A simple yet effective hydrogel dressing for advanced microenvironmental management of diabetic wounds with intrinsic regulation

Diabetic wounds are challenging to heal due to high glucose levels, and oxidative stress, impaired immune response and delayed angiogenesis. Hydrogel dressings capable of adapting and improving multiple microenvironments have broad prospects for application in clinical diabetes wound healing. In this study, we developed a photocrosslinked chitosan hydrogel using the antioxidant molecule “lipoic acid”, eliminating the need for additional photoinitiators. The obtained hydrogel exhibited respectable adhesion (adhesion strengths to iron, wood and skin are 0.045 MPa, 0.049 MPa and 0.041 MPa, respectively), photo-induced self-healing, and responsiveness to pH, H2O2 and glucose. Notably, as compared to conventional injectable methacrylated chitosan hydrogel, LAMC hydrogels displayed the abilities to regulate the wound environment, such as reducing oxidative stress, blood sugar levels, and pH, and creating a favorable microenvironment for wound healing. Exosome-loaded LAMC hydrogels enabled targeted exosome release based on glucose concentration, pH, and H2O2 to promote angiogenesis and accelerate healing. Our study offers a novel method for preparing injectable chitosan hydrogels and introduces a new strategy for developing drug-delivery systems that effectively promote diabetic wound healing, potentially transforming current therapeutic approaches.