Heterostructure of Metal Oxides Integrated on a GCE for Estimation of H2O2 Capacity in Milk and Fruit Juice Samples

Abstract

High levels of H2O2 in food can lead to oxidative stress. Which has been linked to a number of neurological diseases. Hence, its detection in beverages is essential. However, a complicated structure of the reaction medium of H2O2 makes the detection procedure very difficult. For this reason, sensitive strategic methods are required. In this study, quantification of H2O2 in milk and apple juice has been obtained via the electrochemical sensing platform based on GCE/SiO-CeONPs. Scanning Electron Microscopy (SEM), Cyclic voltammetry(CV), and electron impedance spectroscopy(EIS) were employed to characterize the composite. The kinetics investigation of the sensor with H2O2 revealed an a quasi-reversible one -electron adsorption process. Under optimized conditions, the Differential Pulse Voltammetry (DPV) in 0.1 M Phosphate buffer (PB) pH 5.5 of the H2O2 displayed a peak at 0.13 V vs. Ag/AgCl with the detection limits of 0.0004 µM, linearity range of 0.01–0.08 µM. The observed LOD values of this method for real samples were calculated to be 0.006 µM and 0.007 µM with LOQ of 0.02 µM for milk and apple juice, respectively. The recovery of the analyte was from 92 to 99%. Furthermore, due to good selectivity and stability, the benefit of this sensor is its applicability in multiple fields.