Near-Infrared Light Enhanced Peroxidase-Like Activity of PEGylated Palladium Nanozyme for Highly Efficient Biofilm Eradication

The overall eradication of biofilm-mode growing bacteria holds significant key to the answer of a series of infection-related health problems. However, the extracellular matrix of bacteria biofilms disables the traditional antimicrobials and, more unfortunately, hampers the development of the anti-infectious alternatives. Therefore, highly effective antimicrobial agents are an urgent need for biofilm-infection control. Herein, a PEGylated palladium nanozyme (Pd-PEG) with peroxidase (POD)-like activity for highly efficient biofilm infection control is reported. Pd-PEG also shows the intrinsic photothermal effect as well as near-infrared (NIR) light-enhanced POD-like activity in the acidic environment, thereby massively destroying the biofilm matrix and killing the adhering bacteria. Importantly, the antimicrobial mechanism of the synergistic treatment based on Pd-PEG+H₂O₂+NIR combination was disclosed. In vitro and in vivo results illustrated the designed Pd-PEG+H₂O₂ +NIR treatment reagent possessed outstanding antibacterial and biofilms elimination effects with negligible biotoxicity. This work hopefully facilitates the development of metal-based nanozymes in biofilm related infectious diseases.