Enhancement of the electrochemical behavior of CuO nanoleaves on MWCNTs/GC composite film modified electrode for determination of norfloxacin

A novel and facile (single-step) method was developed for the synthesis of CuO nanoleaves in the presence of a cationic polyelectrolyte, poly(diallyldimethylammonium chloride) (PDDA) at pH 10.5. The mechanism and self-assembly for the formation of CuO nanoleaves are discussed. The structure and morphology of CuO nanoleaves are characterized by means of Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FESEM) and high resolution transmission electron microscopic (TEM) studies. The CuO/MWCNTs modified glassy carbon (GC) electrode was fabricated via the drop-casting of CuO nanoleaves suspension on MWCNTs/GC surface. In order to investigate the electrochemical behavior of norfloxacin, cyclic voltammetry (CV) and differential pulse voltammetric analysis (DPV) were carried out and compare the oxidation behavior on CuO/MWCNTs/GC, MWCNTs/GC and bare GC. The electrocatalytic oxidation of norfloxacin was studied (pH 7.2) on CuO/MWCNTs/GC electrode and found an irreversible behavior in the range from 0 to +1.1 V with an oxidation peak at 0.91 V in physiological conditions. The quantitative detection of norfloxacin was obtained with a limit of detection of 3.21 × 10−7 M within a linear range from 1 μM to 47.7 μM.