Selective Voltammetric Determination of Tartrazine in the Presence of Red 10B by Nanogold-modified Carbon Paste Electrode

A nanogold modified carbon paste electrode (NG-CPE) was fabricated and used as selective voltammetric sensor for determination of Tartrazine in the presence of Red 10B using cyclic voltammetry (CV), differential pulse voltammetry (DPV), and chronoamperometry (CHA). Electrochemical parameters including the diffusion coefficient (D), the electron transfer coefficient (alpha), and the electron transfer number (n) were determined for the oxidation of 'Tartrazine. This modified electrode can be applied to simultaneous determination of Tartrazine and Red 10B, because of considerable decreases of anodic overpotentials for both compounds. After optimizing the experimental conditions, the anodic peak current of Tartrazine was linear to its concentration in the range of 0.05-1.5 mu mol L-1, and the detection limit was 0.017 mu mol L-1 in phosphate buffer solution (PBS) at pH 4.0. The modified electrode has good stability and repeatability. It was applied to the determination of Tartrazine and Red 10B in soft drinks with satisfactory results.