Nanoenzyme-Reinforced Injectable Hydrogel for Healing Diabetic Wounds Infected with Multidrug Resistant Bacteria.

Abstract

Diabetic wound healing remains a critical challenge due to its vulnerability to multidrug-resistant (MDR) bacterial infection, as well as the hyperglycemic and oxidative wound microenvironment. Herein, an injectable multifunctional hydrogel (FEMI) was developed to simultaneously overcome these hurdles. The FEMI hydrogel was fabricated through a Schiff-based reaction between ε-polylysine (EPL)-coated MnO2 nanosheets (EM) and insulin-loaded self-assembled aldehyde Pluronic F127 (FCHO) micelles. Through a synergistic combination of EPL and "nanoknife-like" MnO2 nanosheets, the FEMI hydrogel exhibited extraordinary antimicrobial capacities against MDR bacteria. The MnO2 nanoenzyme reshaped the hostile oxidative wound microenvironment by decomposing the endogenous H2O2 into O2. Meanwhile, the pH/redox dual-responsive FEMI hydrogel achieved a sustained and spatiotemporal controlled release of insulin to regulate the blood glucose. Our FEMI hydrogel demonstrated an accelerated MDR bacteria-infected diabetic wound healing in vivo and represents a versatile strategy for healing a broad range of tissue damages caused by diabetes.