【作者】 陈涛；

【导师】 姚康德；

【作者基本信息】 天津大学 ， 材料学， 2005， 硕士

【摘要】 可注射原位成型支架,在注射前为溶胶,可负载活性细胞、治疗药物和生长因子等。当注射到指定部位后,在温度、pH值、离子强度或其它条件作用下,在注射部位发生相转变而凝胶化。此组成物有易于操作、塑型方便和手术创伤小等优点,可用作药物载体、填充材料、组织替代物和临时组织支架,应用前景广阔。本实验对壳聚糖进行改性,制备了水溶性的盐酸化壳聚糖(CH),通过对CH、β-甘油磷酸二钠(GP)和β-磷酸三钙(TCP)进行复合制备了可注射性生物复合材料。pH值、温度和组成物配比的调节,组成物在生理环境下发生相转变而凝胶化。组成物含水量高,结构多孔,比较适合细胞的黏附与增殖。兔关节软骨缺损处植入实验结果表明,该材料的生物相容性良好。以壳聚糖、明胶为载药基质,以中药淫羊藿为模型药物,通过乳化交联的方法制备淫羊藿壳聚糖/明胶微球,考察了微球的理化特性,建立持续流动的释放系统,检测了微球的体外释放特性和影响因素。微球的理化特性受工艺条件如搅拌速度、乳化剂用量和交联剂用量等因素影响,微球的体外释放速率与微球的粒径和交联度负相关,与载药量正相关。实验的结果表明,由CH、GP和TCP构建的复合材料组成物是一种很有潜力的、有效的骨和软骨组织工程支架材料。壳聚糖、明胶可作为缓释微球的载体基质,微球制备工艺简单稳定,释放速率可控,淫羊藿壳聚糖/明胶微球是一种良好的药物释放体系。更多还原

【Abstract】 An injectable in-situ forming scaffold can be maintained sol state before beinginjected to deliver living cells, therapeutic agents and growth factors, etc. Thesesystems can turn into gels in situ by regulating conditions, e.g. temperature, pH, andionic strength. These compositions have many advantages, e.g. ease of operation andapplication, and little surgery wound. They can be used as drug delivery systems,filling materials, tissue substitutes and temporary scaffolds. Therefore, injectable in-situ forming compositions are believed to have extensive applications in the future.In this paper, the water-soluble chitosan hydrochloride was synthesized and itsmolecular structure was studied. Injectable compositions based on chitosanhydrochloride, β-glycerophosphate and β-tricalcium phosphate were prepared. Byadjusting pH, temperature and ratio of components, the compositions sol could turninto gel in physiological environment. The compositions had high water contents andporous structure, which was fit of cell adhering and proliferation.Icariin/Chitosan/Gelatin microspheres were achieved by emulsification and cross-linking methods. Physical and chemical characteristics were detected. A continualflowing system was used to determine releasing characteristics of microspheres andinfluencing factors. The physical and chemical characteristics of microspheres wereinfluenced by process conditions e.g. rate of mixing round, quantity of emulsificationand cross-linking agents. The in vitro release rate was negatively correlated withgranule diameters and crossing-linking extent, and positively correlated with drugcontents. The injectable compositions exhibit good biocompatibility and are a potentialscaffold in bone and cartilage tissue engineering. It is feasible for chitosan and gelatinmicrospheres to act as carriers of slow release of Chinese herber. Preparation processis simple and stable. The release rate of drug from microspheres is adjustable.更多还原