Voltammetric Determination of Carmoisine in Soft Drinks

Resumo

A voltammetric study of the electrochemical behavior of red food azo dye Carmoisine on a glassy carbon electrode (GCE) is performed. The influence of various factors on the cathode signal of the dye is shown: pH and values of accumulation time and potential sweep rate. The operating conditions of Carmoisine identification in model media are selected: pH = 1.65, E_acc = –0.1 V, t_acc = 10 s, W = 100 mV/s. A linear dependence of the electrolytic reduction current of the dye on its concentration at –0.15 V is observed within 0.05–0.5 mg/L; detection limit of Carmoisine is 0.02 mg/L. A comparative determination of Carmoisine in soft drinks is performed by voltammetric and spectrophotometric methods.