Injectable chitosan hydrogels tailored with antibacterial and antioxidant dual functions for regenerative wound healing

Herein, an injectable self-healing hydrogel with inherent antibacterial activity was fabricated based on the dy-namic covalent bond formation between boronic acid and catechol groups in quaternized chitosan as building blocks in conjunct with the in-situ encapsulation of epigallocatechin-3-gallate (EGCG, a green tea derivative). Benefiting from the catechol groups and therapeutic effect of EGCG, the resulting natural-based injectable hydrogels showed excellent antibacterial and antioxidant dual functions in preventing bacterial infection and scavenging radicals. The hydrogels loaded with EGCG also exhibited good biocompatibility along with contact -active antibacterial activity via a "capture and kill" strategy. The dynamic covalent bonding enables shear -thinning delivery of the gels via syringe, followed by rapid self-healing. Additionally, the in vivo wound heal-ing evaluation in a full-thickness skin defect model revealed the appreciable and regenerative wound healing performance of the hydrogels, demonstrating their great potential as novel wound dressings for wound management.