Fabrication of copper oxide nanoparticles modified carbon paste electrode and its application in simultaneous electroanalysis of guanine, adenine and thymine

Copper oxide nanoparticles (CuO NPs) were synthesized by the effortless co-precipitation method. The morphology, structure and optical characterization were investigated by scanning electron microscopy (SEM), X-ray diffraction, Fourier transform-infrared, (FTIR) and Ultra-Violet (UV) spectroscopy. The results specified that the resultant CuO NPs possess an average diameter of 12 nm and were effectively deposited on carbon paste electrode. The analytical performance of this novel CuO NPs modified carbon paste electrode (CuO NPsMCPE) was demonstrated the interference-free determination of guanine (G), adenine (A), and thymine (T) concurrently in a ternary mixture with phosphate buffer (PB) solution. The electrochemical investigation was carried out using cyclic voltammetry (CV), differential pulse voltammetry (DPV) and electrochemical impedance (EIS) spectroscopy demonstrated the potent and persistent electro-oxidation performance followed by well-separated oxidation peaks towards the detection of G, A and T. Besides this, the sensor manifested a wide linear range of 1-80 μM, 1-80 μM and 1-210 μM with the detection limit of 0.687, 0.472, and 0.111 μM for G, A and T correspondingly. The advantages of the deliberated sensor encompass good electrocatalytic activity, fast electron transfer rate, high accessible surface area and antifouling features towards the estimation and low investment of fabrication.