BCNU-PLGA缓释可降解微球的制备与特征

Preparation and characteristics of BCNU-loaded biodegradable microspheres

目的选择不同分子量及成份的聚乳酸/羟基乙酸(PLGA)共聚物材料,考察粒径、表面形态、包封率、二氯甲烷残留量及体外释放的特点。方法以溶剂挥发法制备卡氮芥-聚乳酸/羟基乙酸(BCNU-PLGA)缓释微球,以扫描电子显微镜观察微球表面形态、测定微球直径,以高效液相色谱法测定微球包封率和体外药物释放,气相色谱法进行二氯甲烷残留量分析。结果BCNU-PLGA缓释微球粒径随分子量升高而增大,表面呈球形,包封率达90%,二氯甲烷残留量6．85‰,体外释放时间达3周。结论溶剂挥发法制备的BCNU-PLGA缓释微球释药可达3周以上,并维持较高药物浓度,为颅内缓释化疗提供新的方法。

Objective To prepare sustained carmustine （BCNU） release microspheres with poly （lactic-co-glycolic acid） （PLGA） polymer materials of different molecular weights and compositions, and to observe and determine their diameter, shape, encapsulation efficiency, residual methylene chloride content and in vitro release characteristics. Methods BCNU-loaded PLGA microspheres were made by solvent evaporation method. The morphology was observed and the diameter was determined by scanning electron microscope; the encapsulation efficiency and in vitro release mode were explored by high performance liquid chromatography （HPLC）; the residual methylene chloride content was determiined by gas chromatography （GC）. Results Diameters were increased with the adding of molecular weight. In vitro release period of the BCNU-PLGA polymer was prolonged to 3 weeks. Encapsulation efficiency reached 90% and residual methylene chloride content was 6.85%0. Conclusion BCNU-PLGA biodegradable microspheres can maintain high concentration during the release of over 3 weeks, which provides a new way for intracerebral interstitial chemotherapy.