Chondroitin sulfate/silk fibroin hydrogel incorporating graphene oxide quantum dots with photothermal-effect promotes type H vessel-related wound healing

Chronic wounds with bacterial infection present formidable clinical challenges. In this study, a versatile hydrogel dressing with antibacterial and angiogenic activity composite of silk fibroin (SF), chondroitin sulfate (CS), and graphene oxide quantum dots (GOQDs) is fabricated. GOQDs@SF/CS (GSC) hydrogel is rapidly formed through the enzyme catalytic action of horseradish peroxidase. With the incorporation of GOQDs both gelation speed and mechanical properties have been enhanced, and the photothermal characteristics of GOQDs in GSC hydrogel enabling bacterial killing through photothermal treatment (PTT) at ~51 °C. In vitro studies show that the GSC hydrogels demonstrate excellent antibacterial performance and induces type H vessel differentiation of endothelial cells via the activated ERK1/2 signaling pathway and upregulated SLIT3 expression. While in vivo results show that the hydrogel significantly promotes type H vessels formation, which related to the collagen deposition, epithelialization and, ultimately accelerating the regeneration of infected skin defects. Collectively, this multifunctional GSC hydrogel, with dual action of antibacterial efficacy and angiogenesis promotion, emerges as an innovative skin dressing with potential for advancing in infected wound healing.