Nanozymes for Antimicrobes: Precision Biocide

Nanozymes have been used to dealing with microbes and remarkable advances have been made in various areas. Nanozymes with peroxidase-activity such as CeO2 nanoparticles are used for colorimetric sensing of bacteria when integrated with detection antibody, which is much more rapid and lower-cost than traditional methods. Oxidase-mimic nanozymes such as Au nanoparticles (AuNP) are able to generate reactive oxide species (ROS) for killing bacteria. Plenty of nanozymes with peroxidase-activity, such as magnetic iron oxide, grapheme quantum dots have been used for combating bacteria, biofilms as well as practical wound disinfection and healing, through catalyzing H2O2 into highly toxic hydroxyl radical that can degrade the biofilm matrix and effectively kill the bacteria. Recently, a new generation of hybrid nanozymes, such as Au nanoparticles-graphitic carbon nitride (Au/g-C3N4), graphene quantum dot–Ag nanoparticles (GQD/AgNP), has been constructed with synergistically improved catalytic efficiency for more outstanding bactericidal performance. Apart from medical applications, nanozymes also have been used in industrial area. V2O5 nanowires and CeO2−x nanorods acting like natural haloperoxidase can prevent marine biofouling through catalyzing the oxidation of bromide ions with hydrogen peroxide to hypobromous acid, which interferes with the quorum sensing system of bacteria for thwarting biofilm development. Nanozymes are stable, biocompatible and not causing drug resistance, having great potential to be the substitution of conventional biocides.