Low Cost, Sensitive and Selective Chronoamperometric Determination of Vanillin at a Disposable Poly(Eriochrome Black T)/Pencil Graphite Electrode

In this study, low cost, sensitive and selective chronoamperometric determination of vanillin (VNL) is firstly achieved by using a disposable poly(Eriochrome Black T) modified pencil graphite electrode (poly(EBT)/PGE). Electro-oxidation behavior of 1.0 mM VNL was investigated at both poly(EBT)/PGE and PGE by the cyclic voltammetry (CV) method. CV measurements showed that oxidation current of VNL at poly (EBT)/PGE was much higher than the bare one. Furthermore, the pH effect on electro-oxidation current of VNL was tested at different pH values (2.0-8.0) of Britton Robinson Buffer solution (BRBS) for poly(EBT)/PGE and the highest current was obtained at pH 7.0 BRBS. Significant analytical parameters such as linear response range (LRR), limit of detection (LOD), and sensitivity were found as 0.050-10.0 µM, 0.013 µM and 5355 µA mM-1 cm-2, respectively. The fabricated sensor was tested on a VNL-containing sample (VNL content: 3.0%) and the result (3.04% ±0.01) obtained from the applicability study showed that the proposed sensor enables the determination of VNL with high accuracy and precision. © 2020 Authors. All rights reserved.