Department of Applied Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan.
Biomacromolecules. 2012 May 14;13(5):1554-63. doi: 10.1021/bm300254s. Epub 2012 Apr 24.
Self-degradable antimicrobial copolymers bearing cationic side chains and main-chain ester linkages were synthesized using the simultaneous chain- and step-growth radical polymerization of t-butyl acrylate and 3-butenyl 2-chloropropionate, followed by the transformation of t-butyl groups into primary ammonium salts. We prepared a series of copolymers with different structural features in terms of molecular weight, monomer composition, amine functionality, and side chain structures to examine the effect of polymer properties on their antimicrobial and hemolytic activities. The acrylate copolymers containing primary amine side chains displayed moderate antimicrobial activity against E. coli but were relatively hemolytic. The acrylate copolymer with quaternary ammonium groups and the acrylamide copolymers showed low or no antimicrobial and hemolytic activities. An acrylate copolymer with primary amine side chains degraded to lower molecular weight oligomers with lower antimicrobial activity in aqueous solution. This degradation was due to amidation of the ester groups of the polymer chains by the nucleophilic addition of primary amine groups in the side chains resulting in cleavage of the polymer main chain. The degradation mechanism was studied in detail by model reactions between amine compounds and precursor copolymers.
具有阳离子侧链和主链酯键的可自降解抗菌共聚物是通过使用 t-丁基丙烯酸酯和 3-丁烯基 2-氯丙酸盐的同时链增长和逐步自由基聚合，随后将 t-丁基转化为伯铵盐来合成的。我们制备了一系列具有不同结构特征的共聚物，包括分子量、单体组成、胺官能度和侧链结构，以研究聚合物性质对其抗菌和溶血活性的影响。含有伯胺侧链的丙烯酸酯共聚物对大肠杆菌具有中等的抗菌活性，但溶血活性相对较高。含有季铵基团的丙烯酸酯共聚物和丙烯酰胺共聚物表现出低或无抗菌和溶血活性。具有伯胺侧链的丙烯酸酯共聚物在水溶液中降解为低分子量的低聚物，抗菌活性降低。这种降解是由于聚合物链上的酯基团通过侧链上的伯胺基团的亲核加成进行酰胺化，从而导致聚合物主链的断裂。通过胺化合物和前体共聚物之间的模型反应详细研究了降解机制。
