Copper Pyrovanadate Nanoribbons as Efficient Multienzyme Mimicking Nanozyme for Biosensing Applications

Development of nanozymes with intrinsic multienzyme mimetic activity has attracted tremendous research attention as nanozymes offer several advantages over multimodal natural enzymes and are a key toward multifunctional biomedical applications. Shape-selective ternary metal oxides with multicatalytic sites can be developed as potential multienzyme mimetic nanomaterials taking advantage of the variable valence states of the metal constituents and their synergy along with the added advantage offered by the exposed surface for enhanced catalytic activity. Herein, we have explored the multicatalytic activity of Cu3V2O7(OH)2·2H2O nanoribbons for peroxidase, oxidase, and laccase mimicking activity. The fabrication of Cu3V2O7(OH)2 nanoribbons was performed using the polyol-based hydrothermal pathway, and the choice of precursor metal salts and their molar ratio was found to be instrumental in the shape, size, and phase selective evolution of copper pyrovanadates. The as-synthesized nanoribbons showed excellent peroxidase-like activity with Km value of 0.004 mM for H2O2, which is considerably smaller than those reported for HRP and other nanozymes. The efficient oxidase mimicking behavior of these Cu3V2O7(OH)2 nanoribbons could be used for the colorimetric detection of glutathione with a limit of detection of 0.08 μM. Further, the nanoribbons also showed laccase-mimetic behavior and were used for the colorimetric detection of epinephrine, which is a useful hormone and neurotransmitter.