Preparation and Antibacterial Properties of Polyelectrolyte Complexed Nanoparticles Aggregated from PHMG and Sodium Caffeate

In this study, we synthesized polyelectrolyte complexed nanoparticles using an ion exchange reaction between poly(hexamethylene guanidine hydrochloride) and sodium caffeate. The morphology of the obtained antiparticle was observed by scanning electron microscopy, and FT-IR and XPS were employed for the structural characterization. The antimicrobial properties of <i>E. coli</i> and <i>S. aureus</i> were characterized through minimum inhibitory concentration (MIC), growth curve analysis, plate colony counting method, and crystal violet method. Notably, the sample showed a 100% bactericidal rate against <i>E. coli</i> at 0.095 μg/mL and against <i>S. aureus</i> at 0.375 μg/mL within 1 h, demonstrating excellent antimicrobial performance against <i>E. coli</i> and <i>S. aureus.</i> The CA-PHMG-containing acrylic resin coatings exhibited exceptional antimicrobial and antiadhesive properties when examined under an inverted fluorescence microscope, particularly at a 4% weight concentration of the antibacterial agent. This study holds vast potential for development in the field of antimicrobial coatings.