A Multifunctional Nanozyme Hydrogel with Antibacterial, Antioxidative, and Photo-Induced Nitric Oxide-Supplying Properties for Promoting Infected Wound Healing

<b>Objectives:</b> To design a multifunctional nanozyme hydrogel with antibacterial, photo-responsive nitric oxide-releasing, and antioxidative properties for promoting the healing of infected wounds. <b>Methods:</b> We first developed ultra-small silver nanoparticles (NPs)-decorated sodium nitroprusside-doped Prussian blue (SNPB) NPs, referred to as SNPB@Ag NPs, which served as a multifunctional nanozyme. Subsequently, this nanozyme, together with geniposide (GE), was incorporated into a thermo-sensitive hydrogel, formulated from Poloxamer 407 and carboxymethyl chitosan, creating a novel antibacterial wound dressing designated as GE/SNPB@Ag hydrogel. The physical properties of a GE/SNPB@Ag hydrogel were systematically investigated. <b>Results:</b> After embedding the nanozyme and GE, the resulting GE/SNPB@Ag hydrogel retains its thermosensitive properties and exhibits sustained release characteristics. In addition to its catalase-like activity, the nanozyme demonstrates high photothermal conversion efficiency, photo-induced nitric oxide release, and antibacterial activity. In addition, the hydrogel exhibits favorable antioxidant properties and high biocompatibility. The results of animal experiments demonstrate that the composite hydrogel combined with laser irradiation is an effective method for promoting infected wound healing. <b>Conclusions:</b> In vitro and in vivo studies indicate that the resulting GE/SNPB@Ag hydrogel holds significant potential for the treatment of infected wounds and for further clinical applications.