Copper oxide-polyaniline nanofiber modified fluorine doped tin oxide (FTO) electrode as non-enzymatic glucose sensor

In this study, copper oxide-polyaniline nanofiber modified fluorine doped tin oxide (CuO/PANI-NF/FTO) electrode is introduced as a non-enzymatic glucose sensor. PANI-NFs were polymerized by a chemical method and through a cellulose ester membrane. These fibers were dip coated on FTO and then CuO particles were deposited on PANI-NFs by the electrodeposition method (CuO/PANI-NF). The morphology and structure were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS) and Fourier transform infrared (FTIR). The electrochemical response of the proposed electrode in presence of glucose was investigated in 0.1 M NaOH. In addition, comparing the performance of the CuO/PANI-NF/FTO with PANI-NF/FTO and the bare FTO indicated its superiority over the last two. The chronoamperometry (CA) linear range of the proposed sensor was between 0.25 mu M to 4.6 mM with the detection limit of 0.24 mu M (S/N = 3). The interference effect of some important species such as ascorbic acid, dopamine, uric acid, urea and sodium chloride was examined and no considerable interfering effect was observed. The repeatability and reproducibility of the electrode for glucose detection were 4.9 and 3.6%, respectively. Finally, the electrode stability was investigated and after 11 days, the electrode showed similar to 90% of its initial signal. All results proved the proposed electrode excellence for non-enzymatic glucose sensing due to its simplicity, ease of preparation, wide linear range, appropriate selectivity and stability. (C) 2018 Elsevier B.V. All rights reserved.