Low-potential amperometric detection of dopamine based on MnO2 nanowires/chitosan modified gold electrode
Low-potential amperometric detection of dopamine based on MnO2 nanowires/chitosan modified gold electrode
复制标题
基于MnO2纳米线/壳聚糖修饰金电极的多巴胺低电位电流检测
DOI：
10.1016/j.electacta.2012.11.071
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发表时间：
2013-02-01
影响因子：
6.6
通讯作者：
Choi, Martin M. F.
中科院分区：
文献类型：
--
作者：
Huang, Ying;Cheng, Changming;Choi, Martin M. F.
本研究成功制备了二氧化锰（MnO 2）纳米线/壳聚糖修饰金（Au）电极，并在极低工作电位（0.00Vvs.SCE）下对多巴胺（DA）进行了安培测定。采用循环伏安法和电化学阻抗谱对修饰Au电极的电化学性能进行了表征。该检测方案包括两个主要反应：MnO 2纳米线将DA化学氧化为邻多巴胺醌，然后在低工作电位（0.00V vs. SCE）下将邻多巴胺醌电还原为DA，产生明显的还原响应电流。修饰的Au电极在0.10 μ M至1.10 mM的宽浓度范围内对DA显示出良好的安培响应。MnO 2纳米线/壳聚糖修饰的Au电极的制备简单，重现性好（RSD = 3.8%，n = 5）。该方法具有工作电位低（0.00Vvs.SCE）、储存期长（1个月后为初始响应值的90%）、重复性好（RSD = 2.2%，n = 5）等特点。最后将其应用于真实的样品中DA的直接测定，准确度为99%，回收率为99.7-103%，表明该方法在DA的常规分析中具有良好的应用前景。(C)2012爱思唯尔有限公司保留所有权利。
In this research, a manganese dioxide (MnO2) nanowires/chitosan-modified gold (Au) electrode was successfully fabricated for amperometric determination of dopamine (DA) at a very low working potential (0.00V vs. SCE). The electrochemical properties of the modified Au electrode were characterized by cyclic voltammetry and electrochemical impedance spectroscopy. The detection scheme was proposed to involve two major reactions: the chemical oxidation of DA to o-dopaminoquinone by MnO2 nanowires, and then the electro-reduction of o-dopaminoquinone to DA at a low working potential (0.00V vs. SCE), resulting in a distinct reduction response current. The modified Au electrode displays good amperometric response to DA in a wide concentration range 0.10 mu M to 1.10 mM. The fabrication of MnO2 nanowires/chitosan-modified Au electrode is simple and highly reproducible (RSD = 3.8%, n = 5). It exhibits excellent analytical performance in terms of low working potential (0.00V vs. SCE), long shelf-life (90% of its initial response after 1-month storage) and high repeatability (RSD = 2.2%, n = 5). Finally, it was applied to determine DA in real samples directly with high accuracy (99%) and good recovery (99.7-103%), confirming its promising application in routine DA analysis. (C) 2012 Elsevier Ltd. All rights reserved.