Capillary electrochromatography analysis

Yan, C., et al.. Capillary electrochromatography Analysis of polycyclic aromatic hydrocarbons. Anal. Chem., 67, 2026, 1995. 

Zhao, R.R. and Johnson, B.P., Capillary electrochromatography analysis of sucralose and related carbohydrate compounds, J. Liq. Chromatogr. Rel. Techrwl., 23,1851, 2000. 

Capillary Electrochromatography Another approach to separating neutral species is capillary electrochromatography (CEC). In this technique the capillary tubing is packed with 1.5-3-pm silica particles coated with a bonded, nonpolar stationary phase. Neutral species separate based on their ability to partition between the stationary phase and the buffer solution (which, due to electroosmotic flow, is the mobile phase). Separations are similar to the analogous HPLC separation, but without the need for high-pressure pumps, furthermore, efficiency in CEC is better than in HPLC, with shorter analysis times. 

CE was recently used for anthocyanin analysis because of its excellent resolution. This technique has different modes capillary zone electrophoresis (CZE), capillary gel electrophoresis (CGE), micellar electrokinetic chromatography (MEKC), capillary electrochromatography (CEC), capillary isoelectric focusing (CIEE), and capillary isotachophoresis (CITP)."° CZE is the most popular method for anthocyanin... 

LC is currently used extensively in the photographic industry. One application is to quantify some of the components of photographic paper. As demands to reduce analysis time increase, an analytical method that can give improved productivity is required. One possible alternative to LC is capillary electrochromatography (CEC). In a recent paper, this analytical protocol was applied to separate some color photographic paper components <2002MI1>. 

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,... 

The hyphenation of CE and NMR combines a powerful separation technique with an information-rich detection method. Although compared with LC-NMR, CE-NMR is still in its infancy it has the potential to impact a variety of applications in pharmaceutical, food chemistry, forensics, environmental, and natural products analysis because of the high information content and low sample requirements of this method [82-84]. In addition to standard capillary electrophoresis separations, two CE variants have become increasingly important in CE-NMR, capillary electrochromatography and capillary isotachophoresis, both of which will be described later in this section. 

After a short introduction into the relevance of Impurity profiling for regulatory authorities, public health, and the pharmaceutical industry, an overview is presented based on the various modes of capillary electrophoresis that have been used in drug impurity analysis. The applications of capillary zone electrophoresis, non-aqueous capillary electrophoresis, micellar electrokinetic capillary chromatography, microemulsion electrokinetic capillary chromatography, capillary gel electrophoresis, and capillary electrochromatography are presented consecutively. 

Capillary electrochromatography (CEC) is a miniaturized separation technique that combines aspects of both interactive chromatography and capillary electrophoresis. In this chapter, the theory of CEC and the factors affecting separation such as the stationary phase and mobile phase parameters have been discussed. The chapter focuses on the types and preparation of columns for CEC and describes the progress made in the development of open-tubular, particle-packed, and monolithic columns. The detection techniques in CEC such as the traditional UV detection and improvements made in coupling with more sensitive detectors such as mass spectrometry are also described. The chapter provides a summary of some applications of CEC in the analysis of pharmaceuticals and biotechnology products. 

Hindocha, D., and Smith, N. W. (2002). The analysis of basic pharmaceutical compounds by capillary electrochromatography using continuous bed stationary phase. Chromatographia 55, 203-209. 

Johannesson, N., Wetterhall, M., Markides, K. E., and Bergquist, J. (2004). Monomer surface modifications for rapid peptide analysis by capillary electrophoresis and capillary electrochromatography coupled to electrospray ionization-mass spectrometry. Electrophoresis 25, 809-816. 

De Rossi, A., and Desiderio, C. (2005). Application of reversed phase short end-capillary electrochromatography to herbicides residues analysis. Chromatographia 61, 271—275. 

Dedicated applications of capillary zone electrophoresis (CZE) coupled to MS are discussed, particularly in the field of drug analysis. Development of other capillary-based electrodriven separation techniques such as non-aqueous capillary electrophoresis (NACE), micellar electrokinetic chromatography (MEKC), and capillary electrochromatography (CEC) hyphenated with MS are also treated. The successful coupling of these electromigration schemes with MS detection provides an efficient and sensitive analytical tool for the separation, quantitation, and identification of numerous pharmaceutical, biological, therapeutic, and environmental compounds. 

Taylor, M. R., Teale, P., Westwood, S. A., and Perrett, D. (1997). Analysis of corticosteroids in biofluids by capillary electrochromatography with gradient elution. Anal. Chem. 69, 2554-2558. 

Ding, J. M., and Vouros, P. (1997). Capillary electrochromatography and capillary electrochromatography-mass spectrometry for the analysis of DNA adduct mixtures. Anal. Chem. 69, 379—384. 

Cherkaoui, S., Cahours, X., and Veuthey, J. L. (2003). Analysis of selected withanolides in plant extract by capillary electrochromatography and microemulsion electrokinetic chromatography. Electrophoresis 24, 336—342. 

Wu, J. T., Huang, P. Q., Li, M. X., Qian, M. G., and Lubman, D. M. (1997). Open-tubular capillary electrochromatography with an on-line ion trap storage/reflectron time-of-flight mass detector for ultrafast peptide mixture analysis. Anal. Chem. 69, 320-326. 

Paterson, C. J., Boughtflower, R. J., Higton, D., and Palmer, E. (1997). An investigation into the application of capillary electrochromatography-mass spectrometry (CEC-MS) for the analysis and quantification of a potential drug candidate in extracted plasma. Chromatographia 46, 599-604. 

Finally, when RPC methods are used in preparative studies with peptides, the opportunity routinely exists for subsequent analysis of the recovered fractions by a variety of analytical methods including high-speed RP-HPLC, HP-IEX, HP-HILIC, or HP-IMAC, zonal or micellar electrokinetic high-performance capillary electrophoresis (HP-CZE and MECK-CZE), capillary electrochromatography (CEC), or capillary isotachophoresis. The combination of the RPC information, drawn from the In k versus i > plots, with the data derived from on-line spectroscopic detection thus readily provides a comprehensive opportunity to assess the purity of an isolated peptide, many of the physicochemical features of the interaction, as well as a means to optimize the resolution in the RPC separation. 

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