Strategy for Increasing the Electrode Density of Microelectrode Arrays by Utilizing Bipolar Behavior of a Metallic Film
Strategy for Increasing the Electrode Density of Microelectrode Arrays by Utilizing Bipolar Behavior of a Metallic Film
复制标题
利用金属薄膜的双极性行为增加微电极阵列的电极密度的策略
DOI：
10.1021/ac404202p
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发表时间：
2014
影响因子：
7.4
通讯作者：
Amatore Christian
中科院分区：
文献类型：
--
作者：
Zhu Feng;Yan Jiawei;Pang Shiwei;Zhou Yongliang;Mao Bingwei;Oleinick Alex;er;Svir Irina;Amatore Christian
采用光刻技术设计并制作了不同中心距的凹进微电极阵列和平面凹进微电极阵列。通过对平面凹进膜电极和凹进膜电极电化学行为的比较，揭示了金属平面膜的双极现象。当顶面电极浮置时，可以发生氧化还原循环;也就是说，无偏置的顶面电极的双极行为可以局部地作为集电极执行，并扩大Ru（NH3）6Cl 3的浓度梯度，从而促进MEA配置中微盘电极的表观发生器/集电极电化学响应。通过利用双极行为，实现稳态电流所需的MEA的中心到中心的距离可以减小，而不会同时有利于微电极的扩散层的重叠，因此，可以增加MEA的电极密度。因此，金属膜的双极行为可以增加单个微盘的电流响应和微盘的电极密度，而不损失微电极的特性。通过在平面上制作一层金属薄膜，并使其浮置而不受电位控制，本工作中使用的凹陷MEA可以实现检测灵敏度提高1个数量级以上。
Recessed microelectrode arrays and plane-recessed microelectrode arrays (MEAs) with different center-to-center distances are designed and fabricated using lithographic technology. By comparing electrochemical behavior of plane-recessed MEAs with that of recessed MEAs, bipolar phenomenon of the metallic plane film is revealed. Redox cycling can occur when the top plane electrode was floating; that is, the bipolar behavior of the unbiased top plane electrode may perform locally as a collector and enlarge the concentration gradient of Ru(NH3)6Cl3and thus promote an apparent generator/collector electrochemical response of the microdisk electrode in the MEAs configuration. By utilizing the bipolar behavior, the center-to-center distance of MEAs required for achieving steady-state current could decrease without favoring at the same time the overlapping of diffusion layers of microelectrodes, and thus, the electrode density of MEAs can be increased. Therefore, the bipolar behavior of the metallic film can increase both the current response of an individual microdisk and the electrode density of microdisks without losing the characteristics of a microelectrode. By just fabricating a thin layer of metallic film on the plane and leaving it floating without potential control, recessed MEAs used in this work can achieve the increase of detection sensitivity by more than 1 order of magnitude.