Electrochemical Evaluation of Vitamin B2 through a Portable Electrochemical Sensor Based on Binary Transition Metal Oxide in Various Biological and Vegetable Samples

Abstract

Fabrication & electrochemical evaluation of Vitamin B2-riboflavin (RF) sensor based on binary transition metal oxide (ZnO-MnO) core–shell nanocomposites (CSNs) on the surface of the glassy carbon electrode (GCE). Firstly, ZnO-MnO core–shell nanocomposites are attained through a one-step hydrothermal synthesis route using zinc acetate and manganese acetate as precursors where ZnO act as a core and MnO formed as a shell. As synthesized binary transition metal oxide-based composite is scrutinized through various physicochemical techniques thereby demonstrating excellent physiochemical features. ZnO-MnO/GCE composite delivers synergistic features of improving the electrochemical properties towards detection of Riboflavin (RF) at an operational voltage of 0.42 V, with the increased active sites because of its structural morphology along with high surface areas. ZnO-MnO/GCE is examined through electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), differential pulse voltammetry (DPV), and linear sweep voltammetry (LSV). Furthermore, ZnO-MnO/GCE shows a remarkable kinetic transfer rate and superior electron transfer rate over other modified electrodes. It also exemplifies a wider linear range (0.05–1102 μM), with Nanomolar level detection (LOD) of 13 nM aided with a sensitivity of 0.3746 μA μM−1 cm−2, respectively. The proposed ZnO-MnO/GCE sensor demonstrates excellent selectivity over the presence of co-interfering species exquisite repeatability, reproducibility, and stability. Further, the real-time monitoring analysis exemplifies excellent recovery percentages from 96.95–99.61% for various biological and vegetable samples.