Autocatalytic Self-Sorting in Biomimetic Polymer

作者：Zhou Kaiyi; Cao Hui; Gao Pan; Cui Zhigang; Ding Yi; Cai Yuanli

来源：Macromolecules, 2016, 49(6): 2189-2196.

DOI：10.1021/acs.macromol.6b00152

Autocatalytic self-sorting in the biomimetic poly(Cystarnine methacrylamide hydrochloride) (PCysMA) is presented, whose units comprise lysine-mimetic alkyl ammonium ions and cystine-mimetic alkyl disulfide spacers. The block copolymer with poly(2-hydroxypropyl-methacrylamide) was synthesized directly by RAFT in acidic water under visible light irradiation at 25 degrees C. Disulfide exchange can be initiated by the terminal thiolates as generated by alkalization-induced aminolysis. 65-67% CysMA units sort into hydrophobic polymer disulfides and water-soluble cystamine at pH 10.5. Moreover, intermediate reactions occur in the presence of copper ions, i.e., Cu(II)-NH2 coordination, aminolysis, NH2-to-SH substitution, and cupric-to-cuprous reduction in metal centers, thus autocatalytic self-sorting with essentially 100% conversion at pH 8.8, UV-vis spectroscopy, H-1. NMR, atomic absorption spectroscopy, and elemental analysis confirmed this ideal self-sorting. Dynamic light, scattering and atomic force microscopy identified supramolecular-to-supracolloidal self-assembly with concomitant release of cystamine molecules and intermediate cuprous complexes. Such a self-sorting underlines an amazing prospect for the use of a single polymer to achieve artificial reaction complexity, hierarchy, and metabolic process, with minimal synthetic efforts.

• 出版日期2016-3-22
• 单位苏州大学