Isoelectric focusing in polyacrylamide gel

Isoelectric focusing in polyacrylamide gel today appears to be nearly the most popular version of this technique [142-145]. The essential components for the gel preparation are identical with those used with conventional polyacrylamide gel electrophoresis (see pg. 428). The only difference is that carrier ampholytes (2% w/w of the total gel volume) are incorporated into the gel solution before polymerization. The protein sample (free of salts) can be mixed with the sample gel solution or it can be loaded in the conventional way in a sucrose solution. In the latter case it is covered with a protective layer of ampholyte. 

Apparatuses for polyacrylamide gel isoelectric focusing are available from several leading manufacturers (LKB, ISCO, Hoeffer, Ortec, E.C.Med.Res.Apparatus, Buchler, Brinkman-Desaga). The advantages and disadvantages of slab gel and rod gel technique are practically the same as with conventional polyacrylamide gel electrophoresis. 

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Rodbard, D Chrambach, A, In Electrophoresis and Isoelectric Focusing in Polyacrylamide Gels Allen, RC Mauer, HR, eds. Walter E Gruyter New York, 1974 28. 

Ultrathin-layer isoelectric focusing in polyacrylamide gels on polyester films was performed as described (Radola, 1980). Polygalacturonase activity was detected by the print technique with a dyed substrate (Ostazin Brilliant Red-D-galacturonan DP 10) (Markovic et al., 1992) or by the print technique with colouress D-galacturonan DP 10 dyed additionally with ruthenium red (Sigma, Germany). 

The amino acids were analyzed from the press juices of the berries by an amino acid analyzer with ion-exchange columns as previously reported (17, 18). We described in detail the methods of disc electrophoresis and the isoelectrical focusing in polyacrylamid gels in another publication (8). 

Kumaratilake, L. M. Thompson, R. C. A. (1979). A standardized technique for the comparison of tapeworm soluble proteins by thin-layer isoelectric focusing in polyacrylamide gels, with particular reference to Echinococcus granulosus. Science Tools, 26 21-4. 

Dll. Drysdale, J. W., Righetti, P., and Bunn, H. F., The separation of human and animal hemoglobins by isoelectric focusing in polyacrylamide gel. Biochim. Bio-phys. Acta 229, 42-50 (1971). 

Drysdale JW. Isoelectric focusing in polyacrylamide gel. In Catsimpoolas, ed. Methods of protein separation, Vol 1. New York Plenum Publisliing Corp, 1975. 

Rodbard, D. Chrambach, A. In "Electrophoresis and Isoelectric Focusing in Polyacrylamide Gels" Allen, R.C. Maurer, H.R. 

The most powerful methods for the analysis of protein mixtures are electrophoretic. Isoelectric focusing In polyacrylamide gels Is capable of resolving proteins which differ in pi by 0.001 pH units ( ). As many as ten thousand components can be resolved by two dimensional techniques ( ). It is because of this power that analytical electrophoretic methods are used In numerous labs throughout the world. As a preparative methodology however, these techniques are... 

Multiple forms of the a-L-fucosidase from human liver have been revealed by isoelectric focusing in polyacrylamide gel and in thin layers of Sephadex. The aggregation of various forms of the enzyme was investigated. 

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