中文摘要：

目的：制备水飞蓟宾缓释纳米球并考察其制备影响因素。方法：以乳酸羟基乙酸共聚物为载体材料，采用沉淀法制备水飞蓟宾纳米球；通过激光粒径测定仪测定纳米球的粒径及其分布、透射电镜观察纳米球的形态；以载药量、包封率、粒径和药物利用率等为指标，通过单因素试验考察了处方因素和工艺因素对纳米球质量的影响，并初步确定了各因素的取值范围。结果：制备的纳米球外观圆整。在一定范围内，随聚乳酸用量的增加，纳米球的载药量和包封率均增加；随投药量的增加，纳米球的实际载药量和粒径显著增加，但包封率和药物利用率均减小；丙酮体积在1～5ml和7～1（ImI范围内，随体积的增加载药量和药物利用率显著增加；水相体积由10ml增加到100ml时，载药量由0．88％提高到7．45％，药物利用率由8．16％提高到77．120／oo；随着PluronicF68浓度继续增加，纳米球的载药量和药物利用率显著提高，当浓度为5．0％时，纳米球的载药量和药物利用率最高；pH在6．0～7．O范围内，pH升高，对药物的载药量、包封率和药物利用率均有正效应；搅拌速度越快，制得的纳米球粒径就越小，有机溶剂越易挥尽。以550r·min^-1转速较适宜。结论：沉淀法是基于界面沉积原理进行药物的包裹，适用于某些脂溶性药物纳米球的制备。

英文摘要：

OBJECTIVE To prepare the sustained-release nanospheres of silybin and investigate the influential factors. METHODS The nanospheres of silybin were prepared with PLGA as carrier by a precipitation method. Particle size was detected using nanometer particle size and Zeta potential analyzer, morphology of nanospheres was observed using transmission elec- tron microscope. The effects of formula factors and process factors on drug loading, entrapment efficiency, drug availability and mean diameter were investigated by single-factor experiment, and value range of factors were determined initially. RESULTS The morphology of nanospheres was round. The drug loading and entrapment efficiency were increased with increasing the concentration of PLGA in organic phase. The drug loading and mean diameter were increased significantly, but entrapment efficiency and drug availability were decreased with increasing ratio of drug to carrier. The drug availability was increased dramatically with increasing the volume of organic phase in the range of lm1-5 ml and 7 ml-10 ml, while the volume of water was increased from 10 ml to 100 ml, the drug loading was raised from 0. 88% to 7. 45%, and drug availability was raised from 8. 16% to 77. 12%. The drug loading and drug availability of nanospheres were increased with increasing the concentration of Pluronic F68 in water phase, while the concentration was 5.0%, both drug loading and drug availability of nanospheres were the best. Effects of pH values （6. 0-7. 0） on drug loading, entrapment efficiency and drug availability were positive. The mean size of nanospheres was decreased with increasing the stirring rate, and acetone was also evaporated easily, 550 r·min^-1 was selected as a suitable stirring rate. CONCLUSION The precipitation method is based on the principle of interface deposition, it is suitable to prepare polymer nanospheres loaded with some water-insoluble drugs.