Voltammetric determination of sunset yellow using a nanostructure modified electrode in food sample

In this study, NiO nanoparticles and 1-methyl-3-butyl-imidazolinium bromide as ionic liquid carbon paste electrode (NiO/NP/IL/CPE) were fabricated to determine sunset yellow (SY) in soda water and orange juice. In the first step, NiO/NP was characterized by transmission electron microscopy (TEM). The electro-oxidation of (SY) occurred at a potential about 0.7 V, which was much better in comparison with bare carbon paste electrode in phosphate buffer (pH=8) at the surface of the modified electrode. Other electrochemical techniques were also investigated including cyclic voltammetry, differential pulse voltammetry (DPV) and chronoamperometry at NiO/NP/IL/CPE. At optimized conditions for SY analysis, DPV peak currents of SY showed a wide linear dynamic ranging from 0.006 to 350 μM with a good detection limit of 4.0 nM. Finally, the proposed sensor was used for determination of sunset yellow in real samples with good selectivity and high sensitivity.