Poly([2-(methacryloyloxy)ethyl]trimethyl ammonium chloride) (METAC) and the gels were prepared and evaluated for their bactericidal and fungicidal activities. The antimicrobial properties of poly(METAC) were tested against Escherichia coli (E. coli), Bacillus subtilis (B. subtilis), Saccharomyces cerevisiae (Sa. cerevisiae), methicillin-susceptible Staphylococcus aureus (MSSA), methicillin-resistant Staphylococcus aureus (MRSA), Pseudomonas aeruginosa (P. aeruginosa), and Candida albicans (C. albicans). Moreover, the structural forms of the linear and cross-linked poly(METAC) were investigated for their influences on bacterial aggregation, precipitation, and cell-death. To our knowledge, this is the first report on the comparison of the antimicrobial properties of poly(METAC) and poly(METAC)-gels. The bactericidal and fungicidal activities were evaluated by determining minimum inhibitory concentrations (MICs), UV⁻Vis spectroscopy, and fluorescence and confocal microscopies. The MICs were found to be 123 (MSSA), 123 (MRSA), 123 (P. aeruginosa), 370 (E. coli), 123 (B. subtilis), 370 (C. albicans), and 370 μg/mL (Sa. cerevisiae), as determined by broth dilution, and 370 (MSSA), 370 (MRSA), 370 (P. aeruginosa), 3300 (E. coli), 370 (B. subtilis), 1100 (C. albicans), and >10,000 μg/mL (Sa. cerevisiae), as determined by paper disc diffusion (on solid medium). The poly(METAC)-gels achieved rapid adsorption/precipitation of bacteria via the cationic surface charge. Thus, these poly(METAC)-based polymers can potentially be used as antibacterial materials.
Keywords: antimicrobial polymer; cationic polymer; drug-resistant bacteria; poly([2-(methacryloyloxy)ethyl]trimethyl ammonium chloride).