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

Calcium peroxide (CaO 2 ) is commonly used as a hydrogen peroxide (H 2 O 2 ) donor to eliminate bacterial infections. However, the rapid dissociation of CaO 2 and the explosive release of H 2 O 2 have limited the development of CaO 2 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 CaO 2 nanoparticles while simultaneously regulating the concentration of H 2 O 2 within the bacterial infection microenvironment. AgNPs are capable of reacting with H 2 O 2 under mildly acidic conditions to produce hydroxyl radicals with enhanced antimicrobial activity. The antimicrobial results demonstrated that AgNPs functionalized silicon dioxide-coated calcium peroxide (CaO 2 @SiO 2 /AgNPs) nanoparticles exhibited enhanced bactericidal activity compared to AgNPs or CaO 2 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.