An Antibacterial and Electroactive Chitosan-Based Dressing with Dual Stimulus-Responsive Drug Delivery for Wound...

Persistent bacterial infections remain a major challenge in wound management. Although drug-loaded wound dressings have gained increasing attention, their therapeutic efficacy is often hindered by uncontrolled drug release and a lack of electrical signal responsiveness. Herein, an antibacterial dressing (CCS-PC) with electroactivity and stimulus-responsive drug release properties was fabricated via electro-assembly, wherein chitosan and ciprofloxacin hydrochloride (CIP) were co-deposited onto polypyrrole (PPy)-coated gauze. The PPy coating endows CCS-PC with excellent electroactivity to restore endogenous electric fields. Notably, benefiting from the pH-responsiveness of chitosan and the positive charge of CIP, CCS-PC exhibits dual-stimuli (pH/voltage) responsive drug release behavior. In vitro studies demonstrate that CCS-PC possesses excellent cytocompatibility, blood compatibility, and hemostatic ability. More importantly, it shows significant inhibitory effects against both E. coli and S. aureus. In a rat bacterial-infected full-thickness skin wound model, CCS-PC accelerates wound healing by drug release responsive to acidic microenvironments and by restoration of endogenous electric fields, particularly in the early stages. Overall, CCS-PC holds promising clinical potential as a material for treating infected wounds.