MoS2-functionalized chitosan hydrogel with antibacterial and antioxidant functions promotes healing of infected diabetic wounds

Abstract

Due to high levels of reactive oxygen species (ROS), bacterial infections, and persistent inflammatory responses, the healing of diabetic infected wounds remains challenging. Therefore, diabetic wound dressings face higher demands for antioxidant and antibacterial properties. Additionally, dressings that are injectable, self-healing, and have good adhesion are particularly ideal as they can adapt to irregular wounds and self-repair after external damage. In this study, we designed an injectable, self-healing adhesive composite hydrogel with dual functions of antibacterial and antioxidant properties by functionalizing chitosan (CS) with molybdenum disulfide (MoS₂) and using the Schiff base reaction with the star-shaped eight-arm crosslinker benzaldehyde-terminated polyethylene glycol (POSS-PEG-CHO). This composite hydrogel exhibits excellent tissue adhesion, hemostatic properties, robust mechanical strength, and good cellular compatibility. The incorporation of MoS₂ nanosheets (NS) endows the hydrogel with exceptional photothermal antibacterial effects and effective ROS scavenging capability. MoS₂@Gel demonstrates strong ROS scavenging at the molecular level and superior antibacterial performance under near-infrared light. Moreover, in a diabetic wound infection model, MoS₂@Gel significantly alleviates oxidative stress and bacterial infection during the inflammatory phase, while promoting epithelial tissue regeneration, collagen deposition, and angiogenesis, thereby accelerating the repair of diabetic wounds. Therefore, this composite hydrogel represents a promising and effective strategy for treating diabetic infected wounds.