An Injectable and Self-Adhesive Hydrogel Dressing Synergizing Natural Polysaccharide and Antioxidant for Promoting Healing of Chronic Wounds.

Although injectable hydrogels hold promise as dressings for chronic diabetic wounds, their clinical potential is often limited by non-specific actions and modest efficacy. To address these limitations, we developed a novel injectable hydrogel by integrating Bletilla striata polysaccharide (BSP)-known for its biocompatibility and wound-healing properties-with alpha-lipoic acid (LA), a potent antioxidant and antimicrobial agent. The preparation process is straightforward, requiring only the mixing of LA dissolved in Tris buffer (LA-Tris) and BSP solutions, and the gelation time was inversely correlated with BSP content. The resulting BSP/LA hydrogel displayed excellent injectability, appropriate mechanical strength, reliable tissue adhesion, and tunable degradation and swelling behaviors. By leveraging the synergistic effects of BSP and LA, the hydrogel exhibited strong broad-spectrum antimicrobial and antioxidant activities. Both in vitro and in vivo evaluations confirmed its high biocompatibility. Notably, in a diabetic rat wound model, the BSP/LA hydrogel significantly accelerated wound closure, attenuated inflammatory responses, stimulated collagen deposition, and enhanced neovascularization compared to control groups. These collective findings underscore the potential of this multifunctional injectable hydrogel as an effective and clinically viable dressing for the management of complex chronic wounds.