A single-component photo-crosslinked chitosan hydrogel with inherent antimicrobial and antioxidant capabilities for wound healing

The development of multifunctional chitosan-based hydrogels for wound healing often relies on complex compositions or external initiators, which can limit their clinical applicability. Herein, we report a novel chitosan-based hydrogel dressing (LQCS) engineered through a facile modification with lipoic acid (LA) and a quaternary ammonium salt (QAS), enabling intrinsic antibacterial and antioxidant activities without complex components. A key innovation of this system is its initiator-free, UV-triggered gelation <i>via</i> disulfide ring-opening polymerization of LA, which facilitates <i>in situ</i> formation and conformal coverage of irregular wounds. The integrated QAS moieties endow the hydrogel with excellent broad-spectrum antimicrobial activity, demonstrating bactericidal rates of 90.1% against <i>Escherichia coli</i> and 92.3% against <i>Staphylococcus aureus</i>. Simultaneously, the LA component confers remarkable antioxidant capacity, effectively scavenging reactive oxygen species (ROS) at the wound site. In a full-thickness skin defect model, the LQCS hydrogel significantly accelerated wound closure by mitigating inflammation and promoting angiogenesis. This study presents a simple yet effective strategy for creating an all-in-one hydrogel dressing, which integrates green fabrication, multi-bioactivity, and pro-healing functions, holding great potential for advanced wound care.