Applications of Zone Electrophoresis

DETERMINATION OF PROTEIN NET CHARGE AND MOLECULAR WEIGHT USING PAGE1 

Bianalytical Chemistry, by Susan R. Mikkelsen and Eduardo Corton ISBN 0-471-54447-7 Copyright 2004 John Wiley Sons, Inc. 

Kd value of the unknown is used with this plot to obtain the molecular weight of the 

Note that this calibration curve exhibits a linear region up to molecular weights that result in very little migration in the polyacrylamide gels. Data obtained for very high molecular weight protein standards tend to lack precision, due to the difficulty 

TABLE 10.1. Ferguson Slopes and Molecular Weights of Protein Standards 

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V7. von Frijtag, C. A. J., and Reinhold, ]. G., Application of zone electrophoresis to analysis of serum proteins. Technique for horizontal strip method and evaluation of its precision and accuracy. Anal. Chem. 27, 1090 (1955). 

Isolated examples of the use of zone electrophoresis have long been on record, but not until 1952 were the potentialities of its application to problems of carbohydrate chemistry reafized generally. The development and wide application of zone electrophoresis in the amino acid-peptide-protein... 

The examples selected above illustrate some of the many possible applications of zone electrophoresis. 

Kent and coworkers briefly reported the detection, after application of zone electrophoresis in barbiturate and other buffers, of a number of neutral polysaccharides, although no details of mobilities were noted. In a borate buffer at pH 8.0, amylopectin was observed to migrate toward the cathode and to be stained red with iodine, whereas amylose is stained blue and remains stationary. 

These results emphasize the value of results obtained by the application of zone electrophoresis in the comparison of polysaccharides of supposedly similar chemical structure. 

The last set of experiments provides examples of the application of capillary electrophoresis. These experiments encompass a variety of different types of samples and include examples of capillary zone electrophoresis and micellar electrokinetic chromatography. 

Zone electrophoresis is influenced by adsorption and capillarity, as well as by electroosmosis. Therefore evaluation of mobility (and f) from this type of measurement is considerably more complex than from either microelectrophoresis or moving-boundary electrophoresis. Nevertheless, zone electrophoresis is an important technique that is widely used in biochemistry and clinical chemistry. One particularly important area of application is the field of immunoelectrophoresis, which is described briefly in Section 12.11. Additional information on zone electrophoresis may be obtained from Probstein (1994) and Hunter (1981) and the references given there. Variants of zone electrophoresis also exist see, for example, Gordon et al. (1988) for information on a variant known as capillary zone electrophoresis and Righetti (1983) for information on what is known as isoelectric focusing. 

Another difference between other types of electrophoresis and disc electrophoresis is that the molecules in a sample do not start to significandy separate until entering the separating gel. A discontinuous gel system may be used with almost any type of zone electrophoresis application. 

An interesting application of gel electrophoresis concerns associating systems. The analysis of boundary profiles in transport processes by analytical sedimentation and elution from gel filtration columns, has been developed to a high degree of sophistication, and is of great importance in the study of proteins. For zone transport phenomena studies have been less complete. 

One significant application of ADSEP electrophoresis is direct measurement of electrophoretic mobilities as demonstrated in the present work. Capillary zone electrophoresis (CZE) is normally used to measure the electrophoretic mobility of solutes in free solution. Several undesirable features of CZE are absent in the present version of ADSEP, namely ... 

Butterman, M Tietz, D Orban, L Chrambach, A, Ferguson Plots Based on Absolute Mobilities in Polyarcylamide Gel Electrophoresis Dependence of Linearity of Polymerization Conditions and Application on the Determination of Free Mobility, Electrophoresis 9, 293, 1988. Caglio, S Chiari, M Righetti, PG, Gel Polymerization in Detergents Conversion Efficiency of Methylene Blue vs. Persulfate Catalysis, as Investigated by Capillary Zone Electrophoresis, Electrophoresis 15, 209, 1994. 

Yuan, K. et al., Application of capillary zone electrophoresis in the separation and determination of the curcuminoids in urine, J. Pharm. Biomed. Anal, 38, 133, 2005. 

Stuppner, H. and Egger, R., Application of capillary zone electrophoresis to the analysis of betalains from Beta vulgaris, J. Chromatogr. A, 735, 409, 1996. 

For many applications, diode array detection has become routine. A photodiode array was used for simultaneous detection of 100 capillaries in zone electrophoresis and micellar electrokinetic chromatography (MEKC).1516 Deflection of a laser beam by acoustic waves was reported as a means to scan six capillary channels on a microchip.17 The design of a low-noise amperometric detector for capillary electrophoresis has been reported.18... 

Kasicka, V., Pruslk, Z., Sazelova, P., Jiracek, J. and Barth, T., Theory of the correlation between capillary and free-flow zone electrophoresis and its use for the conversion of analytical capillary separations to continuous free-flow preparative processes. Application to analysis and preparation of fragments of insulin, ]. Chromatogr. A, 796, 211, 1998. 

Nishi et al. [110] used dextran and dextrin as chiral selectors in capillary-zone electrophoresis. Polysaccharides such as dextrins, which are mixtures of linear a-(l,4)-linked D-glucose polymers, and dextrans, which are polymers of D-glucose units linked predominantly by a-(l,6) bonds, have been employed as chiral selectors in the capillary electrophoretic separation of enantiomers. Because these polymers are electrically neutral, the method is applicable to ionic compounds. The enantiomers of basic or cationic drugs such as primaquine were successfully separated under acidic conditions. The effects of molecular mass and polysaccharide concentration on enantioselectivity were investigated. 

Factors Affecting Ionic Migration. Effect of Temperature. pH and Ionic Strength. Electro-osmosis. Supporting Medium. Detection of Separated Components. Applications of Traditional Zone Electrophoresis. High-performance Capillary Electrophoresis. Capillary Electrochromatography. Applications of Capillary El ectrochromatography. ... 

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