Antimicrobial activity evaluation of a novel triblock cationic copolymer (PHEMA-b-PNIPAM-b-PVEAH)

Background and objective: Antimicrobial compounds are considerably interested because of their importance in control of biological contaminants. Several techniques have been used for fabrication of novel and efficient antimicrobial compounds. The aim of present work was to develop a durable cationic antimicrobe based on triblock copolymer. Materials and methods: Novel poly(2-hydroxyethyl methacrylate)-b-poly(N-isopropyl acrylamide)-b-poly (N-4-vinylbenzyl), N,N-diethylamine hydrochloride (briefly named PHEMA-b-PNIPAM-b-PVEAH or ABC) cationic triblock copolymer was synthesized via reversible addition fragmentation transfer (RAFT) polymerization as antimicrobial compound. Chemical structure of ABC triblock copolymer was characterized by Fourier Transform Infrared and 1H Nuclear Magnetic Resonance spectroscopy. Furthermore, the antimicrobial activity of cationic triblock copolymer was examined on four micro-organisms including Bacillus cereus, Staphylococcus aureus, Escherichia coli and Candida albicans. Results and conclusion: Molecular weight of blocks in the copolymer including PHEMA, PHEMA-b-PNIPAM and PHEMA-b-PNIPAM-b-PVEAH was 10950, 17103 and 26165 g mol-1, respectively. Results showed remarkable antibacterial activity so that inhibition diameter of B. cereus and S. aureus were 25, 29, 34 mm and 32, 37, 41 mm, respectively. Low inhibition was detected against E. coli (14, 17 and 21 mm) and the highest inhibition was observed for C. albicans (48, 81 and 98 mm). Acceptable antibacterial and high anti-yeast activity was observed for ABC. Therefore, it could be used in therapeutic purposes and microbial suppression.

Antimicrobial activity evaluation of a novel triblock cationic copolymer (PHEMA-b-PNIPAM-b-PVEAH) Keywords:

Antimicrobial activity , Bacillus cereus , candida albicans , cationic triblock copolymer , Escherichia coli , Staphylococcus aureus