Oxidative and stepwise grafting of dopamine inner-sphere redox couple onto electrode material: electron transfer activation of dopamine.
Oxidative and stepwise grafting of dopamine inner-sphere redox couple onto electrode material: electron transfer activation of dopamine.
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DOI：
10.1021/ac402994u
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发表时间：
2013-11
影响因子：
7.4
通讯作者：
J. Ghilane;F. Hauquier;J. Lacroix
中科院分区：
文献类型：
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作者：
J. Ghilane;F. Hauquier;J. Lacroix
多巴胺，一种神经递质，固定到宏电极和微电极表面上已执行以下两个策略。第一种方法是基于酸性介质中氨基的电化学氧化的一步接枝。第二个是一个逐步的过程，开始与电化学接枝的重氮，导致连接的芳基层轴承的酸性头基，然后通过化学偶联导致固定多巴胺分子到电极表面上。电化学，红外（IR）光谱，和X-射线光电子能谱（XPS）分析的证据表明，这两种方法都适合于固定多巴胺到毫米和微米电极。修饰电极的电化学响应表明，连接的多巴胺层的电活性似乎不受间隔物，烷基或芳基层的性质，这表明通过隧道连接的多巴胺和电极之间的通信是可能的。更有趣的是，多巴胺修饰电极在溶液中表现出对多巴胺的电子转移活化。因此，多巴胺修饰电极不仅产生快速的电子转移，其ΔE（p）（30 mV）低于大多数预处理程序，而且ΔE（p）与更复杂的表面处理所观察到的一样小。
The immobilization of dopamine, a neurotransmitter, onto macroelectrode and microelectrode surfaces has been performed following two strategies. The first consists of a one-step grafting based on electrochemical oxidation of an amino group in acidic media. The second is a stepwise process starting with electrochemical grafting of diazonium, leading to the attachment of aryl layer bearing an acidic headgroup, followed by chemical coupling leading to immobilized dopamine molecules onto the electrode surface. Electrochemical, infrared (IR) spectroscopy, and X-ray photoelectron spectroscopy (XPS) analyses evidence that both methods are suitable for the immobilization of dopamine onto millimetric and micronic electrodes. The electrochemical responses of modified electrodes demonstrate that the electroactivity of the attached dopamine layer appears unaffected by the nature of the spacer, alkyl or aryl layers, suggesting that the communication, through tunneling, between the attached dopamine and the electrode is possible. More interestingly, the dopamine-modified electrode exhibits electron transfer activation toward dopamine in solution. As a result, not only does the dopamine modified electrode yield a fast electron transfer with lower ΔE(p) (30 mV) than the majority of pretreatment procedures but also the ΔE(p) is as small as that observed for more complex surface treatments.