PEG-I-dC_(16)酸敏释药胶束的制备与体外评价

Preparation of Acid-sensitive Drug Release PEG-I-d C_(16) Micelles and in vitro Evaluation

目的构建聚乙二醇-亚胺键-棕榈酸酯(PEG-I-d C16)酸敏释药纳米胶束,并考察载阿霉素胶束在体外的抗肿瘤活性及药物被细胞摄取的情况。方法通过透析法制备载阿霉素胶束,采用紫外法测定胶束的载药量和包封率,并用粒度仪测定其粒径和Zeta电位。进一步采用MTT法测定其体外抗肿瘤活性,用流式细胞仪测定其细胞摄取量,并用激光共聚焦观察细胞核内的药物蓄积量。结果分子量为2000的PEG胶束的载药量和包封率分别为(12.7±1.1)%和(49.8±2.2)%,平均粒径为(72.3±2.5)nm。酸敏释药胶束的细胞药物摄取量与细胞毒性均高于非酸敏释药胶束,且在细胞核的药物蓄积量也比非酸敏胶束高,差异均具有统计学意义(P<0.05)。结论 PEG-I-d C16酸敏释药胶束可增加细胞或细胞核对阿霉素的摄取量,提高其体外抗肿瘤效果,为开发肿瘤靶向给药系统提供了研究基础。

Objective To investigate the advantages of acid sensitive micelles on in vitro anti-tumor activity and cellular uptake by construction of polyethylene glycol-imine-palmitate and doxorubicin-loaded micelle. Methods Doxorubicin was encapsulated in the micelles by using membrane dialysis method. The determination of micelle drug-loading capacity and encapsulation efficiency were studied by UV. Zeta potential and particle size was measured by a particle size analyzer. Anti-tumor activity in vitro was examined by MTT assay, and cell uptake was measured by flow cytometry. The drug in the nucleus was observed by laser confocal microscopy. Results Drug-loading capacity and encapsulation efficiency of Micelle（PEG molecular weight 2 000） was（12.7±1.1） % and（49.8±2.2） %, respectively. The average particle size was（72.3±2.5） nm. The in vitro cytotoxicity and intracellular drug uptake of acid-sensitive micelles were higher than that of non-acidsensitive micelles in A549 cells and Hep G2 cells. Correspondingly, more drugs was observed in Hep G2 nuclear than nonacid-sensitive micelles. Conclusions The acid-sensitive micelles could increase the cell or cell nuclei uptake of drug, and improve the effects of antitumor in vitro. It provides a research foundation for cancer targeted drug delivery system.