Electrochemical detection of dopamine using arrays of liquid-liquid micro-interfaces created within micromachined silicon membranes
Electrochemical detection of dopamine using arrays of liquid-liquid micro-interfaces created within micromachined silicon membranes
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DOI：
10.1016/j.aca.2008.01.077
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发表时间：
2008-03-24
影响因子：
6.2
通讯作者：
Arrigan, Damien W. M.
中科院分区：
文献类型：
--
作者：
Berduque, Alfonso;Zazpe, Raul;Arrigan, Damien W. M.
采用差分脉冲伏安法（DPV）和方波伏安法（SWV）在两种不混溶电解质溶液（mu ITIES）之间的微界面阵列上检测质子化多巴胺。通过光刻和蚀刻工艺制备了微孔硅膜（由8个孔组成，半径26.6 μ m，孔孔间距500 μ m，呈六边形布局）。用疏水内壁制备膜孔，使有机相填充孔，并在膜的水侧形成液体界面。这些被用来利用三维扩散到界面和界面稳定的好处。液-液界面提供了一种简单的方法，克服了固体电极上由于抗坏血酸共存而导致的多巴胺伏安检测的主要问题。通过使用二苯并-18-冠-6 （DB18C6）促进多巴胺在mu - ITIES阵列上的离子转移，实现了多巴胺对抗坏血酸的选择性。在这些条件下，过量抗坏血酸的存在不会干扰多巴胺的检测，检测到的最低浓度约为0.5 μ m。此外，使用微加工多孔膜克服了在常规（毫米尺寸）液-液界面观察到的电流信号饱和（峰值电流随多巴胺浓度非线性增加）的缺点。(C) 2008 Elsevier B.V.版权所有
The detection of protonated dopamine by differential pulse voltammetry (DPV) and square wave voltammetry (SWV) at arrays of micro-interfaces between two immiscible electrolyte solutions (mu ITIES) is presented. Microfabricated porous silicon membranes (consisting of eight pores, 26.6 mu m in radius and 500 mu m pore-pore separation, in a hexagonal layout) were prepared by photolithographic and etching procedures. The membrane pores were fabricated with hydrophobic internal walls so that the organic phase filled the pores and created the liquid interface at the aqueous side of the membrane. These were used for harnessing the benefits of three-dimensional diffusion to the interface and for interface stabilisation. The liquid-liquid interface provides a simple method to overcome the major problem in the voltammetric detection of dopamine at solid electrodes due to the co-existence of ascorbate at higher concentrations. Selectivity for dopamine over ascorbate was achieved by the use of dibenzo-18-crown-6 (DB18C6) for the facilitated ion transfer of dopamine across the mu ITIES array. Under these conditions, the presence of ascorbate in excess did not interfere in the detection of dopamine and the lowest concentration detectable was ca. 0.5 mu M. In addition, the drawback of current signal saturation (non-linear increase of the peak current with the concentration of dopamine) observed at conventional (millimetre-sized) liquid-liquid interfaces was overcome using the microfabricated porous membranes. (C) 2008 Elsevier B.V. All rights reserved.