目的 利用聚多巴胺（PDA）为载体，构建丹参（SMRR）PDA纳米递药系统（PDA-SMRR），能够大剂量负载多种丹参水溶性成分，使其更好地发挥抗氧化应激作用。方法 制备PDA-SMRR纳米粒，通过单因素实验考察并优化处方工艺；通过激光粒度分析仪和透射电子显微镜考察纳米粒的粒径、电位和形态；透析法分析载药量及累积释放率；提取并培养大鼠乳鼠心肌细胞；CCK-8实验考察PDA-SMRR的生物安全性并验证PDA-SMRR对氧化应激损伤的心肌细胞的保护作用。结果 最优载药工艺为pH值为3.5，载药时间为12 h，载药温度为室温，并成功制备PDA-SMRR；其形态规整、大小均匀，测得纳米粒粒径为（459.2±4.5）nm，体外释放表明该递药系统释放SMRR较缓慢；CCK-8实验说明PDA-SMRR生物安全性良好且纳米粒可以降低氧化应激造成的心肌细胞损伤。结论 PDA-SMRR可以作为丹参多成分药物储库，载药量高，具有缓释效应，可以有效减少氧化应激对心肌细胞的损伤。

Objective Using polydopamine (PDA) as a carrier to construct a Salviae Miltiorrhizae Radix et Rhizoma (SMRR) nano-delivery system (PDA-SMRR), which can load a large number of SMRR water-soluble components and better exert antioxidation and antistress effect. Methods PDA-SMRR nanoparticles (PDA-SMRR) were prepared, and the prescription process was investigated and optimized by single-factor experiments. The particle size, potential, and morphology of the nanoparticles were examined by a laser particle size analyzer and a transmission electron microscope. The drug loading and cumulative release rate were analyzed by dialysis. The cardiomyocytes of neonatal rats were extracted and cultured. The CCK-8 experiment was used to investigate the biological safety of PDA-SMRR and verify the protective effect of PDA-SMRR on oxidative stress-induced cardiomyocytes. Results The optimal drug loading process was pH value 3.5, drug loading time was 12 h, drug loading temperature was room temperature, and PDA-SMRR was successfully prepared. The morphology and size of the nanoparticles were regular and uniform. The particle size and Zeta potential were (459.2±4.5) nm, (3.01±0.3) mV; In vitro release experiments indicated that SMRR was released slowly by the delivery system. CCK-8 experiments showed that PDA-SMRR had good biological safety and nanoparticles can reduce damaged cardiomyocytes caused by oxidative stress. Conclusion PDA-SMRR can be used as a multi-component medicine depot for SMRR, with high drug loading and sustained release effect, which can effectively reduce the damage of oxidative damage on myocardial cells.

R283.6

江苏省自然科学基金优秀青年基金项目（BK20190094）；江苏高校"青蓝工程"资助；苏州市科技发展计划基金项目（SYSD2019187，SYSD2018242）；国家重点研发计划-中医药现代化研究（2018YFC1706905）