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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 H 2 O 2 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. Bacteria-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. [Display omitted] [ABSTRACT FROM AUTHOR]

Bacterial infection can cause chronic nonhealing wounds, which may be a great threat to public health. It is highly desirable to develop an injectable wound dressing hydrogel with multifunctions including self‐healing, remodeling, antibacterial, radical scavenging ability, and excellent photothermal properties to promote the regeneration of damaged tissues in clinical practice. In this work, dopamine‐modified gelatin (Gel‐DA) is employed for the first time as a biotemplate for enhancing the biomineralization ability of gelatin to synthesize dopamine‐modified gelatin@Ag nanoparticles (Gel‐DA@Ag NPs). Further, the prepared Gel‐DA@Ag NPs with antioxidant activity and near‐infrared (NIR) laser irradiation synergistic antibacterial behavior are fixed in the guar gum based hydrogels through the formation of borate/didiol bonds to possess remolding, injectable, and self‐healing performance. In addition, the multifunctional hydrogels can completely cover the irregular wound shape to prevent secondary injury. More importantly, these hydrogel platforms under NIR can significantly accelerate wound healing with more skin appendages like hair follicles and blood vessels appearing. Therefore, it is expected that these hydrogels can serve as competitive multifunctional dressings in biomedical field, including bacteria‐derived wound infection and other tissue repair related to reactive oxygen species overexpression. [ABSTRACT FROM AUTHOR]

With the increasingly serious problem of antimicrobial resistance and the lack of clinical response strategies, the development of new antibacterial materials is imminent. Herein, a VIS/NIR co-irradiation photodynamic-photothermal and oxidase-like synergistic antibacterial platform of transition metal sulfide/TiO 2 nanofibers (TMSs/TiO 2 NFs) is proposed to fight bacterial infection. On one hand, three-dimensional (3D) MoS 2 nanoflowers load can quickly capture the photogenerated electrons of two-dimensional (2D) TiO 2 nanofibers, inhibit the recombination of electron-hole pairs and greatly increase the yield of reactive oxygen species (ROS), thereby overcoming the UV sterilization defects of pure TiO 2 , endowing TiO 2 excellent photodynamic antibacterial ability in the long-wavelength region. On other hand, with the combination of MoS 2 and TiO 2 , the photothermal effect of the 3D/2D heterostructure (MoS 2 /TiO 2 NFs) was significantly enhanced and the local temperature rose to above 50 °C in a short time, which was enough to induce the inactivation of bacterial protein, thereby providing an efficient secondary sterilization effect. In addition, MoS 2 /TiO 2 NFs has fascinating oxidase-like activity, which further accelerated the oxidation of physiologically relevant antioxidants in bacteria. In the end, MoS 2 /TiO 2 NFs exerted outstanding antibacterial efficiencies against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) through the synergy of photodynamic-photothermal and oxidase-like performance. Meanwhile, MoS 2 /TiO 2 NFs antibacterial platform effectively accelerated the healing of S. aureus -infected wounds and showed negligible toxicity and hemolysis on normal cells and tissues. Hence, this study contributed an effective alternative strategy for reducing the use of antibiotics, providing new ideas for application of semiconductor nanomaterials in collaborative combination therapy. [Display omitted] • The 3D/2D TMSs/TiO 2 NFs (MoS 2 /TiO 2 NFs) heterojunctions are successfully prepared in situ. • MoS 2 /TiO 2 NFs heterojunctions are demonstrated to increases the yield of ROS. • MoS 2 /TiO 2 NFs show enhanced photodynamic-photothermal and oxidase-like properties. • MoS 2 /TiO 2 NFs process charming sterilization activity. • MoS 2 /TiO 2 NFs antibacterial agent accelerate S. aureus- infected wound healing. [ABSTRACT FROM AUTHOR]