A spatiotemporal release platform based on pH/ROS stimuli-responsive hydrogel in wound repairing

Fabricating injectable hydrogel with multifunctions that matchs the highly ordered healing process of skin regeneration has greatly desired in treatment of chronic diabetic wounds. Herein, a pH/reactive oxygen species (ROS) dual responsive injectable glycopeptide hydrogel based on phenylboronic acid-grafted oxidized dextran and caffeic acid-grafted ε-polylysine was constructed, which exhibited inherent antibacterial and antioxidant capacities. The mangiferin (MF) with the ability to promote angiogenesis was encapsulated into pH-responsive micelles (MIC). Subsequently, diclofenac sodium (DS) with anti-inflammatory activities and MIC@MF were embedded into the hydrogel. The hydrogel possessed good biodegradability, stable rheological property and self-healing ability, and could realize the spatiotemporal delivery of DS and MF. The in vitro and in vivo data showed that the hydrogel was biocompatible with effective anti-infection, anti-oxidation and anti-inflammation at early stages, then further promoted angiogenesis and accelerated wound repairing. Collectively, this novel glycopeptide hydrogel provides a facile and effective strategy for chronic diabetic wound repairing.