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Courtney, Margaret Ellen Louise. "Characterisation and modification of prokaryotic hyaluronic acid." Thesis, University of Strathclyde, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.249767.
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Schanté, Carole. "Chemical modifications of hyaluronic acid for the development of bioresorbable medical devices." Strasbourg, 2011. http://www.theses.fr/2011STRA6198.
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L’objectif de ce travail de thèse était de développer un nouveau dérivé d’acide hyaluronique (HA) ayant une action thérapeutique plus longue que les produits actuellement sur le marché. Une modification chimique efficace constistant en le greffage d’acides aminés sur les groupements carboxyliques de l’HA permis d’obtenir des dérivés ayant une meilleure résistance enzymatique in vitro comparée à l’HA de départ. Trois réactions d’amidation ont été évaluées pour l’obtention de taux de greffage élevés. La prochaine étape a porté sur la réticulation des dérivés HA-acides aminés qui a été accomplie avec le butanediol diglycidyl ether (BDDE) en tant qu’agent réticulant en milieu acide. Les hydrogels réticulés ainsi obtenus ont présenté une meilleure résistance in vitro à la dégradation enzymatique en présence de hyaluronidases en comparaison avec les hydrogels réticulés obtenus à partir de l’HA sans acide aminé et avec les produits commerciauxThe aim of this work was to develop a novel hyaluronic acid (HA) product having a longer therapeutic action compared to the products currently on the market. An efficient chemical modification consisting of grafting amino acids onto the carboxylic groups of HA showed to yield derivatives significantly more resistant to in vitro enzymatic digestion than the native HA. Three amidation reactions were evaluated for an efficient grafting of the amino acid onto the carboxylic groups of HA. The next step was to form crosslinked hydrogels from the HA-amino acid derivatives and was achieved by using the crosslinking agent butanediol diglycidyl ether (BDDE) in acidic media. The resulting crosslinked HA-amino acid hydrogels exhibited a higher in vitro resistance to hyaluronidase degradation compared to the hydrogels obtained from native HA in the same conditions, and compared to commercially available hyaluronic acid products
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Hrochová, Eliška. "Derivatizace hyaluronanu sodného jakožto nástroj pro zvýšení stability modelové artificiální synoviální kapaliny." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2021. http://www.nusl.cz/ntk/nusl-444537.
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This master thesis deals with the optimization of the procedure of modification of hyaluronic acid structure for the use in the artificial synovial liquids. Based on the literature research, the amino acid alanine was used for the modification of carboxylic group in the glucuronic acid. The main subject of study is the improvement of the stability and mechanical properties of synovial liquid. DLS microrheology, macrorheology, thermogravimetric analysis (TGA), multi-angle light scattering with flow-field flow fractionation (AF4-MALS) and infrared spectroscopy (FTIR) were used for characterization. The theoretical part of this theses submits review of the musculoskeletal system, role of hyaluronic acid in metabolism and summary of synovial liquid. The experimental part focuses on the measurement of the stability and mechanical properties of three artificial samples (first with no modification, second with modified hyaluronic acid and third with modified hyaluronic acid and chondroitin sulphate). These samples were compared with real horse synovial fluid and artificial viscosupplement Orthovisc®.
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Odehnalová, Nikola. "Příprava nanočástic a jejich využití jako kontrastních látek pro in vivo zobrazování." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2020. http://www.nusl.cz/ntk/nusl-414183.
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This diploma thesis deals with the optimalization of synthesis of gold nanoparticles and their surface modification allowing their use as contrast agents for in vivo imaging by CT. Gold nanoparticles were prepared by the Turkevich method and characterized by TEM, DLS, MADLS and UV -Vis. Their surface was functionalized with polyethylene glycol containing a thiol group forming a bond with the Au atoms in the surface of gold nanoparticles. The terminal end of the polymer was methylated or containing an aminooxy group forming an orthogonal bond with hyaluronic acid using click-chemistry. The eligibility for in vivo application of the prepared nanoparticles was verified with stability and cytotoxicity tests. The nanoparticles modified by methylated polyethyleneglycol were injected intravenously into a mouse and their application potential as contrast agents were verified by CT.
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Young, Denice Shanette. "Hyaluronic Acid-based Nanofibers via Electrospinning." NCSU, 2006. http://www.lib.ncsu.edu/theses/available/etd-08162006-095122/.
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Electrospinning is a novel technology that uses an electric field to form fibrous materials from a polymer solution. Unlike traditional spinning techniques, electrospinning can produce fibers, on the order of 100 nm, that can be utilized in applications where nanoscale fibers are necessary for specific applications, including tissue engineering and filtration. Outside of a smaller fiber diameter, electrospun nanofibers are also advantageous for biomedical applications because they have a larger surface area and pore size which promotes cell growth. A number of polymers have been electrospun successfully, including polyethylene (PEO) and polyvinyl chloride (PVC), which are two the most investigated electrospun materials. For the purpose of this study, hyaluronic acid (HA), a widely used biopolymer found in the extracellular matrix, was the chosen polymer to investigate the successful production of HA nanofibers for use in tissue engineering. Few studies have been conducted on electrospinning HA. Indeed, when this project was initiated, no investigations on electrospinning HA had been published. The goal of this research was to produce continuous fibrous strands of HA to be used as a mesh or scaffolding material. The high viscosity and surface tension of HA make it challenging to electrospin, as both are important parameters in successful production of nanofibers. To promote HA fiber formation by electrospinning, the effects of salt (NaCl), which is used to reduce the viscosity of aqueous HA solutions; molecular weight of the HA; and an additional biocompatible polymer (e.g., PEO) were investigated.
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Sjögren, Frida. "Microstructuring of Hyaluronic acid cell culture scaffolds." Licentiate thesis, Uppsala universitet, Mikrosystemteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-334653.
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Ren, Cindy D. "Injectable hyaluronic acid scaffolds for cartilage tissue engineering." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/46025.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 2008.Includes bibliographical references.
Every year tens of millions worldwide suffer from cartilage damage, caused by mechanical degradation, trauma or disease. Because of the lack of blood supply and low cell concentration within the tissue, cartilage has very limited regenerative ability. Although current treatments can provide symptomatic relief, the results vary greatly among individuals, and newly formed tissue often does not duplicate the structure, composition or mechanical properties of normal cartilage. Therefore, in recent years, tissue engineering has emerged as an alternative therapy. Tissue engineering enhances the body's natural healing capacity by providing cells, signaling molecules, and an environment in the form of a scaffold that is conducive to tissue growth. This project has focused on the development of a tissue engineering scaffold for cartilage regeneration. Disadvantages to current scaffolds include the fact that they require surgery for implantation, and that they are difficult to mold to the exact shape of the defect site. Hence, the motivation of this thesis is to develop an injectable scaffold that can be administered in a minimally invasive manner, and that allows for scaffold formation in situ, naturally shaping the construct into the shape of the defect, and thus promoting integration and stability To this end, we have developed a thermoresponsive injectable scaffold for cartilage tissue engineering. The scaffold was injected as a liquid at room temperature, and gelled at the target site in response to the change to body temperature, resulting in a biocompatible, bioresorbable substrate for tissue growth. Our approach involved suspending thermoresponsive liposomes, which encapsulated a crosslinking agent, in a polymer solution. At room temperature, the crosslinking agent was separated from the polymer by the lipid membrane, hence the precursor solution remained a liquid and injectable. Upon injection and exposure to body temperature, the lipids experienced a phase transition, which significantly increased the membrane permeability and led to the release of the crosslinking agent and reaction with the polymer, forming a networked scaffold.
(cont.) The scaffold system that we have chosen is a hyaluronic acid-tyramine system (HA-Tyr) that crosslinked in the presence of H202 and horseradish peroxidase (HRP) to form a hydrogel. Since HA, Tyr, H202 and peroxidases all occur naturally in the body, scaffold formation could take place with minimal toxicity and in the presence of cells as well as in situ. In order to impart temperature sensitivity to this system, HRP was encapsulated within liposomes, and it was shown that HRP was successfully retained at 25°C and released at 37°C. Upon liposome addition to the HA-Tyr/H202 solution, the precursor solution remained a liquid for hours at 25°C, yet gelation could be induced within minutes when exposed to 37°C. Furthermore, it was shown that gelation times could be adjusted to meet various clinical needs by modulating HRP encapsulation, liposome concentration and HA-Tyr concentration. In order to test the potential of the HA-Tyr system for cartilage production, porcine chondrocytes were encapsulated within HA-Tyr/H202/HRP hydrogels and implanted subcutaneously in mice. Harvested constructs were shown to achieve a GAG content of 1.2 wt% and demonstrated 40% of the collagen content of normal articular cartilage. Matrix production was found to be influenced by the initial cell density, scaffold degradation rate and Type II collagen concentration. The means of HRP delivery, whether by simple addition or through thermoreponsive liposomes, was not shown to have an effect on matrix production. Injected scaffolds were shown to achieve GAG and collagen levels similar to that of implanted scaffolds. As signaling molecules have been demonstrated to be potent chondrogenic inducers, PLGA-hydroxyapatite nanocomposite microparticles were utilized for the controlled delivery of TGF-[beta]1 and IGF-1. The rate of growth factor release was modulated by the molecular weight of PLGA within the microparticles; increasing molecular weight led to decreasing release rate. The nanocomposite microparticles were encapsulated within HA-Tyr/H202/HRP/chondrocyte constructs, which were then implanted subcutaneously in mice.
(cont.) Growth factor-induced enhancement of GAG and collagen production was found to be determined by the release rates of TGF-31 and IGF-1, multifactor release, and the dosage of nanocomposite microparticles. Injection of the microparticles with an HA-Tyr/H202/HRP liposome/chondrocyte/collagen solution also showed that the microparticles did not interfere with in situ scaffold formation, and could induce significant improvements to GAG and collagen production in the injectable system.
by Cindy D. Ren.
Ph.D.
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Almalik, Abdulaziz. "Hyaluronic acid-coated nanoparticles as biofunctional pharmaceutical carriers." Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/hyaluronic-acidcoated-nanoparticles-as-biofunctional-pharmaceutical-carriers(6812b8ca-0341-4473-abbe-b5059d30f8bc).html.
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In recent years, the use of nanotechnology for drug delivery purposes has witnessed a very significant growth aiming to improve the efficacy and/or reduce toxicity of existing drugs. This project aimed to design hyaluronic acid (HA)-coated chitosan-triphosphate (TPP) nanoparticles applicable for the delivery of genetic payload, and predominantly focused on the study of chitosan molecular weight-dependent effects.Firstly, we explored the effect of chitosan molecular weight (MW) on the physico-chemical characteristics and morphology/structure of chitosan-TPP nanoparticles and their functional behaviour. Combining dynamic light scattering and atomic force microscopy analysis allowed to highlight the influence of chitosan MW on the porosity, environmental response and HA adsorption of the resulting particles. For example, increasing chitosan MW provided increasingly porous nanoparticles. Upon coating with HA, HA showed a different adsorption mode depending on the nanoparticle porosity (and therefore on chitosan MW), with deeper penetration in more porous nanoparticles and the formation of an HA corona for less porous ones. This different mode of HA adsorption on nanoparticles appears to largely influence the enzymatically triggered payload release from the nanoparticles, the protein adsorption on the surface of the nanoparticles and also to affect the overall stability of the nanoparticles.As a spin-off of this study, we became interested in the effect of the different mode of HA adsorption described earlier on the way HA is presented to phagocytic cells (264.7 RAW macrophages), and therefore on the kinetics and possibly also on the mechanism of nanoparticles uptake. Here, we provide conclusive evidence that HA-coated nanoparticle internalisation is a CD44-mediated phenomenon. Interestingly, our data suggest that a better presentation of HA, i.e. hyaluronic acid less tightly complexed on the nanoparticle surface, is linked to both higher affinity and lower capacity/uptake rate. Paradoxically, particles with a lower affinity for CD44 may allow a more efficient HA-mediated delivery of payloads.Finally, we investigated the feasibility of CD44-dependent therapeutic approaches using HA-coated nanoparticles made from different chitosan MWs with or without a nucleic acid payload. The physico-chemical characteristics and nucleic acid encapsulation efficiency were compared. Transfection efficiency in cells characterised by a significantly different expression of CD44 and the possibility for the HA-coated nanoparticles to exert a direct anti-inflammatory effect were also analysed. HA-coated nanoparticles allowed successful entrapment and delivery of both siRNA and pDNA, with significant effects of the nanoparticle bulk structure ( i.e. chitosan MW). We also showed an unprecedented anti-inflammatory effect of HA-coated nanoparticles devoid of any payload, which was more potent than the effect resulting from soluble HA. We speculate that the different organisation and possibly different crowding and mobility of HA chains may give rise to significant effects on macrophage inflammatory activation possibly arising from clustered binding to HA receptors such as CD44. These results indicate the potentiality of CD44-mediated therapies using HA-coated nanoparticles.
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Ouasti, Sihem. "Hyaluronic acid biomaterials for perspective peripheral nerve regeneration." Thesis, University of Manchester, 2012. https://www.research.manchester.ac.uk/portal/en/theses/hyaluronic-acid-biomaterials-for-perspective-peripheral-nerve-regeneration(ec50c37c-7c3e-4e54-8b97-19cec79bcb17).html.
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This project focused on the design of a cellular scaffold applicable for the promotion of peripheral nerve regeneration. Firstly, we established a correlation between the organization of HA/PEG co-polymeric networks to their mechanical and degradability properties; cell adhesion was conferred to all gels by the incorporation of RGD peptides. Three families of hydrogels were produced using different procedures to permit an increasing physical incorporation of HA into a PEGDA-based network. From a comparative study of rheological properties and enzymatic degradability, co-networks obtained using thiolated HA as chain transfer agent during PEGDA photo-polymerization were selected for further biological investigations, aiming to link the cellular response of L929 murine fibroblasts (phenotype, proliferation rate, metabolic activity) to the composition and the consistency of selected hydrogels. Our findings showed that there is a clear relation between increasing hardness and increasing cell spreading/proliferation rate. This study illustrated the possibility to fine tune cell/material interactions with appropriate reactive processing techniques. As a spin-off of this study, we become interested in the interplay of cellular interactions in the use of materials that contain both HA and RGD peptides, which can bind at the same time to HA receptors such as CD44 and av integrins. We focused on soluble HA derivatives, with or without dandling RGD peptides. The kinetics and the mechanistic details of both HA and HA-RGD internalization were studied in a phagocytic model (J774.2 murine macrophages). HA-RGD showed a form of synergic binding to integrins and CD44 (HA receptor), whereas its uptake remained solely regulated by CD44 dwell-time on the cell membrane. This study demonstrated that the knowledge of the rate-determining steps of the uptake of a carrier is necessary for assessing its efficiency. In this case, the presence of multiple ligands on a carrier was beneficial in some respect, but may not be optimal to overcome internalization limitations that arise from the slow turnover of the determining receptor. Finally, we studied the relation between the regulation of the expression of CD44 / RHAMM (HA receptor mediated motility) and the motility of Schwann cells (peripheral glial cells) and stem cells differentiated into a glial phenotype. Rt-PCR and immuno-assay experiments suggested that RHAMM up-regulation is associated with glial differentiation and we speculate that in the future this HA receptor could be considered as a differentiation marker. We also illustrated the importance of HA / RHAMM interaction for the motility of glial cells. These results indicate the importance of HA in mediating glial cell function during peripheral nerve regeneration and have implications for therapeutic repair strategies.
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McLaughlin, Richard L. "Hyaluronic acid production in continuous cultures of Streptococcus zooepidemicus /." [St. Lucia, Qld.], 2005. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe19192.pdf.
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Hwang, Jason Jayjoon. "Hyaluronic acid hydrogel microspheres for delivery of protein therapeutics /." Thesis, Connect to this title online; UW restricted, 2007. http://hdl.handle.net/1773/7983.
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Myint, Pe. "Free radical reactions of hyaluronic acid in aqueous solution." Thesis, University of Salford, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.292943.
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Běťák, Jiří. "Technology of monofilamentous fibers based on oxidized hyaluronic acid." Doctoral thesis, Vysoké učení technické v Brně. Fakulta chemická, 2016. http://www.nusl.cz/ntk/nusl-263388.
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Předkládaná dizertační práce se zabývá vývojem technologie výroby nového typu biodegradabilních vláken na bázi oxidované kyseliny hyaluronové. V rámci práce je postupně představován vývoj jednotlivých jednotkových operací výroby, jejichž správné porozumění a schopnost jejich řízení jsou klíčové pro žádaný chod celé vícestupňové technologie. V rámci práce je představen nezbytný vývoj technologického zařízení, průběžně konstruovaného pro účely laboratorního testování a následně až po samotnou linku pro finální výrobu vláken, která byla realizována v roce 2015. V rámci dizertační práce jsou dále navrhovány možnosti dodatečné chemické úpravy vláken s ohledem na zvyšování jejich stability ve vlhkém prostředí. S ohledem na cílené aplikace vláken pro vnitřní chirurgické implantace, jsou v práci vlákna též hodnocena z hlediska jejich materiálové biokomaptibility (toxicity).
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Pei, Xiaoyin. "Acid modification of psyllium." College Park, Md.: University of Maryland, 2008. http://hdl.handle.net/1903/8963.
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Thesis (M.S.) -- University of Maryland, College Park, 2008.Thesis research directed by: Dept. of Nutrition and Food Science. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Di, Silvestro Matthew D. "Hyaluronic acid injections in the treatment of the osteoarthritic knee." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape9/PQDD_0002/MQ42061.pdf.
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Mohamad, Bustaman Ahmad Fahmi. "The effectiveness of intra-articular hyaluronic acid in temporomandibular disorders." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B44661150.
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Ibrahim, Samir. "The development of hyaluronic acid biomaterials for vascular tissue engineering." Connect to this title online, 2008. http://etd.lib.clemson.edu/documents/1233081308/.
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Brigham, Mark D. "Collagen and hyaluronic acid interpenetrating polymer networks for tissue engineering." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/45810.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2007.Includes bibliographical references (leaves 68-70).
Interpenetrating Polymer Networks (IPNs) represent a strategy for combining the properties of several polymeric materials into a single network. In this thesis, collagen and methacrylated hyaluronic acid are combined in IPNs to produce a range of new biocompatible. The fabrication method allows for control of compressive strength of the IPN hydrogels. The materials are confirmed to be homogeneous at microscopic scales with fluorescent techniques. The IPNs are used for cell encapsulation and have the potential to be used for surface cell culture. The mechanical properties can be adjusted to match those of cardiac tissue. Thus, when combined with the properties of biocompatibility, viable cell encapsulation, and cell culture, the collagenMeHA IPN hydrogels represent a powerful new material for tissue engineering applications.
by Mark D. Brigham.
M.Eng.
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Cadete, pires Ana cristina. "Hyaluronic acid nanocapsules for the intracellular delivery of anticancer drugs." Thesis, Angers, 2016. http://www.theses.fr/2016ANGE0071.
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Cette thèse de doctorat avait pour principal objectif le développement d’une méthode viable pour la formulation de nanocapsules d’acide hyaluronique (NCs HA) à des fins d’incorporation et de libération intracellulaire d’agents anticancéreux. La première étape de ce travail a visé le développement d’une méthode d’émulsion spontanée dans laquelle les NCs HA ont été formulées sans avoir recours à des solvants organiques, ni à un travail à haute température ou à un apport énergétique élevé, ce qui fournit des conditions optimales pour l’incorporation de biomolécules sensibles tout en diminuant l’impact environnemental. Un autre avantage de ce système est basé sur l’utilisation d’un dérivé de l’acide hyaluronique modifié hydrophobiquement, ce qui permet la formulation de NCs HA par des interactions hydrophobes, réduisant ainsi la toxicité due à l’addition d’un surfactant cationique. Une fois formulées, les NCs HA étaient caractérisées par une taille de 130 nm et un potentiel zeta négatif de -20 mV. La versatilité de ce nanotransporteur a été confirmée par l’incorporation de différentes molécules : le docétaxel, un agent cytostatique, a été incorporé au sein du coeur huileux, tandis que l’anti-gasdermin B, un anticorps monoclonal, a été piégé au sein de l’enveloppe polymérique. Le taux d’encapsulation du docétaxel était élevé, sa libération contrôlée et sa cytotoxicité maintenue sur la lignée cellulaire A549 de cancer du poumon. Enfin, l’anti-gasdermin B a été associée avec succès à l’enveloppe polymérique de NCs HA et, une fois à l’intérieur de la cellule, l’anti-gasdermin B était capable d’échapper au compartiment endosomal et d’effectivement cibler la protéine intracellulaire gasdermin B, entraînant une importante diminution du comportement migratoire et invasif des cellules de la lignée HCC1954 de cancer du sein. Tous ces résultats mettent en évidence le potentiel de NCs HA auto-émulsifiées en tant que systèmes multifonctionnels pour transporter divers agents anticancéreux, en particulier pour la libération intracellulaire d’anticorps monoclonaux, une approche ambitieuse qui pourrait passer au premier plan parmi les stratégies innovantes dans la lutte contre le cancerThe main goal of this thesis has been the development of hyaluronic acid nanocapsules (HA NCs) as a multifunctional platform for the encapsulation and delivery of diverse anticancer drugs, such as hydrophobic drugs and hydrophilic biomolecules. The first step was the development of a spontaneous emulsification method, where HA NCs were formulated without the need of organic solvents, heat or high energy input, providing conditions for the incorporation of sensitive biomolecules while decreasing the environmental impact. Another advantage of this system is based on the use of a hydrophobically-modified HA derivative that allowed the preparation of HA NCs by hydrophobic interactions rather than electrostatic forces and thus, reducing the toxicity associated to the addition of a cationic surfactant as a counterion. Once formulated, HANCs had a size around 130 nm and a negative zeta potential about -20 mV. Moreover, these nanocapsules were markedly stable under storage conditions and diluted in human plasma, taking forward this system as a potential carrier for intravenous administration. The versatility of this nanocarrier was confirmed by the incorporation of different molecules : docetaxel, a cytostatic drug, was incorporated into the oil core, whereas anti-gasdermin B, a monoclonal antibody, was entrapped into the polymeric shell. Docetaxel was highly encapsulated, released in a sustained manner and its cytotoxicity in A549 lung cancer cell line was maintained. Finally, anti-gasdermin B was successfully associated to the polymeric shell of HA NCs and its intracellular delivery confirmed by confocal microscopy. Once inside the cell, anti-gasdermin B was able to escape the endosomal compartment and to target the intracellular protein gasdermin B, promoting an important decrease in the migratory and invasive behavior of HCC1954 breast cancer cell line. All these results highlight the potential of self-emulsifying HA NCs as multifunctional systems to transport diverse anticancer drugs, with special emphasisin the intracellular delivery of monoclonal antibodies, an ambitious challenge that could open new avenues to fight cancer
En esta tesis se describe el desarrollo de un nuevo método sostenible para la elaboración de nanocápsulas de ácido hialurónico (NCs HA) como una nueva estrategia para el tratamiento del cáncer. Estas nanocápsulas permiten la incorporación de diferentes moléculas terapéuticas, tanto hidrofóbicas como hidrofílicas, y promueven su liberación en el interior de las células tumorales. En primer lugar, se desarrolló un método de autoemulsificación para la preparación de las NCs HA sin el uso de disolventes orgánicos, temperatura o aplicación de energía. Estas condiciones son ideales para la incorporación de biomoléculas lábiles, así como para reducir el impacto medioambiental del proceso. Otra ventaja del sistema reside en el uso de un derivado de HA modificado hidrofóbicamente que permite la formulación de las nanocápsulas sin la adición de un tensoactivo catiónico, reduciendo así la posible toxicidad del sistema. Las NCs HA semantuvieran estables en condiciones de almacenamiento y tras su dilución en plasma, manteniendo un tamaño nanométrico (130 nm) y una carga superficial negativa (-20mV), lo que corrobora su potencial para administración intravenosa. La versatilidad de este nanosistema fue confirmada mediante la incorporación de diferentes moléculas : docetaxel, un fármaco citostático encapsulado en el núcleo oleoso, y anti-gasdermina B, un anticuerpo monoclonal asociado a la cubierta polimérica. El docetaxel fue eficazmente encapsulado, manteniendo su citotoxicidad en la línea celular de cáncer de pulmón A549, mostrando una liberación del sistema de un modo controlado. Finalmente, la anti-gasdermina B fue asociada de manera eficaz a la cubierta poliméricade las NCs HA y su liberación intracelular confirmada por microscopía confocal. Una vezen el interior de la célula, la anti-gasdermina B abandonó el compartimento endosomaly bloqueó de manera efectiva la proteína intracelular gasdermina B, promoviendo así una importante reducción de la migración e invasión de las células HCC1954 de cáncer de mama. Estos resultados ponen de manifiesto el potencial de las NCs HA, preparadas por auto-emulsificación, como sistemas multifuncionales para transportar diversos fármacos, con especial énfasis en la liberación intracelular de anticuerpos monoclonales,una estrategia ambiciosa en la lucha contra el cáncer
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Ma, Weili. "Development of Hyaluronic Acid Hydrogels for Neural Stem Cell Engineering." Master's thesis, Temple University Libraries, 2015. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/340372.
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BioengineeringM.S.
In this work, a hydrogel made from hyaluronic acid is synthesized and utilized to study neural stem cell behavior within a custom tailored three dimensional microenvironment. The physical properties of the hydrogel have been optimized to create an environment conducive for neural stem cell differentiation by mimicking the native brain extracellular matrix (ECM) environment. The physical properties characterized include degree of methacrylation, swelling ratios, enzymatic degradation rates, and viscoelastic moduli. One dimensional proton nuclear magnetic resonance (1HNMR) confirms modification of the hyaluronic acid polymers, and is used to quantify the degree of methacrylation. Rheological measurements are made to quantify the viscoelastic moduli. Further post-processing by lyophilization leads to generation of large voids to facilitate re-swelling and cell infiltration. ReNcell VM (RVM), and adult human neural stem cell line derived from the ventral mesencephalon, are cultured and differentiated inside the hydrogel for up to 2 weeks. Differentiation is characterized by immunocytochemistry (ICC) and real time quantitative polymerase chain reaction (qRT-PCR).
Temple University--Theses
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Hokputsa, Sanya. "Chemical and hydrodynamic investigations of polysaccharides with pharmaceutical importance." Thesis, University of Nottingham, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.289502.
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Malay, Özge Batıgün Ayşegül. "Formation and characterization of silk fibroin/hyaluronic acid complexes and their use in iontophoretic drug delivery/." [s.l.]: [s.n.], 2005. http://library.iyte.edu.tr/tezlerengelli/master/kimyamuh/T000331.pdf.
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Elouzi, Abdurrahim A. "Tumour targeting of gene expression using hyaluronic acid - polypropylenimine dendrimer conjugates." Thesis, University of Strathclyde, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.424350.
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Sandqvist, Wedin Emma. "Optimization of Acidic Degradation of Hyaluronic Acid using Design of Experiments." Thesis, Linköpings universitet, Teknisk biologi, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-156273.
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Hyaluronic acid (HA) is an unbranched polysaccharide consisting of the repeating disaccharide unit β(1→4)-GlcA-β(1→3)-GlcNAc and is a naturally occurring biopolymer in bacteria and vertebras. HA is predominantly found in the extracellular matrix (ECM) and the in vivo function of HA can vary depending on molecular weight (Mw) for instance high Mw HA is reported to be anti-angiogenic while low Mw HA induces angiogenesis. HA is a popular component for hydrogels such as dermal fillers. HA is commonly used in dermal fillers. However, other materials, such as other polymers, can be used as well. The project goal was to investigate different degradation processes for production of target Mw HA. Alkaline and acidic degradation processes in combination with increased temperatures seemed as the most promising methods. Degradation tests performed both in aqueous solution as well as heterogeneously in ethanol were evaluated. The acidic degradation in aqueous solution was proven to have the largest degradation constant. Both a robustness test as well as a Design of Experiments (DoE) was performed to investigate the influence different factors had on the degradation speed. The investigated factors were HA concentration, HCl concentration and temperature. Temperature and HCl concentrations proved to be the most influencing factors and a model was developed in the DoE software MODDE to describe how the factors influenced the degradation constant. The model was established as a good significant model with a Q2 value of 0.998 and relative standard deviation (RSD) value of 0.022 after a logarithmic transformation was performed as well as a simplification of the model by excluding some of the factor interactions. The acidic degradation method also proved to be a highly robust method which easily could be used to produce target Mw HA.
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Mustafa, Amjad. "Cd44-Hyaluronic Acid Interactions in Il-2 Induced Vascular Leak Syndrome." Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/33821.
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Immunotherapy with IL-2 is accompanied by severe toxicity leading to development of vascular leak syndrome (VLS). Previous studies from our laboratory demonstrated that CD44 knockout mice exhibit marked decrease in IL-2 induced VLS, thereby suggesting a role for CD44 in VLS. In the current study we tested whether use of mAbs against CD44 or hyaluronic acid (HA), the ligand for CD44, can abrogate IL-2 induced VLS. Administration of IL-2 (75,000 U/mouse, three times a day for 4 days) into C57BL/6 mice triggered significant VLS in the lungs and liver. Interestingly, HA caused a marked increase in IL-2-induced VLS in the lungs and liver. In contrast, use of anti-CD44 mAbs reduced IL-2-induced VLS in the lungs and liver. The change in VLS seen following HA or anti-CD44 mAbs treatment was not due to any defect in lymphocyte migration or homing to various organs because histopathological studies in these mice demonstrated significant and often greater perivascular infiltration of lymphocytes when compared to mice treated with IL-2 alone. However, HA treatment exhibited a marked increase in IL-2-induced lymphokine-activated killer (LAK) cell activity while anti-CD44 mAbs treatment led to a significant decrease in IL-2-induced LAK cell activity. These studies demonstrate that HA or anti CD44 mAbs may serve as a useful tool to selectively alter the LAK activity as well as to prevent the toxicity induced by IL-2. Altering CD44-HA interactions in vivo may offer a novel therapeutic approach to prevent endothelial cell injury by cytotoxic lymphocytes in a variety of clinical diseases.Master of Science
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Spelling, Victor, Mathias Axelsson, Lovisa Ringström, af Rosenschöld Johanna Munck, and Anton Lindblad. "Mapping the intrinsic viscosityof hyaluronic acid at high concentrations of OH-." Thesis, Uppsala universitet, Institutionen för teknikvetenskaper, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-325348.
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Hyaluronic acid is commonly used in dermatological fillers in the form of gels. It is established how these gels' firmness is affected by the amount of cross linker and hyaluronic acid respectively. However, the effect of hydroxide ions in solution is rather unknown. This thesis examines how the alkalinity of the solvent affects the intrinsic viscosity of 3 MDa hyaluronic acid by using the method of Ubbelohde capillary viscometry. Sodium hydroxide solutions between 2 and 10 wt% were prepared to study the variation in intrinsic viscosity at concentrations relevant for cross linking (1<wt%). From these respective solutions, four solutions of different mass concentrations of hyaluronic acid were made. The flow time of respective samples were measured between two points in the capillary viscometer in a controlled temperature of 25 °C with an SI Viscoclock to ensure a high accuracy.From the resulting flow times, the intrinsic viscosity was calculated. The intrinsic viscosity varied between 0,55 and 0,70. The relation between intrinsic viscosity and hydroxide ion concentration had a correlation coefficient r < 0,001. No trend could be ensured as the confidence interval for the intrinsic viscosity at the different concentrations was too large.
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Li, Ruifu. "A Novel Thiolated Hyaluronic acid Hydrogel for Spinal Cord Injury Repair." Thesis, Université d'Ottawa / University of Ottawa, 2014. http://hdl.handle.net/10393/31410.
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Spinal Cord Injury (SCI) often causes cell death, demyelination, axonal degeneration and cavitation, resulting in functional motor and sensory loss below the site of injury. In an attempt to overcome SCI, the regenerating neurons require a permissive environment to promote their ability to reconnect. We report a novel thiolated hyaluronic acid (HA) hydrogel scaffold that can be used to repair the injured spinal cord. More specifically, thiolated hyaluronic acid hydrogels with varying thiol concentrations were successfully synthesized. The amount of thiol groups was measured spectrophotometrically using Ellman’s test. HA gels with different crosslinking densities were synthesized and the water content of the hydrogels was determined. The thermal behavior of the HA gels were studied by DSC. The strength of the hydrogels with varying thiol group content was evaluated by a rheometer. In addition, in vitro enzymatic degradation was performed through submerge the hydrogels in 200U/ml of hyaluronidase solution and incubate at 37°C. According to the result of the present study, this novel hydrogel shows great potential to serve as a 3D cell-patterning scaffold which can be inserted into a hollow fiber channel that could be used to promote regeneration after the SCI.
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Sundström, Gunnel. "Hyaluronan in normal and malignant bone marrow : a clinical and morphological study with emphasis on myelofibrosis /." Umeå : Public Health and Clinical Medicine, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-658.
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Kuo, Chung-Gan, and 郭仲帆. "Modifications of Hyaluronic Acid for Hydrogel Formation." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/53045021471588431304.
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碩士國立陽明大學
醫學工程研究所
97
Hyaluronic acid (HA) is a linear unbranched negatively charged polysaccharide comprised of N-acetylglucosamine and D-glucuronic acid. HA is capable of forming a network of hydrogel by physical entanglements or chemical crosslinks with great potential in biomedical application. Therefore, the aim of this study was to develop a new technology platform for fabricating HA hydrogel via chemical crosslinking process. We have used N, N’-carbonyldiimidazole(CDI) to modify the carboxyl groups of short-chain hyaluronic acid (sHA, MW of 4.7k) and found that longer reaction time resulted in a lower grafting ratio of CDI probably due to undesired intra- and inter-molecular crosslinkings. The sHA-CDI molecules of 56% grafting ratio could be obtained by controlling the molar ratio of sHA/CDI at 1/4 and reacted for 2 hours at 25oC. In addition, the hyaluronic acid was aminated by reacting long-chain hyaluronic acid (MW of 900K) molecules with adipic dihydrazide (ADH) via the activation of carboxylic acids by 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC). By adjusting the molar ratio of HA/ADH at 1/10, HA-ADH of 56% grafting ratio could be obtained after 3 hours reaction at 25℃. A hydrogel network of HA (HAX) with crosslinking extent of 19% to 70% could be fabricated by mixing HA-CDI and HA-ADH in a series of combination. The swelling ratio decreased from 48% to 30% by increasing the extent of crosslinking, whereas the water content remained in the range of 96%-98%. The results of mechanical testing showed that the compression modulus increased from 0.007 MPa to 0.23 MPa with increasing crosslinking ratio. All HAX gels had about the same in vitro degradation rate with 55%~60% degraded in 7 days. The more stable HAX gel synthesized in this study is better than the HAX gel previous documented.
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Chou, Yi-Feng, and 周宜鋒. "Surface Modification of Electrospun Hyaluronic Acid and Its Derivatives Nanofiber on Silicone Hydrogel Membrane." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/13704155289460017035.
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碩士中原大學
生物醫學工程研究所
98
Abstract Silicone hydrogel contact lenses have high oxygen transmissibility that makes them suitable for extended wear, but their hydrophobic surfaces cause discomfort to the cornea during extended wear. This study aims to adjust the hydrophobic characteristics of the silicone hydrogel by combining siloxane-containing monomers of (trimethyl-siloxy)silyl-propyl methacrylate (TRIS) with hydrophilic monomers, such as 2-hydroxyethyl methacrylate and N-vinyl-2-pyrrolidone. A crosslinking agent and a photoinitiator were also used to fabricate the silicone membrane. Hyaluronic acid (HA) was mixed with polyvinyl pyrrolidone (PVP) to form fibrous membranes using the electrospinning technique. Glycidyl methacrylate-hyaluronic acid (GMHA) was successfully synthesized. Proton nuclear magnetic resonance spectrra showed that the GMHA proton signals were present at 5.6 and 6.1 ppm, representing the vinyl functional group. A solution of GMHA with PVP was used to form fibers by electrospinning. When TRIS was increased by 30-50 vol%, the water content of TRIS-based silicone hydrogel decreased from 35 to 28%. The elastic modulus increased from 0.8 MPa to 4.4 MPa after treatment. The transmittance of the silicone membrane was about 80-95%T. The contact angle at the surface of the silicone membrane was about 92-103o. Scanning electron microscopy analysis showed that the HA-PVP fiber diameters were in the range of 100-680 nm at 25 oC and in the range of 140-770 nm at 50 oC. When silicone membranes were coated with HA-PVP fibers using a physical adsorption procedure, the contact angle decreased from 62 o to77o. In contrast, chemical modification of silicon membranes through ozone treatment and coating with electrospun GMHA-PVP yielded contact angles of 59-77o. Therefore, the techniques presented here have successfully improved the hydrophilic characteristics of a silicon hydrogel membrane.
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吳政倫. "An Investigation on Surface Modification of Ultra High Molecular Weight Polyethylene with Hyaluronic Acid and its Antiwear Performance Research." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/83418286566582215162.
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碩士國立臺灣海洋大學
機械與機電工程學系
100
A mimic surface modification was implemented on a high pressure crystallized ultrahigh molecular weight polyethylene (UHMWPE) as an artificial cartilage material. Hyaluronic acid (HA) was coated on the UHMWPE surface pretreated by a series of processes, including the treatment of O2- plasma, ethylenediamine solution, and HA one. The modified samples were verified by water contact angle measurement, and Fourier transform infrared spectrometry. The HA layer was also quantitatively evaluated by the carbohydrate chemistry assay according to the absorbance of the incident light. The tribological performance of the samples was conducted by a pin-on-disk test rig which was lubricated by a normal saline under an average pressure of 18 MPa and a sliding speed of 0.03 m/s for 40 h. The wear resistance of the solid UHMWPE specimen is confirmed to be significantly enhanced by the HA coating. However, for the porous UHMWPE, it is not -instead.
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Ho, Yueh-chia, and 何岳珈. "Effect of surface modification with chitosan and hyaluronic acid on anti-protein-adhesion and antibacterial activity of silicone hydrogel contact lenses." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/u9665x.
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碩士國立臺灣科技大學
材料科學與工程系
104
This study is about modification of silicone hydrogel contact lenses. The resultant contact lenses exhibited anti-bacterial activity, anti-adhesion of proteins and high hydrophilicity. Our goal is to create more comfortable and longer-term contact lenses. Antibacterial activity and anti-protein deposition are the most important consideration in the contact lenses. People use contact lenses by touching the contact lenses with their finger. This contact may contaminate contact lenses and lead to inflammation and pain on the cornea. Therefore, anti-bacterial activity is needed to prevent pathogenic problems. Anti-protein deposition is needed to prolong the wearing time of contact lenses. Deposition of proteins and lipids will reduce visual contrast. It was one of the reason contact lenses is uncomfortable to wear. To meet our goal, chitosan (CS) and hyaluronic acid (HA) will be covalently bonded to the surface of the contact lenses (PDMS-CS-HA). According to these ways, we can enable to inhibiting bacteria growth and protein deposition on the contact lenses surface. However, the optical transparency, water content, oxygen permeability, tensile strength and modulus will not significantly change. The overall results demonstrated that new modification of contact lenses has a good potential in the application of ophthalmic lenses
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Dvořáková, Martina. "Optimalizace preparativní LC-MS metody frakcionace oligosacharidů hyaluronanu." Master's thesis, 2013. http://www.nusl.cz/ntk/nusl-321468.
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Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Biophysic and Physical Chemistry Candidate: Bc. Martina Dvořáková Supervisor: Doc. Ing. Alice Lázníčková, CSc. Consultant: Mgr. Martina Hermannová, Ph.D. Title of diploma thesis: Optimization of preparative LC-MS method for fractionation of oligosaccharides of hyaluronanu This diploma thesis deals with optimization of LC-MS method for analysis of hyaluronan oligosaccharides in preparative mode. The theoretical part summarizes available information about biological and chemical properties of hyaluronic acid. Hyaluronic acid is easily enzymatically degradable by mammalian hyaluronidases that produce hyaluronan oligosaccharides. The biological function of these degradation products depend on their molecular weight. High-performance liquid chromatography is mainly used for separation and purification of hyaluronan oligosaccharides. A new method for the determination of hyaluronan oligosaccharides is based on a combination of separation techniques and mass spectrometry. The experimental part deals with optimization of ionisation conditions for electrospray ionization mass spectrometry in positive and negative ion mode. In the first step, we focused on setting of capillary voltage, cone voltage, desolvation temperature, flow...
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Pedrosa, Sílvia Santos. "Hyaluronic acid nanogels." Doctoral thesis, 2016. http://hdl.handle.net/1822/43238.
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Programa Doutoral em Engenharia Biomédica.Nanogéis poliméricos são nanopartículas que possuem uma estrutura tridimensional constituida por um polímero hidrofílico conjugado ou reticulado. O ácido hialurónico é um polissacarídeo aniónico, biodegradável, biocompatível e não-imunogénico, abundante no corpo humano. Neste trabalho descrevemos a produção de um nanogel de ácido hyalurónico através da conjugação de uma molécula hidrofóbica tiolada à cadeia hidrofílica de ácido hyalurónico. O conjugado resultante é capaz de se autoorganizar em estruturas nanométricas, em meio aquoso, de um modo versátil, fácil e reprodutível. Adicionalmente, o nanogel foi reticulado através de uma ligação dissulfito, recorrendo a um agente reticulante reativo com grupos sulfídrilo. O nanogel foi caracterizado quanto à sua estrutura, tamanho, forma, potencial zeta, estabilidade e capacidade de aprisionar moléculas hidrofóbicas. O sucesso da reticulação do nanogel foi confirmado por espectroscopia de ressonância magnética nuclear 1H, microscopia crio-eletrónica de varrimento e dispersão dinâmica de luz e comportamento em ambiente redox. O nanogel desenvolvido foi ainda estudado quanto à sua biocompatibilidade, imuno-compatibilidade e hemato-compatibilidade. Com esse intuito, o nanogel foi incubado com uma série de linhas celulares representativas de órgãos e tecido humanos, relevantes - 3T3, HMEC, A549 e RAW 264.7. O nanogel provou não afectar a atividade metabólica e proliferação celular, ou a integridade da membrana celular. Do mesmo modo, também não observamos nenhum efeito apoptótico em nenhuma das concentrações e linhas celulares testadas. Para além disso, o nanogel provou não ativar a cascata do complemento através da clivagem da proteína C3 e provou também não possuir atividade hemolítica de acordo com o Procedimento Padrão para a Avaliação da Atividade Hemolítica em Materiais, da Sociedade Americana de Testes em Materiais. Uma das características relevantes do ácido hialurónico aplicada à nano-medicina é o seu potencial de direcionamento para receptores celulares, nomeadamente receptores CD44 e Receptores de Mobilidade para o Ácido Hialurónico. Deste modo, investigamos o direcionamento do nanogel para células que sobreexpressam receptores CD44 – Cancro do pulmão das não-pequenas células. O direcionamento in vitro foi avaliado por citometria de fluxo e microscopia confocal e a biodistribuição in vivo foi avaliada por imagiologia em tempo real nãoinvasiva de infravermelho próximo (NIR). Resultados demostraram uma elevada internalização celular em células que sobreexpressam receptores CD44, in vitro, e uma seletividade in vivo para o tecido tumoral. Também quisemos estudar a influência das sondas NIR usadas nos estudos de biodistribuição. Portanto, desenvolvemos um estudo comparativo da farmacocinética in vivo, de duas sondas de NIR diferentes – Cy5.5 e Alexa Fluor 680. Por fim, estudamos o mecanismo de endocitose através do qual o nanogel interage com as células recorrendo à tecnologia de siRNA para regular a expressão de proteínas alvo envolvidas no processo de endocitose. Os resultados revelaram que, o nanogel é internalizado por um mecanismo dependente de energia que parece ser mediada pela Caveolina e também pela Claterina. Finalmente, o nanogel foi usado como veículo para o transporte de rifampicina ou outros péptidos antimicrobianos, no tratamento de macrofagos infectados com Mycobacterium. Em resumo, o nanogel apresenta características promissoras como sistema reticulado, no direcionamento de fármacos via endocitose mediada por receptors para o ácido hialurónico.
Polymeric nanogels are hydrogel nanoparticles with a tridimensional structure that consist in a conjugated or crosslinked hydrophilic polymer. An exquisite representative of this group of polymers is, hyaluronic acid. Hyaluronic acid is an anionic polysaccharide biodegradable, biocompatible and non-imunogenic, ubiquitous of the human body. The present work comprehends the production of a hyaluronic acid nanogel by the conjugation of a thiolated hydrophobic molecule to the hydrophilic backbone of hyaluronic acid. The resulting conjugate is able to self-assemble in aqueous environment into nanosized structures in a versatile, easy and reproducible manner. Further, nanogel was crosslinked by dissuldie bond, resourcing to a sulfhydryl reactive homobifunctional crosslinker. Nanogel were characterized as to its - structure, size, shape, zeta potential, stability and ability to entrap small hydrophobic molecules. Also, reticulation was confirmed by 1HNMR, UV–Vis spectroscopy, cryo-field-emission scanning electron microscopy, dynamic light scattering characterization and redox-sensitive performance. Engineered nanogel was further studied as to its biocompatibility, immunocompatibility and hemocomptability. For that purpose, nanogel was incubated with a collection of cell lines representative of relevant human tissues - 3T3, HMEC, and RAW 264.7 cells. Nanogel proved to not affect cells metabolic activity and proliferation, or cellular membrane integrity. Also, we didn’t observe any apoptotic effect at any nanogel concentration and cell lines tested, using the Annexin V-FITC test. Moreover, nanogel proved to not activate the complement cascade by C3 cleavage and to be non-hemolytic according to Standard Practice for Assessment of Haemolytic Properties of Materials from the American Society for Testing Materials. Among the exciting features of hyaluronic acid in nanomedicine applcations is the potential of active targeting for cell surface receptors, namely CD44 and Receptor for Hyaluronan Mediated Motility. Thus, we investigated nanogel targetability, towards CD44 over-expressing cells – Non-small cancer lung cells. In vitro and in vivo targeting was assessed by flow cytometry and confocal fluorescence microscopy and non-invasive real time near-infrared (NIR) imaging in healthy and tumour bearing mice. Results revealed high in vitro cellular uptake by CD44 overexpressing cells and in vivo selective targeting towards tumour tissue. We also investigated the influence of the NIR probe used in biodistribution studies. For that reason, we performed a comparative study of in vivo pharmacokinetics of two different NIR probes - Cy5.5 and Alexa Fluor 680. We further studied the endocytic mechanism through which nanogel interacted with cells interface resourcing to siRNA machinery to regulate expression of key endocytic proteins. Results revealed that nanogel endocytosis occurs through an energy dependent pathway and seems to occur predominantly through caveolae-mediated endocytosis and also, clatherin-mediated endocytosis. Finaly, the HyA-AT nanogel was subsequently tested as drug carrier for the intracellular delivery of Rifampicin or an antimicrobial peptide to Mycobacterium infected macrophages. Our data collectively suggest that HyA-AT nanogel may have potential as intracellular delivery system of therapeutic cargo via endocytosis mediated by hyaluronic acid receptors.
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Yang, Pei-Fen, and 楊佩芬. "Oligosaccharides of hyaluronic acid preparation using recombinant phage hyaluronic acid lyase." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/94367464559353152778.
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博士國立臺灣科技大學
化學工程系
95
Oligosaccharides such as isomaltoses isomaltotrises, fructooligosaccharides and galactooligosaccharideshave been used as supplementary nutrition fool. Clinical studies have show that administering several oligosaccharides can increase the number of friendly bacteria such as Bifidobacteria and Lactobacillus species in the colon while simultaneously reducing the population of harmful bacteria. Recently, oligomers of hyaluronic acid (Oligo-HA) have been found to specific beneficial biological activity. In order to further test its efficacy, an efficient oilgo-HA preparation method has to be developed. In this study, the hyaluronic acid (HA) lyase of Streptococcus pyogenes bacteriophage H4489A was expression in Escherichia coli, not only purified from crude extract directly by by immobilized metal affinity magnetite (IMAM) but also immobilized on IMAM for oligo-HA preparation. HA is a linear, unbranched polysaccharide made of alternating N-acetyl-Dglucosamine and D-glucuronic acid. HA is commercially obtained from rooster combs and certain attenuated strains of group C Streptococcus which synthesize this compound naturally as part of their outer capsule. However, these are less-than-ideal sources. All rooster comb-based HA products carry warnings directed to those who are allergic to avian products, while Streptococci can be difficult or expensive to ferment, are challenging to genetically manipulate, and have the potential to produce exotoxins. Therefore, the hasA gene and hasB gene from Streptococcus zooepidemicus, which encodes the enzyme hyaluronan synthase and UDP-gluronic acid dehydrogenase respectively, was cloned and expressed in E. coli in order to develop a new and safer HA producing strain. However, due to the very different membrane structure, the production of HA in the recombinant Gram (-) E. coli was about thousand fold less that in Gram (+) S. zooepidemicus. Usually HA isolation from the crude HA extract involves with quaternary ammonium compound such as cetyl pyridinium chloride (CPC) or ethanol precipitation. Instead of using filtration or centrifugation to recover the precipitate, submicron size magnetite modified with various positively charged functional groups was prepared to recover HA through electrostatic interaction under magnetic field from fermentation broth. Chitosan-magnetite rather than NH2-magnetite has demonstrated its HA adsorption ability and can achieve 92.5 % elution yield, the purified HA is free from proteins contamination. Unlike most bacterial HA lyase, HA lyase of Streptococcus pyogenes bacteriophage specifically cleaved HA to unsaturated oligosaccharides which has an optimum absorption at 232 nm. The limiting absorbance showed linearity in the range of concentrations. Based on this fact, a specific, simple, easy to apply, low cost, and fast enough method was developed for routine determination of HA concentration of a microbial HA production process. HA lyase of Streptococcus pyogenes bacteriophage was employed to prepare oligo-HA. The gene of this phage enzyme was over-expressed in E. coli. Metal chelating ligands were immobilized metal affinity magnetite (IMAM). This IMAM micro-particle was employed to directly recover the recombinant HA lyase from the unclarified crude extract. The HA lyase specifically adsorbed on IMAM was directly used for oligo-HA preparation. The one-step purification-immobilization of HA lyase in reduced the inevitable losses of enzymatic activity during HA lyase purificartion and immobilization. However, the activity of HA lyase immobilized by either IMAM or Pharmacia’s IMAC gel reduced to 10 % of the free HA lyase. The mass transfer resistance between the immobilized HA lyase and the high molecular weight substrate HA contributed to the low activity. On the other hand, the stability of this immobilized HA satisfactory since its activity maintained at the same level after the 2nd repeated used.
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Zawko, Scott Andrew. "Hyaluronic acid hydrogel materials." 2008. http://hdl.handle.net/2152/9776.
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Hyaluronic acid (HA) is one of the primary chemical building blocks of the extracellular matrix and thus is an attractive material for biomedical applications. FDA approved HA-based materials are available as dermal fillers, joint viscosupplements, vitreous substitutes, and abdominal adhesion barriers. The engineering of new HA-based materials and applications is an active area of research. Here we develop several new types of HA-based hydrogels with unique and useful properties. To address the challenge of delivering hydrophobic drugs from hydrophilic hydrogel matrices we have grafted HA hydrogels with [Beta]-cyclodextrin to create hydrogels capable of binding poorly water soluble drugs. To create HA hydrogels with unique anisotropic swelling behavior we have developed a dual-crosslinking technique in which a super-swelling chemically crosslinked hydrogel is patterned with low-swelling photocrosslinked domains. When this dual-crosslinked hydrogel is swelled it contorts into a new shape because of differential swelling among photopatterned regions. To address the challenge of creating hydrogel scaffolds with biomimetic branched porosity we have invented a "crystal templating" technique. This technique grows dendritic crystals throughout a biopolymer solution, crosslinks the biopolymer around the crystals, and washes the crystals away to yield a hydrogel with a dendritic macroporous network. Lastly, we invented a method for patterning a substrate with a microarray of hydrogel compartments. A microarray of living cells is obtained when cells are seeded on the hydrogel patterned substrate. This method addresses the need for an inexpensive, simple method for obtaining living cell microarrays that does not require clean room labs and lithographic expertise. Each of these new materials were based on hyaluronic acid hydrogels but the methods are generalizable to hydrogels of other polymers too. In conclusion, the novel methods in this dissertation are a significant contribution to the engineering of HA-based materials.text
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Hu, Yu-Peng, and 胡育朋. "Synthesis of Hyaluronic Acid." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/02685416513894731630.
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碩士國立中央大學
化學研究所
93
Hyaluronic acid is a linear, non-sulfated, and extracellular polymer of disaccharide repeating units which are termed as [4)-β-D-glucuronic acid-(1→3)-β-D-N-acetyl glucosamine-(1→]n. The most important biological functions of hyaluronic acid include cell-cell aggregation, cell-cell communication, cell adhesion, angiogenisis, and tumor metastasis. We tried to synthesize the p-methylphenyl-1-thio-β-D-glucose-derived 39 and D-glucosamine-derived 52 by utilizing the one-pot protection strategy which was successfully developed in our laboratory. The acceptor 36 was able to be prepared from compound 39 in two steps. On the other hand, donor 50 can be afforded by using 52 as starting material in two steps. Coupling of 36 with 50 gave the β-linked disaccharide 49 in high yield and selectivity. The target molecular 63 could be generated via the subsequent functional group transformation in 6 steps.
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Barros, Óscar José Maciel. "Development of hyaluronic acid-doxorubicin nanogels." Master's thesis, 2016. http://hdl.handle.net/1822/44772.
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Dissertação de mestrado em BioengenhariaCancer is the leading cause of death in the world. Cancer research is continuously growing aiming to achieve more efficient therapies and early diagnostics. Different challenges arise, concerning the development of efficient drug delivery systems compared to conventional therapies, such as chemotherapy. New formulations promoting a controlled drug distribution, potentiating selective and efficient pharmaceutical actions, have been developed. Nanogels, produced by self-assembly of chemical modified natural polymers, are suitable for this purpose since they are able to encapsulate the hydrophobic drugs, physically or chemically. The use of labile linkages, to stabilize drugs, allows a selective drug release, such as pH-sensitive hydrazone. Doxorubicin is a drug currently used in chemotherapy, however, a major drawback remains its toxicity to healthy tissues, when used in high dosages, and the development of multi-drug resistance during prolonged treatment. Doxorubicin can be conjugated with hyaluronic acid, a natural polymer abundant in the human body, via hydrazone or amide linkages. The main goals of this work consist in the development of hyaluronic acid-based nanogels for cancer therapy with doxorubicin, as well as the incorporation of 𝘺-Fe2O3 into the nanogels to develop a theranostic formulation. Chemical modifications were performed on the hyaluronic acid to obtain an amphiphilic polymer grafted with doxorubicin via hydrazone or amide linkage. Doxorubicin content, average size and polydispersity index were evaluated. The most promising nanogels were further characterized concerning release profile at different pH, cytotoxicity and physical incorporation of 𝘺-Fe2O3. Hyaluronic acid-doxorubicin conjugates, via hydrazone, were produced in PBS pH 7.4, containing 22 μg DOX/mg, an average size of 100 nm and a polydispersity index around 0.5. The conjugation, via amide, was performed in DMSO, leading to a doxorubicin content of 29 μg DOX/mg, an average size of 70 nm and a polydispersity index around 0.45. The release studies indicated a satisfactory release at pH 5.0 (lysosomal pH) although exhibiting some release at pH 7.4 (extracellular pH). 𝘺-Fe2O3 stabilization into nanogels, designed as nanomagnetogels, lead to 0.6-0.9 mM of stabilized 𝘺-Fe2O3. Concerning the cytotoxicity assay performed using A549 cell line, hyaluronic acid-doxorubicin conjugate via amide presented a fast action and promoted a decrease in cell viability. In summary, hyaluronic acid-doxorubicin nanogels were produced using a pH-sensitive linkage, hydrazone, and amide linkage. The nanogels exhibited interesting characteristics for drug delivery applications envisaging more effective therapies, even though further optimizations are required. 𝘺-Fe2O3 incorporation was accomplished allowing imaging detection for diagnostic purposes or therapy evaluation along with the controlled drug release.
O cancro é a principal causa de morte no mundo. A investigação na área do cancro está em evolução contínua, e tem como objetivo alcançar terapias mais eficientes e diagnósticos precoces. Diferentes desafios vão surgindo, relativamente ao desenvolvimento de sistemas de entrega de fármacos eficientes em comparação com as terapias convencionais, como a quimioterapia. Têm sido desenvolvidas novas formulações que promovam uma distribuição controlada do fármaco, potenciando uma ação farmacêutica seletiva e eficiente. Os nanogéis, produzidos por auto-organização de polímeros naturais quimicamente modificados, são adequados para este objetivo, uma vez que permitem encapsular fármacos hidrofóbicos, de forma física ou química. O uso de ligações lábeis, para estabilizar os fármacos, permite uma libertação seletiva, tais como as ligações hidrazona, sensíveis ao pH. A doxorrubicina é um fármaco usado atualmente em quimioterapia, contudo, o seu maior problema é a toxicidade em tecidos saudáveis, quando usada em doses elevadas, e o desenvolvimento de multirresistência durante tratamentos prolongados. A doxorrubicina pode ser conjugada ao ácido hialurónico, que é um polímero natural abundante no corpo humano, através de uma ligação hidrazona ou amida. Os principais objetivos deste projeto consistem no desenvolvimento de nanogéis de ácido hialurónico e doxorubicina para tratamento do cancro, assim como a incorporação de 𝘺-Fe2O3 nos nanogéis, para o desenvolvimento de formulações teranósticas. O ácido hialurónico foi modificado quimicamente para se obter um polímero anfifílico, o qual foi conjugado com a doxorrubicina por ligação hidrazona ou amida. A quantidade de doxorrubicina ligada, o tamanho médio e o índice de polidispersidade foram avaliados. Os nanogéis mais promissores foram ainda estudados em ensaios de libertação a diferentes pH, citotoxicidade e incorporação de 𝘺-Fe2O3. Os conjugados de ácido hialurónico e doxorrubicina por ligação hidrazona foram produzidos em tampão PBS pH 7,4, contendo 22 μg DOX/mg, tamanho médio de 100 nm e um índice de polidispersidade de cerca de 0,5. A conjugação por ligação amida foi efetuada em DMSO, o que conduziu a um conteúdo de doxorrubicina de 29 μg DOX/mg, tamanho médio de 70 nm e um índice de polidispersidade de cerca de 0,45. Os estudos de libertação indicam uma libertação satisfatória a pH 5,0 (pH dos lissossomas), contudo a pH 7,4 (pH extracelular) verificou-se também alguma libertação. A estabilização de 𝘺-Fe2O3 nos nanogéis, designados de nanomagnetogéis, levou à estabilização de 0,6 a 0,9 mM de 𝘺-Fe2O3. Os ensaios de citotoxicidade foram realizados com a linha celular A549, e o conjugado de ácido hialurónico por ligação amida apresentou uma atuação rápida e levou a um decréscimo na viabilidade celular. Em suma, foram produzidos nanogéis de ácido hialurónico e doxorrubicina usando uma ligação sensível ao pH, hidrazona, e ligação amida. Os nanogéis mostraram características interessantes para sistemas de entrega de fármacos, permitindo assim terapias mais eficientes, apesar de ainda serem necessárias algumas otimizações. A incorporação de 𝘺-Fe2O3 foi conseguida nos nanogéis, o que pode permitir a sua deteção por técnicas de imagem para diagnóstico ou para avaliação da terapêutica, ao mesmo tempo que se faz a libertação controlada do fármaco.
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Su, Fang-Yi, and 蘇芳儀. "Recovery of Hyaluronic Acid by Ultrafiltration." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/99798436545611204458.
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Chen, Yu-Ru, and 陳俞如. "Hyaluronic acid-polylactic acid copolymers as carriers for tumor therapy." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/66399566281997631240.
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碩士國立中興大學
化學系所
99
In this research, we synthesis of biodegradable and biocompatible hyaluronic acid-poly lactic acid conjugate as carrier for drug delivery to reduce the cytotoxcity and prolonged circulation in blood. The HA molecular weight was controlled by acid and microwave which can degrade HA into small fragments (Mw~ 3 K to 220 K), the molecular weight of HA were determined by gel filtration chromatography (GFC). Than quantum dots are conjugate on the hyaluronic acid. Through the cell image by quantum dots, and the distribution in vitro and in vivo to investigate the different molecular weight HA conjugate to poly lactic acid affect the bio-distribution and bio-function. Furthermore, HA could bind to the tumor cell which CD44 receptor over-expressed for tumor therapy.
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Wu, Fong-Chang, and 吳逢倉. "Hyaluronic Acid Production by Applying Microbial Fermentation." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/95402254757221459993.
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碩士長庚大學
生化與生醫工程研究所
93
This study develops a process for producing hyaluronic acid by microbial fermentation. Glucose, arginine, uracil, cysteine and histidine were found to improve the production of hyaluronic acid by Streptococcus zooepidemicus. An optimized medium was designed by response surface methodology analysis and the medium composition should be basic medium supplemented with 56 g/L glucose, 80 mg/L arginine, 56 mg/L uracil, 30 mg/L cysteine and 13mg/L histidine. The best operating parameters during batch fermentation should be at 37℃, pH 7.0, agitation rate 600 rpm and aeration rate 1 VVM, which gave hyaluronic acid yield of 5.4 g/L. In addition, high agitation rate（900 rpm）, mild pH value（pH＝6.7-7.0） and temperature（34-37℃）favored the formation of higher molecular weight hyaluronic acid. However, in the presence of high glucose concentration, oxygen transfer limitation and repression effect were observed. To solve this problem, a fed-batch fermentation process was designed and led to a substantial increase of the yield to 7.2 g/L. Besides, molasses was also demonstrated in this research to be a potential cheap carbon source to replace glucose.
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HSIANG-LAN, LIU, and 劉湘蘭. "The Preparation and Application of Hyaluronic Acid." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/12656472808603007737.
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碩士大葉大學
生物產業科技學系碩士在職專班
95
Hyaluronic acid is a high-molecular-weight linear polysaccharide composed of repeating disaccharide units of D-glucuronic acid and N-acetylglucosamine linkaged by β(1-3) and β(1-4) glycosidic bonds. The average molecular weight is typically in the range 105 to 107 dalton. Hyaluronic acid is obtained usually from the solvent extraction of animal soft tissues that posses problems of quality and source instability. Traditionally, most hyaluronic acid has been produced by extraction of cock''s combs, although in recent years, attention has turned to Streptococcus fermentation due to the complexity of animal tissue sources and the consideration of production costs. The most important biological functions of hyaluronic acid. Ubiquitously distributed in the extracellular matrix and biological fluid .It provide cellular support , regulate cell adhesion , cell aggregation migration , proliferation and differentiation etc. Hyaluronic acid solution has special viscoelastic properties and can supply many physical functions in animal body, such as protection, lubrication and support. Because of hyaluronic acid special biocompatibility, extraordinary rheological property and moister-holding function, it has been used as biomedical, medical, health care food, cosmetic industry and else relevance field.
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Yang, Chia-Ming, and 楊家銘. "Study on High Concentration Hyaluronic Acid Fermentation." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/45397477636847316499.
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碩士國立成功大學
化學工程學系碩博士班
96
High concentration hyaluronic acid (HA) fermentation by Streptococcus zooepidemicus ATCC 39920 has been investigated. It was found that, mixing time was an important parameter in this high viscosity system caused by increasing cell density and hyaluronic acid yield. It was suggested that mixing time should be controlled within 30 seconds to maintain HA productivity.
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Chang, Wei-Han, and 張唯涵. "Remodel – Natural Hyaluronic Acid Skin Care Product." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/3h2kgb.
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碩士國立臺灣大學
企業管理碩士專班
105
Remodel, is a company who delicate on the medical and biotech materials invention for years. Our core technology is across all the biotech scope and one of our products is Natural Hyaluronic Acid (RM-NHA127) which can be used in the medical material and cosmetics. We are using the bacteriostatic characteristic of Hyaluronic Acid. Through our technology and formula, Hyaluronic Acid can be extended its bioactivity and antimicrobial continuously without any preservation method or additives. Withholding unique technology on Hyaluronic Acid, Remodel will be able to provide the public the most natural, toxic free, and low allergy skin care product at a competitive price. That will cater to the needs of customers who are conscious users who have awareness of risk of being exposed to chemicals. This study analyzes and attempts to distinguish Remodel from its competitors from their business model, competitive advantage, and other factors. This study also summarizes how value proposition can help to compete in such keen competitions in Taiwan.
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Wibowo, David, and 葉濤欣. "Antibacterial Cellulose Fibers for Hyaluronic Acid Recovery." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/63869851046055825701.
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碩士國立臺灣科技大學
化學工程系
96
This thesis was motivated by the practical need to develop a scalable and cost-effective separation method to recover hyaluronic acid (HA), a commercially valuable medical biopolymer, from bacterial culture broth. This challenge can potentially be addressed by taking advantage of the polyanionic character of HA. Through the electrostatic interaction with cationic matrix, HA is expected to be recovered. In this thesis quaternary ammonium modified cellulose fibers were used to recover HA directly from the Bacillus subtilis culture. At the first stage of the studies, two variant of cellulose fibers were prepared by grafting different type of the antibacterial quaternary ammonium compound (QAC). Silane (3-(trimethoxysilyl)-propyldimethyloctadecyl ammonium chloride) and choline based ionic liquid analogue (sodium hydroxide and 2–chloroethyltrimethylammonium chloride based deep eutectic solvent) were used to quaternize the cellulose fibers surface. Results from elementary analysis, grafting ratio determination by weight measurement and Fourier transform infrared spectroscopy demonstrated that either silane or choline has been successfully grafted onto the surface of cellulose fibers after the chemical modification. Prior to the adsorption studies, the antibacterial assessments were performed. It was shown that both silane modified cellulose fibers (SMC) and choline modified cellulose fibers (CMC) have antibacterial activity against E. coli and B. subtilis, with the former had better activity due to the presence of long alkyl chain on the quaternary ammonium groups of SMC. The antibacterial activity for E. coli is higher than that for B. subtilis due to the difference in cell wall structures. The feasibility of the antibacterial cellulose fibers on HA adsorption was then explored. Adsorption of HA onto the modified cellulose fibers was carried out at different pHs (3–8) and temperatures (277, 291, 310 K). Adsorption isotherms followed the Langmuir isotherm model and the adsorption was thermodynamically favorable. The maximum adsorption capacity for SMC and CMC was found to be 183.67 mg/g (at pH 4, 310 K) and 351.32 mg/g (at pH 7, 277 K), respectively. The adsorbed HA on SMC could be effectively desorbed as much as 90.11% by 1 N NaCl at pH 7 while changing the pH to 3 was effective to desorb 36.50% of HA from CMC. The adsorption capacity of SMC decreased to 49% after 3 cycles, whereas the capacity of CMC decreased to 89%. Finally, the capability of the modified cellulose fibers on the recovery of HA directly from B. subtilis culture was demonstrated. SMC was used in this process rather than CMC due to its high desorption efficiency. The antibacterial effect of SMC caused by its strong hydrophobic character also good for HA recovery. One gram of SMC was able to adsorb 14.94 mg of HA directly from the B. subtilis culture. The adsorption capacity of SMC used in this recovery process was much less than in the equilibrium adsorption studies due to the competition adsorption occurred in the culture broth.
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Ming, Liu Yue, and 劉岳明. "Hyaluronic acid production by immobilized Streptococcus zooepidemicus." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/78710497450649558641.
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碩士長庚大學
生化與生醫工程研究所
94
Abstract The purpose of this research is to immobilize Streptococcus zooepidemicus by adsorption onto four different kinds of support, diatomaceous earth FW-14, Celite 560, Moso bamboo charcoal, and Chitopearl 3520, for production of hyaluronic acid. From results of repeated batch fermentation and one-way ANOVA analysis, Moso bamboo charcoal demonstrates the best operation stability in each repeated batch cycle and was chosen for further bioreactor study. The best immobilization condition is with 1 g/l chitosan-treated Moso bamboo charcoal, 5 g/l initial biomass loading, and 0.5 ml/min circulation velocity. The cell immobilization efficiency is more than 80% in this case. The best batch fermentation condition is 37 ℃, pH 7.0, 300 rpm, and 10 g/l initial glucose concentration. This system can produce 1.47 g/l hyaluronic acid and the productivity and glucose yield are 4.58 g/h/l and 0.14 g/g, respectively. Repeated batch fermentation experiments showed that immobilized cells could be reused for up to six times and hyaluronic acid concentration can be maintained at 1.2 g/l.
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Hsiao, Chih-Chun, and 蕭至君. "Production of hyaluronic acid from recombinant Escherichia coli." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/25009982639030748454.
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Chen, Ya-Wen, and 鄭雅文. "Expression of the Hyaluronic Acid Synthase Protein of." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/25518514744227812885.
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碩士國立交通大學
生化工程研究所
93
Hyaluronic acid exists in many mammalian connective tissues such as joints, vitreous bodies, umbilical cords, cartilages, skins, and combs of fowls as a constituent; it fulfills important functions such as flexibility and structure maintenance of tissues. Hyaluronic acid is a polymer made of repeating units of glucuronic acid and N-acetyl-glucosamine bound by alternating β-1,3 and β-1,4 bonds. Its molecular weight is in the range of 10 kD~ 1000 kD. It has a wide variety of uses in cosmetics, medicine for wounds, eye drops, and medicines for ophthalmic surgery and arthritis. Currently, the production of HA comes from extraction animal tissue or fermentation of HA-producing pathogens. Both have issues concerning health and safety. Introduction of molecular recombinant DNA technique to the production of HA is a new trend to solve the problems. In this study, I have successfully constructed recombinant plasmid expressing hasA encoding protein of Streptococcus zooepidemicus in E. coli. The recombinant protein has contained in-vivo-expressing tag of either HA (influenzae hemagglutinin) or HA-HIS (influenzae hemagglutinin-polyhistidine). Recombinant proteins of HAS fusing with HA-HIS tag can be detected in the pellet fraction of the E. coli expression system by Western blotting analysis. Meanwhile, Purification using nickel column of the recombinant protein of HAS with HIS tag was also achieved.
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Chen, Jia-Ling, and 陳嘉凌. "Fermentation Strategy for Producing Hyaluronic Acid by Streptococcus." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/33684970762235906725.
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碩士國立高雄應用科技大學
化學工程系碩士班
94
The effect of specific growth rate and temperature on the production of hyaluronic acid by Streptococcus zooepidemicus ATCC39920 was investigated. The optimal ratio of glucose to yeast extract for hyaluronic acid production is 2:1, which was used as basal composition of fermentation medium. The specific productivity of hyaluronic acid increased as the decrease in temperature during the range from 30 to 37°C. The fed-bath data showed that the production of hyaluronic acid was affected by temperature rather than the change in specific growth rate. Accordingly, batch culture was suggested to be the optimal fermentation mode for producing hyaluronic acid.
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LIU, ZHONG-RUI, and 劉中瑞. "Study of collagen/hyaluronic acid/tricalcium phosphate composites." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/8pdt6e.
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碩士國立臺北科技大學
化學工程研究所
100
In this study, composite restoration materials (CHTP) made of type I collagen, hyaluronic acid (HA) and tricalcium phosphate (β-TCP) were prepared and crosslinked with the natural crosslinking agent, oligomeric proanthocyanidins (OPCs). The crosslinking property was evaluated. The mechanical strength, swelling ratio and in vitro degradation rate of the optimally crosslinked CHTP composite were investigated. In vitro tests were carried out to evaluate the biocompatibility using MG-63 cell line. Results indicated that the crosslinked composite using 5% OPCs solution (CHTP-5%) had high swelling ratio (420%) and mechanical strength (40 kPa), and remained more than 60% weight after 30 days in vitro degradation test. The results of in vitro tests showed that CHTP-5% would promote the proliferation of MG-63 cell. The results of material analyses and in-vitro tests showed that CHTP-5% composite is of great potential to serve as a useful bone restoration material.