Hydrogen sulfide releasing poly(γ-glutamic acid) biocomposite hydrogel with monitoring, antioxidant, and antibacterial properties for diabetic wound healing

Adverse factors such as high levels of glucose, oxidative stress , inflammation, and bacterial infection impede diabetic wound healing and even worsen wounds. Owing to its outstanding anti-inflammatory and antioxidant properties as well as the potential to promote cell migration and proliferation, hydrogen sulfide(H 2 S) gas therapy is promising for chronic diabetic wound recovery. In this work, a multifunctional poly(γ-glutamic acid)(PGA) hydrogel encapsulated with keratin-based H 2 S donor(KTC), ciprofloxacin(Cip), and anthocyanins(Ant) was developed. The resultant hydrogel was capable of releasing H 2 S, thereby promoting cell proliferation and enhancing anti-inflammation and antioxidant activity . The release of antibiotic Cip was accelerated under a diabetic wound microenvironment, thereby enhancing the antibacterial activity of the hydrogel. The encapsulated Ant could serve as a pH monitor, sensitively indicating wound pH conditions in situ and indirectly reflecting wound infection. In vivo results in diabetic wound healing suggested that PGA/Ant/KTC/Cip hydrogel reduced inflammation and promoted angiogenesis and collagen deposition, thereby accelerating wound healing.