Sun Lichao, Zhao Hanying
Key Laboratory of Functional Polymer Materials, Ministry of Education, College of Chemistry, Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Nankai University , Tianjin 300071, China.
Langmuir. 2015 Feb 17;31(6):1867-73. doi: 10.1021/la5040036. Epub 2015 Feb 4.
Lipid membrane fusion is a fundamental process in nature. In the fusion process two distinct bilayers merge the hydrophobic layers, and an interconnected structure is produced. In this research, the fusion of polymer membrane self-assembled by cleaved pinned micelles is investigated. Disulfide-tethered poly(tert-butyl acrylate-block-styrene) diblock copolymer brushes on the surfaces of silica particles were prepared by the "grafting to" or "grafting from" method. In acetone, the diblock copolymer brushes self-assemble into pinned micelles. Upon cleavage from the surfaces of the silica particles with n-tributylphosphine, the pinned micelles self-assemble into vesicles. In the meanwhile, thiol groups at the ends of the block copolymer brushes were produced in the cleavage reaction. Because of the oxidation of the thiol groups and the formation of the disulfide bonds, the vesicle structures are fused into bigger hollow structures and fiber-like structures. The further fusion of the fiber-like structures results in precipitation of the polymer from the solution.
脂质膜融合是自然界中的一个基本过程。在融合过程中，两个不同的双层膜合并疏水层，并产生一个相互连接的结构。在本研究中，对由裂解的固定胶束自组装而成的聚合物膜的融合进行了研究。通过“接枝到”或“接枝从”方法在二氧化硅颗粒表面制备了二硫键连接的聚（丙烯酸叔丁酯 - 嵌段 - 苯乙烯）二嵌段共聚物刷。在丙酮中，二嵌段共聚物刷自组装成固定胶束。用三正丁基膦从二氧化硅颗粒表面裂解后，固定胶束自组装成囊泡。同时，在裂解反应中产生了嵌段共聚物刷末端的硫醇基团。由于硫醇基团的氧化和二硫键的形成，囊泡结构融合成更大的中空结构和纤维状结构。纤维状结构的进一步融合导致聚合物从溶液中沉淀出来。
