Determination of patent blue V (E131) at a Nafion-modified glassy carbon electrode

Patent Blue V was determined in aqueous solutions at a Nafion-coated glassy carbon electrode using a DPV technique. Preliminary cyclic voltammetric studies allowed to choose the most sensitive peak and a further DPV study allowed determining the analyte in the 10-7-10-6 M range, with a detection limit equal to 7.6×10-8 M, two orders of magnitude lower than at a bare GC electrode. The modified electrode was applied to the analysis of matrices of alimentary concern in presence of tartrazine. Thanks to the method high sensitivity, very diluted samples can be analyzed minimizing the matrix effects.