中文摘要：

目的：制备稳定性高、粒径小的脑源性神经营养因子（BDNF）缓释注射纳米粒，并评价其释药过程。方法：采用乳酸-羟基乙酸共聚物（PLGA）为载体材料，复乳化溶剂挥干法制备载有BDNF的PLGA纳米粒。优化纳米粒处方和制备工艺，观察纳米粒的形态、大小和粒径分布，评价其回收率、精密度、重复性、包封率以及体外释药特性。结果：优选处方选择理论载药量1％、聚合物浓度3．3mg／ml、超声时间为40s，甘露醇为支架剂。BDNF纳米粒呈圆形，大小均匀，平均粒径为156．7nm。制备的纳米粒回收率、精密度、重复性和包封率较高，缓慢溶蚀释放为其主释药过程，时间达30d。结论：成功制备的BDNF缓释注射纳米粒具有稳定性好、包封率高的特点。

英文摘要：

Objective：To prepare stable, small-sized injectable sustained-release nanoparticles harboring brain-derived neurotrophic factor （BDNF） and to evaluate its drug releasing process. Methods： The nanoparticles were prepared using poly（D, Llaetic-co-glycolic acid） （PLGA） as the carrier by w/o/w double emulslon-solvent evaporation method. The formula and technique were optimized ; the shape, size and the distribution of the diameters of the particles were observed ; and recovery rate, precision, repeatability, encapsulation efficiency, and drug releasing characteristics were assessed. Results： With the optimized formula, the drug loading rate was 1 % ,the polymer concentration was 3.3 mg/ml, and the ultrasound time was 40 s; mannitol was used as the supporting agent. BDNF nanoparticles were round, homogenous in size, with a mean diameter of 156.7 nm. The prepared particles had high recovery rate, precision, repeatability, and encapsulation efficiency. The drug release was characterized by slow corrosion and the process lasted for 30 days. Conclusion.. We have successfully prepared slow-release nanoparticles harboring BD- NF,which are stable and have high encapsulation efficiency.