乳化-溶剂挥发法制备左旋多巴微囊

目的优选乳化-溶剂挥发法制备左旋多巴微囊的工艺。方法以乙基纤维素（EC）为囊材，以微囊的包封率、载药量、累积溶出百分率为指标，采用正交试验优选左旋多巴微囊乳化-溶剂挥发法制备工艺条件，并对优化工艺所得微囊进行质量检查。结果优选出的制备工艺为：囊材溶于二氯甲烷的比例为8％，囊材与药量比例为1：1，EC（10mPa／s）与EC（20mPa／s）的比例为1：3，验证试验表明优化工艺所制左旋多巴微囊微囊平均包封率为92．98％，载药量为46．74％，24h累积溶出百分率为81．07％。微囊外观圆整且无粘连现象，微囊的粒径范围为10-50μm，体外具有明显的缓释效果。结论该工艺操作简便，工艺条件稳定、合理、可行。

The preparation of Levodopa Microcapsules by the method of Emulsion-Solvent Evaporation

Objective To optimize the program of Levodopa （LD） by the method of emulsion-solvent evaporation. Methods The drug-loading rate, entrapment rate and the accumulated release ratio were selected as indexes; the preparing of LD mierocapsules was optimized by the orthogonal design. The quality of LD microcapsules, which were prepared by the optimized program, was checked. Results The optimized program of LD microcapsules was as following： the weight rate of EC and LD is 1 ： 1, the weight rate of EC （10 mPa/s） ： EC （20 mPa/s） is 1 ： 3, the concentration of EC is 8%. According to the result of verification test, the drug-loading rate of optimized LD microcapsules was 46.74% and the entrapment rate was 92.98%, the accumulated release ratio was 81.07% at 24 h. The appearance of LD microcapsules is rounding and is kept from sticking, the range of particle size of LD microcapsules is 10-50 μm. Microcapsules have a sustained release character in vitro. Conclusion This method is easy. The condition of preparation is stable, reasonable and feasible.