Enzyme-free selective determination of H2O2 and glucose using functionalized CuNP-modified graphite electrode in room temperature ionic liquid medium

Abstract

A novel enzyme-free modified electrode constructed by electropolymerization of L-cysteine on a graphite electrode, followed by electrodeposition of copper nanoparticles using ionic liquid as a green electrolyte. The modified electrode exhibits an excellent electrocatalytic activity towards the oxidation of hydrogen peroxide (H₂O₂) and glucose at a reduced overpotential of 0 V and +0.35 V, respectively. The immobilization of copper nanoparticle encapsulated by polycysteine (PC) formed on the electrode was confirmed by Fourier transform infrared (FT-IR) spectroscopy, Raman spectra, X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM) and atomic force microscopy (AFM) studies. The determination of H₂O₂ and glucose with the modified electrode shows the advantages of ease of preparation, high sensitivity, good selectivity and stability. The practical application of the modified electrode for selective detection of H₂O₂ and glucose has been evaluated by analyzing the real samples of stain remover solutions and human urine samples to determine H₂O₂ and glucose, respectively.