Electrochemical Determination of Trace Sudan I Contamination in Chili Powder at Carbon Nanotube Modified Electrodes

We have developed a simple, convenient and inexpensive voltammetric method for determining trace Sudan I contamination in chili powder, based on the catalyzed electrochemical reduction of Sudan I at the carbon nanotube modified electrode. Under optimized conditions, the method exhibited acceptable analytical performance in terms of linearity (over the concentration range 6.0×10–7 to 7.5×10–5 M, r = 0.9967), detection limit (2.0×10–7 M) and reproducibility (RSD = 4.6%, n=10, for 2.0×10–5 M Sudan I).