Anodically Pretreated Electrodes Using a Nontoxic Reagent: A New Voltammetric Sensing for Selective and Simultaneous Determination of Synthetic Dyes

Abstract

A novel voltammetric electrode based on a screen-printed graphene electrode pretreated by the anodically pretreated process using a nontoxic reagent was first developed. A phosphate buffer solution (0.1 M) at pH 7 was used as a supporting electrolyte for the anodic pretreatment process. After the oxidizing process, the pretreated electrode was used to investigate the electrochemical properties of sunset yellow (SY) and tartrazine (TAR). The well-defined oxidation peaks of SY and TAR were clearly observed at +0.45 and +0.70 V (vs Ag/AgCl), respectively. Under the selected experimental variables, the calibration curves of SY and TAR were obtained in the ranges of 0.01–5.0 μM and 0.1–10.0 μM, with the LOD values being experimentally obtained (S/N = 3) and found to be 10 and 100 nM for SY and TAR, respectively. The developed electrode was successfully applied to the simultaneous determination of SY and TAR in nonalcoholic beverages, with the recovery values being in the range of 97.96%–102.76% and % relative errors are 1.5%–6.99%, which can be accepted. This new finding offers a simple, environmentally friendly process and cost-effectiveness for electrode fabrication. Moreover, this procedure can be considered as an alternative method for the routine analysis of food colorants.