界面聚合法制备pH响应型药物微胶囊及其性能研究

Study on preparation of pH-sensitive drug-loaded microcapsules by interfacial polymerization and its characterization

采用界面聚合法,以聚乙烯醇为保护胶体,曲拉通X-100为乳化剂,超支化聚L-赖氨酸和对苯二甲酰氯为壁材,咖啡因为模型药物,制备了pH响应型药物微胶囊。利用正交实验研究了高速剪切速度,剪切时间,保护胶体用量,乳化剂用量对微胶囊包封率的影响。表征了微胶囊的结构、形貌、粒径大小及其分布,研究了微胶囊在不同pH的缓冲溶液中的药物释放行为。结果表明:所制备微胶囊的壁材和芯材分别由超支化聚L-赖氨酸与对苯二甲酰氯反应产物和咖啡因组成;所得微胶囊呈规则的球形,具有较光滑的表面;微胶囊的粒径分布集中,并呈正态分布。微胶囊的药物释放行为对不同pH的缓冲溶液表现出明显的依赖性。

The pH-sensitive microcapsules were prepared by interracial polymerization, in which caffeine was used as a model drug and hyperbranched poly L-lysine（HBPL） and terephthaloyl chloride as wall-forming materials. Using statistical analysis of orthogonal experiment, the effects of the emulsifying rate, emulsifying time, protective colloid content and content of e- mulsifier on the encapsulation efficiency of the microcapsules were discussed. The structure and particle size distribution and surface of microcapsules were characterized. The release be- haviours of caffeine in different phosphate buffered saline（PBS） pH were investigated system- atically. As a result, caffeine was successfully encapsulated in the wall-forming materials. The resultant microcapsules had the narrow particle size distribution and smooth surface. These drug-loaded microcapsules have shown sensitivity to pH value.