Modeling of formation and prevention of a pure water zone in capillary isoelectric focusing with narrow pH range carrier ampholytes

© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim..

This paper comprises a continuation of computer simulation studies dealing with carrier ampholyte based CIEF in presence of narrow pH gradients. With this technique, amphoteric sample components with pI values outside the pH gradient are migrating isotachophoretically toward the cathode or anode whereas components with pI values within the gradient become focused. In order to understand the processes occurring in presence of the electric field, the behavior of both carrier ampholytes and amphoteric sample components is investigated by computer modeling. Characteristics of two pH unit gradients with end components having pI values at or around 7.00 and conditions that lead to the formation of a water zone at neutrality were investigated. Data obtained reveal that a zone of water is formed in focusing with carrier ampholytes when the applied pH range does not cover the neutral region, ends at pH 7.00 or begins at pH 7.00. The presence of additional amphoteric components that cover the neutrality region prevent water zone formation under current flow. This situation is met in experiments with narrow pH gradients that end or begin around neutrality. Simulation data reveal that no water zone evolves when atmospheric carbon dioxide dissolved in the catholyte causes the migration of carbonic acid (in the form of carbonate and/or hydrogen carbonate ions) from the catholyte through the focusing structure. An electrolyte change in the electrode solution does not have an impact on the focusing part but does change the isotachophoretic pattern migrating behind the leading ion.

Medienart:

E-Artikel

Erscheinungsjahr:

2017

Erschienen:

2017

Enthalten in:

Zur Gesamtaufnahme - volume:38

Enthalten in:

Electrophoresis - 38(2017), 5 vom: 10. März, Seite 677-688

Sprache:

Englisch

Beteiligte Personen:

Takácsi-Nagy, Anna [VerfasserIn]
Kilár, Ferenc [VerfasserIn]
Thormann, Wolfgang [VerfasserIn]

Links:

Volltext

Themen:

059QF0KO0R
463-79-6
Ampholyte Mixtures
Carbonic Acid
Carbonic acid
Carrier ampholytes
Isoelectric focusing
Journal Article
Narrow pH gradient
Research Support, Non-U.S. Gov't
Simulation
Water
Water zone

Anmerkungen:

Date Completed 28.09.2017

Date Revised 06.11.2017

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1002/elps.201600314

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM264966155