Nanozymes with reductase-like activities: antioxidant properties and electrochemical behavior

Nanozymes (NZs) as stable cost-effective mimics of natural enzymes may be promising catalysts in food and environmental biotechnology, biosensors, alternative energy and medicine. The majority of known NZs are mimetics of oxidoreductases, although there are only limited data regarding mimetics of reductases. In the present research, a number of metal-based NZs were synthesized via chemical methods and screened for their antioxidant ability in solution. The most effective reductase-like Zn/Cd/Cu NZ was characterized in detail. Its antioxidant properties in comparison with several food products and Trolox, as well as substrate specificity, size and composition were studied. Zn/Cd/Cu NZ was shown to mimic preferentially selenite reductase. The amperometric sensor was constructed possessing a high sensitivity (1700 A M-1 m(-2)) and a broad linear range (16-1000 mu M) for selenite ions. The possibility to apply the fabricated sensor for selenite determination in commercial mineral water has been demonstrated.

Automated summary

Nanozymes, as stable and cost-effective mimics of natural enzymes, have promising applications in food and environmental biotechnology, biosensors, alternative energy, and medicine. This research focused on the synthesis of metal-based Nanozymes via chemical methods and their antioxidant ability in solution. The most effective reductase-like Zn/Cd/Cu Nanozyme was characterized and shown to mimic selenite reductase. Additionally, an amperometric sensor with high sensitivity and a broad linear range for selenite ions was successfully constructed.