Biocompatible gellan gum/sericin hydrogels containing halloysite@polydopamine nanotubes with hemostasis and photothermal antibacterial properties for promoting infectious wound repair

Skin wounds accompanied by massive bleeding and bacterial infection can be life-threatening and pose a significant challenge to clinical wound management. Herein, we prepared gellan gum/sericin hydrogels containing PDA-encapsulated halloysite nanotubes (halloysite@polydopamine) to achieve fast hemostasis and photothermally antibacterial effects. The morphology and compressive properties of the composite hydrogels were characterized, and the biocompatibility was investigated by hemocompatibility and cytocompatibility tests. The hemostatic properties were further evaluated in the rat liver hemorrhage and tail amputation model. The mechanical performance (compressive strength 353.2 KPa) and the hemostatic effect (30.33 ± 3.68 s in the liver injury model and 28.33 ± 2.35 s in the caudal amputation model) of the composite hydrogel were improved due to the introduction of halloysite@polydopamine. In addition, the composite hydrogel rapidly heated under 808 nm near-infrared (NIR) light irradiation, making the hydrogel extremely effective against E. coli and S. aureus. Furthermore, the wound closure rate, granulation tissue thickness, collagen deposition, and expression of inflammation-associated cytokines (CD68) and angiogenesis-associated cytokines (CD31) were investigated in a rat full-thickness skin defect model infected with S. aureus. All results showed that this multifunctional hydrogel provided better healing effects, suggesting that the composite hydrogel has become a promising alternative for infected wound repair.