Recent progress in capillary isotachophoresis

Abstract

This article is a continuation of previous reviews and summarizes the progress of analytical capillary isotachophoresis in the years 1997±1999. Papers reviewed include theoretical and methodological aspects as well as analytical applications. Included are also papers using isotachophoresis and/or isotachophoretic principles as part of multidimensional separation schemes.

Application of capillary isotachophoresis‐based multidimensional separations coupled with electrospray ionization‐tandem mass spectrometry for characterization of mouse brain mitochondrial proteome

“…While CITP has been widely used for analyte preconcentration prior to electrophoretic separation [35][36][37], the application of CITP to selectively enrich trace amounts of proteins/ peptides in complex mixtures presents an untapped strategy for maximizing proteome coverage. As demonstrated in our recent studies [38,39], such selective enhancement toward low abundance proteins can drastically reduce the range of relative protein abundances and greatly improve the sequence analysis of low-abundance proteins in complex proteomes such as human saliva proteome [39].…”

“…Even with reduced protein complexity in the subcellular proteome, the goal of achieving comprehensive proteome analysis is still challenged by the large variation of protein relative abundances. A capillary ITP (CITP)-based multidimensional separation platform, capable of providing selective analyte enrichment [35][36][37][38][39] and high resolving power toward complex protein/peptide mixtures, is therefore employed in this study for the analysis of synaptic mitochondria isolated from the brains of mice.…”

Isotachophoretic focusing and mass spectrometry detection as tools for improving the determination of aromatic sulfonates in capillary electrophoresis

“…Another approach is to preconcentrate the sample before the CE separation using conventional offline sample preconcentration procedures such as solidphase extraction (SPE) [2]. A third approach is to increase the sample loadability by on-line electrophoretic concentration [5][6][7][8][9][10][11][12][13][14][15]. The electrophoretic concentration methods increase the sample loadability without losing separation efficiency and can be performed using continuous (stacking procedures) or discontinuous (isotachophoretic procedures) electrolytes.…”

“…The electrophoretic concentration methods increase the sample loadability without losing separation efficiency and can be performed using continuous (stacking procedures) or discontinuous (isotachophoretic procedures) electrolytes. Although there are significant differences between these procedures, one common feature is that the analytes are concentrated at the boundary between the sample and the buffer/s over which there is a difference in the electrical field strength when a voltage is applied [5][6][7][8][9][10][11][12][13][14][15].…”

“…There are two different configurations for performing isotachophoresis-capillary zone electrophoresis (ITP-CZE): the single-capillary (one column) or dual-capillary (two columns coupled together) mode [7][8][9][10][11][12][13][14][15][16][17]. The main advantage of the latter configuration is that ITP can be used for sample cleanup and only the zones of interest are then analyzed by CZE.…”