Dissertations / Theses: 'Carbohydrates polymer'

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Yuwen, Jing. "Polymer-Based Photoactive Surface for the Efficient Immobilization of Nanoparticles, Polymers, Graphene and Carbohydrates." PDXScholar, 2011. https://pdxscholar.library.pdx.edu/open_access_etds/413.

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This thesis focuses on developing a new photocoupling surface, base on polyallyamine (PAAm), to increase the efficiency of the photocoupling agent perfluorophenyl azide (PFPA) in the immobilization of nanoparticles, carbohydrates and graphene. Extensive studies have been carried out in our lab on the covalent immobilization of polymers and graphene using PFPA-functionalized surfaces. Here we show that PAAm-based PFPA surface can be used to efficiently immobilize not only graphene and polymers but also nanomaterials and small molecules. This was accomplished by first silanizing silicon wafers with PFPA-silane followed by attaching a thin film of PAAm by UV radiation. Treating the PAAm surface with N-hydroxysuccinimide-derivatized PFPA (PFPA-NHS) yielded the PAAm-PFPA surface. The functionalized surfaces were characterized by ellipsometry (layer thickness), contact angle (surface tension), and ATR-FTIR. The PAAm surface was further characterized by determining the density of amino groups on the surface. The PAAm-PFPA surfaces were subsequently used to covalently immobilize polymers, nanomaterials, carbohydrates and graphene by a simple procedure of coating the molecules or materials on the PAAm-PFPA surface followed by UV irradiation. The resulting surfaces were characterized using ellipsometry, AFM, optical microscopy. The attached carbohydrates were further evaluated using lectins, i.e., carbohydrate-binding proteins.

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Moore, Martin. "New Dipolar Cycloaddition reactions of a Carbohydrate-derived Vinyl Sulfoxide Alkyne Equivalent and a Polymer-supported Alkyne with Azides." Connect to online version at OhioLINK ETD Connect to online version at Digital.Maag, 1998. http://hdl.handle.net/1989/4782.

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Kantchev, Assen B. "Part 1, Oligosaccharide synthesis on a hyperbranched polymer as soluble support ; Part 2, Photoresponsive conformational equilibria of chiral, helically folded dendrons /." The Ohio State University, 2001. http://rave.ohiolink.edu/etdc/view?acc_num=osu1486572165275834.

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Abeylath, Thotaha Wijayahewage Sampath Chrysantha. "Glyconanobiotics : novel carbohydrated nanoparticle polymers." [Tampa, Fla] : University of South Florida, 2007. http://purl.fcla.edu/usf/dc/et/SFE0001948.

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Gaitonde, Vishwanath Venkatesh. "Carbohydrate-Based Synthetic Methodology and Polymer Development." University of Toledo / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1438939333.

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Liu, Xiaohong. "Synthesis and Characterization of Carbohydrate-conjugated Polyesters and Polyurethanes." University of Akron / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=akron1491433530882435.

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7

Mazzoccoli, Jason Paul. "ULTRASONICATION OF POLYSACCHARIDE MATERIALS." Cleveland, Ohio : Case Western Reserve University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=case1262572128.

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Thesis (Doctor of Philosophy)--Case Western Reserve University, 2010
Department of Chemical Engineering Title from PDF (viewed on 2010-05-25) Includes abstract Includes bibliographical references and appendices Available online via the OhioLINK ETD Center

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Taylor, Leeanne R. "Rational design of glycosaminoglycan mimics using N-alkyl-N,N-linked urea oligomer containing polymers." University of Cincinnati / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1406819426.

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Benjamin, Michael. "Synthesis, Characterization, and Determination of Relaxivities for Glycoamido-DTPA Polymers for Use as MRI Contrast Agents." University of Cincinnati / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1154109396.

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10

Pan, Yining. "Immobilized Viologen Polymer for Use in Direct Carbohydrate Fuel Cells." BYU ScholarsArchive, 2013. https://scholarsarchive.byu.edu/etd/3524.

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Glucose and other carbohydrates are some of the most abundant renewable energy sources in the world. The oxidation of carbohydrates in a fuel cell allows their chemical energy to be converted directly into electrical energy. Viologen has been indentified and shows promising ability as an electron-transfer catalyst or mediator for carbohydrate oxidation in an alkaline carbohydrate fuel cell. Building on the previous results, the objective of this work was to develop an immobilization chemistry of viologen onto an electrode and to investigate the catalytic activity for carbohydrate oxidation in direct carbohydrate fuel cells.The immobilization was achieved by electropolymerizing a novel viologen monomer onto an electrode surface. The novel viologen monomer, which functions as a monosubstituted viologen, was synthesized and isolated in-house. Gold-plated nickel wire and graphite disks were used as the substrates for the electropolymerization. SEM, EDAX, XPS and water-contact-angle measurement were used to verify the formation of the coating on the gold and graphite surfaces. The catalytic activity of the immobilized viologen on graphite disk surface was examined using a fuel-cell-like device. The test was operated within the desired pH range for an operating fuel cell; it was found that the immobilized viologen polymer has a low catalytic activity toward oxidizing carbohydrates. In addition, the electrochemical properties of the novel viologen monomer were investigated by the method of cyclic voltammetry, as well as for that of two aminoviologens synthesized in-house. Redox potentials, diffusion coefficients, and heterogeneous electron-transfer rate constants were determined.

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Kampulainen, Atte J. "Interfacial properties of some carbohydrate-based surfactants and polymers." Doctoral thesis, KTH, Chemistry, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3728.

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The aim of this thesis is primarily to investigate theadsorption of surfactants, in particular to the airwaterinterface. The effects of the head-group and the hydrocarbonchain are of special interest. Using thermodynamical models wewere able to predict that the transition from the Henry rangeto the liquid-expanded phase is controlled by the formation ofsmall clusters of surfactants oriented in the plane of thesurface. Hence, the transition from the Henry range can not beof first-order, and additionally the phase formed after theonset of the micelle formation does have a liquid-likecharacter. We refer to this phase as the dilute surfacemicellar range. Interactions between the micelles in the dilutesurface micellar range can be accounted for by excluded areainteractions using the harddisc model. The stability of themicelles can be attributed to the line tension acting on themicelle edge, which stops unlimited growth of the surfacemicelles. With increasing density of surface micelles a newphase is formed, referred to as the granular phase. Thegranular phase exhibits very low compressibilty and an almostconstant area/molecule in an extended surfactant bulkconcentration interval. For three sugar-based surfactantscarrying decyl hydrocarbon tails at room temperature thedefining area/molecule is in the close vicinity of 79 Å². In the granular phase the lines of the surfacemicelles are intact, but distorted probably into a morehexagonal shape to cover the surface. For a sugar-basedsurfactant carrying dodecyl hydrocarbon tail the definingarea/molecule in the granular range was found to be close to 70Å². For one of the decyl surfactants 70 Å²was also observed, indicating the existence of afew seemingly discrete adsorption modes for surfactants in thegranular range. The transition from the granular range to thetrue liquid-expanded phase, defined by a complete coverage ofthe entire surface of fluid hydrocarbon tails, is seemingly afirst-order transition. This is indicated in the surfacetension isotherm by a "knee" with an abrupt change from aconstant surface density (granular phase) to a lower molculararea and an increasing adsorption with increasing surfactantchemical potential (true liquid-expanded phase). In theliquid-expanded phase the role of the hydrocarbon chainrestriction in the surface was investigated by applying thehard-disc model on mixtures of sugar-based decyl surfactants toaccount for the head-group surface fractions obtained byapplying Gibbs surface tension equation to mixtures ofsugar-based surfactants. The behaviour of the head-groups atthe interface was accurately described by a hard-disc model,and hence this resulted in a prediction of the decylhydrocarbon chain configurational pressure as a function ofmolecular area. Applying the deduced configurational pressureon pure surfactants yielded accurate models on the surfacepressure and excess free energy contribution from thehead-groups. Futhermore, the limits of the predictioncapability of the model separation of head-group andhydrocarbon tail phase was tested by means of systemsexhibiting partial interpenetration of the head-group into thehydrocarbon tail phase. For ethylene-oxide-based surfactants aweak interpenetration effect was observed. However, for thethiomaltoside head-group a large effect due to interpenetrationwas encountered. This was deemed to be related to thereorientation of the head-group due to the preferential mixingof the sulphur with the hydrocarbon tail phase. Frommeasurements of surface tension after the cmc the averagemicelle size of n-dodecyl-ß-D-maltopyranoside wasdetermined to be 76 monomers. Surface forces measurements usingcrystalline hydrophobic surfaces in sugar-based surfactantsolution proved that surfactants desorb at low applied loads.Surface forces measurements on adsorbed layers of cationicpolymer containing ß-cyclodextrin (ß-CD-EPN) adsorbedonto mica in solutions of admantanegrafted polyethylene-oxidepolymers (Ad-PEO) were performed to investigate the interactionbetween ß-cyclodextrin and admantane. In the absence ofAd-PEO very low adhesion was observed between the ß-CD-EPNcoated mica surfaces, on addition of Ad-PEO a significantincrease was detected in both layer thickness and adhesion.This was attributed to the interaction between admantane andß-cyclodextrin.

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Ward, Steven Richard. "EPR studies of carbohydrate-derived free radicals and alkene polymerisation." Thesis, University of York, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.310958.

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O'Neill, Ellis. "An exploration of phosphorylases for the synthesis of carbohydrate polymers." Thesis, University of East Anglia, 2013. https://ueaeprints.uea.ac.uk/47480/.

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Phosphorylases are interesting enzymes with regard to both their role in metabolism and their use in the in vitro synthesis of carbohydrates. The disaccharide phosphorylases have attracted attention because of their strict stereo- and regiospecificity and their tractability. The polymerising phosphorylases have received less attention due to heterogeneous product formation, requiring more complex analyses. In this work three polymerising carbohydrate phosphorylases have been studied. The plant α-1,4-glucan phosphorylase PHS2 is closely related to the well characterised mammalian glycogen phosphorylase. We present the first crystal structures of the plant enzyme which reveals a unique surface binding site. PHS2 allowed the production of novel starch like surface, both in two and three dimensions, which show some of the same properties as a native starch granule. This can now be used to study starch-active enzymes on an insoluble glucan surface which is analogous to the native starch granule. The bacterial β-1,4-glucan phosphorylase CDP is involved in degradation of cellulose. In the reverse direction this enzyme allows the rapid synthesis of cellulose polymers in solution and also allows the synthesis of hemicellulose-like materials. The substrate specificity can in part be probed in the crystal structure presented here, which represents the first structure of a polymerising, inverting phosphorylase. Together these data provide the foundation for further work with this enzyme in the synthesis of plant cell wall related glycans. The third enzyme studied was the β-1,3-glucan from the unsequenced alga Euglena gracilis, which was used for the facile enzymatic synthesis of β-glucosyl glycerols. In order to identify the sequence of this enzyme we obtained de novo transcriptome sequencing data from this alga, which has revealed unexpected metabolic diversity. Aside from complex carbohydrate metabolism, there are also many surprising features, including novel enzyme architectures, antioxidants only previously noted in human parasites and complex natural product synthases.

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14

Sizovs, Antons. "Development of Carbohydrate-based Diblock Polymers for Nucleic Acid Delivery." Diss., Virginia Tech, 2012. http://hdl.handle.net/10919/77089.

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The delivery of nucleic acids remains the major obstacle for nucleic acid-based therapies such as gene therapy and gene silencing therapies based on RNA interference. In this dissertation we have developed and studied nucleic acid delivery vehicles based on cationic diblock glycopolymers that contain glucosamine and trehalosamine. Practical procedures were developed to synthesize 2-methacrylamido-2-deoxy glucose and 6-methacrylamido-6-deoxy trehalose starting with commercially available carbohydrates and utilizing trimethylsilyl protecting group chemistry. These monomers were polymerized via reversible addition-fragmentation chain transfer (RAFT) polymerization to yield glycopolymers with the desired lengths and low polydispersity indexes. Glycopolymers were chain-extended with aminoethylmethacrylamide to produce cationic diblock copolymers. The ability of cationic diblock copolymers to bind nucleic acids was demonstrated with gel electrophoresis and heparin exclusion assays. Complexes of the synthesized polymers with nucleic acids were studied with dynamic light scattering to reveal nanoparticles of 100-250 nm that were stable in the presence of serum proteins. Quartz crystal microbalance experiments showed that serum proteins adsorb on polytrehalose coated gold surfaces and it was suggested that these interactions may help mask the polytrehalose coated nanoparticles from potential actions of the immune system. Polytrehalose was also shown to suppress water crystallization similarly to trehalose by lowering the energies associated with the water/ice phase transition. The property was utilized to freeze-dry siRNA containing polyplexes which could be re-dissolved in water after lyophilization to yield nanoparticles. The polyplexes formulated with cationic diblock copolymers were shown to efficiently enter cervical cancer cells (HeLa cell line) and glioblastoma cells (U-87 cell line) and to deliver their nucleic acid cargo. Polyglucose-containing polymers were efficient mediators of exogenous gene expression in HeLa cells, and polytrehalose- containing polymers were effective in promoting the target gene down-regulation via RNA interference by delivered siRNA.
Ph. D.

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15

Ahn, Jiyoung Ph D. Massachusetts Institute of Technology. "Design and synthesis of polymers for Corona Phase Molecular Recognition (CoPhMoRe) of carbohydrates." Thesis, Massachusetts Institute of Technology, 2017. https://hdl.handle.net/1721.1/122841.

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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Chemical Engineering, 2017
Cataloged from PDF version of thesis. Page 158 blank.
Includes bibliographical references (pages 133-157).
The molecular recognition of carbohydrates is difficult to realize synthetically due t& their relatively low affinity for a wide range of substrates, yet this recognition is the underpinning of human immunity, cell signaling, and glycobiology. For the past decade, significant effort has been made in this field to create new technologies to profile glycans and carbohydrates. Corona Phase Molecular Recognition (CoPhMoRe), the concept introduced from Strano group, generates a nanoparticle coupled polymer phase capable of recognizing a specific molecule with high affinity and selectivity. CoPhMoRe has been successfully demonstrated using polymer wrapped single walled carbon nanotubes, resulting in molecular recognition complexes, to date, for dopamine, estradiol, riboflavin, L-thyroxine, and the protein fibrinogen, utilizing combinatorial library screening. As an alternative to this empirical, library screening, we first solve the mathematical formulation that we introduce as the CoPhMoRe inverse problem to provide a theoretical basis for understanding certain types of CoPhMoRe recognition. In addition, we demonstrate that a polymer or surfactant corona phase surrounding a single walled carbon nanotube can substantially modify the selectivity of various pre-adsorbed phenyl-boronic acids (PBA) for mono-, di- and polysaccharides. Based on these findings, a simple and robust RAFT polymerization process is employed to produce novel and distinct classes of water-soluble PBA-based polymers. These polymers in SWNT corona phases demonstrate enhanced selectivity towards specific sugar alcohols, which differ only in the orientation of the hydroxyl groups. By changing the polymer backbone structure, highly selective D-Arabinose sensor was developed and used to differentiate D-Arabinose from L-Arabinose for the first time. Finally we developed a glucose sensor that can measure glucose concentration instantaneously by detecting changes in local refractive index.
by Jiyoung Ahn.
Ph. D.
Ph.D. Massachusetts Institute of Technology, Department of Chemical Engineering

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16

Morgan, Joel Ryan. "The synthesis of glycodendrimers and their applications in carbohydrate-protein interactions and catalysis." Diss., Montana State University, 2006. http://etd.lib.montana.edu/etd/2006/morgan/MorganJ0806.pdf.

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17

Basu, Sarkar Arindam Kochak Gregory Michael. "Carbohydrate nanoparticles a novel drug delivery platform for the systemic route /." Auburn, Ala., 2006. http://repo.lib.auburn.edu/2006%20Summer/Dissertations/BASU_SARKAR_26.pdf.

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Nijjar, Rajdeep Kaur. "Polymer-supported synthesis of oximino disaccharides and preliminary investigations into Beckmann rearrangements of carbohydrate oximes." Thesis, University of Reading, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.445743.

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Bunnfors, Kalle. "Synthesis and electrochemical characterisation of processable polypyrrole boronic acid derivatives for carbohydrate binding." Thesis, Linköpings universitet, Biosensorer och bioelektronik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-121652.

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Conducting polymers have been widely explored for many different purposes including sensing. In thisthesis the conducive properties of pyrrole and the carbohydrate binding properties of boronic acid iscombined to make a reagent-free detector for carbohydrates. The polymer is manufactured in form ofparticles in the μm scale to create a porous film which has a high surface to volume ratio.The material was characterised and the binding properties were evaluated for galactose and glucose.Proof of binding was found via both electrochemical methods and QCM-D. A correlation between R2 value and concentration of substrate was found which enables measurement of concentration of carbohydratesin unknown samples.

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Ouhab, Djamila. "Auto-assemblage dirigé de copolymères à blocs de forte incompatibilité comprenant un bloc carbohydrate pour des applications de nano-Lithographie." Thesis, Université Grenoble Alpes (ComUE), 2016. http://www.theses.fr/2016GREAV006/document.

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En combinant l’expertise du Cermav dans la conception de films minces de très haute résolution obtenus par auto-assemblage de glycopolymères biosourcés et le savoir-faire du LETI sur les procédés de lithographie innovante, l’objectif de ce projet de thèse est d’évaluer ces nouveaux copolymères biosourcés -associant des oligosaccharides- comme solution alternative pour la nano lithographie de demain. En effet, ces dernières années l’équipe de « Physico-chimie des glycopolymères » du Cermav dirigée par R. Borsali a développé une nouvelle classe de glycopolymères (type PS-Maltoheptaose, PCL-Maltoheptaose, Xyloglycan-PSSI) pouvant s’auto-organisér avec une résolution de 5nm, dépassant ainsi largement la résolution atteinte aujourd’hui par les seuls copolymères à blocs issus du pétrole type PS-PMMA (20nm). En parallèle, durant les deux dernières années, le Cea/Leti a validé le potentiel des procédés basés sur l’auto assemblage des copolymères à bloc type PS-b-PMMA (résolution 20nm) comme solution alternative aux techniques de lithographie actuelles. Ces résultats positionnent le Cea/Leti dans l’état de l’art international et constituent une bonne base pour intégrer, dans le domaine de la nano-electronique, de nouveau systèmes à plus forte résolution (<10nm), tels que ceux développés par le Cermav. Le travail de thèse proposé se déroulera en trois temps : – Dans un premier temps le candidat adressera la synthèse et la caractérisation de nouveaux copolymères à blocks hybrides associant des oligosaccharides. – Ensuite il va d’intéressé à l’élaboration de glycofilms nano-organisés ainsi que à l’identification des facteurs importants jouant sur la nano-organisation. – Et finalement le contrôle de l’organisation à l’échelle nanométrique par grapho-épitaxie pour des applications lithographiques sera adressé. Deux applications seront visées : le contact et la ligne (phases cylindriques et lamellaires). La compatibilité du procès avec les contraintes de la micro-électronique sera également détaillée
Combining the Cermav expertise in the thin films design with very high resolution obtained by self-assembly of glycopolymers biobased and the know-how of LETI on innovative lithography processes, the objective of this thesis is to evaluate these new bio-based copolymers, combining-oligosaccharides as an alternative for nano lithography tomorrow. Indeed, in recent years the team of "Physical Chemistry of glycopolymers" of Cermav directed by R. Borsali has developed a new class of glycopolymers (PS-maltoheptaose, PCL-maltoheptaose, Xyloglycan-PSSI) can self-organize with a resolution of 5 nm, far surpassing the resolution reached today only by block copolymers from Oil PS-PMMA (20 nm). In parallel, during the last two years, Cea / Leti has validated the potential methods based on self-assembly of block copolymers PS-b-PMMA (20 nm resolution) as an alternative to the current lithography techniques. These results position the Cea / Leti in the international state of the art and provide a good basis for integration in the field of nano-electronics, new systems with higher resolution (<10 nm) as those developed by the Cermav. The proposed thesis work will take place in three stages: - First time candidate address the synthesis and characterization of new copolymers blocks combining hybrid oligosaccharides. - Then he's going to be interested in the development of nano-glycofilms organized as well as to identify important factors playing on the nano-organization. - And finally the control of the organization at the nanoscale by grapho-epitaxy for lithographic applications will be addressed. Two applications are described: the contact line (cylindrical and lamellar phases). Compatibility constraints trial microelectronics will also be detailed

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21

Söyler, Zafer [Verfasser], and M. A. R. [Akademischer Betreuer] Meier. "Sustainable and efficient functionalization methods for carbohydrate polymers / Zafer Söyler ; Betreuer: M. A. R. Meier." Karlsruhe : KIT-Bibliothek, 2018. http://d-nb.info/1167308999/34.

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22

LEE, CHEN-CHANG. "Design, Synthesis, and Structure-Bioactivity Characterization of Novel Carbohydrate-Based Polymers as Nucleic Acid Delivery Vectors." University of Cincinnati / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1211919868.

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Vartak, Abhishek R. "Synthesis and Evaluation of Multi-component Immuno-therapeutics Containing Peptide and Carbohydrate-based Antigens." University of Toledo / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1560356357892348.

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24

Norell, Isabella. "Phaeodactylum tricornutum – Compositional Analysis, Carbohydrate-Active Enzymes and Potential Applications of Residual Algal Biomass from Omega 3 Production." Thesis, KTH, Industriell bioteknologi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-292409.

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Microalgae are gaining more attention for several reasons such as being potential producers of sustainable fuel, for use as health supplements and in skincare. Simris Alg is a Swedish company that produces Omega 3 supplements from a primary producer of these fatty acids - the algal diatom Phaeodactylum tricornutum, which is a sustainable alternative to Omega 3 derived from fish. Omega 3 fatty acids constitute a small fraction of the total algal biomass, and to increase profitability and utilize all of the biomass, the purpose of this thesis project is to present potential applications for the residual material that is left after oil extraction. A general composition study was made of Simris Alg algal residue material, and results are compared to those found in previous studies of P. tricornutum biomass. An optimization of the fractionation is needed to separate the storage carbohydrate chrysolaminarin and cell wall component glucuronomannan, followed by analysis for confirmation. Also, it would be interesting to separate chitin, if there is any, since despite the presence of chitin synthases, it is unclear whether the diatom actually produces chitin. When gathering information, no actual experimental characterization of carbohydrate active enzymes involved in synthesis of the main carbohydrates investigated were found. Such information would be useful to increase production of the carbohydrate of interest, if valuable applications are found. Potential applications of various cell components, such as carbohydrates, in skincare would be interesting to investigate, as well as optimizing fucoxanthin extraction for use as an additional high value product next to Omega 3.

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Becker, Stefan [Verfasser], Jan-Hendrik [Akademischer Betreuer] Hehemann, Jan-Hendrik [Gutachter] Hehemann, and Carol [Gutachter] Arnosti. "Biocatalytic quantification of laminarin : a major carbohydrate polymer in the ocean / Stefan Becker ; Gutachter: Jan-Hendrik Hehemann, Carol Arnosti ; Betreuer: Jan-Hendrik Hehemann." Bremen : Staats- und Universitätsbibliothek Bremen, 2018. http://d-nb.info/1164151835/34.

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BATISTA, JORGE G. dos S. "Desenvolvimento de matrizes poliméricas biodegradáveis à base de quitosana e possíveis blendas como sistemas de liberação controlada de fármacos." reponame:Repositório Institucional do IPEN, 2015. http://repositorio.ipen.br:8080/xmlui/handle/123456789/26076.

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Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2016-04-08T12:18:22Z No. of bitstreams: 0
Made available in DSpace on 2016-04-08T12:18:23Z (GMT). No. of bitstreams: 0
Dissertação (Mestrado em Tecnologia Nuclear)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

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Wallner, Fredrik. "Glycoconjugates : Solid-phase synthesis and biological applications." Doctoral thesis, Umeå : Univ, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-630.

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Otsuka, Yoko. "Films minces nanostructurés de domaines sub-10 nm à partir de copolymères biosourcés pour des applications dans le photovoltaïque organique." Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAV024/document.

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La structuration nanométrique par l'auto-assemblage des copolymères à blocs est l'une des stratégies « bottom-up » prometteuses pour contrôler la morphologie de la couche active de cellules photovoltaïques organiques. Dans cette thèse, une nouvelle classe de copolymère constitué d’un bloc semi-conducteur π-conjugué poly(3-hexylthiophène) (P3HT) regioregulier et d’un bloc oligosaccharidique a été synthétisée et a montré une auto-organisation en nanostructures périodiques de domaine inférieure à 10 nm. Deux systèmes de copolymères à blocs ont été synthétisés, le P3HT-bloc-maltoheptaose peracétylé (P3HT-b-AcMal7) et le P3HT-bloc-maltoheptaose (P3HT-b-Mal7), via une réaction de chimie "clic" entre les segments oligosaccharidiques et P3HT fonctionnalisés en extrémité. Une étude exhaustive sur leur comportement d'auto-assemblage par des analyses AFM, TEM et de diffusion des rayons X a révélé que le copolymère à bloc P3HT-b-AcMal7 montre une propension à s'auto-assembler par recuit thermique en structures lamellaires avec une résolution inférieure à 10 nm, c’est-à-dire la morphologie et la taille idéale pour la couche active d’une cellule photovoltaïque organique. De plus, ce système présente l’une des plus petites tailles de domaines réalisées par l'auto-assemblage de copolymères à blocs à base de P3HT. Un réseau lamellaire composé uniquement du P3HT a été obtenu par gravure chimique sélective du bloc sacrificiel AcMal7 à partir d'un film nano-organisé de P3HT-b-AcMal7 et ceci sans affecter la structure lamellaire initiale. Les domaines vides du AcMal7 gravé pourront être remplis par un composé accepteur d'électrons tel que le [6,6]-phényl-C61-butanoate de méthyle (PCBM) pour l’application photovoltaïque comme perspective de cette thèse. Les résultats et les connaissances acquises dans cette étude devraient permettre d'augmenter les performances des prochaines générations de cellules photovoltaïques organiques
Nanoscale patterning through self-assembly of block copolymers is one of the promising bottom-up strategies for controlling active layer morphology in organic photovoltaics. In this thesis, a new class of carbohydrate-based semiconducting block copolymers consisting of π-conjugated regioregular poly(3-hexylthiophene) (P3HT) and oligosaccharides were synthesized and self-organized into sub-10 nm scale periodic nanostructures. Two different diblock copolymers, i.e. P3HT-block-peracetylated maltoheptaose (P3HT-b-AcMal7) and P3HT-block-maltoheptaose (P3HT-b-Mal7) were synthesized via "click" reaction between end-functionalized oligosaccharide and P3HT moieties. A comprehensive investigation of their self-assembly behavior by AFM, TEM, and X-ray scattering analyses revealed that the P3HT-b-AcMal7 diblock copolymer has the ability to self-assemble into sub-10 nm scale lamellar structure, which is the ideal morphology of the active layer in organic photovoltaics and one of the smallest domain sizes achieved by self-assembly of P3HT-based block copolymers, via thermal annealing. Nano-patterned film made of P3HT was attained by selective chemical etching of AcMal7 block from microphase-separated P3HT-b-AcMal7 template without affecting the original lamellar structure. The resultant void where the etched-out AcMal7 block existed will be filled with electron acceptor compounds such as [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) for photovoltaic application as a perspective of this thesis. The results and knowledge obtained in this study are expected to provide further advances and innovation in organic photovoltaics

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29

Majumdar, Debatosh. "Synthesis of biologically important carbohydrates and glycoconjugates by solution phase and polymer supported approaches." 2004. http://purl.galileo.usg.edu/uga%5Fetd/majumdar%5Fdebatosh%5F200408%5Fphd.

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Thesis (Ph. D.)--University of Georgia, 2004.
Directed by Geert-Jan Boons. Includes an article published in Organic letters, and an article submitted to Journal of organic chemistry. Includes bibliographical references.

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30

(6369032), Jingfan Chen. "Exploring the interaction between functional carbohydrate polymers and small-molecule active compounds." Thesis, 2021.

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Naturally occurring carbohydrates polymers and their functional derivatives play important roles in the research and technology development in the food, nutrition, and pharmaceutical areas. A major property of these polymeric materials is to associate, enable, enhance, and/or deliver small-molecule active compound such as phytochemicals, nutraceuticals, and active pharmaceutical ingredients (APIs). The goal of this project was to synthesize and characterize phytoglycogen-based materials and study their structure-function relationships in association with selected small-molecule active compounds, including resveratrol, a food-related poorly water-soluble phenolic compound, griseofulvin, an insoluble API, and CCVJ (9-(2-carboxy-2-cyanovinyl) julolidine) a molecular rotor used as a structural probe of polymeric materials.

In this study, phytoglycogen (PG) was derivatives to phytoglycogen octenyl succinate (PG-OS), hydroxypropyl phytoglycogen (HPP), and octenylsuccinate hydroxypropyl phytoglycogen (OHPP). PG, HPP, and OHPP were evaluated for their efficacy in improving the solubility and Caco-2 permeation of resveratrol and griseofulvin, and using CCVJ, PG-OS was evaluated on its performance at oil-water interface in comparison with OSA-starch, acacia gum, and sodium caseinate. The results showed that: 1) PG, HPP, and OHPP substantially improved the soluble amount and Caco-2 monolayer permeation of resveratrol and griseofulvin, and anti-fungal efficacy of griseofulvin in the aqueous system were significantly enhanced; suggesting that the active ingredients were effective solubilized and released to become bioavailable, 2) among all PG-based biopolymers, OHPP showed superior performance in solubilizing resveratrol and griseofulvin, and 3) in the oil-water two-layer model system, PG-OS, OSA-starch, acacia gum, and sodium caseinate all affected the transferring of CCVJ from oil to aqueous phase, and the effect was monitored and interpreted by the emission spectra of molecular rotor; in the emulsion system, the emission peak wavelength of CCVJ was correlated with the amount of biopolymer adsorbed at the interface of emulsion droplets, and the molecular rotor-based method can be used to characterize the interfacial adsorption of biopolymer at the interface in oil-in-water emulsion.

This study provides information on the interactions between phytoglycogen-based biopolymers and poorly water-soluble active ingredients, and may potentially supports the study of new functional ingredients interaction with phytoglycogen-based biopolymers in aqueous system. Furthermore, this work allowed us to advance the use of molecular rotor as new analytical tool to study the physicochemical properties of biopolymer.

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LIU, SI-XIAN, and 劉思嫺. "Preparation of Carbohydrate Polymers Containing Three Different Tumor-Associated Carbohydrate Antigens." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/2sgct7.

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碩士
輔仁大學
化學系
107
Preparation of styrene-type glycoconjugates monomers, containing tumor-associated carbohydrate antigens (TACAs), such as Tn (Ser- / Thr- type), TF and sTn were developed. Polymerization of these TACAs monomers with polystyrene framework by NMP (Nitroxide-mediated radical polymerization) were also studied. Tn antigens were synthesized by the glycosylation reactions of D-galactose derivative, as glycol donor and L-serine or L-threonine derivatives as glycol acceptors. The first glycosylation reaction was proceeded to get the glycoproteins building blocks. The α-anomer was separated, and then attached to styrene through a spacer of diethylene glycol amine. The Tn glycoconjugate monomers were polymerized successfully to afford Tn glycoconjugate glycopolymers. To prepare others antigens, several functional groups were protected. Attachments of the second carbohydrate moieties, such as D-galatose and sialic acid, were constructed by the second glycosylation reactions. These two antigens were synthesized by the same methods used in the synthesis of Tn monomers, and eventually afforded three different types of glycoconjugates monomers. Controlled living radical polymerization (CLRP) of these three Tn glycoconjugate monomers were studied to produce the random and block co-polymers. Resulting glycopolymers were analyzed by NMR and ATR-IR to confirm TACAs presented on the polystyrene backbone.

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Crucho, Carina Isabel Correia. "Synthesis of Polymeric Nanoparticles for biomedical delivery applications." Doctoral thesis, 2015. http://hdl.handle.net/10362/14994.

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Polymeric nanoparticles (PNPs) have attracted considerable interest over the last few years due to their unique properties and behaviors provided by their small size. Such materials could be used in a wide range of applications such as diagnostics and drug delivery. Advantages of PNPs include controlled release, protection of drug molecules and its specific targeting, with concomitant increasing of the therapeutic index. In this work, novel sucrose and cholic acid based PNPs were prepared from different polymers, namely polyethylene glycol (PEG), poly(D,L-lactic-co-glycolic acid) (PLGA) and PLGA-co-PEG copolymer. In these PNP carriers, cholic acid will act as a drug incorporation site and the carbohydrate as targeting moiety. The uptake of nanoparticles into cells usually involves endocytotic processes, which depend primarily on their size and surface characteristics. These properties can be tuned by the nanoparticle preparation method. Therefore, the nanoprecipitation and the emulsion-solvent evaporation method were applied to prepare the PNPs. The influence of various parameters, such as concentration of the starting solution, evaporation method and solvent properties on the nanoparticle size, size distribution and morphology were studied. The PNPs were characterized by using atomic force microscopy (AFM), scanning electron microscopy (SEM) and dynamic light scattering (DLS) to assess their size distribution and morphology. The PNPs obtained by nanoprecipitation ranged in size between 90 nm and 130 nm with a very low polydispersity index (PDI < 0.3). On the other hand, the PNPs produced by the emulsion-solvent evaporation method revealed particle sizes around 300 nm with a high PDI value. More detailed information was found in AFM and SEM images, which demonstrated that all these PNPs were regularly spherical. ζ-potential measurements were satisfactory and evidenced the importance of sucrose moiety on the polymeric system, which was responsible for the obtained negative surface charge, providing colloidal stability. The results of this study show that sucrose and cholic acid based polymeric conjugates can be successfully used to prepare PNPs with tunable physicochemical characteristics. In addition, it provides novel information about the materials used and the methods applied. It is hoped that this work will be useful for the development of novel carbohydrate based nanoparticles for biomedical applications, specifically for targeted drug delivery.

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Silva, Juliana Filipa Moreira da. "Modifications of the Synechocystis ΔsigF extracellular carbohydrate polymer and their impact on antitumor activity." Dissertação, 2020. https://hdl.handle.net/10216/132171.

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Silva, Juliana Filipa Moreira da. "Modifications of the Synechocystis ΔsigF extracellular carbohydrate polymer and their impact on antitumor activity." Master's thesis, 2020. https://hdl.handle.net/10216/132171.

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35

Pan, Yi-Fan, and 潘怡帆. "Preparation of Carbohydrate Polymers Dipersed Graphite or Graphene Composites for Electrochemical Sensors and Biosensor Applications." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/9m8vh6.

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碩士
國立臺北科技大學
化學工程研究所
105
The experiments are preparation of carbohydrate polymers dipersed graphite and graphene composites for electrochemical sensors and biosensor. First, fabrication of biosensor to detect the catechol(CC) using laccase immobilized on graphene-cellulose microfibers composite modified screen printed carbon electrode. It was linear over the concertation of CC ranging from 0.2 to 209.7 µM. The sensitivity and the detection limit of the biosensor is 0.932 µMµA-1 cm-2 and 0.085 µM, respectively. And a simple and robust dopamine sensor was developed using cellulose microfibers exfoliated graphite composite modified screen-printed carbon electrode. And the obtained response was linear in the ranging from 0.06 to 134.5 µM. Detection limit is 10 nM. On the other hand, a nitrobenzene(NB) sensor has been developed based on a glassy carbon electrode modified with the composite of chitin hydrogel stabilized graphite. Graphite-Chitin(GR-CHI) composite modified electrode is used to study the electrochemical reduction behavior of NB by cyclic voltammetry. It was found that GR-CHI composite modified electrode can detect the NB in the linear response range from 0.1 to 594.6 µM with the lower detection limit of 37 nM.

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Raposo, Cláudia Diana de Castro Bizarro Gomes. "Synthesis of novel saccharide-based polymers and their organization into nanoparticles." Doctoral thesis, 2020. http://hdl.handle.net/10362/115959.

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Targeted drug delivery systems are an effective and attractive strategy for improving traditional therapies, currently used in medicine. However, their development presents itself as a great challenge since it is necessary to build them taking into account several factors: their biocompatibility, biodegradation, bioavailability, toxicity, efficacy and, of course, their cost of production and development. In this work, functionalization strategies were developed for three commerciallyavailable polymers, namely poly(ethylene glycol) (PEG), epsilon-polycaprolactone (PCL) and poly(lactic-co-glycolic acid) (PLGA), to obtain drug transport systems. PEG has the advantage of being an economically accessible polymer, however it is hydrophilic which hinders its transformation into stable polymeric nanoparticles in aqueous solution. PCL and PLGA are hydrophobic polymers, ideal for sustained release systems, however they have a high cost, comparatively. For lectin recognition in target cells, four different carbohydrates were used: glucose, galactose, xylose and mannose. Coumarins were also used, which in addition to having biological properties also provide fluorescent properties to these systems, which allows them to be used additionally for diagnostic purposes. The commercially-available polymers were derivatized using simple reactions of esterification, amide formation, nucleophilic substitution, and cycloaddition (click chemistry reactions for the formation of triazoles), obtaining good yields with the exception of cycloaddition with unprotected sugar molecules whose yields were low, most likely due to the complexation of copper (I) with free hydroxyls. The use of known copper stabilizing additives did not reflect an increase in reaction yield. The final polymers were transformed into polymeric nanoparticles using the oil-inwater emulsification with solvent evaporation technique both for PEG and PCL derivatives, and nanoprecipitation with solvent evaporation method for PLGA derivatives. Derivatives of PEG formed mostly polymeric films, most likely due to the small size of the hydrophobic part of the polymer (coumarin moiety). In a preliminary test, the derivatives of PCL and PLGA were transformed into nanoparticles, but proper characterization regarding their encapsulation are needed. Nevertheless, the derivatives of PCL formed irregular spherical nanoparticles, with sizes ranging between 272 and 418 nm and low polydispersity indexes. Galacto-derivative formed a porous strucure with porous ranging from 1.6 to 3:6µm. A coumarin-derivative produced parallelepiped-like particles, with average height and width of 492 and 303 nm, respectively. PLGA derivatives formed stable spherical nanoparticles in aqueous solution (with the exception of the xylopyranose derivative that showed low stability, and a coumarin derivative that did not form particles), with smooth surface and with sizes between 157 and 195 nm and low rates of polydispersity.
Sistemas direcionados de veiculação de fármacos são uma estratégia eficaz e atrativa de melhorar as terapias tradicionais usadas atualmente em medicina. No entanto, o seu desenvolvimento apresenta-se como um grande desafio uma vez que é preciso construí-los tendo em conta vários fatores: a sua biocompatibilidade, biodegradação, biodisponibilidade, toxicidade, eficácia e claro, o seu custo de produção e desenvolvimento. Neste trabalho foram desenvolvidas estratégias de funcionalização de três polímeros comerciais, nomeadamente polietileno glicol (PEG), épsilon-policaprolactona (PCL) e poli(ácido láctico-co-glicólico) (PLGA), para a obtenção de possíveis sistemas de transporte de fármacos. O PEG tem a vantagem de ser um polímero acessível economicamente, no entanto é hidrofílico o que dificulta a sua transformação em nanopartículas poliméricas estáveis em solução aquosa. O PCL e PLGA são polímeros hidrofóbicos, ideais para sistemas de libertação prolongada, no entanto possuem um alto custo comparativamente. Para o reconhecimento pelas lectinas nas células alvo foram usados quatro glúcidos diferentes: glucose, galactose, xilose e manose. Também foram usadas cumarinas que para além de terem propriedades biológicas podem fornecer propriedades fluorescentes a estes sistemas, o que lhes permite serem usados adicionalmente como meio de diagnóstico. Os polímeros comerciais foram derivatizados com recurso a reacções simples de esterificação, formação de amida, substituição nucleofílica, e cicloadição (reacções click para formação de triazoles), tendo-se obtido bons rendimentos com a excepção da cicloadição com moléculas de açúcar desprotegidos cujos rendimentos foram baixos, muito provavelmente devido à complexação do cobre (I) com os hidroxilos livres. O uso de aditivos conhecidos de estabilização do cobre não reflectiu um aumento do rendimento reaccional. Os polímeros finais foram transformados em nanopartículas poliméricas usando a técnica de emulsificação óleo-em-água com evaporação do solvente para derivados do PEG e PCL, e nanoprecipitação com evaporação do solvente para derivados do PLGA. Derivados do PEG formaram maioritariamente filmes poliméricos, muito provavelmente devido ao pequeno tamanho da parte hidrofóbica do polímero (cumarina). Num teste preliminar os derivados de PCL e PLGA mostraram formar nanopartículas mas para a devida caracterização novos testes deverão ser feitos futuramente. Os derivados de PCL formaram nanopartículas esféricas irregulares e pouco estáveis em solução aquosa, com tamanhos entre 272 e 418 nm e baixo índice de polidispersividade. O galacto-derivado formou uma estrutura polimérica porosa, com poros de tamanhos entre os 1:6 and 3:6µm. Um derivado de cumarina formou estruturas do tipo paralelepípedo, com altura e largura média de 492 e 303 nm, respectivamente. Os derivados de PLGA formaram nanopartículas esféricas estáveis em solução aquosa (à excepção do derivado de xilopiranose que mostrou baixa estabilidade, e de um derivado de cumarina que não formou nanopartículas) com superfície lisa e tamanhos entre 157 e 195 nm e baixos índices de polidispersividade.

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Elkashef, Sara M., Mark H. Sutherland, Laurence H. Patterson, Paul M. Loadman, and Robert A. Falconer. "An optimised assay for quantitative, high-throughput analysis of polysialyltransferase activity." 2016. http://hdl.handle.net/10454/8803.

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Yes
The polysialyltransferases are biologically important glycosyltransferase enzymes responsible for the biosynthesis of polysialic acid, a carbohydrate polymer that plays a critical role in the progression of several diseases, notably cancer. Having improved the chemical synthesis and purification of the fluorescently-labelled DMB-DP3 acceptor, we report optimisation and validation of a highly sensitive cell-free high-throughput HPLC-based assay for assessment of human polysialyltransferase activity.

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Gannon, Mark. "Immunomodulatory effects of dietary fibre supplementation: effects on cytokine and antibody production and lymphocyte population profiles." Thesis, 2009. http://hdl.handle.net/10155/37.

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Gastrointestinal microflora has been shown to have a bi-directional relationship with the host immune system. A variety of fermentable carbohydrate polymers largely pass through the small intestine, providing fermentable substrates for gut microflora. Dietary fibre supplementation may provide a strategy for manipulating the intestinal bacterial profile, changing the interaction with the mucosal immune system, thereby modulating the host immune system. We used a BBc rat animal model to evaluate the effects of oat bran and wheat bran dietary fibre on the immune system. Previous collaborative efforts have shown that these dietary fibres can change the intestinal microflora, with wheat bran fibre showing a greater ability to influence colonic microbial community diversity. We have shown that dietary wheat bran fibre led to reduced IL-4 levels in the liver and T lymphocyte numbers in the Mesenteric Lymph Node and may be involved in reduced IgA levels in the cecal contents. In addition, IgA in the cecal contents was decreased while MLN B cell numbers increased in response to dietary wheat bran fibre. It was observed that neither wheat bran or oat bran treatments exerted any pro-inflammatory effects, with oat bran actually improving antioxidant status. These results suggest that both oat and wheat bran fibre treatments induce changes in the intestinal microflora, and that the microflora changes due to wheat fibre are associated with immunomodulatory effects on the host. This type of dietary fibre supplementation could ultimately provide a potential strategy for promoting health through microflora-associated effects on the immune system.

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Dissertations / Theses on the topic 'Carbohydrates polymer'

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