Electrophoresis and electrochromatography

Most of the criteria and features outlined above for liquid chromatography media also apply to the development of selectors for electrodriven separations such as electrophoresis and electrochromatography. 

For reviews of applications of capillary electrophoresis and electrochromatography, see D. R. Baker. CapiUan- Electrophoresis An huroiluction. New York Wiley. 1995 Handbook of Capillary Electrophoresis, 2nd ed.. J. P. Landers, Ed. Boca Raton. fTL CRC Press, 1997 R. Weinberger, Practical Capillary Electrophoresis. New York Academic Press, 2000 S. N. Krylov and N. J. Dovichi, Anal. Chem., 2000, 72, 111R S. Hu and N. J. Dovichi. Anal. Chem., 2002, 74, 2833. 

Lister, A.S., Dorsey, J.G., and Burton, D.E., Current measurement of nonaqueous solvents Applications to capillary electrophoresis and electrochromatography,... 

Breadmore, M.C. (2007) Recent advances in enhancing the sensitivity of electrophoresis and electrochromatography in capillaries and microchips. Electrophoresis, 28 (1-2), 254-281. 

Zhang, M., Melonk, H. A., Chenanlt, K., and El Rassi, Z., Determination of cellular carbohydrates in peanut fungal pathogens and Baker s yeast by capillary electrophoresis and electrochromatography, J. Agric. Food Chem., 49, 5265, 2001. 

W. Wall and Z. El Rassi, Electrically driven microseparation methods for pesticides and metabolites. Part VII Capillary electrophoresis and electrochromatography of underivatized phenol pesticidic metabolites. Preconcentration and laser-induced fluorescence detection of dilute samples, J. Sep. ScL, 25, 1231-1244, 2002. 

Later, the same group developed what they call a hybrid microdevice as an alternative to quartz microchips. This device consisted of a short, fiised-sihca capillary column containing a 2.8-cm long polymer gel prepared from acrylamide, 2-acrylamido-2-methyl-l-propanesulfonic acid (AMPS), and allyl- -cyclodextrin as crosslinker. This capillary was set in a groove on a polyvinyl chloride support plate that included sample reservoirs, electrodes, and a sht for on-tube UV-detection. In addition, a ball lens was mounted beneath the detection sht to focus the UV beam. Gel electrophoresis and electrochromatography were then performed in this system. For example, several alkyl phenones were separated in the electrochromatographic mode in less than 200 s. The suggested separation mechanism was related to interactions between the hydrophobie cavity of the P-eyelodextrin and the analytes. However, no direet evidence for this meehanism was presented. 

Vegvaii, A. and Hjerten, S., A hybrid microdevice for electrophoresis and electrochromatography using UV detection. Electrophoresis, 23, 3479, 2002. 

Since electrophoresis can differentiate charged particles with great selectivity on the basis of their electrophoretic mobility, it has found extensive application in separation systems used in the biomedical industry, such as capillary electrophoresis [2], gel electrophoresis, and electrochromatography [3]. With the rapid development of modem microfluidic technology, electrophoresis has been successfully applied in the manipulation of microparticles and biological cells, by techniques such as isoelectric focusing [4] and electrokinetic dispensing [5]. 

Z. El Rassi (ed.) Paper Symposium Capillary Electrophoresis and Electrochromatography Reviews. Electrophoresis 20 (1999) 2989-3328. 

In capillary electrophoresis and electrochromatography, separations occur in a buffer-filled capillary tube under the influence of an electric field as seen in the schematic of Figure 30-1. Separations in field-flow frac-tioitation, on the other hand, occur in a thin ribbon-like flow channel under the influence of a sedimentation, electrical, or thermal field applied perpendicular to the flow direction. 

Hou, C., Herr, A.E. Clinically relevant advances in on-chip aflhnity-based electrophoresis and electrochromatography. Electrophoresis 2008 29 3306-3319. 

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