Effect of alkyl chain length and fluorine content on the surface characteristics and antibacterial activity of surfaces grafted with brushes containing quaternized ammonium and fluoro-containing monomers

• Published in: Colloids and surfaces, B, Biointerfaces B, Biointerfaces, 2021-06, Vol.202, p.111674-111674, Article 111674
• Main Authors: Lin, Po-An, Cheng, Chi-Hui, Hsieh, Kun-Ting, Lin, Jui-Che
• Format: Article
• Language: English
• Subjects: Alkyl chain length; Antibacterial activity; Degree of quaternization; Fluoro-containing monomer; Quaternary ammonium compound
• ISSN: 0927-7765; 1873-4367
• DOI: 10.1016/j.colsurfb.2021.111674

[Display omitted] •Materials with proper antimicrobial adhesion and antibacterial activity are needed.•Surface initiated RAFT polymerization was utilized for grafting copolymeric brushes.•QACs with different alkyl chain length and fluorine-containing monomer were used.•Use of long alkyl chain and fluoro-monomer enhances surface degree of quaternization.•Mixture of QAC with C8 chain and fluoro-monomer is the choice for surface grafting. Although considerable efforts have been made to vary the alkyl chain length in the quaternary ammonium compounds (QACs) for optimizing the antibacterial activity, only few researchers have systematically investigated the combinatory effects of alkyl chain length and another acryl monomers with the different chemical configuration on the antibacterial activity of the modified substrate. In this study, by surface grafting of various copolymeric brushes, different modified cotton substrates were prepared by surface-initiated reversible addition-fragmentation chain transfer (RAFT) polymerization reaction for exploring the effects of alkyl chain length of QACs and the fluorine content on antibacterial and anti-microbial adhesion characteristics. The quaternized monomers used were prepared by quaternization of 2-(dimethylamino) ethyl methacrylate (DMAEMA) with 1-bromooctane (DMAEMA + 8), and 1-bromopropane (DMAEMA + 3). The fluoro-containing monomer was 2,2,2-Trifluoroethyl methacrylate (TFEMA). Ethyl methacrylate (EMA) was also used for comparison. Results have shown that the optimal antibacterial and anti-microbial adhesion characteristics were noted on the substrates grafted with DMAEMA + 8 and TFEMA. This can be attributed to the enhanced degree of surface quaternization due to the hydrophobic interactions between the grafted TFEMA and DMAEMA + 8 chains, leading to an increase in antibacterial efficacy of modified cotton substrates.