An Immune-Regulating Polysaccharide Hybrid Hydrogel with Mild Photothermal Effect and Anti-Inflammatory for Accelerating Infected Wound Healing.

Bacterial infections and excessive inflammation present substantial challenges for clinical wound healing. Hydrogels with mild photothermal (PTT) effects have emerged as promising agents owing to their dual actions: positive effects on cells and negative effects on bacteria. Here, an injectable self-healing hydrogel of oxidized konjac glucomannan/arginine-modified chitosan (OKGM/CS-Arg, OC) integrated with protocatechualdehyde-@Fe (PF) nanoparticles capable of effectively absorbing near-infrared radiation is synthesized successfully. The OC/PF hydrogels exhibit excellent mechanical properties, biocompatibility, and antioxidant activity. Moreover, in synergy with PTT, OC/PF demonstrates potent antibacterial effects while concurrently stimulating cell migration and new blood vessel formation. In methicillin-resistant Staphylococcus aureus-infected full-thickness mouse wounds, the OC/PF hydrogel displays remarkable antibacterial and anti-inflammatory activities, and accelerates wound healing by regulating the wound immune microenvironment and promoting M2 macrophage polarization. Consequently, the OC/PF hydrogel represents a novel therapeutic approach for treating multidrug-resistant bacterial infections and offers a technologically advanced solution for managing infectious wounds in clinical settings.