银-氨基乙酸复合膜修饰玻碳电极循环伏安法测定苏丹红Ⅲ

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

摘要: 制备了银-氨基乙酸复合膜修饰玻碳电极,采用循环伏安法研究了苏丹红Ⅲ在修饰电极上的电化学行为。结果表明:在pH 3.0的磷酸盐缓冲溶液中,苏丹红Ⅲ在修饰电极上呈现一对灵敏的氧化还原峰,提出了用循环伏安法测定苏丹红Ⅲ的方法。苏丹红Ⅲ的浓度在3.0×10-7~4.0×10-5mol·L-1范围内与还原峰电流呈线性关系,检出限(3S/N)为9.0×10-8mol·L-1。修饰电极用于调味品中苏丹红Ⅲ的测定,回收率在94.1%~98.5%之间,测定值的相对标准偏差(n=6)在2.2%~4.6%之间。

Abstract: 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%.