymerisation time, temperature and applied microwave power have been investigated and compared with polymers prepared by oven and UV irradiation. MIPs have been characterised by BET, SEM, DSC, TGA, NMR, and HPLC for their physical properties and analyte recognition performance. The results suggest that the performance of these polymers correlates to their physical characteristics. These characteristics were significantly influenced by changes in the experimental polymerisation parameters, and the complexity of the component mixture. A series of trends were observed as each parameter was altered, suggesting that the performance of a generated polymer could be possible to predict. As expected, component selection is shown to be a major factor in the success of an imprint using this method, but this also has a significant effect on the quality of resultant polymers suggesting that only certain types of MIPs can be made using microwave irradiation. This work also indicates that the controlled polymerisation conditions offered by microwave reactors could open a promising future in the development of MIPs with more predictable analyte recognition performance, assuming material selection lends itself to this type of initiation.
DMU School of Pharmacy undergraduate project scheme for financial support.
The full-text of this article will be released for public view at the end of the publisher embargo on 13 Aug 2021.

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Bompart, Marc. "Molecularly imprinted polymers and nano-composites by free radical and controlled/living radical polymerization : applications in optical sensors." Compiègne, 2010. http://www.theses.fr/2010COMP1870.

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Cette thèse est organisée en trois chapitres basés sur trois publications et deux manuscrits en cours de soumission. Les polymères à empreintes moléculaires (MIP) sont des récepteurs produits à façon qui sont obtenues par polymérisation en présence de molécules modèles. Le premier papier décrit l'utilisation de la spectroscopie Raman pour la détection et la quantification de molécules modèles au sein d'une particule unique de polymères a empreintes moléculaires de taille micrométrique. Les particules de polymères ont eté imprimées avec comme molécules modèles S-propranolol. Des particules de taille nanométrique et micrométrique ont été respectivement utilisées pour une analyse en masse et sur particule unique. La quantification de molécules cibles est possible sur particule unique et une limite de détection de 1µM a été obtenue sur l’analyse en masse. Le second papier décrit un capteur chimique de taille nanométrique composé d’une particule en core-shell composite. Cette particule comprend un cœur polymérique, une enveloppe inorganique composée de nanoparticules d’or pour l’exaltation du signal, recouvert d’une couche de polymères à empreintes moléculaires pour la reconnaissance. La méthode d’analyse utilisée est une exaltation su signal Raman appelé « surface enchanced Rama scattering ». Ces particules ont aussi été utilisées comme capteur avec la résonance plasmonique localisé comme méthode de transduction (papier n°3). Afin de résoudre certains problèmes associés aux polymères à empreintes moléculaires, tels que l’inhomogénéité en terme de morphologie et de distribution en site de reconnaissance, il a été suggéré d’utiliser des méthodes de polymérisations radicalaire contrôlées. Ces méthodes facilitent aussi leurs synthèses sous forme de nanomatériaux, nanocomposites et films minces. Le quatrième papier considère les récents avantages et inconvénients de ces nouvelles méthodes de polymérisation rapportés aux polymères à empreintes moléculaires. Le dernier papier décrit la première utilisation d’un récente méthode basée sur la polymérisation par transfert à l’iode (ITP), « reversible chain transfer catalyzed polymerization » (RTCP) adapté aux polymères à empreintes moléculaires. Nous décrivons un exemple de synthèse de MIP spécifiques pour la molécule propanolol par RTCP, produisant des polymères sous forme de « bulk » ou particules ayant la même capacité de reconnaissance que ceux synthétisés par polymérisation radicalaire (FRP). La RMN à l’état solide a révélée que la conversion en double liaison intramoléculaire était plus élevée dans le cas de polymères synthétisés par RTCP que par FRP, en particulier à haute concentration en amorceur
This thesis is organized in three chapters and is based on three published papers, and two manuscripts about to be submitted. Molecularly imprinted polymers (MIPs) are tailor-made synthetic receptors that are obtained by polymerization in the presence of a molecular template. The first paper describes the use of Raman spectroscopy to detect and quantify the presence of the imprinting template in single molecularly imprinted polymer microspheres. The polymers were imprinted with the Beta-blocking drugs propranolol and atenolol, and precipitation polymerization was used to obtain spherical particles. The nanoparticles were used for bulk detection whereas with micrometer-sized particles, quantitative measurements on single particles were possible. Relatively low detection limits down to 1µM have been reached for the detection of S-propranolol through bulk measurements on MIP nanoparticles. The second paper describes chemical nanosensors with a submicron core-shell composite design, based on a polymer core, a molecularly imprinted polymer (MIP) shell for selective analyte recognition, and an interlayer of gold nanoparticles for signal amplification. SERS measurements on single nanosensors yielded a detection limit of 10-7 M for the Beta-blocker propranolol, several orders of magnitude lower than on plain MIP spheres. These particles were also used as sensor materials with localized surface plasmon resonance measurements as the transduction method (Paper III), for the determination of the Beta-blocking drug propranolol. The sensors were used in suspension and were measured using a standard UV-Vis spectrophotometer. In order to solve general problems associated with MIPs, in particular their heterogeneity in terms of inner morphology and distribution of binding site affinities, it has been suggested to use modern methods of controlled/living radical polymerization for their synthesis. This also facilitates their generation in the form of nanomaterials, nanocomposites, and thin films, a strong recent trend in the field. The fourth paper reviews recent advances in the molecular imprinting area, with special emphasis on the use of controlled polymerization methods, their benefits, and current limitations. In the last paper, we have for the first time used a recently developed CRP method based on iodide mediated polymerization, reversible chain transfer catalyzed polymerization (RTCP), for the synthesis of MIPs. We show on the example of MIPs specific for the Beta-blocking drug propranolol that RTCP is compatible with MIP synthesis, both for the synthesis of bulk polymers and nanospheres, and that it yields polymers with the same binding capacity as the standard FRP method used for comparison. Solid-state NMR measurements revealed that the conversion of pendant vinyl groups was higher with RTCP than with polymers synthesized by FRP, in particular at higher initiator concentrations

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Marchyk, Nataliya. "Molecularly imprinted polymers as synthetic receptors for glucuronates, and their use for biochemical sensing." Compiègne, 2012. http://www.theses.fr/2012COMP2053.

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La reconnaissance moléculaire est un processus fondamental dans les systèmes biologiques. La création des récepteurs synthétiques imitant les processus biologiques est d'une grande importance dans l'application pratique en raison de leur plus grande stabilité aux milieu très rigoureux, long-durée de conservation et la flexibilité d'application par rapport à leurs homologues naturels. Polymères à empreintes moléculaires (MIPs) bien remplissent ces conditions. Les MIPs sont faits sur mesure récepteurs synthétiques qui sont capables de reconnaître spécifiquement une molécule cible. Leur synthèse est basée sur la présence d'une molécule cible qui dirige l'auto-assemblage autour des monomères fonctionnels. Les monomères copolymérisent dans un excès d'agent de réticulation. Par la suite, l’extraction d’une molécule cible libère des sites à trois dimensions dans la matière qui sont complémentaires dans la taille, la forme et la position des groupements fonctionnels de la cible. En raison de la complexité de la composition et des facteurs d’influence divers, la conception rationnelle devrait être utilisée afin d'améliorer la performance des systèmes à empreintes moléculaires. Les nanoparticules du type noyau/coquille proposent une possibilité unique d'incorporer des agents avec des propriétés optiques ou magnétiques dans le noyau, offrant des possibilités plus larges pour l'application des MIPs, par exemple dans l’imagerie biologique et de surveillance. Le travail de la thèse est axé sur le développement de MIPs pour la reconnaissance spécifique de glucuronates en milieu aqueux avec des perspectives d'application dans les systèmes biologiques. La conception rationnelle compris la modélisation moléculaire, l'analyse spectroscopique et la conception des expériences. La modélisation moléculaire a simulé des interactions intermoléculaires et a permis de découvrir les combinaisons d’analyse-monomère le plus prometteurs et qui pourraient être vérifiées in situ par spectroscopie. La conception des expériences avec l’optimisation multi-objectifs a permis de trouver la composition de MIP avec la meilleure performance pour le glucuronate ainsi que de comprendre les effets des facteurs d’influence, les concentrations des composés en particulier, sur la performance de MIPs. Transfert d'énergie par résonance de type Förster a été utilisée pour évaluer la reconnaissance de l'analyse cible par MIP. Dans la perspective de l'application dans les systèmes biologiques, l’approche nouvel de la synthèse des nanoparticules du type noyau/coquille a été proposé. Le principe est basé sur une synthèse en un seul récipient par polymérisation en émulsion classique des graines à iniferter qui servent de noyaux pour les particules finales. Les particules de conversion ascendante (UCPs) possèdent des propriétés optiques uniques pour absorber la lumière à longueur d'onde plus élevée et l'émettre à longueur d'onde plus courte. Cela les rend très prometteuse dans l’imagerie biologique, car l'autofluorescence des échantillons biologiques peuvent être considérablement diminuée. La stratégie a été proposée de synthétiser des nanoparticules composites du type noyau/coquille où des UCPs ont été utilisées comme source de la lumière locale seconde pour lancer la polymérisation de la surface des particules
Molecular recognition is a fundamental process in biological systems. The creation of synthetic receptors mimicking the biological processes is of high importance in practical application due to their higher stability to harsh environments, long on-shelf life and application flexibility comparing to natural counterparts. Molecularly imprinted polymers (MIP) readily meet these conditions. MIPs are tailor-made synthetic receptors that are able to specifically recognize a certain target molecule. Their synthesis is based on the presence of a molecular template that directs the self-assembly of functional monomers around. In an excess of cross-linking agent the monomers copolymerize, and subsequent removal of the template molecule generates three-dimensional binding sites in the material that are complementary to the template in size, shape and position of the functional groups. Due to complexity of composition and various influencing factors, the rational design should be employed in order to improve the performance of MIP systems. Core-shell nanoparticles provide a unique possibility to incorporate agents with optical or magnetic properties into the core, providing broader possibilities for MIPs application, such as in bioimaging and monitoring. The work of the thesis is focused on development of MIPs for the specific recognition of glucuronates in aqueous environment with outlook for applicability in biological systems. The rational design framework included molecular modelling, spectroscopic analysis and the design of experiments. Molecular modelling simulated intermolecular interactions and allowed to discover the most promising analyte-monomer combinations which could be verified in situ via spectroscopic (NMR) method. The design of experiments with multi-objective optimization allowed finding the composition of MIP with the best performance to glucuronate as well as to understand the effects of influencing factors, compounds concentrations in particular, onto the MIP performance. Förster resonance energy transfer (FRET) was applied in order to evaluate the recognition event of the target analyte in the MIP system. Bearing in mind the application in biological systems, a new approach for the synthesis of core-shell nanoparticles was proposed. The principle is based on one-pot synthesis by conventional emulsion polymerization of iniferter seeds which serve as cores for final particles. The up-converting particles (UCPs) possess unique optical properties to absorb the light at higher wavelength and emit it at lower wavelength. That makes them very promising in bioimaging, since the autofluorescence of biological samples can be decreased significantly. A novel strategy was proposed to synthesize composite core-shell nanoparticles where UCPs were employed as the second local light source to initiate the polymerization from the particles’ surface

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Latzo, Patricia M. "Evaluation of a moleculary imprinted polymer as a chiral stationary phase for the enantionmeric separation for D and L dansylphenylalanine using a capillary liquid chromatographic technique." Morgantown, W. Va. : [West Virginia University Libraries], 2000. http://etd.wvu.edu/templates/showETD.cfm?recnum=1660.

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Thesis (M.S.)--West Virginia University, 2000.
Title from document title page. Document formatted into pages; contains viii, 46 p. : ill. Includes abstract. Includes bibliographical references (p. 45-46).

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Panagiotopoulou, Maria. "Organic-inorganic composite materials for specific recognition and optical detection of environmental, food and biomedical analytes." Thesis, Compiègne, 2016. http://www.theses.fr/2016COMP2315/document.

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Cette thèse décrit l'état de l'art des sondes et nanoparticules fluorescents traditionnels utilisés en imagerie de fluorescence ainsi que le développement de nouveaux nanomatériaux à base de polymère à empreinte moléculaire, aussi dénommé ‘anticorps plastique’, pour le ciblage et la bioimagerie. En biologie et en médecine, il y a un besoin constant de diagnostiquer diverses maladies pour leur éventuel traitement et prévention. Une distribution anormale et un taux élévé de glycosylation (e.g. acides hyaluronique et sialique) à la surface ou dans les cellules sont indicateurs d’une infection ou d’un cancer. Généralement, l’imagerie par fluorescence permet de visualiser, localiser et quantifier les biomarqueurs de pathologie mais à l’heure actuelle, il n’existe pas d’outil analytique fiable pour cibler spécifiquement les molécules de glycosylation car les anticorps et les lectines vendus dans le commerce ont une faible affinité et sélectivité vis-à-vis de ces cibles. Dans ce contexte, les polymères à empreintes moléculaires (MIPs) pourraient apporter une solution. Les MIPs sont des récepteurs synthétiques possédant des affinités et sélectivités comparables à ceux des anticorps, mais exhibant une stabilité physique, thermique et chimique bien plus accrue. De plus, leur fabrication est peu coûteuse et ne nécessite pas de tuer des animaux comme pour l’obtention des anticorps biologiques. Dans cette thèse, nous avons optimisé et synthétisé des MIPs biocompatibles pour leur utilisation en bioimagerie afin de détecter et quantifier l’acide hyaluronique et l’acide sialique sur les cellules et les tissus de peau humaine. L’acide glucuronique, une composante de l’acide hyaluronique et l’acide N-acétylneuraminique, l’acide sialique le plus commun, ont été utilisés comme molécules ‘patron’, générant des MIPs très sélectifs envers leur cible en milieu aqueux. Deux types de nanoparticules de MIPs fluorescents ont été synthétisés: (1) en incorporant un colorant rhodamine polymérisable dans la solution de pré-polymérisation et (2) en encapsulant des boîtes quantiques InP/ZnS générant ainsi des MIPs de type cœur-coquille. Pour cela, nous avons adopté une stratégie innovante qui consiste à synthétiser les coquilles de MIPs directement autour des boîtes quantiques en utilisant l’énergie de l’onde fluorescente émise par l’excitation des points quantiques, pour initier la polymérisation. Un protocole d'immunocoloration standard a ensuite été optimisé afin d’imager des kératinocytes humains fixés et vivants ainsi que des tissus de peau, par microscopie à épifluorescence et confocale. Les résultats étaient similaires à ceux obtenus par la méthode de référence utilisant une protéine biotinylée reconnaissant l'acide hyaluronique. L'imagerie multiplex en combinant deux MIPs couplés à deux couleurs de boîtes quantiques et l’imagerie des cellules cancéreuses ont également été démontrées. Bien que les MIPs n’étaient pas cytotoxiques aux concentrations utilisées pour la bioimagerie, la toxicité des différentes composantes du MIP pourrait être un frein à leur utilisation dans le domaine biomédical. Afin de rendre ces MIPs plus ‘inoffensifs’, nous avons supprimé l’amorceur de polymérisation, une molécule considérée comme toxique. Les MIPs ont été synthétisés en employant des monomères qui s’auto-initient sous l’effet de l’UV ou de la chaleur. La spécificité et la sélectivité des MIPs obtenus étaient similaires à ceux préparés avec des amorceurs. En conclusion, cette thèse décrit la première utilisation des MIPs comme anticorps synthétique pour la bioimagerie de fluorescence. Ce travail ouvre la voie à de nouvelles applications en détection, diagnostique et thérapie par des MIPs
This thesis describes the state of the art in nanomaterials-based targeted bioimaging and introduces molecularly imprinted polymers, also termed ‘plastic antibodies’ as novel biorecognition agents for labeling and imaging of cells and tissues. In fundamental biology and medical diagnostics, there is a constant need to localize and quantify specific molecular targets. Abnormal glycosylation levels or distributions of hyaluronan or sialic acids on cells are indicators of infection or malignancy. In general, bioimaging with fluorescent probes enables the localization and qualitative or quantitative determination of these pathological biomarkers. However, no reliable tools for the recognition of glycosylation sites on proteins exist, because the commercially available antibodies or lectins have poor affinity and selectivity for these targets. In this context, tailor-made molecularly imprinted polymers (MIPs) are promising synthetic receptor materials since they present a series of advantages over their natural counterparts such as the ease and low cost of preparation and their physical and chemical stability. Thus, MIPs could provide a robust and specific imaging tool for revealing the location/distribution, time of appearance and structure of glycosylation sites on/in cells, which would lead to a better insight of the tremendously diverse biological processes in which these molecules are involved. Herein, we describe the synthesis of water-compatible MIPs for the molecular imaging of hyaluronan and sialylation sites on cells and tissues. Since molecular imprinting of entire biomacromolecules like oligosaccharides is challenging, we opted for what is commonly called the ‘epitope approach’, which was inspired by nature. The monosaccharides, glucuronic acid and N-acetylneuraminic acid were imprinted, and the resulting MIPs were able to bind these molecules when present and accessible on the terminal unit of hyaluronan and sialylation sites. Fluorescent MIPs were synthesized as rhodamine-labeled nanoparticles and as MIP-coated InP/ZnS core-shell quantum dot (QD) particles. For the coating of the QDs, a novel versatile solubilization and functionalization strategy was proposed, which consists of creating polymer shells directly on QDs by photopolymerization using the particles as individual internal light sources. A standard immunostaining protocol was then successfully adapted for the application of the fluorescently labeled MIPs to image fixed and living human keratinocytes and skin tissues, by epifluorescence and confocal fluorescence microscopy. The results were comparable to those obtained with a reference method where staining was done with a biotinylated hyaluronic acid binding protein. Multiplexed and cancer cell imaging were also performed, demonstrating the potential of molecularly imprinted polymers as a versatile biolabeling and bioimaging tool. Although the MIPs were not cytotoxic at the concentrations used for bioimaging, in order to render them generally applicable in biomedicine, where toxicity of the polymerization precursors is a matter of concern, we suppressed the initiator, a toxic chemical. Initiator-free MIPs were thus synthesized by using monomers that can self-initiate under UV irradiation or heat. The specificity and selectivity of the obtained MIPs were as good as the ones prepared with initiators. In conclusion, we have demonstrated for the first time the great potential of MIPs as synthetic antibody mimics for bioimaging. The possibility to associate other functionalities such as QDs and additionally attach drugs to the same material appears rather straightforward due to the synthetic polymeric nature of MIPs, which paves the way to new potential applications in theranostics

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Plácido, Manuel Diogo Gonçalves. "Estudo da biocompatibilidade de materiais híbridos para aplicações biomédicas, adsorção de glucose." Master's thesis, Universidade de Évora, 2018. http://hdl.handle.net/10174/24851.

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A diabetes apresenta rápida evolução epidemiológica. Inúmeros estudos confirmam o aumento da prevalência e incidência da diabetes no mundo, sendo considerada a epidemia do século XXI e uma das principais causas de morbidade e mortalidade a nível mundial. O presente trabalho surge neste âmbito de pesquisa cujo objetivo foi testar o perfil de citotoxicidade de novos materiais híbridos - produzidos através de metodologias de impressão molecular - avaliado por culturas de células de insulinoma de rato (BRIN-BD11). Os materiais foram desenvolvidos a partir de materiais de carbono porosos e estruturas poliméricas especificas de modo a reconhecer e captar seletivamente glucose. Os resultados obtidos neste trabalho demonstraram que todos os materiais estudados têm a capacidade de adsorver glucose, em especial o material compósito F200 0/+1 com o maior valor de adsorção máximo (126,55 mg Glucose/g MIP), e que os materiais compósitos parecem não afetar a viabilidade celular; Abstract: “Study of the biocompatibility of hybrid materials for biomedical applications, glucose adsorption” Diabetes presents a rapid epidemiological evolution. Numerous studies confirm the increase of prevalence and incidence of diabetes in the world, being considered the 21st century epidemic and one of the main causes of morbidity and mortality worldwide. The present work appears in this scope of research whose objective was to test the cytotoxicity profile of new hybrid materials - produced through molecular imprinting methodologies - evaluated by cultures of rat insulinoma cells (BRIN-BD11). The hybrid materials were developed from hydrothermal, porous carbon materials and specific polymeric structures to recognize and selectively capture glucose. The results obtained in this work demonstrated that all the materials studied have the ability to adsorb glucose, especially the F200 0/+1 composite with the highest maximum adsorption value (126.55 mg Glucose/g MIP), and that the materials do not appear to affect cell viability.

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Marie, Héléne. "Elaboration of a new sensor based on molecularly imprinted polymers for the detection of molecules in physiological fluids." Phd thesis, Université de Technologie de Compiègne, 2013. http://tel.archives-ouvertes.fr/tel-00977390.

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This thesis aimed at elaborating an optical sensor to detect molecules in a biological fluid. Two steroids and a xenobiotic were identified as biomarkers released in some body fluids: cyproterone acetate, cortisol and 2,4-dichlorophenoxyacetic acid respectively. On one hand, detection was performed by Molecularly Imprinted Polymers (MIPs). These tailor-made synthetic receptors display numerous qualities that foster their integration in sensors. MIPs were therefore developed against the targeted analytes. Formulation optimization was led thanks to experimental designs. On the other hand, optical transduction was made possible thanks to the structuring of a polymer into a photonic crystal. Opals were manufactured with a new process suitable for large scales and were used to mold MIPs in inverse opals. Thus, submicron structures of the polymer are responsible for the color of the sensor. A change of color is triggered by the recognition of the analyte by the polymer (upon swelling). Polymers studied displayed sufficient swelling observed by spectrophotometry. Finally, the work of this thesis consisted in elaborating polymer formulations and their integration in a sensor so as to detect an analyte with direct, rapid and unobtrusive means.

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Peçanha, Bruna Rachel de Britto. "Síntese de polímeros de impressão molecular e sua aplicação na técnica de extração em fase sólida." Niterói, 2017. https://app.uff.br/riuff/handle/1/3102.

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Polímeros de impressão molecular (MIPs) foram sintetizados e aplicados como adsorventes na técnica de extração em fase sólida (EFS). O método de polimerização por precipitação foi utilizado para a síntese dos polímeros, devido à simplicidade de preparo, altos rendimentos e obtenção de partículas mais uniformes, devido a não trituração do polímero. O MIP foi sintetizado com ácido metacrílico (MAA) como monômero funcional, trimetacrilato de trimetilolpropano (TRIM) e dimetacrilato de etilenoglicol (EDMA) como agentes de reticulação e o cloridrato de amilorida (AMI) foi escolhido como molécula-molde. Diferentes proporções de MAA, TRIM, EDMA, volume e tipo de solvente foram utilizadas para ajuste das condições ideais de síntese. Os MIP foram avaliados quanto à capacidade de adsorção comparando-se a polímeros sintetizados na ausência da molécula-molde (NIP, polímeros não impressos). O solvente de elevada polaridade empregado na síntese (THF:MeOH:H2O) permitiu o emprego da técnica para moléculas polares como AMI. O controle no volume de solvente permitiu a obtenção de partículas maiores, de modo que a EFS foi realizada em condições usuais, o que confere um potencial para aplicação dessa técnica de polimerização na preparação de adsorventes para EFS. O polímero que apresentou maior capacidade adsortiva no ensaio realizado em tampão citrato-acetato pH 6,5 foi o MIP/NIP 12 (AMI:MAA:TRIM 1:8:10), com uma taxa média de adsorção de 83 e 88% para NIP e MIP, respectivamente. A adsorção foi elevada devido a interação iônica entre MAA e AMI promovida pelo controle de pH, porém foi não específica. O polímero MIP/NIP 12 foi aplicado como adsorvente na EFS, onde a recuperação de AMI foi avaliada nos resíduos de carregamento e eluição com solventes. O carregamento com tampão citrato-acetato pH 6,5 foi o ideal, favorecendo a interação iônica do polímero com o analito. A eluição total de AMI do cartucho somente ocorre após lavagem com o solvente na presença de ácido, que protona os grupos carboxila do polímero, rompendo assim a interação iônica com o analito
Molecularly imprinted polymers (MIPs) were synthesized and applied as adsorbents in solid-phase extraction technique (SPE). The polymers have been synthesized by precipitation polymerization method because of its simplicity, high yields and good control of final size and shape of particles. MIP was synthesized using methacrylic acid (MAA) as functional monomer, trimethylolpropane trimethacrylate (TRIM) and ethyleneglycol dimethacrylate (EDMA) as cross-linker and amiloride hydrochloride (AMI) was chosen as template. Different ratios of MAA, TRIM and EDMA, volume and type of solvent were used to adjust the optimal synthesis conditions. The MIP were tested for adsorption capacity compared to the polymers synthesized in the absence of template molecule (NIP, non-imprinted polymers). The polar solvent mixture used (THF:MeOH:H2O) allowed the synthesis of MIP of polar molecules as AMI. The solvent volume control afforded the larger particles so the SPE was performed in the usual conditions, giving a potential application for this polymerization technique in the preparation of adsorbents for SPE. The polymers with higher adsorption capacity at the test performed in citrateacetate buffer pH 6,5 was MIP/NIP 12 (AMI:MAA:TRIM 1:8:10) with adsorption rate of 83 and 88% for NIP and MIP, respectively. The recognition of MIP was due to ionic interaction between MAA and AMI promoted by pH control, but was not specific. The polymer MIP/NIP 12 was used as a solid-phase extraction sorbent and the recoveries of AMI was evaluated using different loading and elution conditions. The loading with buffer citrate-acetate pH 6,5 was optimal, due to ionic interaction of the polymer with the analyte. Total elution of AMI bound to the polymers only occurs after washing with a acid-containing solvent, because of protonation of the carboxyl groups of the polymer and disrupting the ionic interaction with the analyte

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Saadaoui, Asma. "Développement de nouveaux monomères biosourcés à base d’Isosorbide et applications à la synthèse de matériaux à applications spécifiques." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSE1036.

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L'isosorbide et ses dérivés sont des diols chiraux issus de l'amidon de maïs. L'utilisation de ce dernier en tant que monomère pour l'élaboration de polymères s'est révélée efficace, ces derniers égalant les propriétés des polymères conventionnels. Dans le cadre de cette thèse, ces diols sont employés pour synthétiser de nouvelles plateformes des monomères biosourcés AA et AB à partir des 1,4 :3,6- dianhydrohexitols. La synthèse d'intermédiaires à base de dinitriles ou de mononitriles et leurs dérivés à partir des trois isomères ainsi que les résultats d'essais de polymérisation de l'un de ces monomères prometteurs ont été décrits. Le polymère obtenu a révélé semi-cristallin grâce à l'agencement stéréorégulier des monomères AB. Ce travail est aussi le premier à décrire l'utilisation des réticulants chiraux à base de 1,4 :3,6-dianhydrohexitols participant à la formation du réseau tridimensionnel pour l'élaboration de polymères à empreintes (MIP) biosourcés pour la détéction de la Méthyltestostérone (MT). Les polymères synthétisés par polymérisation par précipitation ont été caractérisés. Les propriétés de rétention ont été évaluées en mode batch par HPLC-MS/MS. Ces MIPs présentent de bonnes propriétés d'adsorption vis-à-vis la MT avec des facteurs d'empreinte supérieurs à 1 montrant l'efficacité de l'impression. Ces matériaux présentent une bonne capacité d'adsorption comparée à la littérature. Les polymères non imprimés (NIP) ont même montré des capacités d'adsorption supérieure aux MIP classiques. La capacité d'adsorption la plus élevée a été observée pour cMIP-Is à base d'isosorbide, pour les concentrations importantes (500 mg L-1). Les données expérimentales ont été étudiées selon les modèles d'adsorption de Langmuir et Freundlich pour interpréter les phénomènes d'adsorption. Ces cMIP développés ont été adaptés pour l'extraction de la méthyltestotérone sur phase solide (SPE). Une procédure d'extraction a été développée en menant au travers d'une optimisation complète finalisée par une application aux eaux usées
The isosorbide and its derivatives are chiral diols obtained from cornstarch. The use of the latter as a monomer for the development of polymers has proved to be effective. The diols match the properties of conventional polymers. As part of this thesis, the diols are used to synthesize new platforms of bio based AA and AB from the 1,4: 3,6 - dianhydrohexitols monomers. The synthesis of intermediaries based on dinitriles or mononitrilies and their derivaties starting from the three isomers as well as the test results from one of these promising monomers polymerization which have been described. The resulting polymer revealed semi-cristallin through stereoregulier AB monomers layout. This work is also the first to describe the use of the reticulants chiral at base of 1.4: 3, 6-dianhydrohexitols participating in the formation of three-dimensional network for the development of polymers to footprints (MIP) Excelsior for detection of Methyltestosterone (MT). The polymers synthesized by polymerization have been characterized by precipitation. The properties of retention were evaluated in batch mode by HPLC-MS/MS. These MIPs present good properties of adsorption towards the MT with factors of footprint greater than 1 showing the effectiveness of printing. These materials have a good ability of adsorption compared to literature. Unprinted polymers (PIN) have shown even greater adsorption capacity than the conventional MIP. The high adsorption capacity was observed in cMIP-Is based on isosorbide for the concentrations (500 mg L-1). The experimental data have been studied according to Langmuir and Freundlich adsorption models to interpret the phenomena of adsorption these developed cMIP have been adapted for the methyltestoterone on the phase of extraction (SPE) solid. An extraction procedure has been developed leading through a full optimization finalized by an application in wastewater

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Franco, Jefferson Honorio [UNESP]. "Biotransformação de corantes dispersos do tipo azo pela ação de enzimas redutoras e oxidação fotoeletrocatalítica após pré-concentração por MIP." Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/144994.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Corantes sintéticos do tipo azo têm sido um assunto de grande preocupação ambiental devido ao potencial genotóxico e mutagênico dos produtos de biotransformação. Deste modo, nos últimos anos a consequência da ingestão destes corantes presentes na agua potável servida à população é discutida por diversos autores. Este estudo avalia a ação de microssomas de fígado de rato, enzimas redutoras produzidas pela bactéria Escherichia coli (E. coli) e nitroredutase imobilizada na biotransformação de três corantes dispersos que possuem grupos azo, Disperse Red 73 (DR 73), Disperse Red 78 (DR 78) e Disperse Red 167 (DR 167). A técnica de Espectrofotometria de absorção molecular na região do Uv- visível, Cromatografia Líquida de Alta Eficiência com detector de arranjo de diodos (CLAE-DAD) e Cromatografia líquida acoplada à espectrometria de massas (LC-MS/MS) foram técnicas usadas para identificar os principais produtos gerados após os processos de degradação dos corantes. Polímeros de impressão molecular magnéticos (MMIPs) foram investigados usando reações de polimerização por precipitação para pré-concentração do corante DR 73, juntamente com a degradação por fotoeletrocatálise e subsequente análise dos produtos por LC-MS/MS. Os estudos in vitro do metabolismo de biotransformação dos corantes têxteis com microssoma de fígado de rato mostraram que as reações ocorreram preferencialmente no grupo azo e nitro dos corantes, indicando a redução destes grupos pelas enzimas do citocromo P-450. Foram obtidos dois produtos de degradação para cada corante após reação com a bactéria E. coli; o corante DR 73 originou os produtos 3-((4-aminofenil)(etil)amino)propanitrila e 4-nitroanilina, os produtos 3-((4-aminofenil)(etil)amino)propanitrila e 2-cloro-4-nitroanilina foram obtidos após reação com o corante DR78 e o DR 167 originou dimetil 3,3`-((3-acetamido-4aminofenil)azanediyl)dipropanoato e 2-cloro-4-nitroanilina, indicando a clivagem do grupo azo, possivelmente, pela enzima azoredutase, produzida pela bacteria. A enzima nitroredutase, imobilizada em partículas magnéticas modificadas com tosil, mostrou que a redução dos corantes ocorreu preferencialmente no grupo nitro, enquanto que a enzima livre no meio reacional resultou em mais de um produto de biotransformação para cada corante, atuando em mais de um sítio da molécula, comprovando a eficácia da imobilização enzimática para estudos de biotransformação e formação de produtos majoritários. A mutagenicidade dos corantes foi avaliado pelo ensaio de Salmonella/microssoma realizado nas estirpes TA 98 e TA 100, com e sem S9. De acordo com este ensaio, DR 73 foi o mais mutagênico. O MMIP para o corante DR 73 apresentou excelentes valores de religação (16 mg g−1 e 6 mg g−1, para MMIP e MNIP, respectivamente) indicando que o polímero molecularmente impresso formou cavidades específicas para retenção do corante. Através dos resultados obtidos por LCMS/MS, observou-se 100% de degradação do corante em apenas 60 min de tratamento via fotoeletrocatálise para soluções mais diluidas do mesmo, comprovando a eficiência da técnica na degradação de poluentes. Sendo assim, estes resultados sugerem que o MMIP mostrou uma excelente especificidade e seletividade para o corante DR 73 e uma técnica promissora na captação de corantes mutagênicos de águas superficiais, com grande potencial de aplicação e exploração na pré-concentração antes do tratamento. Além disso, a redução destes corantes por sistemas biológicos representa uma grande preocupação ambiental devido ao aumento da genotoxicidade para os seres vivos, em especial a seres humanos, produzindo compostos nocivos, tais como aminas condenadas pela Agência Internacional de Pesquisa sobre o Câncer.
Synthetic azo dyes have been a matter of great concern due to the genotoxic and mutagenic potential of the products originating from azo dye biotransformation. Thus, in recent years the result of the intake of these dyes present in drinking water supplied to a population is discussed by several authors. This work evaluates the action of rat liver microsomes, reducing enzymes produced by the Escherichia coli (E. coli) and nitroreductase immobilized on biotransformation of three disperse dyes bearing azo groups, namely Disperse Red 73 (DR 73), Disperse Red 78 (DR 78), and Disperse Red 167 (DR 167). UV-Vis spectrophotometry, high-performance liquid chromatography with diode array detector (HPLC-DAD), and liquid chromatography coupled to mass spectrometry (LC-MS/MS) were techniques used to identify the main products generated after the process degradation of dyes. Magnetic molecularly imprinted polymers (MMIPs) were investigated using precipitation polymerization reactions for preconcentration of the dye DR 73, together with the photoelectrocatalysis degradation and subsequent analysis of the products by LC-MS/MS. In vitro studies of biotransformation metabolism of textile dyes with rat liver microsome showed that the reactions occur preferentially in the group of azo and nitro dyes, indicating the reduction of these groups by enzymes of the cytochrome P-450. There were obtained two degradation products for each dye after reaction with E. coli; the dye DR 73 gave the product 3 - ((4-aminophenyl) (ethyl) amino) propanitrila and 4-nitroaniline, the product 3 - ((4-aminophenyl) (ethyl) amino) propanitrila and 2-chloro-4-nitroaniline were obtained after reaction with the dye DR78 and DR 167 gave 3,3`-dimethyl-((3-acetamido-4-aminophenyl) azanediyl) dipropanoato and 2chloro-4-nitroaniline; indicating cleavage of the azo group, possibly by azoredutase enzyme produced by bacteria. The nitroreductase enzyme immobilized on modified magnetic particles Tosyl showed that the reduction of dyes occurred preferentially in the nitro group, while the free enzyme in the reaction medium resulted in more than a product of biotransformation for each dye, acting in more than one site of the molecule, proving the efficacy of enzyme immobilization for biotransformation studies and formation of major products. The mutagenicity of the dyes was evaluated by the Salmonella/microsome assay performed on strains TA 98 and TA 100, with and without S9. According to this assay, DR 73 was the most mutagenic. The MMIP to the dye DR 73 showed excellent rebinding values (16 mg g−1 and 6 mg g−1, for MMIP and MNIP, respectively) indicating that the molecularly imprinted polymer formed cavities for specific dye retention. Through the results obtained by LC-MS/MS, it was observed 100% dye degradation in 60 min treatment for more dilute solutions thereof, proving the efficiency of technique in pollutant degradation. Thus, these results suggest that MMIP showed excellent specificity and selectivity for the dye DR 73 and a promising technique in capturing mutagenic dyes of surface water, with great potential for application and operation in the pre-concentration before treatment. Moreover, the reduction of these dyes by biological systems is a major environmental concern due to increased of genotoxicity for living beings, especially humans, producing harmful compounds, such as condemned amines by the International Agency for Research on Cancer.

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40

Bokeloh, Frank. "Development of organic microelectromechanical chemosensors based on fiber optics." Thesis, Compiègne, 2017. http://www.theses.fr/2017COMP2381.

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Un (bio)capteur classique est principalement composé de deux éléments essentiels : une couche réceptrice sensible à l’analyte à laquelle on s’intéresse et un transducteur qui permet de convertir une stimulation chimique / biologique en un signal physique mesurable. Dans le cas idéal, un capteur ne doit pas nécessiter de marquage de la cible, doit posséder de très grandes sensibilité et sélectivité envers elle, ne requiert qu’une faible quantité de cette dernière et doit présenter un temps de réponse très court. Au vu de ces critères, les microsystèmes électromécaniques (MEMS) sont des candidats très prometteurs dans le développement de capteurs. Les polymères fonctionnels, tels que les polymères à empreinte moléculaire (MIPs), sont une approche très intéressante dans l’utilisation des MEMS car ils peuvent être intégrés dans des technologies existantes de MEMS à base de silicium ou complètement remplacer ces technologies. Le but de cette thèse porte sur le développement d’un capteur MEMS composé de polymères (fonctionnels). Un chapitre initial (chapitre 2) introduit des nouveaux systèmes de fabrication de polymères fonctionnels. Des biopuces composées de MIPs imprimés par jet d’encre sont présentées ainsi qu’une technique basée sur la polymérisation radicale contrôlée qui permet le dépôt d’un fin enrobage de MIPs sur des microstructures. La deuxième partie de ce chapitre présente la fabrication de polymères à empreinte moléculaire par stéréolithographie deux-photons, qui peut être vue comme une extension de l’impression 3D. Afin d’illustrer cette technologie de prototypage rapide, deux capteurs composés de MIPs sont présentés : un capteur à grille de diffraction et un capteur en microlevier. Les deux principaux chapitres de ce manuscrit (chapitre 3 et 4) se focalisent sur le développement d’un nouveau concept de fabrication pour les capteurs MEMS. Ce concept est basé sur la polymérisation d’une poutre à fort ratio de forme à l’extrémité d’une fibre optique de télécommunication. Cette poutre a été mise en vibration à sa résonnance et a ainsi pu être utilisée comme un capteur à base de levier. Le capteur en polymère a permis l’intégration de MIPs comme élément récepteur et la reconnaissance sélective de l’antibiotique enrofloxacine. De plus, un nouveau système de mesure intégré est présenté dans le chapitre 4. Ce système de mesure intègre la fibre optique en guidant un rayon laser à travers elle ainsi qu’à travers le levier qui y est attaché.Le rayon lumineux sortant est ensuite focalisé sur une photodiode sensible à la position du rayon lumineux, permettant ainsi la mesure du spectre de résonance de la poutre en polymère. Ce système de mesure est caractérisé et ses performances sont présentées au travers de la détection de masse du levier en polymère et de mesures faites en milieu liquide
A classical (bio)sensor consists of two key components: A receptor layer that detects the analyte of interest and the transducer which converts the chemical / biological stimuli into a physical measurable signal. Ideally a sensor is label-free, highly sensitive and selective towards the target, requires low sample amount and shows a fast response time. Regarding these criteria microelectromechanical systems (MEMS) offer great potential for the sensor development. One interesting approach for this development are functional polymer materials, such as molecularly imprinted polymers (MIPs), that can be either integrated to existing MEMS based on silicon or completely replace the silicon technology. The emphasis of this thesis is focused on the development of a MEMS sensor based on (functional) polymers. In an initial chapter (chapter 2) new fabrication schemes for functional polymers are introduced. Inkjet-printed biochips based on MIPs are presented and a technique based on controlled radical polymerization is shown that allows the deposition of thin MIP shells on a microfabricated pattern. In the second part of this chapter the fabrication of molecularly imprinted polymers by two-photon stereolithography is shown which can be seen as an extension of 3dimensional printing. As possible application of this rapid prototyping technology two sensors based on MIPs are introduced a diffraction grating sensor and a microcantilever sensor. The two main chapters of this manuscript (chapter 3 and chapter 4) report the development of a new fabrication concept for MEMS sensors. It is based on the polymerization of a high aspect ratio beam on the extremity of an optical telecommunication fiber which was actuated at resonance and thus could be used as a cantilever sensor. The polymer sensor allowed the integration of MIPs as sensing element and the selective recognition of the antibiotic enrofloxacin. Furthermore, is a new, integrated read-out scheme presented in chapter 4. This read-out scheme integrates the optical fiber, by guiding a probe laser beam through it and attached cantilever beam. The output light beam is then focused on a position sensitive photodiode and thus enabled to monitor the resonance spectra of the polymer beam. The read-out scheme is characterized and its performance is shown by demonstrating the mass sensitivity of the polymeric cantilever beam and by measurements in liquid environments

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Tom, Lou Ann. "Development of a molecularly imprinted polymer (MIP) for the analysis of avermectin /." Diss., 2005. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3167083.

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Chen, Pei-Syuan, and 陳姵璇. "The development of molecularly imprinted polymer(MIP)-based cardiac troponinT sensing electrodes with corresponding clinical feasibility study." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/a9bn8f.

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碩士
國立交通大學
電子研究所
108
Cardiac troponinT(cTnT) is a highly sensitive cardiac biomarker to Acute myocardia linfarction(AMI) in clinical trial. In this study, we applied molecularly imprinted polymer(MIP) technology for the fabrication of cTnT sensing electrode.The MIP cTnT sensing electrode is first fabricated by electrochemical polymerization of o-phenylenediamine(o-PD) with cTnT on a gold layer , and then extracted the cTnT by the mixture of ethanol and NaOH solution to form the electrode. to discussion the effect of current to measurement of cTnT concentration. Experimental measurement shows there are no geometric effects including area and thickness on the measurement of cTnT concentration by the as-fabricated MIP electrode. For clinical validation, the MIP electrode has been applied for the detection of cTnT in the serum from the patients who are under the conditions of the usage of ECMO, AMI, before and after heart surgery, the process of hemodialysis, and the symptom of artery occlusive, respectively. Experimental results also show that the cTnT in these patients’ serum can be accurately measured from 0.01 ng/mL to 10 ng/mL usng the MIP sensing electrode in 15 mintues. The characteristics of simple structure, rapid measurement, and high accuracy and reusability have shown the potential of MIP cTnT sensing electrode for integrated sensor fabrication for clinical applications.

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43

Chakraborty, Twarita. "Molecularly Imprinted Polymers Based On Fluorescent And Template Binding Cross-Linker." Thesis, 2007. http://etd.iisc.ernet.in/handle/2005/2006.

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The synthesis of materials with molecular recognition properties has become a topic of great technological and scientific interest. Molecular imprinting is one of the most effective strategies in preparing highly selective synthetic receptors. The technique of molecular imprinting involves the copolymerization of functional and cross-linking monomers in the presence of a molecular template. Following polymerization and subsequent removal of the template, the molecularly imprinted polymer (MIP) retains a “molecular memory” of the template. During rebinding, the resultant polymer shows higher affinity and selectivity towards the molecular template when compared to other structural analogs. Ease of preparation and high thermal and chemical stability of this class of materials offers a broad range of potential applications. Promising areas of application include separation, chromatography, catalysis, sensors, antibody mimics, and drug delivery etc. The thesis entitled “Molecularly Imprinted Polymers based on Fluorescent and Template binding Cross-linker” deals with the design and synthesis of several molecularly imprinted polymers (MIPs) using different functional and cross-linking monomers, the main focus being use of preformed template-monomer complex, use of fluorescent cross-linker and development of functional group containing cross-linker. Chapter 1: An Introduction to Molecularly Imprinted Polymers. The first chapter provides an introduction to the field of molecularly imprinted polymers. It presents an overview of molecular imprinting process including a brief history of its discovery and its evolution to the present form. This chapter further elaborates on the principle of molecular imprinting with an emphasis on different parameters that directly affect their performance. It also provides a brief review of the applications of molecularly imprinted polymers. Chapter 2: Highly Cross-linked Metal Ion Imprinted Polymers. The second chapter deals with the synthesis of series of highly cross-linked metal-ion imprinted polymers. The process of metal ion-imprinting usually involves carrying out the polymerization and cross-linking directly in presence of the appropriate metal ion. In the present study, chemical-immobilization method was adopted which involves the use of preformed metal complexes with polymerizable group for the imprinting. Acrylate complexes of various metal-ions, such as Cu2+, Zn2+, Co2+, Ni2+, Pb2+ and Cr3+, were synthesized prior to polymerization. These pre-assembled complexes were then used to prepare MIPs, in the anticipation that this would lead to enhanced selectivity. Ethyleneglycol dimethacrylate (EGDMA) was used as the cross-linking monomer. As a control, the respective non-imprinted polymers (NIPs) were also made in absence of the template metal ion. Following polymerization, the template metal ion was extracted from the resultant metal ion-imprinted polymer. The selectivity of the metal ion-imprinted polymers was examined by a batch process using analytical tools, such as, Atomic Absorption Spectroscopy (AAS) and Inductively Coupled Plasma Spectroscopy (ICP). The spectroscopic studies revealed significant selectivity of all the MIPs towards the template metal ion. Among all six metal ion-imprinted polymers, Pb2+ and Cr3+ ion-imprinted polymer showed remarkable selectivity, followed by Cu2+ and Zn2+ ion-imprinted polymers. The Co2+ and Ni2+ ion-imprinted polymers exhibited comparatively poor selectivity. Representative plots depicting the selectivity exhibited by Pb2+ and Cr3+ ion-imprinted polymers are shown in Figure 1. These observations were rationalized based on the size and geometric preferences imposed by the imprinted site on the ion that binds to it. Figure 1. Selectivity study for (a) Pb2+ ion-imprinted polymer, (b) Cr3+ ion-imprinted polymer. Chapter 3. Molecularly Imprinted Fluorescent Chemosensor for Copper (II). Cu(II) is a source of important pollutant and therefore, the development of sensors that can detect Cu(II) selectively as well as remove Cu(II) from contaminated samples is an important objective. The use of molecular imprinting technique is an appealing approach in this regard. For this, a fluorophore containing cross-linker, namely 9,10-bis-(acryloyloxymethyl)anthracene (BAMA) was synthesized. This fluorescent cross-linker was used along with the standard cross-linker, EGDMA, for preparing Cu2+ ion-imprinted polymer. The complex of copper methacrylate (Cu-MAA) was prepared prior to polymerization used for the preparation of MIP. The resultant imprinted polymer exhibited quenching of the fluorescence in presence of Cu2+ ion, both in organic and aqueous medium. The efficiency of quenching of NIP (prepared in absence of Cu2+ ion) was significantly lower than that of MIP. A typical stack spectra showing the quenching process, along with a comparison of the quenching efficiency of MIP and NIP is shown in Figure 2. The imprinted polymers showed significant selectivity over other non-template metal ions, thereby reaffirming the importance of the imprinting process. The sensitivity of the fluorescence detection could be enhanced by increasing the level of the fluorophore incorporation. The increased sensitivity in detecting Cu2+ ion, demonstrated by the MIP suggests that a statistically random incorporation of the fluorophore into MIP matrices could be a useful approach for imparting a sensing element to MIPs. Figure 2. Fluorescence spectra of the (a) imprinted (MIP-1) and (b) non-imprinted (NIP-1) polymers in the presence of various concentration of Cu(OAc)2 in methanol. (c) Comparison of quenching efficiency of MIP-1 and NIP-1. Data were collected 3 h after addition of copper solution. I0 and I are the fluorescence intensities at 399 nm of the polymers in the absence presence of copper respectively. Two individual runs are presented in (c). Chapter 4. Molecularly Imprinted Turn-Off-On Sensor. This chapter describes the design and synthesis of molecularly imprinted fluorescent turn-off-on sensor utilizing the same fluorescent cross-linker, BAMA. Combining the process of fluorescence resonance energy transfer (FRET) with molecular imprinting technique, a novel turn-off-on sensor was developed. A molecularly imprinted polymer was prepared using a fluorescent template Coumarin-30 (C-30). C-30 was chosen as the template to ensure a significant overlap of the emission spectra of BAMA and the absorption spectra of C-30, thereby optimizing for FRET. Figure 3. Structures of relevant molecules. The C-30 imprinted polymer exhibited simultaneous quenching in fluorescence (turn-off) of BAMA and enhancement in fluorescence (turn-on) of C-30 (Figure 4). The imprinted polymer showed significantly better performance over the non-imprinted polymer (NIP). Figure 4. Fluorescence spectra of the (a) imprinted (MIP) and (b) non-imprinted (NIP) polymers with increasing concentration of the template Coumarine-30 in methanol. The UV-vis studies revealed that the more effective quenching is indeed due to the affinity for C-30 exhibited by the higher binding imprinted polymer. The imprinted polymer also showed significant selectivity over structurally analogous molecules. Therefore, both high sensitivity and selectivity were realized in such novel off-on sensor. Extension of this concept to other biologically relevant fluorescent templates could lead to potentially useful applications. Chapter 5. Design of New Template Binding Cross-linker. In molecularly imprinted polymers (MIP), high cross-linking density (~80 to 90 mole percent) is essential to ensure high selectivity, which limits the functional (binding) monomer to about 10-20 mole percent. Methacrylic acid (MAA) and ethyleneglycol dimethacrylate (EGDMA) are the most common combination of functional monomer and cross-linker, respectively, used in molecular imprinting. Generally a molecularly imprinted polymer made with this combination, contains only 10-20% binding sites. This limitation of binding site density is an aspect that has largely been overlooked. In order to improve the efficiency of MIP materials by enhancing the number of binding sites, a new cross-linking monomer (CYDI, 1) with two carboxylic acid groups was designed and synthesized by coupling itaconic anhydride with cyclohexane dimethanol (Figure 5). Figure 5. Structures of relevant molecules. The new functional group bearing cross-linking monomer (1) Itaconate ester of cyclohexanedimethanol (CYDI), the template (2) theophylline (Theop) and the structural analogue of template (3) caffeine (Caff). This new cross-linking monomer was then employed for preparing molecularly imprinted polymer using a drug molecule, theophylline (Theop 2, a bronchodilator) as the template. Seven molecularly imprinted polymers were synthesized with different ratios of CYDI and EGDMA, keeping the cross-linking density constant. The binding efficiency and the selectivity of these imprinted polymers were thoroughly investigated. It was seen that while saturation binding values for theophylline increased continuously with functional cross-linker (CYDI) content, the optimum selectivity with respect to analogous substrate, caffeine, was attained at 40 mol% CYDI. These studies suggest that the approach of using functional group containing cross-linkers could lead to improved MIP performance.

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Shih, Chi-Dong, and 石啟東. "Sythesis of moleculary imprinted polymer for analysis of camptothecin." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/81384657926358899903.

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碩士
南台科技大學
化學工程與材枓工程系
97
Abstract Molecularly imprinted polymers were prepared with camptothecin as template and acrylamide and methacrylic acid as monomer or comonomer. They were found that four MIP of EAMC-5, EAMD-5, TAMC-5 and TAMD-5 had higher adsorption capacities of captothecin compared with MIP without camptothecin template. The equilibrium data were applied to three equilibrium isotherms and the Langmuir model agreed very well experimental data. The mean adsorption energies of four MIPs form Dubinnin- Radushkevich isotherm reflected that the adsorption was predominant to be chemisorption process. Thermodynamic parameters of changes in free energy (ΔG0), enthalpy (ΔH0) and entropy (ΔS0) were also determined. While the temperature was increased, the camptothecin adsorption on MIP showed to be exothermic. Kinetics study was found to be followed the second order. The MIPs were characterized by TGA and SEM. They revealed that the surface structures and thermodynamic properties were dependent on the kinds of solvents.

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Granger, Genevieve. "Détection de matériaux énergétiques dans les eaux naturelles souterraines par spectroscopie de résonance des plasmons de surface portable." Thèse, 2017. http://hdl.handle.net/1866/19344.

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Au cours des dernières années, les matériaux énergétiques, tels que le 2,4,6-trinitrotoluène (TNT) et le 1,3,5-trinitro perhydro-1,3,5-triazine (RDX), ont été utilisés lors des activités d’entrainement militaire, ayant un impact potentiel sur l’environnement, les bases militaires, la population environnante, la faune et la flore. Sur les champs de tir, les sols à proximité des cibles et autour des positions de tir nécessitent une surveillance particulière, puisqu’il est possible de trouver une importante quantité de résidus d’explosif qui peuvent être transportés vers les eaux de surface et des eaux souterraines avec les précipitations. Toutefois, la procédure actuelle pour détecter des matériaux énergétiques dans l'eau naturelle est complexe, longue, nécessite un personnel hautement spécialisé et augmente le risque de contamination croisée. Par conséquent, il est difficile d'assurer un contrôle rapide et continu des contaminants. En fait, l'objectif des travaux présentés dans ce mémoire est de développer une technique pour identifier et quantifier les explosifs et leurs produits de dégradation dans les eaux naturelles. En outre, ce test doit être in situ, en continu, peu coûteux et rapide. La résonance des plasmons de surface (SPR) a été donc utilisée pour quantifier les matériaux énergétiques. Une matrice de bis-aniline réticulée avec des nanoparticules d’or (AuNPs) est utilisée en tant que polymère à empreinte moléculaire (MIP) sur le film d'or pour capturer sélectivement le composé d’intérêt. L'association de la molécule d’intérêt, tel que le TNT ou RDX, au MIP par interactions π-donneur-accepteur permet la détection d'explosifs suite aux changements d’indice de réfraction sur la sonde. Le couplage entre les plasmons des AuNPs et de la couche d'or peut également augmenter les signaux SPR. Le test optimisé a ensuite été utilisé sur une base militaire canadienne. L'utilisation de cet essai à base de MIP fournit un outil pour l'extraction et la pré-concentration de TNT ou RDX à la surface d’une sonde SPR et permet leur détection en continu de faibles concentrations dans les eaux naturelles.
Over the last few years, energetic materials such as 2,4,6-trinitrotoluene (TNT), 1,3,5-trinitroperhydro-1,3,5-triazine (RDX) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) have been used and show a probable environmental impact on military bases, the surrounding population, fauna and flora, caused by military training involving munitions. On shooting ranges, soils near the firing positions and around targets require special monitoring, since the quantities of explosives residues found can be significant, and these compounds can be transported to surface water and groundwater by precipitation. However, the current procedure to detect energetic materials in natural water is complex, long and poorly adapted to. These operations require highly specialized personnel and increase the risk of cross contamination. Therefore, it is difficult to ensure a fast and continuous monitoring of the contaminants. Here, the objective is to develop a technique for identifying and quantifying explosives and their degradation products in natural water. Also, this test has to be in-situ, inexpensive and fast. Surface plasmon resonance (SPR) has been proposed to probe energetic materials. A bis-aniline-cross-linked gold nanoparticles (AuNPs) matrix is used as a molecular imprinted polymer (MIP) on gold film to selectively capture the target compound. The association of the target such as TNT or RDX to the MIP with π-donor-acceptor interactions have allow the detection of explosives by following SPR refractive changes. Plasmon coupling effects between the AuNPs and the gold film could also increase the SPR signals. The optimal sensor was then used on site to detect RDX in underground water of a Canadian military base. The utilisation of MIP based assay will provide a tool for the extraction and pre-concentration of TNT or RDX on the detector’s surface and will allow the detection of lower concentrations in natural water.

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46

Cruz, Victoria Franco. "Supercritical extraction of polyphenols from different vegetable matrices and their retention and recovery using molecularly imprinted polymers." Master's thesis, 2019. http://hdl.handle.net/10198/19539.

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Dupla diplomação com a UNIFACS - Universidade Salvador
Different kinds of vegetable residues abundant in Trás-os-Montes region, namely walnut leaf, walnut shell, almond shell, grape marc, olive leaf and onion shell (a worldwide available biomass) were considered as possible sources of polyphenols. Extraction with supercritical carbon dioxide (at T=40 °C, P=160 bar and ethanol as co-solvent), ultrasound extraction and Soxhlet extraction were alternatively used to obtain mixtures containing these bioactive compounds. Aiming at the subsequent separation and concentration of the polyphenols from the complex extracts obtained, molecularly imprinted polymers (MIPs) were used as a kind of engineered adsorbents. MIP particles synthesized by precipitation polymerization with 4-vinylpyridine (4-VP) as functional monomer and quercetin as template were applied in the retention and recovery of the polyphenols. Comparative studies with commercial polymeric adsorbents (namely with the resin DAX8) were also performed. Batch adsorption, solid phase extraction (SPE) and operation in HPLC columns packed with the adsorbents were considered in these uptake/release studies. The identification and quantification of polyphenols was performed using Liquid Chromatography with Mass Spectroscopy and Diode Array Detector (LC-MS-DAD) and also with the more straightforward HPLC-DAD technique. With the supercritical CO2 (SCCO2) extraction conditions used, the richest phenolic profiles were obtained with onion shell and almond shell. Indeed, quercetin and many quercetin analogues (e.g. quercetin-O-glucoside, quercetin-O-diglycoside, quercetin dimer-O-hexoside, etc) were identified in these onion shell extracts, while quercetin, isorhamnetin-3-O-rutinoside or catechin (e.g.) were identified in the almond shell extracts. However, in spite of a similar composition, a higher phenolic content was measured for extracts obtained with the ultrasounds (US) or Soxhlet (SHOX) extraction, comparatively to supercritical CO2 extraction (e.g. around 10 mg/g of total phenolic compounds with US and SHOX extraction and 1 mg/g with SCCO2 for onion shell extracts, in a dry basis of plant residue). Benefits of molecular imprinting in the designing of tailored adsorbents to be used with downstream processing of polyphenols were evidenced in this research. Indeed, a very high polyphenol retention was here shown to be possible with MIPs, even when solvents with low water content are used (e.g. ethanol/water 80/20). Thus, the hydrophobic interactions, that usually is the main driving force for adsorption with common synthetic resins, is not the unique mechanism allowing the retention of these bioactive compounds in the synthesized molecularly imprinted polymer networks. The functionalization of the materials (here with pyridyl functional groups) and the creation of imprinted tailor-made cavities (promoting analogue mechanisms to antigen/antibody or substrate/enzyme binding) were congenial for the improved performance of the MIPs. Additionally, the manipulation of the particles morphology (through precipitation polymerization), allowing a facile binding accessibility (e.g. due to surface imprinting) should also contribute for the observed superior performance of the MIPs in polyphenols retention. The distinctive features of the MIP adsorbents were here demonstrated through the direct processing of plant extracts without water addition (e.g. using an ethanol/water 80/20 onion shell extract). A polyphenol-enriched fraction, containing quercetin and analogue molecules, was recovered at the end with the minimization of thermal treatments (only alcohol evaporation is needed if a dry residue is wanted). Thus, the simplification of the adsorption/desorption process was achieved and energetic costs can also be cut down (besides the minimization of the possible thermal degradation of the bioactive compounds). Summing up, this research demonstrate that MIP adsorbents can be helpful in the design of new and more flexible adsorption processes (e.g. working with a wider range of water content), aiming at the valorization of polyphenols present in plant extracts. Food industry, pharmaceutics and cosmetics are examples of applications fields for the principles here outlined.
Diferentes tipos de resíduos vegetais abundantes na região de Trás-os-montes, como a folha de nogueira, a casca de noz, a casca de amêndoa, o bagaço da uva, a folha de oliveira e a casca da cebola (uma biomassa disponível de forma mais abrangente no planeta) foram considerados como possíveis fontes de polifenóis. A extração com dióxido de carbono supercrítico (usando T = 40 °C, P = 160 bar e etanol como co-solvente), a extração por ultrassom e a extração por Soxhlet foram alternativamente utilizadas para obter misturas contendo esses compostos bioativos. Visando a subsequente separação e concentração dos polifenóis dos extratos complexos obtidos, polímeros molecularmente impressos (MIPs) foram utilizados como uma espécie de adsorventes. Partículas de MIPs sintetizadas através de polimerização por precipitação com 4-vinilpiridina (4-VP) como monômero funcional e quercetina como molécula modelo foram aplicadas na retenção e recuperação dos polifenóis. Também foram realizados estudos comparativos com adsorventes poliméricos comerciais (como a resina DAX-8). A adsorção em batch, a extração em fase sólida (SPE) e a operação em colunas de HPLC empacotadas com os adsorventes foram consideradas neste estudo para a retenção e libertação dos compostos fenólicos. A identificação e quantificação de polifenóis foi realizada utilizando cromatografia líquida com espectroscopia de massa e detector de diodo array (LC-MS-DAD) e também com a técnica mais direta de HPLC-DAD. Com as condições de extração com CO2 supercrítico (SCCO2) utilizadas, os perfis fenólicos mais ricos foram obtidos com a casca da cebola e a casca de amêndoa. Foram identificadas quercetina e muitos análogos de quercetina (por exemplo, quercetina-o-glucosídeo, quercetina-o-diglicosídeo, quercetina dimer-o-hexoside, etc.) nos extratos da casca da cebola, enquanto quercetina, isorhamnetin-3-O-rutinoside ou catequina, por exemplo, foram identificados nos extratos da casca de amêndoa. No entanto, apesar de uma composição semelhante, um maior teor de compostos fenólicos foi medido para extratos obtidos com a extração por ultrassom (US) e Soxhlet (SHOX), comparativamente a extração com CO2 supercrítico (por exemplo, cerca de 10 mg/g de compostos fenólicos totais com as extrações US e SHOX e 1 mg/g com SCCO2 para extratos de casca de cebola, numa base seca de resíduo vegetal). Os benefícios da impressão molecular na concepção de adsorventes adaptados a serem utilizados com o processamento a jusante de polifenóis foram evidenciados nesta
pesquisa. De fato, foi possível mostrar uma elevada retenção de polifenóis com MIPs, mesmo quando solventes com baixo teor de água são utilizados (por exemplo, etanol/água 80/20). Assim, as interações hidrofóbicas, que geralmente são a principal força motriz para a adsorção com resinas sintéticas comuns, não é o único mecanismo que permite a retenção desses compostos bioativos nas redes de polímeros sintetizados com a técnica de impressão molecular. A funcionalização dos materiais (com grupos funcionais piridil) e a criação de cavidades impressas por medida (promovendo mecanismos análogos à interação antígeno/anticorpo ou substrato/enzima) foram benéficas para o melhor desempenho dos MIPs. Adicionalmente, a manipulação da morfologia das partículas (através da polimerização por precipitação), permitiu uma fácil acessibilidade aos sítios de adsorção (por exemplo, devido à impressão à superfície) que deve igualmente contribuir para o desempenho superior observado com os MIPs na retenção de polifenóis. As características distintivas dos MIPs como adsorventes foram aqui demonstradas através do processamento direto de extratos de plantas sem adição de água (por exemplo, usando um extrato da casca da cebola em etanol/água 80/20). Uma fração enriquecida com polifenóis, contendo quercetina e moléculas análogas, foi recuperada no final com a minimização dos tratamentos térmicos (somente a evaporação do álcool é necessária se um resíduo seco for pretendido). Assim, a simplificação do processo de adsorção/dessorção foi alcançada, e os custos energéticos também poderão ser potencialmente reduzidos (para além da minimização de uma possível degradação térmica dos compostos bioativos). Resumindo, esta pesquisa demonstra que os MIPs como adsorventes podem ser úteis na concepção de novos processos de adsorção e mais flexíveis (por exemplo, permitindo trabalhar com uma quantidade de água mais ampla relativamente aos adsorventes comuns), visando a valorização dos polifenóis presentes nos extratos vegetais. A indústria alimentícia, farmacêutica e cosmética são exemplos de campos de aplicações para os princípios aqui delineados.
This work was supported by the project “AIProcMat@N2020—Advanced Industrial Processes and Materials for a Sustainable Northern Region of Portugal 2020”, with the reference NORTE-01-0145-FEDER-000006, supported by Norte Portugal Regional Operational Programa (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (ERDF) and of Project POCI-01-0145-FEDER-006984—Associate Laboratory LSRE-LCM funded by ERDF through COMPETE2020— Programa Operacional Competitividade e Internacionalização (POCI)—and by national funds through FCT—Fundação para a Ciência e a Tecnologia.

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