Copper peroxide-decorated Prussian blue for effective bacterial elimination via photothermal-enhanced and H2O2-releasing chemodynamic therapy

Bacterial infection is a major impediment towards wound healing and threaten human health worldwide. Traditional antibiotic therapy poses a high risk of inducing bacterial resistance, thus nanomaterial-based synergistic bactericidal strategy as effective alternatives have received tremendous attention. Herein, a NIR/pH-dual responsive nanoplatform was fabricated for synergistic photothermal and chemodynamic therapy (PTT/CDT). Prussian blue (PB) were employed as supporting material, while copper peroxide (CP) were growth in situ on PB surface, resulting in a core-shell structured nanoplatform (designated as PC). PB core served as photothermal/Fenton catalyst dual agents, and CP shell could co-release Cu²⁺ and H₂O₂ under acidic bacterial infection environment, realizing synergistic PTT and H₂O₂-releasing CDT. Under NIR irradiation, PC exhibited photothermal-enhanced Fenton-like reaction feature and the hyperthermia facilitated Cu²⁺ release, leading to the rapid conversion of H₂O₂ into toxic •OH to effectively kill Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus), eradicating S. aureus biofilm. Moreover, the released Cu²⁺ could improve the bactericidal effect of CDT via the depletion of GSH and significantly promote cell migration. Furthermore, in vivo experiments demonstrated PC with good biocompatibility exhibited robust bactericidal effect and promoted wound healing. Overall, this versatile nanoplatform offered an efficacious and safe antibiotic-free strategy for bacterial infection treatments.