Osbourn D M, Weiss D J, Lunte C E
Department of Chemistry, University of Kansas, Lawrence 66045, USA.
Electrophoresis. 2000 Aug;21(14):2768-79. doi: 10.1002/1522-2683(20000801)21:14<2768::AID-ELPS2768>3.0.CO;2-P.
The limits of detection (LOD) for capillary electrophoresis (CE) are constrained by the dimensions of the capillary. For example, the small volume of the capillary limits the total volume of sample that can be injected into the capillary. In addition, the reduced pathlength hinders common optical detection methods such as UV detection. Many different techniques have been developed to improve the LOD for CE. In general these techniques are designed to compress analyte bands within the capillary, thereby increasing the volume of sample that can be injected without loss of CE efficiency. This on-line sample preconcentration, generally referred to as stacking, is based on either the manipulation of differences in the electrophoretic mobility of analytes at the boundary of two buffers with differing resistivities or the partitioning of analytes into a stationary or pseudostationary phase. This article will discuss a number of different techniques, including field-amplified sample stacking, large-volume sample stacking, pH-mediated sample stacking, on-column isotachophoresis, chromatographic preconcentration, sample stacking for micellar electrokinetic chromatography, and sweeping.
毛细管电泳（CE）的检测限（LOD）受毛细管尺寸的限制。例如，毛细管的小体积限制了可注入毛细管的样品总体积。此外，较短的光程阻碍了诸如紫外检测等常见的光学检测方法。已经开发了许多不同的技术来提高CE的LOD。一般来说，这些技术旨在压缩毛细管内的分析物谱带，从而增加可注入的样品体积而不损失CE效率。这种在线样品预浓缩，通常称为堆积，基于两种具有不同电阻率的缓冲液边界处分析物电泳迁移率差异的操纵或分析物在固定相或假固定相中的分配。本文将讨论多种不同的技术，包括场放大样品堆积、大体积样品堆积、pH介导的样品堆积、柱上等速电泳、色谱预浓缩、胶束电动色谱的样品堆积以及扫集。
