Injectable Hydrogel Incorporated with Iron‐Doped Carbon Dots Exhibiting Peroxidase‐Like Activity for Antibacterial Therapy and Wound Healing

Abstract The increasing bacterial resistance highlights the necessity of developing superior antibacterial materials. Metal‐doped carbon dots (CDs), a crucial branch of carbon‐based nanozymes, exhibit efficient antibacterial properties using the reactive oxygen species (ROS) effect. In this study, iron‐doped carbon dots (Fe‐CDs) are synthesized with high peroxidase‐like (POD‐like) activity using natural hemin as a precursor for the first time. The formation of Fe‐CDs remarkably improves the water solubility of hemin showing excellent biocompatibility. Additionally, iron is doped from hemin to the CDs surface, reducing the risk of trial‐and‐error associated with adding an external iron source. The Fe‐CDs‐hydrogel system is constructed via the incorporation of Fe‐CDs into a dual‐crosslinked injectable hydrogel, taking advantage of the synergistic effects. The system enhances the mechanical properties of hydrogel and serves as an excellent carrier for Fe‐CDs. It exhibits effective antibacterial activity at low hydrogen peroxide (H 2 O 2 ) concentrations (10 −4 m ) via the activation of Fenton‐like reaction‐triggered POD‐like catalytic activity and the electrostatic interactions. The system further demonstrates excellent healing efficacy in a bacteria‐infected wound model by reducing inflammation levels and accelerating the regeneration of tissues. This study provides a novel approach for applying nanozymes in antibacterial therapy and wound healing.