An Antioxidant Hydrogel Based on Chitosan/Dextran with Composited Polydopamine-Coated CuS for Synergistic Antibacterial Wound Healing

To cope with wound complications caused by bacterial infection, this study developed a polysaccharide-based hydrogel from a chitosan-tannic acid conjugate (CS-TA) and 3-aminophenylboronic acid-grafted dextran oxidant (ODP) through double-network cross-linking. The polydopamine-coated CuS nanoparticles (PDA@CuS) with photothermal properties and quercetin (QT) with antioxidant properties were loaded into the hydrogel to fabricate the multifunctional QT-PDA@CuS/hydrogel as a wound dressing. The mild photothermal effect of PDA@CuS, combined with the antimicrobial properties of CS-TA and quercetin, effectively inhibited Staphylococcus aureus and Escherichia coli with inhibition ratios of approximately 98.0% and 99.0%. Quercetin (QT), tannic acid, and polydopamine also confer superior antioxidant characteristics to the hydrogel, playing a crucial role in reducing oxidative stress and inflammation. Moreover, this multifunctional hydrogel also facilitated angiogenesis and collagen deposition to promote the repair of infected skin wounds in vivo. In summary, the QT-PDA@CuS/hydrogel dressing holds significant potential for clinical applications in infected wound treatment.