Simultaneous analysis of dopamine and homovanillic acid by high-performance liquid chromatography with wall-jet/thin-layer electrochemical detection
Simultaneous analysis of dopamine and homovanillic acid by high-performance liquid chromatography with wall-jet/thin-layer electrochemical detection
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采用壁射流/薄层电化学检测的高效液相色谱同时分析多巴胺和高香草酸
DOI：
10.1039/c3an01437a
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发表时间：
2013-01-01
期刊：
影响因子：
4.2
通讯作者：
Yao, Shouzhuo
中科院分区：
文献类型：
--
作者：
Zhou, Yaping;Yan, Hongling;Yao, Shouzhuo
采用壁式喷射/薄层安培电化学检测(ECD)与高效液相色谱(HPLC)联用的方法，在玻碳电极上同时测定了多巴胺(DA)和高香草酸(HVA)。与传统的薄层模式和壁面喷射模式相比，所提出的壁射流/薄层ECD具有更好地捕获工作电极上的电活性DA和HVA的优点，从而增强了对工作电极表面的响应，并更方便地对工作电极表面进行清洗/刷新。在优化条件下，DA和HVA在0.01~100 mm范围内线性关系良好，检出限分别为1.1 nM和0.7 nM，均低于UV-Vis检测器和市售电化学检测器。用人尿进行了测定，结果令人满意。本文还讨论了本系统的响应-信号、信号-背景和噪声水平的平衡。此外，通过恒电位体电解、电喷雾电离-质谱法、荧光分光光度法和循环伏安法的研究，提出了HVA的去甲基化电氧化机理。
Wall-jet/thin-layer amperometric electrochemical detection (ECD) coupled with high-performance liquid chromatography (HPLC) was used here for the simultaneous analysis of dopamine (DA) and homovanillic acid (HVA) at a glassy carbon electrode. Compared with the conventional thin-layer mode and wall-jet mode, the presented wall-jet/thin-layer ECD has the advantages of enhanced capture of electroactive DA and HVA on the working electrode to give enhanced responses and more convenient washing/refreshment of the working electrode surface. Under optimized conditions, the HPLC-ECD calibration curves show good linearity from 0.01 to 100 mM for DA and HVA, and the limits of detection (LODs) obtained were 1.1 nM for DA and 0.7 nM for HVA which are lower than those obtained with an UV-vis detector and a commercial electrochemical detector. The method was tested on human urine with satisfactory results. The balance of response-signal, signal-background and noise level for our HPLC-ECD system is also discussed. In addition, a demethylation electrooxidation mechanism for HVA is suggested through potentiostatic bulk electrolysis, electrospray ionization-mass spectrometry, fluorescent spectrophotometry and cyclic voltammetry studies.