丝裂霉素C纳米胶束的制备、表征及体外抗肿瘤活性评价

Preparation,characterization and evaluation of antitumor activity of mitomycin nanomicelles

目的以聚乙二醇-芴甲氧羰酰基-布洛芬(PEG2K-Fmoc-Ibuprofen,PEG2K-FIbu)胶束为载体,制备丝裂霉素载药胶束(PEG2K-FIbu/MMC)并对其进行表征及体外抗肿瘤活性评价。方法合成PEG2K-FIbu胶束载体,采用薄膜分散法制备丝裂霉素C载药胶束溶液,通过核磁共振、临界胶束浓度、粒径、多分散指数、形态、紫外全波长扫描、载药量、包封率和稳定性对空白胶束和载药胶束溶液进行表征,单因素试验筛选制备工艺并考察MMC和PEG2K-FIbu/MMC的体外释放度。以丝裂霉素C和空白胶束作为对照,用MTT法测定载药胶束对人肺癌细胞A549、人胃癌细胞MGC-803、人肝癌细胞HepG2、人乳腺癌细胞MCF-7、小鼠乳腺癌细胞4T1的体外抗肿瘤活性。结果聚合物胶束(PEG2K-FIbu)成功合成并经1H-NMR得到确证,CMC值为0.512 mg·L^-1,胶束粒子外观圆整且分散良好,平均粒径为(14.6±2.8)nm,由薄膜分散法制备的载药胶束(PEG2K-FIbu/MMC)平均粒径为(103.2±0.9)nm,在载体药物摩尔比为2.5∶1时载药胶束的载药量和包封率分别为5.2%和96.6%。相比MMC注射液,PEG2K-FIbu/MMC载药胶束具有一定的缓释能力。PEG2K-FIbu/MMC胶束在低剂量时(20 mg·L^-1以下)对肿瘤细胞的抑制作用较单使用MMC低,但在较高剂量(20mg·L^-1及以上)对肿瘤细胞的杀伤作用与单独使用MMC无显著差异。结论PEG2K-FIbu/MMC载药胶束具有高包封率、高稳定性,具备较强的抗稀释能力和良好的缓释性能,解决了MMC稳定性差、半衰期短的问题,而且PEG2K-FIbu载体能有效介导MMC向肿瘤细胞的细胞内递送。

Objective To prepare mitomycin C-loaded micelles(PEG2K-FIbu/MMC)with PEG2K-Fmoc-Ibuprofen(PEG2K-FIbu)micelles as carrier,characterize them and evaluation of antitumor activity in vitro.Methods The PEG2K-FIbu micelles carrier was synthesized and PEG2K-FIbu/MMCmicelles were prepared by thin film dispersion method.The PEG2K-FIbu and PEG2K-FIbu/MMC micelles were characterized by 1HNMR,c ritical micelle concentration(CMC),particle size,polydispersity index(PDI),morphology,UV full-wavelength scanning,drug loading capacity,drug loading efficiency andstability.The single-factor test was used to screen the preparation process and the in vitro release of PEG2K-FIbu/MMC was examined using MMC injection as a control.Using MMCand PEG2K-FIbu micelles as a control,MTT assay was used to determine the in vitro antitumor activity of PEG2K-FIbu/MMC micelles to human lung cancer A549,human gastric cancer MGC-803,human liver cancer HepG2,human breast cancer MCF-7,and murine breast cancer 4T1 cells.Results The polymer micelles(PEG2K-FIbu)were successfully synthesized and confirmed by 1H-NMR.The CMC value was 0.512 mg·L^-1.The micelles were round and well dispersed,and the average particle size was(14.6±2.8)nm.The PEG2K-FIbu/MMC micellesprepared by the film dispersion method have an average particle diameter of(103.2±0.9)nm,and the drug loading capacity and drug loading efficiencywhen the carrier drug molar ratio is 2.5∶1 were 5.2%and 96.6%,respectively.Compared with MMC injection,PEG2K-FIbu/MMC micelles have a certain sustained releasecapacity.The inhibitory effect of PEG2K-FIbu/MMC micelles on tumorcells at low doses(below 20 mg·L^-1)was lower than that of MMC alone,but at higher doses(20 mg·L^-1 and above)was not significantly different from that of MMC injection.Conclusion PEG2K-FIbu/MMC micelles have high drug loading efficiency,high stability,strong anti-dilution ability and good sustained-release properties,which solves the problem of poor stability and short half-life of MMC,and PEG2K-FIbu vector effectively mediate intracellular delivery of MMC to tumor cells.