Co-delivery of antimicrobial peptide and Prussian blue nanoparticles by chitosan/polyvinyl alcohol hydrogels

Altered skin integrity increases the chance of infection, and bacterial infections often lead to a persistent inflammatory response that prolongs healing time. Functional artificial hydrogels are receiving increasing attention as suitable wound dressing barrier. However, the antimicrobial effect of the new dressing still needs to be explored in depth. In this work, the antimicrobial peptide MSI-1 was covalently attached to chitosan-modified poly (vinyl alcohol) hydrogels mixed with Prussian blue nanoparticles (PBNPs) via a primary amine group coupled to a carboxyl group. The synthesized hydrogel has a long-lasting antimicrobial surface and is able to maintain its bactericidal effect on Staphylococcus aureus and Escherichia coli for 24 h. Due to the presence of PBNPs, the hydrogel was able to rise to 48.3 °C within 10 min under near infrared (NIR) light irradiation at a wavelength of 808 nm and maintain this mild temperature to avoid bacterial biofilms. The hydrogel showed >90 % survival in co-culture with cells for 3 d and did not damage major organs in animal experiments. Thus, the photothermal dual-mode antimicrobial hydrogel synthesized in this study increases the selectivity as a safe and efficient wound dressing for the treatment of infected skin defects.