An electrochemical sensor based on Poly (Eriochrome Black T)/nanoporous fibers modified electrode for Electrocatalytic Determination of Ascorbic Acid

2-hydroxy-1-(1-hydroxy-2-naphthylazo)-6-nitronaphthalene-4-sulfonic acid sodium salt (Eriochrome Black-T, EBT) is a classical azo sulfonic acid dye, which has been often used as the spectroscopic probe for the determination of metal ion and biological molecules [1, 2]. In recent years, the electropolymerization and the biosensing application of its polymer also attract much attention. The electropolymer film coated electrodes are playing an important role in sensor field [3]. In our present investigation, a new modified electrode fabricated from the poly (EBT)/ nanoporous, by cyclic voltammetry that the whole procedures take only several minutes and can be used for quantification of ascorbic acid (AA) in different real samples. The surface and electrochemical characterization of the modified electrode was performed by field emission scanning electron microscopy, chronoamperometry, cyclic voltammetry and differential pulse voltammetry. A significant enhancement in the peak current response of AA was observed accompanied with a negative shift in peak potential at the composite modified electrode compared to the unmodified electrode. Using differential pulse voltammetry, the calibration curves for AA was obtained over the range of 0.15–100mM. The effect of pH, scan rate and concentration of AA were studied in detail. The presented methodology possesses a reliable reproducibility, repeatability and stability 14th Annual Electrochemistry Seminar of Iran Materials and Energy Research Center (MERC), 12- 13 Dec, 2018 23 in biological samples. The proposed electrode was successfully applied for AA determination in pharmaceutical formulations with promising results.