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 x 10(-7) to 7.5 x 10(-5) M, r = 0.9967), detection limit ( 2.0 x 10(-7) M) and reproducibility (RSD = 4.6%, n=10, for 2.0 x 10(-5) M Sudan I).