Institute of Materials Research & Engineering, Agency for Science, Technology and Research (A*STAR) 3 Research Link, Singapore.
Electrophoresis. 2010 Mar;31(6):1063-70. doi: 10.1002/elps.200900578.
An optimized capacitively coupled contactless conductivity detector for microchip electophoresis is presented. The detector consists of a pair of top-bottom excitation electrodes and a pair of pickup electrodes disposed onto a very thin plastic microfluidic chip. The detection cell formed by the electrodes is completely encased and shielded in a metal housing. These approaches allow for the enhancement of signal coupling and extraction from the detection cell that result in an improved signal-to-noise-ratio and detection sensitivity. The improved detector performance is illustrated by the electrophoretic separation of six cations (NH(4) (+), K(+), Ca(2+), Na(+), Mg(2+), Li(+)) with a detection limit of approximately 0.3 microM and the analysis of the anions (Br(-), Cl(-), NO(2) (-), NO(3) (-), SO(4) (2-), F(-)) with a detection limit of about 0.15 microM. These LODs are significantly improved compared with previous reports using the conventional top-top electrode geometry. The developed system was applied to the analysis of ions in bottled drinking water samples.
提出了一种用于微芯片电泳的优化电容耦合非接触式电导检测器。该检测器由一对顶-底激励电极和一对置于非常薄的塑料微流控芯片上的拾波电极组成。由电极形成的检测池完全被封装和屏蔽在金属外壳中。这些方法允许增强从检测池提取信号的能力，从而提高信号噪声比和检测灵敏度。电泳分离六种阳离子（NH4+，K+，Ca2+，Na+，Mg2+，Li+）和分析阴离子（Br-，Cl-，NO2-，NO3-，SO42-，F-）的实验结果说明了改进后的检测器性能，检测限分别约为 0.3 μM 和 0.15 μM。与使用传统的顶-顶电极几何形状的先前报告相比，这些 LOD 显著提高。开发的系统已应用于瓶装饮用水样品中离子的分析。
