碳糊电极的吸附/萃取行为及电化学测定美拉托宁

Adsorptive/Extractive Behavior of Melatonin at Carbon Paste Electrodes and Its Electrochemical Determination

报道了碳糊电极测定吲哚类神经化学物质美拉托宁 (MLTN)的灵敏电化学分析方法。该药物在电极上开路吸附 萃取预富集后 ,进行阳极溶出伏安测定 ,在 0 .70V附近显示了氧化溶出峰。MLTN在 2 .0× 10 -6～ 1.0× 10 -2 g L范围内峰电流与浓度呈线性关系 ,检测限可达 1.5× 10 -7g L。该法具有较强的抗干扰能力 ,在适当条件下VB6不干扰MLTN的测定。直接测定片剂中的MLTN含量 ,平均回收率为 98%。本文探讨了有机化合物在碳糊电极上的富集和溶出机理 ,发现碳糊电极对有机药物具有强烈的萃取和吸附作用 ,计时库仑法研究表明萃取在富集过程中起着主要作用。

The adsorptive/extractive behavior of melatonin at carbon paste electrodes was investigated. The results demonstrated that the adsorption and extraction played important roles during preconcentration,and the extraction was more important than adsorption. Malatonin was determined with differential pulse stripping voltammetry at carbon paste electrodes, and a sensitive anodic peak at 0.70V was observed( vs .Ag/AgCl). The response is linear at the range of 2.0×10 -6 ～1.0×10 -2 g/L with a detection limit of 1.5×10 -7 g/L. The method is sensitive, rapid and simple.