A Facile Electrochemical Sensor Based on NiO-ZnO/MWCNT-COOH Modified GCE for Simultaneous Quantification of Imatinib and Itraconazole

Imatinib (IMA) is frequently used for chronic myeloid leukemia (CML) in clinical treatment. Itraconazole (ITZ), as a fungal antibiotic, is often combined with IMA to decrease the complications of CML. However, ITZ can affect the blood concentration of IMA and cause a series of side effects. Hence, it is necessary to develop a fast and sensitive method to simultaneously detect IMA and ITZ in the course of patient's treatment. Herein, a simple modified glassy carbon electrode with carboxylated multiwalled carbon nanotubes (MWCNTs-COOH) and NiO-ZnO composite (NiO-ZnO/MWCNT-COOH/GCE) is reported for simultaneous determination of IMA and ITZ for the first time. The MWCNTs-COOH with tubular structure show good electrical conductivity, meanwhile NiO-ZnO composite with p-n junction improves the effective electrode surface area and exhibits an excellent absorption to analyte. The prepared materials were characterized by scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), raman spectroscopy and fourier transform infrared spectroscopy (FTIR). Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were applied to investigate the electron transfer kinetics of the modified electrode. Under the optimal experimental conditions, electrochemical behaviors of IMA and ITZ were investigated by differential pulse voltammetry (DPV) in B-R buffer solution. The oxidation peak current of ITZ was linearly related to the concentration from 0.025 to 2.2 μM with a low detection limit of 4.1 nM (S/N = 3) and a good sensitivity of 2.64 μA μM −1 cm −2 . The linearity range of IMA was 0.015–2.0 μM with a LOD of 2.4 nM (S/N = 3) and a sensitivity of 9.64 μA μM −1 cm −2 . The proposed sensor was successfully employed to detect IMA and ITZ in human serum and urine samples with satisfactory results.