Bimetal phenolic networks-based alginate cryogel for rapid hemostasis and photothermal enhanced bimetallic chemodynamic therapy of wound infection

Fe3+-based metal-phenolic networks (MPNs) have been employed for anti-bacterial photothermal therapy (PTT) enhanced chemodynamic therapy (CDT) owing to their good photothermal properties and Fenton catalytic reactivity. However, their application in anti-bacterial therapy and wound healing was seriously limited by the lack of Fenton reaction efficiency and wound-healing-promoting capabilities. To address this challenge, we developed a sodium alginate (SA)-based cryogel (STCF) containing Fe3+/Cu2+-based bimetallic MPNs. The STCF cryogel was fabricated by co-crosslinking tannic acid (TA) and SA with both Fe3+ and Cu2+, followed by lyophilization of the formed hydrogel. The integrated bimetallic MPNs could endow it with synergistic PTT/CDT. Additionally, the released Cu2+ could promote angiogenesis and contribute to tissue regeneration. In vitro anti-bacterial assays demonstrated its synergistic bactericidal efficacy, while in vivo hemostasis models and infected wound model proved its good hemostatic, anti-bacterial, and wound-healing-promoting effects. Therefore, through integrating bimetallic MPNs into the STCF cryogel, our study proposed a novel strategy to explore multifunctional wound dressings for treating infected wounds, which overcomes the challenges in wound care and infection management.