Tannic acid-modified MoS2/silk fibroin hydrogel photothermal antibacterial synergistic macrophage M2 polarization regulation for the treatment of diabetic ulcers

Diabetic ulcer treatment is complicated by bacterial infections and immune microenvironment dysregulation. This study developed a multifunctional composite hydrogel by non-covalently functionalizing molybdenum disulfide with tannic acid and integrating it with silk fibroin. The resulting hydrogel demonstrates superior dispersion and photothermal properties, reaching 65.1 °C under near-infrared irradiation while minimizing mechanical damage to host cells. In vitro results confirm significant synergistic photothermal bactericidal effects against E. coli and S. aureus. Furthermore, the hydrogel remodels the immune microenvironment by downregulating inflammatory factors (TNF-α, IL-6) and upregulating M2 macrophage markers (CD206, IL-10). The incorporation of SF further improves biocompatibility and promotes fibroblast migration and proliferation. This TA-MoS2-SF hydrogel provides a promising ‘antibacterial-immunomodulatory-repair’ strategy for clinical DU management.