CuO nanoparticles as haloperoxidase-mimics: Chloride-accelerated heterogeneous Cu-Fenton chemistry for H2O2 and glucose sensing

•CuO nanoparticles act as haloperoxidase mimics.•CuO nanoparticle haloperoxidase mimics can be used to quantify H2O2 and glucose.•CuO nanoparticles halogenate bacterial quorum sensing molecules in biofilms. CuO nanoparticles (CuO NPs) were demonstrated as a novel nanoenzyme, i.e., haloperoxidase mimic, which catalyzes the oxidation of halide ions to form reactive halogen species (RHS). Two functions of CuO NPs have been demonstrated in the work. First, RHS halogenate bacterial signaling molecules, thus preventing biofilm formation. Second, CuO is used in sensitive colorimetric assays for H2O2 and glucose.