Capillary zone electrophoresis separates look-alike peptides

Abstract

Chemists at Indiana University, Bloomington, have devised a separation technique for analyses of mixtures of closely related polypeptides [ J. Chromatogr. , 519 , 189 (1990)]. The technique may find use in assay, characterization, and sequencing of genetically engineered proteins. Developed by analytical chemistry professor Milos V. Novotny, the technique is a variation of capillary zone electrophoresis in which cyclodextrins are added to the aqueous buffer medium. In addition, Novotny has invented a series of intensely fluorescing derivativizing agents that allow detection of 10 to 18 attomoles (10 -18 mole) of peptides and other analyte types. Capillary zone electrophoresis typically uses capillary tubes about 1-meter long with a 50-μm internal diameter (C&EN, Mar. 7, 1988, page 27). Capillary outer walls are coated with polyimide to impart strength. Application of electric fields from 15 to 30 kV between capillary ends causes migration of analyte and buffer ions through the liquid as well as migration ...