Capillary electrochromatography instrumentation

Flush for several hours at normal flow rates with the mobile phase to be used for the separation. Further condition on the capillary electrochromatography instrument with a stepwise increase in the operating voltage until a stable and adequate electroosmotic flow is obtained. 

Capillary electrochromatography-mass spectrometry (CE-MS), 4 641 Capillary electrodes, 14 27 Capillary electrophoresis (CE), 4 602-603, 631-633 6 385 9 751-752 antibody based columns with, 6 402 chiral additives, 6 77-79 applications, 4 641 basic principles, 4 606-609 detectors, 4 634-635 for DNA analysis, 4 636-637 flow profiles generated, 4 608 instrumentation, 4 633 as microfluidic assay technique,... 

This overview concerns the new chromatographic method - capillary electrochromatography (CEC) - that is recently receiving remarkable attention. The principles of this method based on a combination of electroosmotic flow and analyte-stationary phase interactions, CEC instrumentation, capillary column technology, separation conditions, and examples of a variety of applications are discussed in detail. 

Keywords. Capillary electrochromatography, Theory, Electroosmotic flow, Separation, Instrumentation, Column technology, Stationary phase, Conditions, Applications... 

Capillary electrochromatography (CEC) is a rapidly emerging analytical separation technique, with several different instrumental formats and prepacked CEC capillary columns now available. P15-323 As an advanced nanoseparation technology, CEC represents an orthogonal hybrid of HPLC and HP-CZE. As a consequence, resolution can be achieved... 

Figure 8.14. Schematic diagram of a pneumatic system retrofitted to a capillary electrophoresis instrument for capillary electrochromatography with simultaneous pressurization of the column inlet and outlet reservoirs.

Packed colunms with sintered frits (section 8.4.2) are generally operated at an elevated pressure to minimize bubble formation by applying an equal pressure to the column inlet and outlet electrolyte solution reservoirs. Pressures less than 500 p.s.i. are adequate for this purpose. A suitable setup to adapt a capillary electrophoresis instrument for use in capillary electrochromatography with pressure-equalized column operation is shown in Figure 8.14 [262]. 

Capillary Electrochromatography-Electrospray Ionization-Mass Spectrometry An Integrated Electrokinetic Analytical Technique, Fig. 1 Schematic CEC-ESI-MS instrumental arrangement... 

Capillary electrochromatography has experienced rapid progress during the last decade, expanding from 17 publications in 1994 to 191 in 2007. This has also led to several books and reviews [93-104] and analytical instrumentation is readily commercially available [105]. The developments in CEC include research on optimum stationary phases (polymer or silica based, adsorbed or imprinted, etc.), mobile phases (aqueous electrolytes with/without admixture of organic solvents or pseudophases) and apparatus design (open-tubular, packed or monolithic capillaries) up to lab-on-a-chip devices for pTAS [107]. 

U. Dyell, Advances in colimm technology and instrumentation in capillary electrochromatography. J. Chromatogr. A, 2000, 892, 257-278. 

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