Single-atom silver-borophene hybrid hydrogels for electrically stimulated wound healing: a multifunctional antibacterial platform

Abstract

Chronic wound healing demands next-generation biomaterials that includes antibacterial properties, electrical responsiveness, and tissue-regenerative capabilities. This study presents a multifunctional hydrogel that incorporates single-atom silver (Ag-SA) and two-dimensional borophene nanosheets (BNSs) within a PVA/chitosan matrix (PCAB). The atomically dispersed Ag sites exhibit highly localized bactericidal activity at a silver amount 50 times lower than those in traditional AgNP systems, thus reducing cytotoxicity and hemolysis to less than 5%. Concurrently, borophene nanosheets provide elevated electrical conductivity (0.45 ± 0.02 S cm⁻¹), water retention, and matrix reinforcement, while facilitating real-time responsiveness under low-voltage stimulation (1 V). The PCAB-1 V hydrogel demonstrated robust antibacterial efficacy, eradicating more than 95% of E. coli and S. aureus, while markedly enhancing fibroblast proliferation (184.3 ± 3.6% viability). In vivo investigations utilizing a mouse full-thickness wound model demonstrated expedited wound closure (97.3%) and epithelium regeneration (124.5 μm) by Day 14. Statistical analysis validated substantial enhancements in all performance indicators (p < 0.001). This study emphasizes the synergistic interaction between Ag-SA and borophene, providing a low-toxicity, electroactive hydrogel substrate for enhanced wound care.