PBLG-PEG-PBLG嵌段共聚物的合成及其CHO细胞毒性

Preparation of PBLG-PEG-PBLG Block Copolymers and Their CHO Cell Toxicity

以端氨基聚乙二醇(AT-PEG)引发谷氨酸苄酯N-羧酸酐(BLG-NCA)开环聚合得到聚谷氨酸苄酯-聚乙二醇-聚谷氨酸苄酯嵌段共聚物(PBLG-PEG-PBLG,缩写为GEG),用GPC、IR、1H NMR测试技术表征了共聚物的结构;在GEG膜表面培养中国仓鼠肺泡成纤维细胞(CHO),用光学显微镜和扫描电子显微镜观察聚合物表面细胞粘附、生长、繁殖的情况。结果表明,AT-PEG能引发BLG-NCA开环聚合形成嵌段共聚物,所有的聚合物都没有细胞毒性,细胞在某些共聚物上的生长和繁殖比均聚物好。当PEG的分子量为2 000,且PEG单体单元的摩尔含量占共聚物中总单体含量的59%时,细胞不能贴附在共聚物表面。通过控制共聚物中PEG嵌段的含量可调节细胞在聚合物表面上的粘附和生长。

The block copolymers of poly （y-benzyl L-glutamate） and poly （ethylene glycol） （PBLG-PEG- PBLG, GEG） were prepared via ring-opening polymerization of γ-benzyl L-glutamate N-carboxyanhydride initiated by amine-terminated PEG （AT-PEG）. The copolymer structure was characterized by GPC, IR and ^1H NMR. CHO cells were incubated on the polymer surfaces for 24 h by direct contact method, and then observed via photo electron microscope and SEM. The results demonstrate that GEG could be obtained with AT-PEG as initiator and all the polymers were nontoxic to CHO cells. The SEM results show that the adhesion and proliferation of the cells were better on some of the copolymers than on PBLG. When the molecular weight of PEG was 2 000 dalton, and the molar ratio of EG monomer was 59% of the total monomer in the block copolymer, the ceils could copolymer could adjust the not adhere to the copolymer surfaces. Controlling the content of PEG in the adhesion and proliferation of the cells on copolymer surfaces.