缓释药物载体明胶微球酸水解影响因素的研究

采用乳化交联法制备明胶微球(GMS),以柠檬酸为水解促进剂,利用双缩脲法研究了反应时间、温度及pH值对GMS及明胶水解程度的影响。结果表明,GMS水解的速率随反应时间的增长或温度的增高而加快,随水解pH值的增高而减慢;同等条件下,相比于GMS,明胶的水解较为彻底,在酸性环境中不如GMS稳定;GMS水解过程的SEM图进一步表明,在酸液的作用下,GMS溶胀后表面光滑致密,药物只能通过骨架缓慢扩散或交联结构的水解而缓慢释放,避免了药物突释。优化反应条件为:在水解时间3 h,温度80℃,pH值2时,GMS的水解较为彻底。

Study on influence factor of acid degradation of gelatin-microsphere used as drug carrier

Gelatin-microsphere(GMS) was prepared by emulsion chemical-crossline technique.With the hydrolytic agent of citric acid,the effect of different hydrolyzed time,temperature and pH on the gelatin hydrolyzing degree and GMS was studied by the method of biuret.The result shows that increasing time temperature and pH values could accelerate the hydrolytic rate of GMS.At the same condition,the hydrolysis of gelatin was more completely compared with GMS,and it was more unstably in the acid environment.The SEM of gelatin hydrolysis indict in the acid environment,the surface of GMS was smooth and compact after swelling,the drug could only release slowly by skeleton diffusion or the hydrolytic of crosslinking structure.The optimum conditions were as follows:the time 3 h,temperature 80 ℃ and pH 2.