Dual enzyme-like properties of silver nanoparticles decorated AgWO nanorods and its application for HO and glucose sensing.

The facile one-pot hydrothermal synthesis of silver nanoparticles decorated silver tungstate nanorods (Ag@AgWO NRs) and their catalytic activities similar to those of natural enzymes catalase and peroxidase were reported. The Ag@AgWO NRs could catalyze the decomposition reaction of HO into water and oxygen besides catalyzing the reduction of HO into water in the presence of peroxidase substrates. Spectrophotometric and electrochemical methods were used to investigate the pH-dependent dual enzyme mimics exhibited by Ag@AgWO NRs. The Ag@AgWO NRs showed a lower Km value when compared to the natural horseradish peroxidase enzyme showing the stronger affinity for hydrogen peroxide and TMB. The peroxidase-like property of the synthesized Ag@AgWO NRs was exploited to develop a HO sensor with a broad linear range and low detection limit. Thus, a wide linear range of 45.4 μM- 2.38 mM and a low detection limit of 5.4 μM was obtained by spectrophotometry while a wide linear range of 62.34 μM- 2.4 mM and a low detection limit of 6.25 μM was obtained by amperometry for HO. Further, the detection method was extended for the detection of glucose with a wide linear range of 27.7 μM- 0.33 mM and a low detection limit of 2.6 μM.