Cyclic Voltammetric Determination of Sudan Red Ⅲ with the Composite Film Modified Glassy Carbon Electrode of Ag-Aminoacetic Acid

Composite film of silver and aminoacetic acid modified glassy carbon electrode was prepared. Electrochemical property of the modified electrode was studied by cyclic voltammetry. It was found that Sudan red Ⅲ showed an oxidation peak in PBS of pH 3.0, and based on this finding, a selective method for determination of Sudan red Ⅲ by cyclic voltammetry was proposed. Linear relationship between values of peak current and concentration of Sudan red Ⅲ was ranged from 3.0×10-7 to 4.0×10-5mol·L-1, with detection limit (3S/N) of 9.0×10-8mol·L-1. The proposed method was used in the determination of Sudan red Ⅲ in sauce samples, giving values of recovery in the range of 94.1%-98.5% and RSD′s (n=6) in the range of 2.2%-4.6%.