Antibacterial and antioxidant bifunctional hydrogel based on hyaluronic acid complex MoS2-dithiothreitol nanozyme for treatment of infected wounds

Abstract

Wound repair is a complex physiological process that often leads to bacterial infections, which significantly threaten human health. Therefore, developing wound-healing materials that promote healing and prevent bacterial infections is crucial. In this study, the coordination interaction between sulfhydryl groups on dithiothreitol (DTT) and MoS2 nanosheets is investigated to synthesize a MoS2-DTT nanozyme with photothermal properties and an improved free-radical scavenging ability. Double-bond-modified hyaluronic acid is used as a monomer and is cross-linked with a PF127-DA agent. PHMoD is prepared in coordination with MoS2-dithiothreitol as the functional component. This hydrogel exhibits antioxidant and antibacterial properties, attributed to the catalytic activity of catalase-like enzymes and photothermal effects. Under the NIR, it exhibits potent antibacterial effects against gram-positive (Staphylococcus aureus) and gram-negative bacteria (Escherichia coli), achieving bactericidal rates of 99.76% and 99.42%, respectively. Furthermore, the hydrogel exhibits remarkable ROS scavenging and antioxidant capabilities, effectively countering oxidative stress in L929 cells. Remarkably, in an animal model, wounds treated with the PHMoD(2.0) and NIR laser heal the fastest, sealing completely within 10 d. These results indicate the unique biocompatibility and bifunctionality of the PHMoD, which make it a promising material for wound-healing applications.