【摘要】 本研究的目的是用O 羧甲基壳聚糖作乳化剂和表面修饰剂 ,采用超声乳化法制备聚乳酸载药纳米微粒 ,并对聚乳酸载药纳米微粒进行表面修饰 ,然后分别对载药纳米微粒的表面形貌、粒径分布、微粒结构、表面元素、体外释放和肿瘤细胞抑制率等微粒性能进行考察与评价。实验证明 ,O 羧甲基壳聚糖可用于制备纳米药物载体系统 ,对聚乳酸载药纳米微粒的制备起到很好的乳化性能和表面修饰作用。采用复乳法制备包载 5 Fu的PLA/O CMC纳米微粒的平均粒径在 5 0nm ,在PBS缓冲溶液中释放时间可达 12d。在对胃癌、乳腺癌和大肠癌三种肿瘤细胞的抑制率测定实验中 ,PLA/O CMC纳米微粒的肿瘤细胞抑制率分别可以达到 72 .8%、77.3%和 75 .6 % ,接近或等同于游离 5 Fu药物的抑制率。在作用时间上 ,PLA/O CMC载药纳米微粒也显示出良好的缓释效应。更多还原

【Abstract】 The aim of this study is using biodegradable O-Carboxymethylated Chitosan(O-CMC) to modify 5-fluorouracil(5-FU)-loaded PLA nanoparticles (NPs) by multiple emulsion technology. The glomeration ability, appearance, structure, and surface of NPs were characterized by AFM, TEM, and XPS. The results show that O-CMC can be used to prepare drug-loaded NPs as a emulsifier and modifier and the mean size of NPs obtained was 50nm. Three kinds of tumor cell lines including 803 gastric carcinoma cells, MDA-MB-231 breast carcinoma cells and HCT-8 colorectal cells were used to investigate the cytotoxicity of NPs. It is demonstrated that the 5-FU-loaded NPs have high cytotoxicity of 72.8%, 77.3%, and 75.6% respectively on the three kinds of cells. In addition the 5-FU-loaded NPs show a sustained release for 12 days.更多还原