Quasi-isoelectric buffers for protein analysis in a fast alternative to conventional capillary zone electrophoresis

Quasi-isoelectric buffers for protein analysis in a fast alternative to conventional capillary zone electrophoresis
Engineering Village 2
2006 Elsevier Inc.
Accession number: 06129766398

Title: Quasi-isoelectric buffers for protein analysis in a fast alternative to conventional capillary zone electrophoresis

Authors: Antonioli, Paolo; Mendieta, Martha E.; Sebastiano, Roberto; Citterio, Attilio; Peltre, Gabriel; Busnel, Jean-Marc; Descroix, Stephanie; Candiano, Giovanni; Righetti, Pier Giorgio

Author affiliation: University of Verona, Department of Industrial and Agricultural Biotechnologies, Verona 37134, Italy

Serial title: Journal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences

Abbreviated serial title: J. Chromatogr. B Anal. Technol. Biomed. Life Sci.

Volume: v 833

Issue: n 1

Monograph title: 2nd Congress on Proteomics and Genomics

Issue date: Mar 20 2006

Publication year: 2006

Pages: p 19-25

Language: English

ISSN: 1570-0232


Document type: Journal article (JA)

Publisher: Elsevier, Amsterdam, 1000 AE, Netherlands

Abstract: Two different approaches are here reported for obtaining ultra-narrow pI cuts from 2-pH unit wide carrier ampholyte ranges, as commercially available, for use as quasi-isoelectric buffers in capillary electrophoresis separations of proteins. One of them uses multicompartment electrolyzers endowed with isoelectric membranes (Immobiline technology); the other employs the Rotofor equipment. Although the first approach results in more precise pI cuts, the latter technique is much faster, easier to handle and permits the immediate collection of 20 fractions in a single run. This results in ultra-narrow, ca. 0.1-pH unit intervals, uniformly spaced apart along the original wider gradient utilized for the fractionation. It is here shown that such quasi-isoelectric buffers, especially those in the pH 8-9 interval, have the unique property of coating the silica wall, thus preventing interaction of the proteins with the silica surface, that would otherwise totally disrupt the separation. On the contrary, such a shielding is not obtained in control, non isoelectric buffers (such as phosphate), that give very poor separations in uncoated capillaries. It is hypothesized that such a unique shielding effect is due to the oligo-amino backbone of the carrier ampholytes, typically composed (in the Vesterberg's synthetic approach) of 4-6 nitrogens spaced apart by ethylene moieties. Although such oligoprotic buffers should bear, in the isoelectric state, just one positive and one negative charge, they might be transiently ionized upon contact with the silanols, thus inducing a cooperative binding to the silica wall. ? 2005 Elsevier B.V. All rights reserved.

Number of references: 31

Ei main heading: Proteins

Ei controlled terms: Electrophoresis - Capillary flow - Nitrogen - Silica - Ethylene

Uncontrolled terms: Ultra-narrow-pH ampholytes cuts - Fractionation techniques - Isoelectric buffer - Uncoated-capillary CZE

Ei classification codes: 804.1 Organic Compounds - 701.1 Electricity: Basic Concepts & Phenomena - 801.3 Colloid Chemistry - 801.4.1 Electrochemistry - 631.1 Fluid Flow, General - 804 Chemical Products Generally - 482.2 Minerals

Treatment: Theoretical (THR)

DOI: 10.1016/j.jchromb.2005.10.017

Database: Compendex

Compilation and indexing terms, ? 2006 Elsevier Inc. All rights reserved
Subscription required: http://www.engineeringvillage2.org
Comments: 0