基于阴离子表面活性剂增敏效应的孔雀石绿伏安检测

Voltammetric Determination of Malachite Green Based on the Enhancement Effect of Anionic Surfactant

基于阴离子表面活性剂十二烷基苯磺酸（SDBS）的增敏效应,建立了一种测定孔雀石绿（MG）的电化学新方法.实验发现,在pH 6.5的磷酸盐缓冲溶液中,低浓度的SDBS存在,使MG在碳糊电极上的氧化峰电流显著增大,表明SDBS对MG的测定具有明显的增敏效应.优化了支持电解质、表面活性剂种类、SDBS的浓度、富集时间等各项实验参数,在此基础上,建立了一种简便、灵敏的测定MG的电化学新方法.氧化峰电流与MG的浓度在8.0×10^-9-5.0×10^-7mol.L^-1之间呈良好的线性关系,富集5m in检测限为4.0×10^-9mol.L^-1.并且将该新方法成功用于鱼中MG含量的测定.

In this paper,an electrochemical method for determination of malachite green （MG） is developed on the basis of enhancement effect of an anionic surfactant： sodium dodecyl benzene sulfonate （ SD- BS）. It is found that the oxidation peak current of MG at carbon paste electrode （CPE） significantly increases in the presence of low concentration of SDBS in pH 6.5 phosphate buffer, suggesting that SDBS shows obvious enhancement effect for the determination of MG. The experimental parameters, such as supporting electrolyte, surfactant type, concentration of SDBS and accumulation time, are optimized, and then a sensitive and convenient electrochemical method is proposed for the determination of MG. The oxidation peak current is proportional to the concentration of MG over the range from 8.0 × 10 ^-9 to 5.0 × 10 ^-7mol · L^-1 ,and the detection limit is 4.0 × 10^-9 mol · L^-1 after 5 min of accumulation. Finally, this new method is successfully employed to detect MG in fish samples.