Skin-inspired conductive hydrogels with antibacterial and pro-angiogenic abilities customized for accelerating diabetic wound healing

Intense bacterial infection, long-term inflammatory infiltration, and inadequate vascularization make diabetic wounds non-healing. Endogenous electric fields are the basis of bioelectric signal conduction and have been shown to be the primary signal guiding cell migration and promoting tissue repair. Still, the disorder microenvironment of diabetic wounds may affect the functions of endogenous electric fields. Traditional wound dressings, such as gauzes and bandages, lead to unsatisfactory repair due to their limited infection management and inability to couple with endogenous electrical fields. In this study, we develop the PMQG hydrogel, a multifunctional hydrogel dressing with effective antibacterial properties and good electroactivity, made from acrylic acid, quaternary ammonium chitosan, and MXene nanosheets. Inspired by skin, the PMQG hydrogels have flexible mechanical properties matched to the skin, strong tissue adhesion, broad-spectrum antibacterial activity, and desirable conductivity, which could transmit electrical signals, facilitating cell migration, and thus promoting the process of wound repair. The PMQG hydrogels exhibited good antibacterial properties against Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), and methicillin-resistant S. aureus (MRSA), effectively controlling the infection-induced inflammation. Furthermore, incorporating MXene nanosheets into the hydrogel network enhances its reactive oxygen species scavenging ability and provides biomimetic conductivity. These anti-inflammatory properties, combined with its conductivity, help regulate the microenvironment and rebuild the endogenous electric fields, facilitating cell migration, angiogenesis, and collagen deposition, leading to a remarkable 98% wound closure by day 15 in diabetic rats, thus demonstrating superior efficacy. This novel wound dressing is expected to be an ideal therapeutic strategy for diabetic wound healing.