改良自乳化溶剂扩散法制备MePEG-PLA纳米粒对成骨细胞的毒性*

两亲性嵌段聚合物由于其较强的载药能力强、纳米级大小、血液中长循环等优点在载药系统中得到广泛的应用。 目的：评估改良自乳化溶剂扩散法制备的甲氧基封端的聚乙二醇-聚乳酸 (MePEG-PLA)纳米粒对人骨肉瘤细胞MG63的毒性。 方法：通过改良自乳化溶剂扩散法制备MePEG-PLA纳米粒，MTS法测定纳米粒培养1，2，3 d后对MG63的毒性。激光粒度分析仪测定纳米颗粒的粒径大小、粒径分布及Zeta电位；透射电镜表征纳米胶束外观形态；酶标仪检测培养1，2，3 d细胞吸光度值。 结果与结论：MePEG-PLA纳米粒的平均粒径为25.7 nm，分布均匀，呈球形，Zeta电位为-8.06 mV，MePEG-PLA毒性为 0级。提示改良自乳化溶剂扩散法制备纳米粒简单易行，制备的纳米粒无毒，具有良好的应用前景。

Cytotoxicity effect of MePEG-PLA nanoparticles prepared by modified self-emulsion solvent diffusion technique on osteoblasts in vitro

BACKGROUND: Amphiphilic block copolymers have been widely applied in the drug delivery system because of the high capacity of drug carriers, nanoparticles and long circulation time. OBJECTIVE: To evaluate the cytotoxicity effect of MePEG-PLA nanoparticles prepared by modified self-emulsion solvent diffusion technique on MG63 in vitro. METHODS: MePEG-PLA nanoparticles were prepared by modified self-emulsion solvent diffusion technique. The cytotoxicity effect of MePEG-PLA nanoparticles on MG63 was detected using MTS assay at days 1, 2, 3. Particles size, polydispersity index and Zeta electric potential were measured by laser particle size analzer. The morphology of MePEG-PLA nanoparticles were observed by transmission electron microscope. Absorbance values at days 1, 2, 3 were detected by microplate reader. RESULTS AND CONCLUSION: MePEG-PLA nanoparticles had a regular spherical shape with the mean diameter of 25.7 nm and scattered evenly. The Zeta potential was -8.06 mV. The cytotoxicity grade of MePEG-PLA nanoparticles was 0. The results indicate that MePEG-PLA nanoparticles prepared easily by modified self-emulsion solvent diffusion technique are nontoxic to the MG63 and have a good prospect.