Manganese single-atom catalysts for catalytic-photothermal synergistic anti-infected therapy

Bacteria-infected inflammation caused by the pathogenic bacteria have become a serious threat to patients. Moreover, multi-drug resistant infections due to the prescription of empiric antibiotics is still a big concern worldwide. Herein, spherical mesoporous manganese single atom catalysts (Mn SACs) are developed for photothermal-catalytic antibacterial therapy based on Pluronic F127 and dopamine hydrochloride using nano-emulsion assembly approach. The significant peroxidase-like catalytic activity of Mn SACs could generate abundant •OH in the presence of H₂O₂. In addition, the catalytic activity of the Mn SACs was seen to be further enhanced with the assistance of its photothermal properties. In vitro antibacterial experiments confirmed that the synergetic catalyze therapy and photothermal therapy have better antibacterial effect against typical Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus). The cytotoxicity assay illustrated great biocompatibility of the Mn SACs, providing a possibility for its in vivo therapy application. Remarkably, the healing rate and immune fluorescence of E. coli infected wounds indicated that the synergetic treated group had better anti-infection response. This was concluded from alleviating the inflammation and enhancing palingenetic angiogenesis. In summary, this study provides a novel approach for synthesis of spherical mesoporous single-atom catalysts, which was used as an anti-infection agent and could be further explored in relevant biomedicine field.