title: Design and synthesis of self-degradable antibacterial polymers by simultaneous chain- and step-growth radical copolymerization.
abstract: 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.
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan.
authors.forename: Masato
authors.initials: M
authors.lastname: Mizutani
authors.forename: Edmund F
authors.initials: EF
authors.lastname: Palermo
authors.forename: Laura M
authors.initials: LM
authors.lastname: Thoma
authors.forename: Kotaro
authors.initials: K
authors.lastname: Satoh
authors.forename: Masami
authors.initials: M
authors.lastname: Kamigaito
authors.forename: Kenichi
authors.initials: K
authors.lastname: Kuroda
mesh_terms: D000179:Acrylates / Q000737:chemistry; D000900:Anti-Bacterial Agents / Q000138:chemical synthesis / Q000378:metabolism / Q000494:pharmacology*; D015195:Drug Design; D004926:Escherichia coli / Q000187:drug effects*; D005609:Free Radicals / Q000138:chemical synthesis / Q000378:metabolism / Q000494:pharmacology; D006461:Hemolysis / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D015394:Molecular Structure; D058105:Polymerization; D011108:Polymers / Q000138:chemical synthesis / Q000378:metabolism / Q000494:pharmacology*
chemical_list: D000179:Acrylates; D000900:Anti-Bacterial Agents; D005609:Free Radicals; D011108:Polymers