Antimicrobial activity of Fe-loaded chitosan nanoparticles

To increase the antimicrobial activities of chitosan, chitosan nanoparticles loaded with Fe 2+ or Fe 3+ were prepared by surfactant‐assisted chitosan chelating Fe 2+ , Fe 3+ and ionic gelation chitosan. Their chelating rates were determined by spectrophotometry. The particle sizes and zeta potentials of chitosan nanoparticles loaded with Fe 2+ or Fe 3+ were measured by size and zeta potential analysis. The nanoparticles antimicrobial activities were evaluated by different concentration against Escherichia coli, Staphylococcus aureus, Candida albicans in vitro. Results showed that the mean diameter of chitosan nanoparticles loaded with Fe 2+ or Fe 3+ were 206.4 and 195.2 nm, respectively. Their zeta potentials were +28.82 and +28.26 mV, respectively. The chelating rate of chitosan nanoparticles loaded with Fe 2+ was greatly higher than with Fe 3+ . Their antimicrobial activity was showed greatly higher at lower concentrations compared to chitosan, and the antibacterial effect of chitosan nanoparticles loaded with Fe 2+ or Fe 3+ was preliminary observed.