Construction of a photothermal hydrogel platform with two-dimensional PEG@zirconium-ferrocene MOF nanozymes for rapid tissue repair of bacteria-infected wounds

Abstract

Because of increasing antibiotic resistance, careful construction of an efficient phototherm-nanozyme-hydrogel synergistic antibacterial platform is imperative for the treatment of bacteria-infected wounds. In this study, a carrageenan-based hydrogel embedded with polyethylene glycol dicarboxylic acid (COOH-PEG-COOH)-functionalized zirconium-ferrocene metal-organic frames nanosheets (PEG@Zr-Fc MOF hydrogel) was successfully constructed through COOH-PEG-COOH modification and physical assembly. The PEG@Zr-Fc MOF hydrogel could capture Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacteria through reactive oxygen species (ROS) destruction and kill some bacteria by disintegration of H2O2 into toxic hydroxyl radicals (•OH). Significantly, by introducing the photothermal performance of the PEG@Zr-Fc MOF hydrogel, the catalytic activity of the target material could be improved to achieve a synergistic sterilization effect. The wound infection model experiment confirmed that the PEG@Zr-Fc MOF hydrogel had powerful bactericidal activity and could achieve a rapid tissue repair effect. More importantly, the PEG@Zr-Fc MOF hydrogel had negligible biological toxicity and reduced the risk of inflammation. This study reveals that phototherm-nanozyme-hydrogel synergy holds great potential for bacterial wound infection therapy. Additionally, this is the first study to use two-dimensional MOF nanozymes in combination with hydrogel for antimicrobial therapy. Statement of significanceBacteria-infected wound is one of the serious threats to public health, and this topic has attracted tremendous attention worldwide in recent decades. Although numerous traditional therapeutic strategies that depend on antibiotics have been developed and applied for treating bacteria-infected wound disease, the effect of wound treatment is becoming increasingly unsatisfactory due to bacterial resistance. The present study provides a feasible method to treat bacterial wound infection by constructing a carrageenan-based hydrogel embedded with polyethylene glycol dicarboxylic acid (COOH-PEG-COOH) functionalized zirconium-ferrocene metal organic frame nanosheets (PEG@Zr-Fc MOF hydrogel). The experiments with the wound infection model confirmed that the PEG@Zr-Fc MOF hydrogel had powerful bactericidal activity and could achieve a rapid tissue repair. This strategy provides a promising avenue to further accelerate the development of antibacterial therapy in biomedical fields.