GelMA-GelDopa-Sr double-network hydrogel promotes skin regeneration by enhancing angiogenesis and macrophage polarization.

Introduction: Chronic skin defects typically exhibit persistent inflammation, damaged cell regeneration, and insufficient vascularization, all of which severely impede the healing process. Traditional skin dressings merely serve to cover the wound and do not actively promote wound healing. They lack anti-inflammatory capabilities and only minimally regulate immune cells, and their poor biocompatibility can lead to foreign body reactions. Some traditional dressings adhere to the defect area, and during dressing changes, they may cause secondary trauma, resulting in pain and tearing of new tissue. Therefore, it is of great significance to develop a functional dressing that can simultaneously regulate inflammatory responses, promote angiogenesis, and accelerate tissue regeneration. Methods: In this study, gel methacrylamide (GelMA), gel dopamine (GelDopa) were combined with strontium ions (Sr Results: This dual-network design provided several functional advantages: the photopolymerization properties of GelMA enabled rapid and controllable gelation; the catecholamine derived from GelDopa imparted antioxidant capabilities, thereby reducing oxidative stress; and Sr Discussion: The results show that the GelMA-GelDopa-Sr dual-network composite hydrogel exerts antioxidant, angiogenic promotion and immune regulation effects through a synergistic mechanism, which overcomes the challenges of inflammation and insufficient vascularization during skin tissue regeneration and significantly accelerates the regeneration of skin tissues. This research offers new ideas and experimental basis for the design and application of multifunctional hydrogels in the repair of chronic wounds.