Synthesis of Polyaniline Nanofibers for Non-enzymatic Glucose Sensor

Considering the intrinsic flaws of insufficient stability and fair repeatability for enzyme based biosensors, one moves interest to develop new electrochemical glucose sensors without using any bio-enzyme, namely non-enzymatic sensors. In this study, copper oxide particles modified polyaniline nanofibers (PANI-NF) were deposited on FTO electrode and used as a non-enzymatic sensor for glucose. PANI-NFs were polymerized by a chemical method and through membrane cellulose ester. These fibers were dip coated on FTO and then copper oxide cubic particles was deposited on PANI-NFs by electrodeposition method. The morphology and structure of CuO/PANI-NF composite was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS) and Fourier transform infrared (FT-IR). The electrochemical response of the proposed electrode in presence of glucose was investigated in various pHs, which the best result was obtained in 0.1 M NaOH. Also the performance of this electrode for glucose detection was compared with bare FTO and PANINF/ FTO, which its performance was very better. The linear range of the proposed sensor was studied by chronoamperometry, which was between 0.7 μM to 2.17 mM. The interference effect of some important species (uric acid, ascorbic acid, dopamine, sodium and chloride ions) was examined, which no considerable interfering effect was observed. The repeatability and reproducibility of the electrode were 4.9 and 3.6%, respectively. Finally, the electrode stability was investigated and after 10 days the electrode showed ~90% of the its initial efficiency. According to simplicity, ease of preparation, wide linear rang, good selectivity and stability the proposed electrode can be used as a non-enzymatic glucose sensor.