Zone selection, capillary isotachophoresis

Y. An, J. W. Cooper, B. M. Balgley, and C. S. Lee. Selective Enrichment and Ultrasensitive Identification of Trace Peptides in Proteome Analysis Using Transient Capillary Isotachophoresis/Zone Electrophoresis Coupled with Nano-ESI-MS. Electrophoresis, 27(2006) 3599-3608. 

An, Y., Cooper, W.J., Balgley, M.B., and Lee, C.S. Selective enrichment and ultrasensitive identification of trace peptides in proteome analysis using transient capillary isotachophoresis/zone electrophoresis coupled with nano-ESI-MS. Electrophoresis, 27, 3503, 2006. 

Several strategies have been described for the preconcentration of sample components present at low concentrations. These techniques include zone sharpening,28-29 on-line packed columns,30 and transient capillary isotachophoresis (cITP).31-32 Other standard laboratory techniques are often used, including solid-phase extraction, protein precipitation, ultrafiltration, etc. Two important points to keep in mind when selecting a concentration protocol are the sample requirements of the method and the potential selectivity on relative concentrations of sample components. The latter point applies to purity and concentration analysis. 

Triethanolamine can be determined in metalworking and cutting fluids by gas chromatography-mass selective detection of silylated derivatives, by isotachophoresis, by capillary zone electrophoresis with indirect ultraviolet detection, and by spectrophotometry (Kenyon et al, 1993 Fernando, 1995 Schubert et al, 1996 Sollenberg, 1997) and in cosmetics and pharmaceuticals by ion-exclusion chromatography and by reversed-phase high performance liquid chromatography (Fukui et al, 1992 Maurer etal, 1996). 

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