Conventional electrophoresis types

Further DNA analysis It is also possible to conduct further steps beyond conventional electrophoresis to allow more advanced analyses of the separated DNA bands. Of these steps, blotting is arguably the most versatile tool for further analysis. As outlined earlier, there are various types of blotting, but the most popular... 

In this section, instrumentation, general electrophoretic operations, technical and practical considerations, and types of conventional electrophoresis are discussed. 

In contrast to the cumbersome and time-consuming tasks of conventional electrophoresis, CE is well suited to automation. Samples are easily applied to the capillary, a variety of detector types can be used, and the resulting electrophore-tograms can be analyzed and manipulated in much the same manner as chromatograms. Commercial instruments resemble many HPLC instruments in terms of automated sample loading and data analysis. Traditional serum protein electrophoresis, for example, can be fully automated with CE. 

A preliminary validation study (unpublished data) demonstrated that subtyping of Gc by the method described by Budowle (31) markedly improved the rate of conclusive phenotype determinations for casework specimens. Two hundred and sixty-six known liquid blood specimens obtained from cases submitted to the FBI Laboratory were analyzed for Go by both ULPAGIF and conventional electrophoresis (3 ) The data revealed that 92.131 were conclusively typed by ULPAGIF compared with 63,236 by conventional electrophoresis. There were no... 

Hemoglobin variants have been typed by conventional electrophoresis on cellulose acetate or agarose and by lEF (1, 52, 66-70). Budowle and Eberhardt (5 ) recently developed an ULPAGIF method for typing the A, F, S, C and a number of rare variants, which is presently used for the analysis of bloodstained evidence submitted to the FBI Laboratory. The method employs pH 6.7-7.7 Pharmalytes in an ultrathin-layer gel with an inter-electrode wick distance of only 5.0 cm. The result is a rapid screening method for Hb that takes only 25-30 minutes-comparable to cellulose acetate. Further, the distances between the A-F, F-S and S-C were 4 oim, 7 mm and 12 mm, respectively, compared with 3 mm, 5.5 nim, and... 

Jayle, Herman-Boussier, and Moretti have shown that different types of human Hp in amounts large enough for analysis can be prepared by fractional ammonium sulfate precipitation combined with a rather conventional, preparative electrophoresis in an acetate buffer of pH 5.8. Schultze and Heide (S2) utilize a more complicated procedure, in which preparative electrophoresis (acetate buffer, pH 4.4) is likewise the final step. 

This type of detection has achieved much development in the last few years due to its simplicity. A specific revision on conductimetric (and potentiometric) detection in conventional and microchip capillary electrophoresis can be found in Ref. [57]. It is considered a universal detection method, because the conductivity of the sample plug is compared with that of the solution and no electroactivity of the analytes is required. Two electrodes are either kept in galvanic contact with the electrolyte (contact conductivity) or are external and coupled capaci-tively to the electrolyte (contactless mode). An alternating current potential is applied across the electrodes and the current due to the conductivity of the bulk solution is measured. As the signal depends on the difference in conductivity between solution and analyte zones, the choice of the electrolyte is crucial. It is necessary that it presents different conductivity without affecting sensitivity. 

The chiral recognition mechanisms in NLC and NCE devices are similar to conventional liquid chromatography and capillary electrophoresis with chiral mobile phase additives. It is important to note here that, to date, no chiral stationary phase has been developed in microfluidic devices. As discussed above polysaccharides, cyclodextrins, macrocyclic glycopeptide antibiotics, proteins, crown ethers, ligand exchangers, and Pirkle s type molecules are the most commonly used chiral selectors. These compounds... 

Roudiere L, Boularan AM, Bonardet A, VaUat C, Ciistol JP, Dupuy AM. Evaluation of a capillary zone electrophoresis system versus a conventional agarose gel system for routine serum protein separation and monoclonal component typing. Clin Lab 2006 52 19-27. 

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