Дисертації з теми "Systèmes à libération contrôlée"
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Mauduit, Jacques. "Nouveaux systèmes antibiotiques à libération contrôlée à base de gentamycine et de polymères biorésorbables." Rouen, 1991. http://www.theses.fr/1991ROUES008.
Lemut, Josiane. "Utilisations biomédicales des silicones : application à un système à libération contrôlée." Clermont-Ferrand 1, 1990. http://www.theses.fr/1990CLF14036.
Yang, QiaoWen. "Systèmes polymériques à base de dispersion aqueuse administrés par voie orale pour la libération contrôlée du principe actif." Lille 2, 2009. http://www.theses.fr/2009LIL2S045.
Estebe, Jean-Pierre. "Évaluation pré-clinique de systèmes thérapeutiques microparticulaires à libération contrôlée de bupivacaine dans les techniques d'anesthésie loco-régionale périphérique." Rennes 1, 2001. http://www.theses.fr/2001REN1BA55.
Ongkasin, Kanjana. "Elaboration de dispositifs médicaux ophtalmiques à libération contrôlée de médicaments par imprégnation supercritique." Thesis, Aix-Marseille, 2019. http://www.theses.fr/2019AIXM0536.
Supercritical CO2 technologies are arisen as green and eco-responsible alternatives for drug formulation and medical device processing. The present PhD work aims to develop innovative ocular therapeutic medical devices to mitigate two post-operative complications of cataract surgery, endophthalmitis and posterior capsule opacification. Among other processes, supercritical impregnation was selected to load commercially available intraocular lenses (IOLs) commonly used in cataract surgery with ophthalmic drug components. A targeted action of drug molecules can be therefore achieved through a sustained release directly at the potential affected zones without requiring subsequent medical interventions. Supercritical impregnation of foldable hydrophobic acrylic IOLs was studied by varying the operating conditions of pressure (8 to 25 MPa), temperature (308 to 328 K) and impregnation duration (30 to 240 min). The influence of using ethanol as a co-solvent was also evaluated. In vitro drug release kinetics were studied and used to determine the impregnation yields. In order to rationalize the influence of the concomitant phenomena governing impregnation, thermodynamic behaviors of the involved systems, polymer/CO2 and drug/CO2 were studied. {Ex vivo} implantation of methotrexate impregnated IOLs on human donor capsular bags shown fibrosis reduction by inhibiting epithelial-mesenchymal transformation highlighting the potential of the innovative sustained-release drug-delivery IOLs to become of clinical relevance
Genty, Muriel. "Caractérisation des dispersions complexes de sphérulites et évaluation de leur potentiel pour la libération contrôlée et la protection d'espèces encapsulées : comparaison avec d'autres systèmes lipidiques." Paris 11, 2003. http://www.theses.fr/2003PA114807.
Jean, Baptiste Elixène. "Amélioration des propriétés antibactériennes et anticoagulantes des prothèses vasculaires en polyester par immobilisation et libération contrôlée de principes actifs." Thesis, Lille 2, 2012. http://www.theses.fr/2012LIL2S043/document.
Synthetic vascular prosthesis likewise vascular endoprosthesis are prone to several complications after implantation into the human body. Infections, thromboses and late occlusions are the most challenging and the most common, leading to serious clinical consequences that are sometimes lethal. Management of those complications is still fraught with tremendous difficulties justifying the economic burden and the continuous efforts in research development for improving vascular prosthetic materials. This research investment is, however, yet to yield any great clinical advance. Previous studies conducted in our research laboratory have led to the development of polyester vascular prostheses coated with a polymer of hydroxypropyl-β-cyclodextrin. This was achieved in order to increase the loading and eluting capacities of these vascular prostheses towards several antibiotics. In the current works, we sought to determine the optimal conditions for effective controlled release of three antibiotics from those prosthetic platforms. We have also evaluated their efficacy in both in vitro and in vivo models of vascular infections. This was carried-out against nine different bacteria strains that are among the most common in human vascular infections. Moreover, we have assessed in vivo their safety, their healing properties, their systemic toxicity and their biocompatibility in the prospect of clinical application.The above-mentioned drug delivery system has been proved to be effective in releasing in situ the selected antibacterial agents over a seven-day desorption period in human plasma. Optimal batch concentration and time for prosthetic immersion into the antibiotic solutions were well compatible with current surgical practice standards. A bactericidal activity evidenced by significant reduction of bacterial adhesion, growth and proliferation was revealed when compared to appropriate controls in the various tested vascular infection models. We have also studied antibacterial molecules alone or in combination. In this latter setting, no antagonistic effects were depicted. This provides a unique opportunity to customize local antibiotic treatment delivered in situ from vascular device fabrics and to adapt it to the evolving ecology of both monomicrobial and polymicrobial vascular prosthetic infection. The polyester vascular prostheses coated with a polymer of hydroxypropyl-β-cyclodextrin were proved in vivo safe and demonstrated excellent biocompatibility, healing properties and tissue integration without any signs of systemic toxicity. [...]
Kalaji, Mohamed Nader. "Élaboration d'un système de libération contrôlée des facteurs de croissance FGF-2 et TGF-β1 en vue de leur utilisation en odontologie conservatrice et endodontie". Phd thesis, Université Claude Bernard - Lyon I, 2010. http://tel.archives-ouvertes.fr/tel-00881178.
Kalaji, Mohamed Nader. "Élaboration d’un système de libération contrôlée des facteurs de croissance FGF-2 et TGF-β1 en vue de leur utilisation en odontologie conservatrice et endodontie". Thesis, Lyon 1, 2010. http://www.theses.fr/2010LYO10224/document.
The purpose of this work was to investigate the effect of FGF 2 and TGF-β1 on the early steps of dentin regeneration using microencapsulation of theses factors into a microparticles matrix to ensure growth factors protection and to provide bioactive sustained release in contact with dental pulp cells and then the application of the obtained microparticles in direct pulp capping using a culture model of entire tooth. This work involves the optimization of technical means used to achieve encapsulation of TGFβ1, FGF-2 using the poly (lactic-glycolic acid) PLGA. Physicochemical and colloidal characterization of microspheres shows that the microparticles retain their physicochemical characteristics after drying and re-suspended in water. The double emulsion method was used to separately encapsulate (FGF-2) and (TGFβ1). Microparticles morphology, loading, shelf life, potential toxicity and release kinetics were studied. Then the proliferation of dental pulp cells was examined in contact with microparticles. Biological studies show no toxic effect of particles on pulp fibroblasts. Growth factors have kept their specific biological activity. A culture model of human entire tooth was used to achieve the application of microparticles as a dental direct capping material to confirm their biological activities ex vivo. These microparticles can be useful in studies of early steps of dentin regeneration, activation and migration of progenitor cells in dental pulp
Qnouch, Adam. "Implants en silicone pour le traitement de l’oreille interne." Thesis, Université de Lille (2018-2021), 2021. http://www.theses.fr/2021LILUS060.
The inner ear is the organ responsible for auditory perception and the maintenance of balance.When these perception systems are disrupted or damaged, various inner ear diseases can occur, such as deafness.The administration of an active ingredient into the inner ear by the classical routes (oral, intravenous, intramuscular) does not achieve sufficient concentrations to treat a disease.Therefore, a local and single administration can provide great benefits. The application of a hearing aid such as a cochlear implant may be necessary if deafness persists. A cochlear implant converts sound into an electrical signal in the same way that hair cells do, which can be translated back into auditory perception in the brain. The electrode is connected to an amplifier implanted behind the patient's ear. Implanting an electrode in the scala tympani of the inner ear can then help to restore sensory perception.As these cochlear implants are made of silicone, it is possible to load them with active ingredients. The release of active ingredient from silicone can be maintained for years: Silicone loaded with dexamethasone has been successfully implanted in pacemakers. After 10 years of implantation, an improvement in electrode function is observed compared to pacemakers not loaded with active ingredient. To adjust the release of the active ingredient, several parameters can be varied. In addition, the geometry and dimensions of the system can have a great influence on the release as they impact the length of the "path" the active ingredient has to travel to be released. This is particularly important given the rather hydrophobic nature of the polymer which slows down the penetration of water into the matrix and consequently the release of the active ingredient.The main objectives of this thesis are:- To study the long term in vitro release of dexamethasone loaded cochlear implants- To develop and characterise silicone matrices combining dexamethasone and dexamethasone phosphate
Swed, Amin. "Encapsulation de protéines dans des systèmes polymériques particulaires par des procédés sans solvants toxiques pour l'ingénierie tissulaire du cartilage." Thesis, Angers, 2015. http://www.theses.fr/2015ANGE0039/document.
The aim of this work is to develop polymeric particulate systems loaded with transforming growth factor (TGF-β1) for cartilage tissue engineering application. First, nanoparticles of PLGA (poly(lactic-co-glycolic) acid) were generated using a phase separation method while PLGA microparticles were prepared by an emulsification/extraction process in CO2 medium. Interestingly, non-toxic, non-volatile injectable solvents were used in the formulation processes. The prepared polymeric systems were characterized; spherical particles with sustained release were obtained and satisfactory encapsulation efficiency was achieved with preservation of the growth factor bioactivity. TGF-β1-loaded particles were then incorporated within injectable silanized cellulose-based hydrogel (Si-HPMC) containing stem cells. The obtained biomaterial was characterized in terms of morphology, rheological properties and release study. The local and sustained release of TGF-β1 could induce survival, proliferation and differentiation of stem cells into chondrocytes which may promote cartilage regeneration. To conclude, the elaborated hybrid biomaterial has a promising potential for cartilage tissue engineering
Brochart, Hervé. "Étude de la diffusion d'un principe actif à travers une membrane polymérique poreuse constituée de non-tissé : application au développement d'un système réservoir à libération contrôlée destiné à un usage vétérinaire." Paris 11, 1994. http://www.theses.fr/1994PA114807.
Delplace, Céline. "Microparticules à libération contrôlée : nouveaux polymères et importance des conditions de libération." Thesis, Lille 2, 2012. http://www.theses.fr/2012LIL2S007.
Poly(lactic-co-glycolic) acid (PLGA)-based microparticles represent an attractive choice to sustain drug release over periods ranging from a few days up to several months, while ensuring good biocompatibility and complete biodegradability. Recently, tremendous efforts have been devoted to improve the properties of these copolymers by introducing functional groups along the polymeric chain, with the aim of modulating the drug release.On the one hand, the main objective of this work was to investigate the potential application of new functionalized copolymers bearing pendant carboxyl groups (PLA-co-PBED), as controlled drug delivery device. In this study, apomorphine was encapsulated as a model drug. Its therapeutic effect is limited due to its very short half-life and its strong emetic effect. Consequently, biodegradable microparticles would offer the advantage of improving therapeutic efficiency and compliance, by reducing administration frequency and minimizing systemic side effects. Apomorphine-loaded, PLA-co-PBED-based microparticles were prepared using an emulsion method. Microparticles based on PLGA 50:50 of different molecular weights were used as a reference. The obtained microparticles were characterized using various techniques. The residual content of dichloromethane (used as organic phase during microparticle preparation) was quantified and the in vitro release of apomorphine was studied. Interestingly, the functionalized polymers bearing free-carboxylic groups led to higher drug encapsulation efficiencies, lower residual contents of dichloromethane and different drug release patterns. These results suggest a promising application of these functionalized polymers to control drug release. Furthermore, the impact of the formulation parameters on the resulting physico-chemical properties of microparticles was studied. The main objective was to optimize the encapsulation efficiency, while minimizing initial burst release, to avoid toxic concentration peaks, and thus potential side effects. In this matter, some formulation parameters were varied during the preparation of microparticles based on PLGA 50:50 of 10 kDa. Optimal parameters were selected to achieve a zero-order apomorphine release over 10 days.On the other hand, it is well known that the in vitro drug release studies are crucial for the development of PLGA-based microparticles. However, as no standardized method has yet been established by authority agencies, very different methods are used in practice and their consequences on the resulting drug release kinetics are not well understood. Consequently, this work was intended to evaluate the impact of the experimental conditions on the resulting drug release kinetics from PLGA-based microparticles. Frequently applied setups were used. Different model drugs were encapsulated at different initial drug loadings. Various techniques were used to characterize the resulting formulations. Mathematical modeling was applied to better understand the observed phenomena. These results showed that the impact of the experimental conditions can be negligible or significant, depending on the type of formulation and the experimental setup. The observed differences could partially be explained by differences in the underlying drug release mechanisms. It can be concluded that great care must be taken when drawing conclusions from in vitro drug release measurements
Nyalosaso, Likoko Jeff. "Synthèse et caractérisation de sphères monodisperses de silice à porosité radiale (multi)fonctionnelles et étude de leur performance en catalyse en phase liquide et en vectorisation de principes actifs." Thesis, Montpellier 2, 2011. http://www.theses.fr/2011MON20218.
A novel approach of synthesis has been developed in order to control simultaneously the morphology, size and textural parameters of silica particles, as well as to incorporate one or more functional groups in the pore walls. In this approach, based on the modified Stöber method and in-situ functionalization, emphasis is put on the spherical morphology, the particle monodispersity, the radially disposed porous structure, and the appropriate dispersion and accessibility of surface functional groups. Two potential applications have been selected so as to verify the feasibility of the approach. In view of materials use for heterogenous catalysis in the liquid phase, the monodisperses mesoporous silica spheres were derivatized with metallic species (e.g., Al and Cu) by direct incorporation in the synthesis stage. The second type of applications concerned the use of silica spheres as sensitive nanomachines for the controlled drug release and required grafting of appropriate organic molecules onto the silica surface
FEITOSA, Leonardo Falcão. "Síntese e caracterização de matriz porosa quitosana/fentanil para implementação como sistema de liberação controlada de fentanil." Universidade Federal de Campina Grande, 2014. http://dspace.sti.ufcg.edu.br:8080/jspui/handle/riufcg/364.
Made available in DSpace on 2018-04-11T15:06:17Z (GMT). No. of bitstreams: 1 LEONARDO FALCÃO FEITOSA - DISSERTAÇÃO PPG-CEMat 2014..pdf: 2258061 bytes, checksum: cdc233909fd365937aacd1ef5fa7c2cd (MD5) Previous issue date: 2014-12-29
Na terapia medicamentosa convencional o fármaco é administrado através de uma forma farmacêutica e produz um nível tecidual do fármaco que não se mantêm dentro da faixa terapêutica por um período prolongado de tempo. Desta forma, o êxito do tratamento vai depender de vários fatores como dosagens precisas e frequentes em horários específicos pré-determinados e adesão do paciente à terapêutica de modo que, a não obediência ao esquema terapêutico, pode resultar em utilização do fármaco em faixa não efetiva ou em níveis tóxicos Devido a grande problemática da manutenção de níveis séricos de fármacos no organismo humano, principalmente quando se tratam se fármacos relacionados ao tratamento de dores de moderadas a intensa, este trabalho propõe o desenvolvimento de membranas porosas a base de quitosana, que é um polímero natural biocompatível, capazes de promover a liberação controlada de fentanil. As matrizes obtidas foram caracterizadas por: MO, MEV, EDS, FTIR, DRX, Ensaio de Intumescimento, Ensaio de Biodegradação e Ensaio de Citotoxicidade. Por MO e MEV verificou-se uma superfície com poros aparentemente interconectados. A partir da análise por EDS pode-se verificar os elementos componentes da quitosana e do fármaco. Por FTIR e DRX notou-se a não alteração dos grupos funcionais e cristalinidade, respectivamente, do material devido a incorporação do fármaco. Baseado nos ensaios de intumescimentos e biodegradação verificou-se a capacidade de controlar as variáveis: razão de intumescimento e taxa de degradação exclusivamente pela variação da concentração de quitosana na membrana porosa. Verificou-se no ensaio de citotoxicidade que as membranas, mesmo com a incorporação do fármaco, não apresentaram citotoxicidade. Baseado nos resultados obtidos pôde-se concluir que é possível sintetizar uma matriz polimérica com promissoras propriedades para carrear fármaco e para testes in vivo.
In conventional medical therapy the drug is administered via a dosage form and produces a tissue level of the drug that is not maintained within the therapeutic range over an extended period of time. Thus, the success of the treatment will depend on several factors such as accurate and frequent dosing at predetermined specific times and patient adherence to therapy so that the non-compliance to the treatment regimen can result in use of the drug in not effective range or toxic levels Due to the great problem of maintaining serum levels of drugs in the human body, especially in the case if drugs related to the treatment of moderate to severe pain, this paper proposes the development of porous membranes chitosan base, which is a biocompatible natural polymer, capable of promoting the controlled release of fentanyl. The matrices obtained were characterized by: OM, SEM, EDS, FTIR, XRD, Swelling test, biodegradation test and Cytotoxicity Assay. For OM and SEM there was apparently a surface with interconnected pores. From the EDS analysis can verify the elements of chitosan and drug. FTIR and XRD noted not to change functional groups of crystallinity and, respectively, of the material due to the incorporation of the drug. Based on swellings and biodegradation tests verified the ability to control the following variables: swelling ratio and degradation rate solely by varying the concentration of the chitosan porous membrane. It was found that the cytotoxicity assay the membranes, even with the incorporation of the drug did not show cytotoxicity. Based on the results obtained it was concluded that it is possible to synthesize a polymer matrix with promising properties to adduce drug and in vivo tests.
Bautzova, Tereza. "Les systèmes microparticulaires pour la libération colonique." Phd thesis, Université de Franche-Comté, 2012. http://tel.archives-ouvertes.fr/tel-00830507.
Guglielmi, Marie-Anne. "Elaboration d'un nouveau concept de libération contrôlée de composés phytopharmaceutiques par combinaison zéolithique." Poitiers, 2010. http://www.theses.fr/2010POIT2345.
The number of available active substances to protect plants has decreased considerably for some years and it is important to use those which remain on the market in a more rational way, notably by reducing their environmental impact. The objective of this work lies in working out formulations for the controlled release of xylem systemic pesticidal compounds by combining them with zeolites. This will give the plant a systemic phytosanitary compound active over the necessary period for its protection, with minimal environmental impact (volatilisation or leaching). For this, the first part of the work has revolved around the adsorption of phytopharmaceutical compounds, judiciously chosen from the faujasite zeolites. This study quickly resulted in the preferential use of hydrophobic zeolites (raised correlation Si/Al), to find an environment-friendy procedure using water as solvant. In addition, this adsorption is totally controlled and allows for formulations at various concentrations (loads). The second part of this work revolved around the study of the kinetics of the desorption of the active ingredient. The importance of the load and the size distribution of the zeolite on the release of the active matter has thus been demonstrated. Biological tests on the formulations thus achieved, have resulted in the 3rd and last part, during the course of which the efficiency of the zeolitic combinations have been proven both in a controlled atmosphere as well as in the open field
Gontard, Gwenaëlle. "Synthèse de nanoconjugués PEG-PLA pour des applications biomédicales : libération contrôlée et Imagerie." Thesis, Toulouse 3, 2016. http://www.theses.fr/2016TOU30279.
This PhD thesis is based on a joint between Sanofi in Vitry-sur-Seine and LHFA. This work consists in the development of new nanovectors based on biodegradable and biocompatible polymerics conjugate that enable to encapsulate, transport and deliver therapeutic agents. Previous works in the laboratory have shown that the release of hydrophobic drugs, such as Cabazitaxel, a taxane derivative, could be controlled by the architecture of the conjugated PEG-PLA. In the first chapter, a study was realized to improve the release kinetics of the drug, taking advantage of the difference of pH between healthy and cancerous tissue. Different linkers (linking the drug to the copolymer) having a pH dependent behavior have been studied, such as hydrazone, acetal and β-thiopropionate. The boronic ester bonding, dynamic function of pH, was also studied in order to destroy the NP and indirectly improve the release of drug. The synthesis and the evaluation of various conjugates have shown that the amphiphilic polymeric structure of the conjugates significantly inhibited the expected pH-dependent behavior. In the second chapter, several technologies such as targeting or imaging were studied. The influence of the Y and L-shape on the recognition and imaging properties was analyzed. The Y-shape offers advantages like the amount of ligand required for optimal active targeting and better visualization, in comparison with the results obtained with the L conjugates. The method of co-nanoformulation allowed to adjust the ligand amount or imaging probe within the NPs. In the third chapter, the synthesis and efficiency of (bi)pyridinium salts as catalysts for the ROP of ε-caprolactone are presented. A collaborative behavior with dication bipyridiniums is bearing two hydrogen bonds (IHBD) was demonstrated for the activation of the ε-caprolactone, with greater ROP activities compared to systems involving the participation of only one H bond. The best systems were evaluated in more details and allowed access to polymers with a molecular weight of up to 13 000 g / mol
Porte, Karine. "Les composés mésoioniques : de nouveaux outils pour la libération contrôlée de principes actifs." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS253.
Recently, our laboratory has discovered a click and release reaction involving iminosydnones, a family of mesoionic compounds, and cyclooctynes. This bioorthogonal reaction occurs via a two step process: a [3+2] cycloaddition followed by a retro Diels-Alder, to give two new compounds: a click product and a release product.The main goal of this work is to improve the kinetic of the reaction between these two partners in order to use it as a powerful tool for in vivo drug delivery. Three strategies were developed during this thesis to optimize this reaction system: the study of a structure/reactivity relationship of the iminosydnone partner regarding the bioorthogonal reaction; the development of micelles built by amphiphiles containing an iminosydnone moiety as a cleavable linker, strategically located between the hydrophobic and the hydrophilic part of the compound and finally, the use of molecular recognition between two peptide nucleic acids (PNA) complementary strands
Boissenot, Tanguy. "Nanocapsules théranostiques pour l’imagerie par IRM-19F et la libération contrôlée par ultrasons." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLS078.
We have developed theranostic nanocapsules combining a diagnostic moiety to improve tumor detection and a therapeutic moiety to treat them. These nanocapsules are composed of a polymer shell of PLGA-PEG and a core of a perfluorocarbon, namely perfluorooctyl bromide, detectable by 19F-MRI. Paclitaxel, a cytotoxic drug, was encapsulated in an attempt to reduce side-effects associated with excipients such as Cremophor® used in the commercial formulation (Taxol®). We optimized encapsulation of paclitaxel into nanocapsules by varying formulation parameters to prevent or limit paclitaxel recrystallization and nanocapsule aggregation. The optimized formulation was tested in vitro on CT-26 colon cancer cells and showed similar cytotoxicity as compared with Taxol®. Paclitaxel pharmacokinetics and biodistribution were evaluated in nude mice bearing CT-26 tumors comparing nanocapsules with Taxol®. For nanocapsules, pharmacokinetic parameters are improved leading to a longer circulation and resulting in an enhanced accumulation in tumors, as confirmed by 19F-MRI. In terms of efficacy, this enhanced passive targeting allows a slower tumor growth in animals treated with paclitaxel-loaded nanocapsules compared to PBS and Taxol®. Ultrasound were also used to further improve tumor targeting. We showed that when applying a safe ultrasound sequence, tumor growth was slower on our tumor model. In vitro studies showed that this decreased growth is due to mild hyperthermia favoring tumor perfusion and vascular extravasation leading in an enhance accumulation of drugs inside the tumor
Bonnet, Marie. "Libération contrôlée du magnésium par des émulsions doubles : impact des paramètres de formulation." Thesis, Bordeaux 1, 2008. http://www.theses.fr/2008BOR13669/document.
Double water-in-oil-in-water (W/O/W) emulsions are systems in which fat globules are dispersed in an aqueous continuous phase. They provide a compartmented structure that allows the encapsulation of hydrosoluble compounds in the internal aqueous droplets. Nevertheless, the application of multiple emulsions is limited by their thermodynamical instability and the possible diffusion of hydrosoluble matter from one aqueous phase to the other one through the oil layer. In this context, the influence of several formulation parameters (oil nature, hydrophilic emulsifier concentration, oil globule mass fraction, complexation of the encapsulated species) was investigated relatively to magnesium release. All the ingredients used were food grade to match pharmaceutical and food application requirements. Magnesium leakage occurred without film rupturing. A model based on diffusion was proposed in which the rate of release was determined by the permeation coefficient of magnesium across the oil phase, by magnesium chelation and by the osmotic pressure mismatch between the internal and external aqueous phases. The permeation coefficient depended on the chelating agent location and concentration but was poorly influenced by the osmotic pressure. Moreover, the permeation coefficient evolved with time, especially at high oil globule fractions
Batool, Fareeha. "Développement de stratégies innovantes de régénération parodontale via la modulation de la réponse inflammatoire." Thesis, Strasbourg, 2019. http://www.theses.fr/2019STRAJ068.
Control of periodontal infection and inflammation is crucial for optimal periodontal wound healing and regeneration. For this purpose, three different and novel strategies were developed and tested for their impact on periodontal wound healing parameters in vitro and in vivo. Firstly, an ibuprofen-functionalized polycaprolactone (IBU-PCL) membrane was developed as an anti-inflammatory barrier membrane that successfully reduced inflammatory markers expression in gingival cells in vitro and decreased soft tissue inflammation, thus, improving periodontal tissue healing in an experimental periodontitis model in vivo. Secondly, chlorhexidine and ibuprofen containing in-situ forming implant (CHX-IBU ISFI) was developed to target both infection and inflammation that successfully reduced Porphyromonas gingivalis growth and inflammatory response of gingival cells in vitro as well as improved soft tissue periodontal wound healing in vivo. Lastly, a thermosensitive chitosan-based hydrogel functionalized with atorvastatin encapsulated in a nano-emulsion (ATV-KELP NE) was characterized and used to treat an induced bone defect in vivo that resulted in improved soft and hard tissue healing by counteracting infection and modulation of immuno-inflammatory response
Naceur, Tesnim. "Systèmes de files d'attente stratégiques avec information contrôlée." Thesis, Avignon, 2020. http://www.theses.fr/2020AVIG0279.
Faced to queuing systems, customers can make their strategic decisions in order to join or not these systems. An interesting new aspect has emerged and studied in recent years, which is about the impact of current queue-length information on strategic decisions of customers, on the equilibrium and the performance of the system. Customers are not necessarily homogeneous in their behavior and their access to the information, which implies different equilibrium and performances solutions.In some cases, service provider may have an interest to give to customers the system state information and withholding it to others in order to optimize certain objectives. In other cases, obtaining the information is mainly the choice of customers and therefore thay have to decide to inspect or to collect the information or not, according to their constrainsts and their wishes.The main motivation for this thesis is to study the impact of the queue length information on the strategic decisions of customers and to analyze the performance of such strategic queuing systems with controlled information. Our contributions allow to determine the equilibuim and optimize the performance of the systems according to the queue length information. Theoretical and analytical solutions have been proposed to solve the studied problems
Lavielle, Nicolas. "Fabrication de nanofibres et nanoparticules de biopolyesters pour la libération contrôlée d'un composé modèle." Phd thesis, Université de Strasbourg, 2013. http://tel.archives-ouvertes.fr/tel-01063059.
Timbart, Laurianne. "Élaboration de copolymères à base de biopolyesters pour la libération contrôlée de principes actifs." Paris 12, 2005. https://athena.u-pec.fr/primo-explore/search?query=any,exact,990003942950204611&vid=upec.
Poly(3-hydroxyalkanoate)s (P(3-HA)s), are aliphatic biopolyesters with saturated and unsaturated side chains of different lengths. They are produced by a wide range of microorganisms. These biopolymers are biodegradable and biocompatible and can be used for biomedical applications. The aim of the study was to investigate and improve the properties of novel materials based on P(3-HA)s. Copolymers based on P(3-HA)s and semi-crystalline polymers (poly(ε-caprolactone) or poly(lactic acid)) with different structures e. G. Block, graft or statistic copolymers, were synthesized. The presence of unsaturated units on side chains affords us the ability to prepare functionalised copolymers. Block copolymers were used to prepare mucoadhesive nanoparticles by nanoprecipitation and encapsulating doxorubicin. Doxorubicin is a chemotherapeutic agent used to treat bladder disease. The amount of P(3-HA) in the copolymers was used to control the release of doxorubicin
Camargo-Pardo, Javier-Andrés. "Systèmes injectables biodégradables pour la libération prolongée d'ivermectine." Thesis, Nancy 1, 2010. http://www.theses.fr/2010NAN10068/document.
In situ forming injectable systems have been used in the past years to obtain sustained drug release formulations which are easy to prepare. These systems using biocompatible solvents and biodegradable polymers are liquids (solutions or emulsions) that upon injection on the body lead to solid implants (ISI) or microparticles (ISM). These systems are formed in contact with water body fluids by polymer precipitation from the polymeric solution. In this work, ISI and ISM made from lactide and/or glycolide polymers (PLA and PLGA) and different biocompatible solvents were performed to obtain sustained release of ivermectin (IVM), an antiparasitic drug with a low oral bioavailability. In vitro and in vivo drug release profiles from these systems were compared with those from microparticles obtained by the classical simple emulsion/solvent evaporation method, which is difficult to propose in industry because of its multiple steps, high cost and the solvent toxicity. Drug release from simple emulsion/solvent evaporation microparticles was affected by the strong polymer/drug interactions and porosity. Concerning to in situ forming systems, the rate of IVM release was dependent on solvent water solubility and solvent/polymer interactions. The nature of the external phase, water (ISM-O/W) or oil (ISM-O/O), the water solubility of the solvent in the internal phase, phase affinity and IVM/phase affinity determined drug release from ISM. The good stability, the in vitro and in vivo sustained release and the low burst effect of IVM, indicated that ISI and ISM formulated from low hydrosoluble biocompatible solvents such as triacetin are more appropriated to IVM formulation instead of those based on more hydrophilic solvent (N-methyl-2-pyrrolidone and 2-pyrrolidone). These systems are an interesting alternative to conventional IVM formulations
Gasmi, Hanane. "Microparticules à libération controlée : impact du gonflement sur la cinétique de libération de substance active." Thesis, Lille 2, 2015. http://www.theses.fr/2015LIL2S057/document.
The drug release studies from polymeric system such as Poly(lactic-co-glycolic) acid (PLGA)-based microparticles have been widely investigated during recent decades. The main objective of this work is to better understand the mass transport mechanisms controlling the drug release kinetics from PLGA microparticles. New insight was to be gained based on the experimental monitoring of the swelling kinetics of single microparticle. Initially, PLGA microparticles containing different type of drugs (acidic, basic and neutral), such as ketoprofen, prilocaine free base and dexamethasone were prepared using simple oil in water emulsion extraction/evaporation solvent technique. The characterization of the key properties of microparticles was performed using different techniques (optical microscopy, electron microscopy). The gel permeation chromatography was used to determine the molecular weight of PLGA following exposure of microparticles to the release medium at various times to assess the kinetic degradation of the polymer. The X-ray diffraction and differential scanning calorimetry were used to study the physical state of the polymer, drug and drug-loaded microparticles. Release studies have shown two types of release profiles: tri-phasic and more or less mono-phasic profile. The tri-phasic profile is composed of three phases: an initial rapid release phase followed by a constant release which is followed by a second phase of rapid release. In contrast, at the investigated higher initial drug loadings, different release phases could hardly be distinguished: The profiles were more or less mono-phasic. The elucidation of drug release mechanisms was based on the experimental results of the swelling kinetics of single microparticles. As for drug release, distinct phases can be distinguished for microparticles swelling. The transition from one phase to another seem to coincide for microparticle swelling and drug release. Thus also microparticle swelling might contribute to a significant extent to the control of drug release
Bouffard, Marie-Claude. "Excipients à base de protéines de maïs pour la libération contrôlée de principes actifs alimentaires." Thesis, Université Laval, 2007. http://www.theses.ulaval.ca/2007/24320/24320.pdf.
Boucard, Joanna. "Nanomatériaux magnéto-fluorescents pour la bio-imagerie multimodale et la libération contrôlée de principes actifs." Thesis, Nantes, 2018. http://www.theses.fr/2018NANT4051/document.
These PhD studies consist in the design and characterizations of theranostic nano-tools to meet two requirements. The first one is cell-targeted diagnostics (cancer and muscle cells, bacteria, macrophages) using nanomaterials detectable by fluorescence microscopy and MRI. The second aims at controlling the release of drugs, including anticancerous ones, encapsulated in nanomaterials. The nanometric size of these objects enables enhanced accumulation in tumor tissue (cells), thereby decreasing toxicity side-effects. These objects are supramolecular nanoassemblies composed of a fluorescent solvatochrom organic core coated by a shell of magnetic iron oxide nanoparticles. The emissive core, named FON for fluorescent organic nanoparticle, shows a bright redshifted emission signal compatible with the first biological tissue transparency window. FONs exhibit no cytotoxicity and little photobleaching. The ability of FONs to disassemble once internalized in cellulo and their hydrophobicity enable hydrophobic drugs vectorization. In this way, in cellulo drug delivery can be followed-up by fluorescence microscopy. Drug delivery can be controlled with magnetic hyperthermia thanks to the heating properties due to an alternative magnetic field applied to magnetic nanoparticles. Furthermore, magnetic nanoparticles allow tumor evolution to be monitored in vivo using MRI. All these combined properties pave the way toward theranostic potentialities where personalized nanomedicine is highly requested
Carvajal-Millan, Elizabeth. "Étude de gels d'arabinoxylanes de blé : relations structure, propriétés rhéologiques et libération contrôlée de protéines." École nationale supérieure agronomique (Montpellier), 2004. http://www.theses.fr/2004ENSA0015.
Feruloylated arabinoxylans (AX) extracted from wheat form chemical hydrogels by enzymatic cross-linking of ferulic acid. Gel formation and stability have been followed by rheology and quantification of dimers of ferulic acid (di-FA) as covalent cross-link structures. A trimer. Of ferulic acid (triFA) (4-0-8', 5'-5") newly identified was also taken into consideration. The structural characteristics of gels (molar weight of polymer chain between two adjacent cross-links, cross-link density, mesh size) weredetermined from equilibrium swelling measurements. The relative importance of covalent cross-links (like di-FA) and physical interactions (like hydrogen bonds, entanglements) on the gel structure has been studied by three approaches: a) decrease on the covalent cross-link content in the gels (gelation of partially deferuloylated AX at constant gel AX concentration; b) modification of the covalent cross-link and physical interactions content in the gel (gels at different AX concentrations, AX with the same ferulic acid content) and c) decrease of physical interactions in the gels by including increasing amounts of protein without modifying the gel covalent cross-link content. The results obtained by these 3 approaches suggest a simultaneous contribution of covalent cross-links and physical interactions to the AX gel structure. Covalent cross-links appeared however to play a preponderant role. These covalent cross-links were not only represented by the di-FA and tri-FA identified, the contribution of other ferulate structures (like oligomers of ferulic acid) being also possible. The controlled release of proteins from AX gels has been studied and related to the gel structural characteristics. The proteins have been loaded in AX gels either by diffusion or by gelation of protein-AX solutions. The second method allows the loading of higher amounts of proteins. A better knowledge of the gel structure-function relation would allow the control et macromolecules retention, making AX h dro els a new system for the controlled release of macromolecules
Ben, Azzouz Seifeddine. "Libération contrôlée d'un neuroleptique par voie orale en utilisant des capsules hybrides PLGA-PEG / Alginate/." Thesis, Sorbonne Paris Cité, 2017. http://www.theses.fr/2017USPCC116.
Currently therapeutic treatments for schizophrenia, intravenously or orally, are only partially effective and generally associated with extrapyramidal effects often dangerous and very troublesome for patients. In order, to increase the treatment efficiency by neutralizing any side effects the aim of this work was to design composite capsules (PLGA-PEG / alginate) intended to be administered by way oral and able to release locally, in a specific and controlled way, the neuroleptic “haloperidol” in the brain. The optimization of the protocol of synthesis allowed to obtain in a reproducible way of the nanocapsules of monodisperse and not very aggregate porous PLGA, having an average hydrodynamic diameter lower than 80 Nm and a good stability in aqueous solution. Once functionalized with Poly (ethylene glycol) diamine, in vitro studies showed the low toxicity of these furtive nanoparticles as well as their ability to encapsulate a satisfactory amount of haloperidol and release this active principle over a period of one month with a low burst effect. The incorporation of the PEGylated nanoparticles in matrices prepared with a high concentration of alginate and 100% CaCl2 made it possible to obtain nanocomposite beads having a better stability at the exit from the simulated gastric medium and persist approximately 30 minutes in simulated intestinal medium. Finally, preliminary in vivo studies on adult mice using injected nanoparticles and ingested nanocomposite balls showed the effectiveness of these systems to deliver haloperidol in the brain
Bouledjouidja, Abir. "Imprégnation supercritique pour l'élaboration de systèmes à libération prolongée." Thesis, Aix-Marseille, 2016. http://www.theses.fr/2016AIXM4303/document.
Supercritical impregnation is an attractive “clean” alternative to conventional impregnation processes using generally liquid organic solvents. Among other applications, the impregnation process can be used for the development of controlled drug delivery systems applied to the pharmaceutical and medical fields. This work focuses on the preparation of controlled drug delivery systems using supercritical impregnation of drugs in two kinds of impregnation supports: polymeric matrices (intraocular lenses) and porous supports (mesoporous silica). Firstly, the supercritical impregnation of polymeric intraocular lenses (IOLs), used in cataract surgery, by an anti-inflammatory drug (Dexamethasone 21-phosphate disodium: DXP) and an antibiotic (Ciprofloxacin: CIP), is studied. More particularly, two polymeric IOLs were tested: rigid intraocular lenses made from derivative of PMMA and foldable intraocular lenses made from derivative of P-HEMA. Supercritical impregnations were carried out in a batch mode and the impregnation yields were determined through drug release kinetics studies in a solution simulating the aqueous humor. The influence of operating conditions on impregnation was studied by performing preliminary impregnation experiments followed by experimental designs. The second part of this work deals with the loading of a poorly water-soluble drug (Fenofibrate) in a mesoporous silica for improving drug dissolution kinetics. Supercritical impregnations were carried out with pure CO2 at different pressures (100 to 200 bar) and depressurization rates (rapid and slow)
Bou, Haidar Naila. "Développement d’un pansement à libération contrôlée d’une protéine spécifique anti-biofilm bactérien. Application aux plaies chroniques." Thesis, Normandie, 2019. http://www.theses.fr/2019NORMR087.
Bacterial biofilms are a major obstacle to the wound healing process. In addition, they are responsible for the emergence of resistance and tolerance to antibiotics. Hence, the development of controlled drug delivery systems targeting the bacterial biofilm appears as an urgent and essential alternative therapeutic approach for the effective management of chronic wound. In this work, we developed wound dressings in which a protein, dispersin B (DB), is released capable of selectively targeting the biofilm matrix, creating a deleterious microenvironment for the bacterial biofilm. To this end, we were interested in asymmetric membranes (AMs) from biodegradable polyesters such as the poly(3-hydroxybutyrate-co-4-hydroxybutyrate), the poly (butylene succinate-co-butylene adipate) (PBSA) and the polylactic acid. By the incorporation of hydrophilic porogen agents (PA), we were able to obtain AMs with a high level of porosity, exhibiting a porous interconnected network and oxygen and water vapor permeability. Using bovine serum albumin as a model protein, we demonstrated that protein loading and release from the PBSA AMs were affected by the membrane structure and the presence of residual PA. In vitro studies showed highest antibiofilm efficiency both in inhibition and dispersion (up to 80%). Normalized in vitro cytotoxicity standard assays revealed that unloaded and DB-loaded PBSA membranes met cytocompatibility criteria required for wound dressing applications
Huynh, Thi Diem Uyen. "Structuration de matrices à base de pectine : formulation, caractérisation, fonctionnalités et libération contrôlée lors de l'encapsulation." Thesis, Dijon, 2016. http://www.theses.fr/2016DIJOS019/document.
In this thesis, we studied the interactions between an anionic polysaccharide (pectin) and monovalent cation (Na+) and divalent cations (Ca2+, Zn2+, Ba2+, Mg2+) in dilute regime (c < c*) and concentrate regime (c ≈ c *). Thus, a low methoxy pectin (LMP) was studied in comparison with a polygalacturonic acid (PGA). The affinity to bind calcium ions for these polysaccharides decreases as the NaCl concentration increases. This binding affinity was higher for Ca-polyGal than for Ca-LMP due to the low rigidity of chains observed in the polyGal. The interactions between four divalent cations (Ca2+, Zn2+, Ba2+, Mg2+) and the two biopolymers (polyGal and LMP) in the dilute regime were studied in order to obtain information about the network structure, the mode of association and the binding energy. Therefore, we propose a mechanism of the binding which consists of two steps: i) formation of monocomplexations and point-like cross-links ii) formation of dimers. The threshold molar ratio (R* = [M2+]/[Gal]), between these two steps depends on the number and the stability of the point-like cross-links between polyGal chains and the cation. Mg2+ interacts so strongly with water that is remains weakly bound to polyGal (polycondensation) by sharing water molecules from its first coordination shell with the carboxylate groups of polyGal. Molecular dynamic simulations of galacturonate chains in explicit water showed that the « egg-box » model is more adapted for zinc cations than for calcium and barium. When the concentration of the polyGal is close to the overlap concentration (c*), the addition of divalent cations allows to obtain gels for only three cations (Ca2+, Zn2+, Ba2+). The viscoelastic properties of these gels and the gelation kinetics were studied. In the case of gel formation, the first step (formation of monocomplexations and point-like cross-links) is accompanied by an increase in the gel thickness; while the second step (formation of dimers) leads to a densification of the gel. We found that the diffusion coefficient of the gel front increased according the following order: Ba2+ > Ca2+ > Zn2+ > Mg2+; this may be related to the affinity between the water molecules from the coordination sphere and the cation. Indeed, the affinity of the cation for water molecules increases in the reverse order: Ba2+ < Ca2+ < Zn2+ < Mg2+. Finally, we have used the three polysaccharides (PGA, LMP and ALMP - amidated low methoxyl pectin) in association with calcium ions to produce microparticles containing rutin to target drug release in the intestine. We have linked the rutin release kinetics to the network structure established in the gelation step. ALMP microparticles had higher ability to uptake water and thus higher drug release rate than two others microparticles (Ca-LMP and Ca-PGA). The Ca-ALMP gel was more flexible and had the lower viscoelastic modulus than Ca-PGA and Ca-LMP gels. We attributed this to the random distribution of ester and/or amide groups in ALMP, which hinders the formation of dimers: the hydrogen bonds between the amine groups and carboxylate groups are responsible for the flexibility of the network formed
Chebli, Chafic. "Modification de polysaccharides naturels pour l'obtention de nouveaux excipients pharmaceutiques, liants, délitants et agents de libération contrôlée." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/NQ60588.pdf.
Giacalone, Giovanna. "Implant chargé en nanoparticules pour la libération contrôlée et le ciblage lymphatique de nucléotides et d’analogues nucléotidiques." Thesis, Paris 11, 2014. http://www.theses.fr/2014PA114845.
Natural nucleotides and nucleotide analogs display important pharmacological activities: for example the nucleotide adenosine triphosphate (ATP) could be an interesting molecule for the treatment of ischemia or atherosclerotic plaques. The clinical use of these molecules is however limited due to the presence of a triphosphate group, which is prone to hydrolysis in vivo, and responsible for the high hydrophilicity of the molecules, thereby strongly limiting their uptake by targeted cells and access to their intracellular pharmacological targets. To overcome these limitations and enable the administration of nucleotides and nucleotide analogs, the use of drug delivery systems such as nanoparticles may enable the protection and the targeted delivery of these drugs. Nanoparticles designed for intravenous injections are however not always convenient, e.g. in the case of chronic diseases. Therefore, a subcutaneous implant with sustained release features might represent a valid alternative, which is less invasive and can reach lymphatic tissues (important targets of many therapies). The first chapter of this thesis presents the formulation of nanoparticles to encapsulate ATP as well as zidovudine triphosphate (AZT-TP), thanks to the presence of chitosan (CS). These nanoparticles are formed through ionic interactions between the positive charges of chitosan and the negative charges of the triphosphate groups of ATP or AZT-TP. In this work, nanoparticles are characterized and their cellular delivery of ATP and AZT-TP inside a macrophage cell line is demonstrated. In a second time, the stability of these systems has been improved in order to obtain a better behavior in physiological conditions. This improved stability has been achieved through the complexation of chitosan to iron(III) (CS-Fe). This strategy has been applied to TPP and ATP nanoparticles. These nanoparticles have been tested on two macrophages cell lines showing an improved internalization compared to the previous ones. Finally, CS-Fe/ATP nanoparticles have been dispersed in a PLGA solution in order to develop an in situ forming implant. Once in contact with physiological fluids, the suspension turns into a solid depot. In vitro release studies show the ability of the systems to retain nanoparticles inside the matrix and to gradually release them over 5 days. After subcutaneous administration to mice, PLGA implants containing nanoparticles were able to retain ATP at the injection site for up to 50 hours, as compared to few hours of free ATP or free nanoparticles, showing therefore their relevance as sustained release systems of nucleotides
Grinda, Marion. "Etude de systèmes moléculaires programmés pour la libération sélective d'agents anticancéreux." Poitiers, 2010. http://www.theses.fr/2010POIT2346.
The major problem with conventional cancer chemotherapy is the low selectivity of cytotoxic agents against tumors, causing severe side effects and pleiotropic resistance. To overcome these drawbacks, prodrugs have been developed to be selectively activated at the tumor site by b-glucuronidase during an ADEPT (Antibody Directed Enzyme Prodrug Therapy) or a PMT (Prodrug Mono Therapy) protocol. Within this framework, the glucuronylated prodrug of doxorubicin, HMR 1826, has demonstrated superior efficiency during the treatment of various human xenografs in mice compared to standard chemotherapy. In the course on this PhD new approaches have been developed to improve the scope of glucuronylated prodrugs. The first part of this work describes the synthesis and biological studies for a glucuronylated prodrug of MS-275. The second part is devoted to the study of a new self-immolative dendritic structure designed to target two cytotoxic molecules, even different, and to release the drugs after a single enzymatic hydrolysis. Biological studies have validated the potential of this approach. This concept has been extended to cyclodextrin dimers, to allow the transport of active agent without covalent bonds. Finally, the last approach of the manuscript is devoted to the study of a system suitable for targeting cells and micro-environment specificities of the tumor
Taki, Sofiane. "Elaboration de systèmes à libération controlée d'un herbicide par voie supercritique." Aix-Marseille 3, 2001. http://www.theses.fr/2001AIX30028.
The search for high profitability in agriculture implies to have in hand pesticides more and more active with optimal persistence. A reduction of the treatment frequency comes environmentally and economically interesting in order to reduce the required quantity of active substance and the cost of labour. In this context, controlled release systems seem to be an interesting solution. The purpose here is to entrap a weedkiller (diuron) in a biodegradable polymer (L̂-ilÂJ. The techniques using the supercritical fluids in particular the SAS process offer new ways for the generation ofnano or microparticles of controlled size. This process uses the supercritical carbon dioxide as anti-solvent. The powder obtained is dry and free of organic solvent traces. Preliminary studies of phase equilibria diagrams for the ternary systems of solutes/ solvents/ anti-solvent were carried out in order to select the best operating conditions of pressure and temperature for the SAS process. The results of the precipitation of the L-PLA showed that depending on the concentration used non aggregate spherical microparticles and fibers were formed. The precipitation of the pure diuron leads to the formation of crystals with an acicular habit. .
Moussa, Iskandar. "Diffusion dans les matrices hydrophiles à base d'amylose réticulé, caractérisation et application à la libération contrôlée de médicaments." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0007/NQ39769.pdf.
Quellec, Patricia. "Nanosphères "furtives" à base de copolymères biodégradables pour la libération contrôlée de principes actifs hydrophobes et de protéines." Vandoeuvre-les-Nancy, INPL, 1997. http://www.theses.fr/1997INPL133N.
Herrera, Martinez Juan Manuel. "Octacyanométallates précurseurs de systèmes moléculaires de dimension contrôlée : synthèse, structure et magnétisme." Paris 6, 2003. http://www.theses.fr/2003PA066155.
Cázares, Cortés Esther Del Carmen. "Synthèse de nanogels biocompatibles et multi-stimulables pour la libération contrôlée d'une molécule modèle par hyperthermie magnétique et photothermie." Thesis, Paris 6, 2017. http://www.theses.fr/2017PA066290/document.
Hybrid nanogels, composed of thermoresponsive polymers and inorganic responsive nanoparticles, such as magnetic nanoparticles (NPMs) and gold nanorods (AuNRs) are highly interesting for biomedical applications. Their polymeric matrix makes them able to uptake and release high quantities of drugs, whereas nanoparticles can generate heat when exposed to an alternating magnetic field (AMF) for NPMs, and to a near-infrared light for AuNRs. This thesis manuscript focuses on the synthesis and the characterization of biocompatible, pH- and thermoresponsive nanogels, based on oligo(ethylene glycol) monomers (OEGMAs), methacrylic acid (MAA) and encapsulating NPMs and/or AuNR for remotely triggered doxorubicin (DOX, anticancer drug) release, by magnetic hyperthermia or phothothermia. Hybrid magnetic, plasmonic and magneto-plasmonic nanogels were synthesized. Theses nanogels have a hydrodynamic diameter between 200 and 500 nm and a volume phase transition temperature (VPTT) from 30 to 54°C. The nanogels’ swelling-deswelling behavior can be induced by several stimuli (temperature, pH, AMF, NIR-L). These results demonstrate that MagNanoGels are excellent nanocarriers for enhancing cellular internalization enhancing DOX cytotoxicity and that DOX release was significantly enhanced upon exposure to AMF in athermic conditions. In addition, PlasMagNanoGels can efficiently generate heat by photothermy for thermotherapy. Therefore, the intrinsic properties of NPMs for magnetic targeting and as contrast agents for Magnetic Resonance Imaging (MRI), make these nanogels ideal candidates for a new therapeutic approach (diagnosis and treatment) against cancer
David, Hélène. "Etude de matrices polymères permettant la libération contrôlée d'agents actifs en agriculture : expérimentation et modélisation des transferts de matière." Saint-Etienne, 1989. http://www.theses.fr/1989STET4004.
Malval, Jean-Pierre. "Systèmes supramoléculaires photoactifs pour la détection et la libération optique de cations." Bordeaux 1, 2002. http://www.theses.fr/2002BOR16009.
Laurent, Morgane. "Utilisation d'une décharge à barrière diélectrique pour développer une matrice polymère plasma dégradable pour des applications vasculaires." Thesis, Université Laval, 2017. http://www.theses.fr/2017TOU30189/document.
Every year, about 1.5 million patients need a vascular replacement due to advanced arteriosclerosis, which causes the internal narrowing of blood vessels. Unfortunately, even today the synthetic materials used to replace small diameter arteries (below 6 mm) remain associated with low patency rate, which demonstrates an evident lack of biocompatibility. One of the main observed complications is arterial neointimal hyperplasia, which is characterized by the blood vessel obstruction due to the tridimensional proliferation of cells on the graft internal wall. Different strategies aiming at limiting this body reaction are currently considered, in particular the use of a drug delivery system locally integrated to the vascular grafts. Concurrently, the rise of plasma technologies enabled to demonstrate the possibility to coat the surface of biomedical devices to improve their interaction with a biological environment. The strategy consists in using the plasma energy and reactivity to polymerize a gaseous precursor. By selecting the appropriate precursor molecular structure and plasma experimental conditions, one can build up a plasma polymer with tailored properties. It is in this context that this thesis consisted in synthesizing, using plasma, a biodegradable polymeric plasma polymer matrix to coat the internal wall of a vascular graft, with the goal to incorporate a drug chosen to limit neointimal hyperplasia. On one hand, this project acted as proof of concept by developing a degradable plasma polymer coating using a planar dielectric barrier discharge. After extensive studies using ethyl lactate as precursor, optimal chemical vapor deposition conditions were elected for their potential in terms of vascular applications. On the other hand, thanks to an extended discharge characterization, a strong correlation was established between the plasma physico-chemistry and the properties of the degradable coatings synthesized. In addition, to broaden possibilities in terms of degradation rate, the influence of a squared pulse power supply on the discharge and the coating was studied. If changing the way to bring the energy had a strong influence on the discharge, no major influence was noticed on the ethyl lactate-based coatings' chemistry and morphology. Finally, a tubular plasma reactor was build up to empower the internal wall of vascular prosthesis to be coated, which enabled to extend this project to the deposition conditions of its final application. Overall, this research project highlighted the potential of plasma processes for the development of degradable plasma polymer matrices, particularly for local drug delivery systems for vascular applications. On a physics perspective, this work emphasized the importance of studying the discharge under actual thin layer deposition conditions
Duhirwe, Gilbert. "Polymères à empreintes moléculaires biodégradables : synthèse de nouveaux monomères fonctionnels et agents réticulants à base de sucres." Thesis, Amiens, 2017. http://www.theses.fr/2017AMIE0008/document.
Molecularly imprinted polymers (MIPs) are synthetic biomimetic materials, capable of recognizing and specifically binding a target molecule in a similar way to the natural receptors (antibodies, enzymes, hormone receptors). Considering their screening ability, their mechanical and chemical stability and their weak production cost compared to conventional biomolecules, these materials are used in separative, bioreceptors, synthesis and catalysis fields. However, the use of these materials in controlled drug delivery for clinical applications is still limited due to their lack of biodegradation and biocompatibility. The main drawback lies in the use of functional monomers and cross-linking agents based on petrochemicals products. In this work, we have studied the use of functional monomers and cross-linking agents based on sugars for the development of biodegradable and biocompatible MIPs. These molecules derived from biomass resources are potentially cleavable by enzymes. Firstly, our study focused on selective modification in order to graft polymerisable functions through ester, amide and triazole groups of derivatives based on di-, tri-, and oligosaccharides. Under enzymatic conditions, we observed and verified the cleavage of glycosidic bonds. We finally began a preliminary study of polymerization with these new molecules. Our first results showed that our compounds allowed obtaining hydrophilic polymers, which are degradable under enzymatic conditions
Colinet, Isabelle. "Poly(ε-caprolactone)-g-alginate: synthèse, caractérisation physico-chimique en solution aqueuse et application à la séquestration et à la libération contrôlée". Rouen, 2007. http://www.theses.fr/2007ROUES070.
The aim of this study is to synthesize a new hydrophobically associating water-soluble polysaccharide, prepared by covalent fixation of an hydrophobic, biodegradable and biocompatible polyester, poly(e-caprolactone) (PCL), side chains onto alginate (an anionic polysaccharide) via ester function. Synthesis takes place in heterogeneous media (o/w emulsion) stabilized by a tensioactive. Amphiphilic copolymers (PCL-g-alginate) with two different molar masses of PCL (530 and 1250 g/mol) were synthesized with molar hydrophobe contents ranged from 3. 5% to 15%. These new amphiphilic compounds exhibit, in aqueous solution, the typical properties of hydrophobically associating water-soluble polyelectrolytes. At high dilution, data suggest the formation of compact conformations, resulting from intramolecular hydrophobic associations. Above a critical polymer concentration, intermolecular hydrophobic interactions take place and enhance dramatically the viscosity of copolymer solutions. In salt media, nature of hydrophobic interactions depends on the length of PCL chains. For MPCL=530 g/mol, intramolecular hydrophobic interactions are predominant for a wide range of concentration and for longest PCL chains (MPCL=1250 g/mol) strong intermolecular hydrophobic interactions form and can lead to the formation of a pseudo-gel. Finally, a new amphiphilic drug delivery system was obtained by ionotropic gelation of PCL-g-alginate with calcium ions. It was demonstrated PCL-g-alginate hydrogels can protect an amphiphilic drug (theophylline) in simulated gastric fluid (pH 1. 2), and slow down its kinetic release in simulated intestinal fluid (pH 6. 8) due to hydrophobic interactions between amphiphilic drug and hydrophobic clusters formed by PCL-g-alginate. Results can be correlated with the physico-chemical properties in salt media and 530-x copolymers present a better drug retention. Kinetics release can also be controlled and strongly slow downed by covering the matrices with a polyelectrolyte membrane based on a cationic polysaccharide, chitosan
Savin, Corina-Lenuta. "Biomatériaux à base de polysaccharides modifiés, micro / nanoparticules et sous forme de film, pour la libération contrôlée de principes actifs." Thesis, Mulhouse, 2018. http://www.theses.fr/2018MULH2379.
The objective of the thesis was to obtain novel gels based on polyglobalide or chitosan for the transport, targeting and controlled release of drugs, in cases of specific skin conditions, as well as certain diseases of the posterior segment of the eye. A new type of polyglobalide-based polymeric gels and of poly(ethylene glycol) with thiol function were prepared by photo-induced thiol-ene addition reaction, in order to carry out an active transport of the drugs. The systems obtained were analyzed structurally and morphologically. The materials obtained have large pore sizes, about 30, 60 and 150 μm for the gels obtained at the initial polymer concentration of 20, 10 and 5%, respectively. This porosity may be important for tissue engineering applications. New type of micro/nanoparticles based on chitosan grafted with poly(ethylene glycol) methacrylate were also synthesized by a double cross-linking inverse emulsion process. The particles with optimal characteristics (in terms of morphology, degree of swelling in water…) were analyzed from the point of view of the encapsulation and release capacity of specific drugs (Bevacizumab, respectively Levofloxacin). These micro/nanoparticles show a high degree of swelling (700 ± 1000%), which explains the high efficiency of loading the drugs. The prepared nanoparticles are hemocompatible and can be administered intraocularly/ intravenously. The results of the in vitro release are encouraging, showing that the amount of levofloxacin released in 120 hours for levofloxacin and 583 hours for bevacizumab is very sensitive to the maximum dose usually given to the patients with ocular infections. The novelty of these systems consists in obtaining a new vector in particle form, that could be administered by injection into the eyeball, either by instillation into the conjunctival sac of the eye. These systems are also able to include, transport and release drugs, which will treat inflammation and neovascularization
Ouriemchi, El Mekki. "Étude in vitro de nouvelles formes pharmaceutiques orales à libération contrôlée : modélisation de leur comportmeent dans le cas in vivo." Saint-Etienne, 1995. http://www.theses.fr/1995STET4013.
Reymann, Anne-Cécile. "Dynamique des réseaux d'actine d'architecture contrôlée." Phd thesis, Université de Grenoble, 2011. http://tel.archives-ouvertes.fr/tel-00686015.