Optimizing Colorimetric Assay Based on V2O5 Nanozymes for Sensitive Detection of H2O2 and Glucose

Nanozyme-based chemical sensing is a rapidly emerging field of research. Herein, a simple colorimetric assay for the detection of hydrogen peroxide and glucose based on the peroxidase-like activity of V2O5nanozymes has been established. In this assay, the effects of pH, substrate, nanozyme concentrations and buffer solution have been investigated. It was found that compared with 3,3′,5,5′-tetramethylbenzidine (TMB), the enzyme substrateo-phenylenediamine (OPD) seriously interfered with the H2O2detection. Under the optimal reaction conditions, the resulting sensor displayed a good response to H2O2with a linear range of 1 to 500 μM, and a detection limit of 1 μM at a signal-to-noise ratio of 3. A linear correlation was established between absorbance intensity and concentration of glucose from 10 to 2000 μM, with a detection limit of 10 μM. The current work presents a simple, cheap, more convenient, sensitive, and easy handling colorimetric assay.Keywords:V2O5nanozymes;variation;substrates;H2O2;glucose