Skin-inspired biogel/nanofiber composite dressing for sustained co-delivery of asiaticoside and zinc ions enabling synergistic burn wound healing.

Deep burn wounds present significant challenges to rapid healing due to their complex microenvironment, characterized by multiple bacterial infections, excessive oxidative stress and blocked angiogenesis. Herein, a skin-inspired biogel/nanofiber composite dressing composed of gelatin-based biogel and electrospun nanofiber membrane co-loaded with asiaticoside (AS) and ZnO is designed and prepared for regulating the wound microenvironment to accelerate deep burn wound healing. Sodium pyrrolidone carboxylate (PCA-Na) as a natural moisturizing factor is introduced into the gelatin solution to prepare a skin-inspired biogel with strong tissue adhesion, high mechanical strength and good water retention capacity. The sustained release of AS and zinc ions (Zn2+) co-loaded into nanofibers promotes antibacterial activity, anti-inflammatory effects, angiogenesis and collagen deposition. The composite dressing exhibits excellent adhesion to red blood cells and platelets, hemocompatibility and cytocompatibility. Furthermore, it also presents remarkable rapid hemostasis capability with the hemostatic time greatly shortened to 35 s and the blood loss significantly reduced to 71 mg. Notably, it can significantly shorten the healing time of deep burn wound to 17 days by rapidly absorbing wound exudate, promoting collagen deposition and new blood vessels regeneration. Consequently, the composite dressing represents a promising sustained co-delivery system for accelerating burn wound healing.