Osbourn Damon M, Lunte Craig E
Department of Chemistry, University of Kansas, 1251 Wescoe Hall Dr., Lawrence, Kansas 66045, USA.
Anal Chem. 2003 Jun 1;75(11):2710-4. doi: 10.1021/ac026354l.
The development of a cellulose acetate decoupler for on-column electrochemical detection in microchip capillary electrophoresis is presented. The capillary based laser-etched decoupler is translated to the planar format to isolate the detector circuit from the separation circuit. The decoupler is constructed by aligning a series of 20 30-microm holes through the coverplate of the microchip with the separation channel and casting a thin film of cellulose acetate within the holes. The decoupler shows excellent isolation of the detection circuit for separation currents up to 60 microA, with noise levels at or below 1 pA at a carbon fiber electrode. Detection limits of 25 nM were achieved for dopamine. This decoupler design combines excellent mechanical stability, effective shunting of high separation currents, and ease of manufacture.
本文介绍了一种用于微芯片毛细管电泳柱上电化学检测的醋酸纤维素去耦器的研制。基于毛细管的激光蚀刻去耦器被转换为平面形式，以将检测电路与分离电路隔离开来。通过将一系列20个30微米的孔穿过微芯片的盖板与分离通道对齐，并在孔内浇铸醋酸纤维素薄膜来构建去耦器。对于高达60微安的分离电流，该去耦器对检测电路显示出优异的隔离效果，在碳纤维电极处噪声水平为1皮安或更低。多巴胺的检测限达到25纳摩尔。这种去耦器设计兼具出色的机械稳定性、对高分离电流的有效分流以及易于制造的特点。
