Mechanism Investigation and Electrochemical Assay of Dextromethorphan based on (CuO-CNPs) Composite

Abstract

A novel type of modified electrode was developed to elucidate how dextromethorphan (DM) undergoes oxidation and to measure it with very high sensitivity using voltammetry. To make the sensor, a mixture containing copper oxide and carbon nanoparticles (CuO/CNPs) was prepared and then deposited as a thin layer on the surface of a glassy carbon electrode (GCE). The CuO nanoparticles were synthesized via a straightforward and environmentally friendly hydrothermal method. Comprehensive characterization using scanning electron microscopy and electrochemical impedance spectroscopy confirmed the successful fabrication and enhanced properties of the CuO/CNPs/GCE. The synergistic combination of the large surface area of the CNPs and the superior electrocatalytic activity of the CuO NPs resulted in a remarkable amplification of the DM oxidation signal. Compared to a bare GCE, the modified electrode showed more than 30 times higher peak current, and the oxidation overpotential was reduced by 70 mV, which means the reaction happens more easily. After carefully adjusting the experimental conditions, the way DM oxidizes at CuO/CNPs/GCE was examined. The sensor turned out to be very effective for measuring DM, with a linear response in the concentration range of 0.07-20.0 µM and a detection limit as low as 53 nM. To see if it works in real-life situations, the CuO/CNPs/GCE was also used to measure DM in commercial pharmaceutical products. The results were accurate and reliable, showing that this method can be useful for practical analysis.