利培酮长效注射微球的制备及体外释放的研究

目的：制备利培酮长效注射微球并考察其体外释放行为。方法：使用乳酸-羟基乙酸共聚物（PLGA）为材料，采用乳化-溶剂挥发法制备利培酮微球，观察微球的形态及粒径，测定微球的载药量和包封率，考察微球的体外释放情况。结果：利培酮微球表面圆整，粒径集中在40～80μm之间。微球的包封率较高，达到80％以上，以低分子量PLGA（50：50）制备的微球，体外突释很高达到40％以上；以高分子量PLGA（75：25）制备的微球，在高载药量时突释较小，可持续释放达3周以上。结论：以高分子量PLGA制备的高载药量的利培酮微球，体外突释较小可缓释达3周以上。

Studies on Preparation and Release in Vitro of Risperidone Loaded Long-acting Injectable Microspheres

Objective： To study the preparation of injectable long-acting risperidone microspheres and release in vitro. Method： The risperidone microspheres loading ploy （lactic-co-glyeolide acid） （PLGA） was prepared by emulsion-solvent evaporation method. The morphous and particle diameter of microspheres were observed and the drug lording and entrapment efficiency of microspheres were determined to study releasing in vitro. Result： Microspheres with good shape and dispersive quality were prepared. Particle diameter of microspheres was at 40 - 80 μm. The drug entrapment efficiency was more than 80%. The burst releasing in vitro of microspheres pre- pared by low molecular PLGA（50：50） was more than 40%. The burst releasing in vitro of microspheres with high drug loading prepared by high PLGA （75：25） molecular was low, and the releasing in vitro sustained three weeks. Conclusion： The burst releasing in vitro of rlsperidone microspheres prepared by using high molecular PLGA with high drug loading is low and the risperidone mierospheres keep three weeks continuous releasing.