Ag/Ag2O with NIR-Triggered Antibacterial Activities: Photocatalytic Sterilization Enhanced by Low-Temperature Photothermal Effect

Purpose A synergistic antibacterial system employing photocatalytic performance and low-temperature photothermal effect (LT-PTT) with the potential for infectious skin wound healing promotion was developed.Methods Ag/Ag2O was synthesized with a two-step method, and its physicochemical properties were characterized. After its photocatalytic performance and photothermal effect were evaluated under 0.5 W/cm2 808 nm NIR laser irradiation, its antibacterial activities in both planktonic and biofilm forms were then studied in vitro targeting Staphylococcus Aureus (S. aureus), and the biocompatibility was tested with L-929 cell lines afterward. Finally, the animal model of dorsal skin wound infection was established on Sprague-Dawley rats and was used to assess infectious wound healing promotion of Ag/Ag2O in vivo.Results Ag/Ag2O showed boosted photocatalytic performance and local temperature accumulation compared with Ag2O when exposed to 0.5 W/cm2 808 nm NIR irradiation, which therefore endowed Ag/Ag2O with the ability to kill pathogens rapidly and cleavage bacterial biofilm in vitro. Furthermore, after treatment with Ag/Ag2O and 0.5 W/cm2 808 nm NIR irradiation, infectious wounds of rats realized skin tissue regeneration from a histochemical level.Conclusion By exhibiting excellent NIR-triggered photocatalytic sterilization ability enhanced by low-temperature photothermal effect, Ag/Ag2O was promising to be a novel, photo-responsive antibacterial agent.