生物降解型卡铂微球体外释放过程及其机理研究

目的 探寻卡铂-PIGA（聚乳酸-羟基乙酸）缓释微球体外降解过程及其机制。方法将通过丙酮矿物油乳化溶剂挥发法制备的卡铂-PIGA缓释微球放置磷酸缓冲液中，取不同时间点进行扫描电镜观察微球在体外降解过程中的超微结构变化。结果所制备的微球降解前呈规则圆形，表面光滑。扫描电镜下不同时间点微球表面出现不同的情况。其外壳首先出现“脱皮”现象，然后出现明显的溶胀并伴有“孔洞”形成。包封在微球内部的药物晶体通过溶渗作用逐渐释放。结论卡铂-PIGA缓释微球具有一定的缓控能力。其包封的卡铂药物晶体是通过“孔洞”溶渗作用逐渐释放出微球的。

An in vitro study on the morphology of biodegradable carboplatin-loaded PLG amicrospheres

Objective To seek a way to prepare carboplatin-loaded PLGA microspheres and to study its release mechanism in vitro. Methods The microspheres prepared by the water-in-oil-in-water-emulsion-based solvent evaporation method were added into PBS buffer solution and their release and morphology were studied under a scanning electron microscopy at different time points. Results The obtained microspheres were well spherical with smooth surface. Observed under the scanning electron microscopy,the shell of microspheres changed with the time, which peeled off firstly, and then lyzed with some holes appearing, leading to the gradual release of the enveloped carboplatin by osmosis. Conclusion Carboplatin-loaded PLGA microspheres have an ability of controlled release for drugs. The releasing process in vitro is accomplished by the effects of lysis and osmosis through the holes.