Gels, isoelectric focusing

Moio, L., Chianese, L., Rivemale, M., and Addeo, F. (1992). Fast detection of bovine milk in Roquefort cheese with PhastSystem by gel isoelectric focusing and immunoblotting. Lait 72, 87-93. 

W4. Wamick, G. R., Mayfield, C., Albers, J. J., and Hazzard, W. R., Gel isoelectric focusing method for specific diagnosis of familial hyperlipoproteinemia type 3. Clin Chem. 25, 279-284 (1979). 

T7. Thomas, J. A., and Beidler, D., A thin-gel isoelectric focusing method for quantitation of protein S-thiolation. Anal. Biochem. 157, 32—38 (1986). 

CIEF is the replication in the capillary of slab gel isoelectric focusing, a widely used separation mode, particularly suitable for protein separation. In isoelectric focusing, substances are separated by applying an electric field in a buffer system forming a pH gradient Analytes focus where the buffer local pH equals their isoelectric points. 

A4. Allen, R. C., Applications of polyacrylamide gel electrophoresis and polyacrylamide gel isoelectric focusing in clinical chemistry. /. Chromatogr. Biomed. Appl. 146, 1-32 (1978). 

H4. Harada, S., Agarwal, D. P., and Goedde, H. W., Application of gel isoelectric focusing and electrophoresis in the study of alcohol dehydrogenase and acetaldehyde dehydrogenase isoenzymes of human tissue and fibroblasts. In Electrophoresis 78 (N. Catsimpoolas, ed.), pp. 275-282. Elsevier, Amsterdam, 1979. 

L3. Latner, A. L., and Ernes, A. V., Further findings related to gel isoelectric focusing followed by electrophoresis. In Progress in Isoelectric Focusing and Isotachophoresis (P. G. Righetti, ed.), pp. 223-233. North-Holland Publ., Amsterdam, 1975. 

W9. Wright, G. L., Farrell, K. B., and Roberts, D. B., An evaluation of gradient acrylamide gel electrophoresis and acrylamide gel isoelectric focusing for the primary separation of complex mixtures of proteins Comparison of one- and two-dimensional analytical procedures. Biochim. Biophys. Acta 295, 396-411 (1973). 

Figure 2 illustrates the fractionation of a complex sample, an extract from Bermuda grass, which is a cannon allergen. Because of the heterogeneity of the sample, a broad range Ampholine was used, pH 3.5 - 10. The results of the fractionation were assessed by analytical polyacrylamide gel isoelectric focusing. Shown are the patterns of the original mixture and of the ten RIEF fractions. As can be... 

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. 

Although CE instruments are not well designed for CIEF, many variants can be separated better by this technique. In addition to the common variants, G Philadelphia, A2, and Bart s can all be separated by CIEF [46-48]. The separation by CIEF compares well with gel isoelectric focusing and with HPLC. The variants have also been analyzed by both CE and CIEF equipped with special absorption imaging detectors. These types of detection devices eliminate the extra steps needed to move the peaks, after the focusing step, to the detector and can simultaneously detect several capillaries with better precision and faster results than CE instruments. HB A2, which is increased in P-thal, is better quantified by CE compared with AG electrophoresis [44]. Hemoglobin analysis by CE has been reviewed recently [49-51]. 

Polyacrylamide gel isoelectric focusing of MDPF-labeled peptides has also been demonstrated (Stein, 1977). After the fluorogenic reaction the sample is desalted either with a molecular seiving column, such as Sephadex G-10, or by taking it to dryness and then dissolving the relatively hydro-phobic peptide fluorophor in an organic solvent. 

P. Dou and Z. Liu, At-line coupling of magnetic-nanoparticle-based extraction with gel isoelectric focusing for protein analysis. Anal. Bio-anal. Chem., 2011, 399(10), 3423-3429. 

Cellobiose or cellulose were necessary to induce the production of fS-D-glucosidase activity by Sporotrichum pulverulentum. Purification via preparative slab gel isoelectric focusing and affinity chromatography on a phenyl derivative of agarose gave five active fractions (p/ s 4.5—5.2, mol. wts. 1.65—1.82 X 10 by sodium dodecyl sulphate-polyacrylamide gel electrophoresis). 

Glucoamylase from an Endomycopsis species has been purified to homogeneity on disc electrophoresis in polyacrylamide gel, isoelectric focusing, and ultra-... 

Polyacrylamide Gel Isoelectric Focusing Two well-established techniques that use polyacrylamide are the gel cyhnder and the thin layer. Here we discuss only the gel cylinder technique because it is simpler and easier to understand. Figure 13.15... 

FIGURE 13.15 Disk electrophoresis apparatus for gel isoelectric focusing. Q> sample. 

Preliminary results using a new, flat-bed, gel isoelectric focusing method to study the heterogeneity of neuraminidases have been reported. The method has high resolution and the capacity to analyse many samples in a single experiment. The isoelectric points recorded were in good agreement with those obtained by other methods. 

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