中文摘要：

背景：近年来,两亲性聚合物胶束作为难溶性药物载体和叶酸介导的肿瘤细胞靶向给药系统在药剂学研究领域受到极大的关注。目的：制备包载9-硝基喜树碱的叶酸聚合物胶束并进行理化表征及体外药效评价。方法：采用薄膜-水化法制得载药胶束,利用激光粒度分析仪检测胶束粒径大小,反相高效液相层析法检测载药量,透析法进行体外释放试验;利用肿瘤细胞摄取及体外生长抑制试验,对叶酸聚合物胶束作体外药效评价。结果与结论：制得的9-硝基喜树碱叶酸聚合物胶束粒径为24～26nm,载药量为3.24%,24h累积释放百分率约90%。叶酸修饰的聚合物胶束对肿瘤细胞的亲和性及抗肿瘤活性显著高于普通胶束。提示叶酸修饰的聚合物胶束可为难溶性药物提供一种具有良好应用前景的肿瘤主动靶向纳米载药系统。

英文摘要：

BACKGROUND：Recently,the increasing attention has been focused on amphiphilic polymer micelles as carriers for poorly soluble drugs and folate-mediated tumor targeted drug delivery system in the field of pharmaceutics.OBJECTIVE：To prepare 9-nitro-camptothecin（9-NC）-loaded folate-conjugated polymer micelles and investigate its characterization and antituomor activity in vitro.METHODS：The 9-NC-loaded folate-conjugated polymer micelles were prepared by film-hydration method;micelles size and drug loading capacity were determined by laser particle size analyzer and reversed-phase high-performance liquid chromatography respectively.The dialysis method was used in vitro release study.Pharmacodynamic evaluation in vitro was performed using cellular uptake and cell growth inhibition tests.RESULTS AND CONCLUSION：The diameter of the formulated 9-NC-loaded folate-conjugated micelles was about 24-26 nm.The encapsulation efficiency and drug loading capacity were 95.7% and 3.24% respectively.And the accumulative release percentage in 24 hours of drug-loaded micelles was about 90%.Besides,the folate-conjugated micelles had higher binding affinity with tumor cells and significantly stronger antitumor activity in vitro than normal micelles.The results indicated that the folate-conjugated micelles can provide a type of tumor-targeted nano drug delivery system with good prospect for insoluble drugs.