Methods electrophoresis

Most sample components analyzed with electrophoretic techniques are invisible to the naked eye. Thus methods have been developed to visualize and quantify separated compounds. These techniques most commonly involve chemically fixing and then staining the compounds in the gel. Other detection techniques can sometimes yield more information, such as detection using antibodies to specific compounds, which gives positive identification of a sample component either by immunoelectrophoretic or blotting techniques, or enhanced detection by combining two different electrophoresis methods in two-dimensional electrophoretic techniques. 

Cs Horvath and W. R. Melander, Theory of chromatography , in Chromatography Fundamentals and Applications of Chromatographic and Electrophoresis Methods. Part A Fundamentals and Techniques, Helftmann E. (Ed.), Journal of Cliromatography Library, Vol. 22, Ch. 3, A28-A135 (1983). 

H. Engelhar dt, W. Beck and T. Schmitt, Capillary Electrophoresis Methods and Potentials, Vieweg, Wiesbaden, Germany (1996). 

Douglas et al. [98] have measured protein (serum albumin, ovalbumin, and hemoglobin) mobilities over a range of pH values using a free-flow electrophoresis apparatus and a particle electrophoresis apparatus. They found good agreement between the two measurements however, they also found some differences between their measurements and those reported in the older literature. They attributed the differences to the use of moving-boundary electrophoresis methods in the early experimental work and to differences in... 

Frazierm, R.A. et ah. Development of a capillary electrophoresis method for the simultaneous analysis of colours, preservatives and sweeteners in soft drinks, J. 

Molecular weight of the components of the enzymatic complex was determined using a Sephadex G —75 column after its calibration by dextrans with molecular weight equal to 10,000, 40,000 and 70,000 and rafinose with molecular weight of 504. Fractions were also analyzed by the disk —electrophoresis method in PAAG (7) using 7.5% polyacrilamide gel (pH 4.3). Activity of pectinesterase was determined by titrometric method [8]. The enzymatically released methanol analyzed by gas—liquid chromatography [9]. 

Frazier, R. A. (2001). Recent advances in capillary electrophoresis methods for food analysis. Electrophoresis 22,4197-4206. 

Engelhardt, H., Beck, W., Kohr, J., and Schmitt, T., Capillary electrophoresis methods and scope, Angewandte Chemie, 32, 629, 1993. 

H. Watzig, M. Degenhardt, and A. Kunkel, Strategies for capillary electrophoresis Method development and validation for pharmaceutical and biological applications, Electrophoresis, 19, 2695 (1998). 

Myers, R.M., Maniatis, T. and Lerman, L.S. (1987) Detection and localization of single base changes by denaturing gel electrophoresis. Methods in Enzymology 155, 501-527. 

Stothard, J.R., Frame, IA. and Miles, MA. (1997) Use of polymerase chain reaction-based single strand conformational polymorphism and denaturing gradient gel electrophoresis methods for detection of sequence variation of ribosomal DNA of Trypanosoma cruzi. International Journal for Parasitology 27, 339-343. 

Fan et al. [106] developed a high performance capillary electrophoresis method for the analysis of primaquine and its trifluoroacetyl derivative. The method is based on the mode of capillary-zone electrophoresis in the Bio-Rad HPE-100 capillary electrophoresis system effects of some factors in the electrophoretic conditions on the separation of primaquine and trifluoroacetyl primaquine were studied. Methyl ephedrine was used as the internal standard and the detection was carried out at 210 nm. A linear relationship was obtained between the ratio of peak area of sample and internal standard and corresponding concentration of sample. The relative standard deviations of migration time and the ratio of peak area of within-day and between-day for replicate injections were <0.6% and 5.0%, respectively. 

Bortocan and Bonato [112] presented a capillary electrophoresis method for the enantioselective analysis of primaquine and its metabolite carboxyprimaquine. The method is used for the simultaneous determination of the drug and its metabolite, in... 

P. Schmitt Kopplin, Capillary Electrophoresis. Methods and Protocols, Humana Press, Neuherberg (2008). 

Finally, work that may facilitate understanding the role of oq-acid glycoprotein variants in inter-individual variations in plasma protein binding, pharmacokinetic behavior, and drug action has been described. A capillary zone electrophoresis method that allows for the determination of 11 intact forms (i.e., isoforms, glycoforms) of oq-acid glycoprotein has been described [84],... 

The -potential of the metal-oxide particles was measured by means of the micro-electrophoresis method (11). 

G. Lunn (Ed.), Capillary Electrophoresis Methods for Pharmaceutical Analysis, Wiley-Interscience, New York, 2000. 

R.A. Frazier, E.L. Inns, N. Dossi, J.M. Ames and H.E. Nursten, Development of a capillary electrophoresis method for the simultaneous analysis of artifical sweeteners, preservatives and colours in soft drinks. J. Chromatogr.A, 876 (2000) 213-220. 

Tim Wehr is Staff Scientist at Bio-Rad Laboratories in Hercules, California. He has more than 20 years of experience in biomolecule separations, including development of HPLC and capillary electrophoresis methods and instrumentation for separation of proteins, peptides, amino acids, and nucleic acids. He has also worked on development and validation of LC-MS methods for small molecules and biopharmaceuticals. He holds a B.S. degree from Whitman College, Walla Walla, Washington, and earned his Ph.D. from Oregon State University in Corvallis. 

DNLM 1. Pharmaceutical Preparations—analysis—Laboratory Manuals. 2. Biopharmaceutics—methods—Laboratory Manuals. 3. Chromatography—methods—Laboratory Manuals. 4. Electrophoresis—methods—Laboratory Manuals. 5. Spectrum Analysis-methods—Laboratory Manuals. QV 25 A5338 2005] I. Wehr, Tim. II. Rodnguez-Dlaz, Roberto. III. Tuck, Stephen (Stephen F.)... 

Proteins can be separated using the 2D electrophoresis method. The first dimension is separation according to the pH of the proteins. The proteins are placed on a gel strip in a buffer solution. An electrical current is applied and the proteins separate and migrate to their isoelectric points (pl)-... 

Zhou, L., Thompson, R., Song, S., Elhson, D., Wyvratf J.M. A strategic approach to the development of capillary electrophoresis methods for pharmaceutical basic compounds nsing sulfated cyclodextrins. J. Pharm. Biomed. An. 2002, 27, 541-553. 

The origins, principles, methods, and modes of capillary electrophoresis (CE) are discussed. Massive application of electrophoresis methods started after Tiselius s moving boundary method that was optimized by the use of paper or a gel as a semiconducting medium. The applications of paper and gel electrophoresis were situated mostly in the biochemical environment for the analysis of proteins, amino... 

Table 12 gives an orientation help for CE separations sorted by pharmaceutical substances published in review articles. As this chapter focuses on the technical development of drug substances and products, only drug substances and drug formulations are covered. A useful compendium of CE applications in the pharmaceutical environment can be found in the book Capillary Electrophoresis Methods for Pharmaceutical Analysis written by G. Lunn. The book covers more than 700 active pharmaceutical ingredients and contains short method descriptions, sample preparation steps, and references. 

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