Engineering Robust Silver-Decorated calcium peroxide Nano-Antibacterial Platforms for chemodynamic enhanced sterilization

Abstract

Calcium peroxide (CaO₂) is commonly used as a hydrogen peroxide (H₂O₂) donor to eliminate bacterial infections. However, the rapid dissociation of CaO₂ and the explosive release of H₂O₂ have limited the development of CaO₂ in the antibacterial field. Therefore, a series of silver nanoparticles (AgNPs) functionalized bacteria-triggered smart hydrogels (CSA-H) that integrate sustained release of nanoparticles and localized chemodynamic sterilization were constructed. The pH-responsive hydrogel formed through the Schiff base reaction enables the responsive release of CaO₂ nanoparticles while simultaneously regulating the concentration of H₂O₂ within the bacterial infection microenvironment. AgNPs are capable of reacting with H₂O₂ under mildly acidic conditions to produce hydroxyl radicals with enhanced antimicrobial activity. The antimicrobial results demonstrated that AgNPs functionalized silicon dioxide-coated calcium peroxide (CaO₂@SiO₂/AgNPs) nanoparticles exhibited enhanced bactericidal activity compared to AgNPs or CaO₂ alone. Furthermore, CSA-H hydrogels exhibited significant antibacterial activity against S. aureus and E. coli under the dual effect of AgNPs and pH-driven Fenton-like reactions. This chemodynamic antibacterial platform is environmentally responsive and provides a promising strategy for creating multifunctional hydrogels loaded with nano-enzymes, thus advancing the development of AgNPs in chemodynamic-antibacterial related applications.