Why robust background electrolytes containing multivalent ionic species can fail in capillary zone electrophoresis

0162261 - UIACH-O 20010008 RIV NL eng J - Journal Article
Beckers, J. L. - Gebauer, Petr - Boček, Petr
Why robust background electrolytes containing multivalent ionic species can fail in capillary zone electrophoresis.
Journal of Chromatography A. Roč. 916, č. 1 (2001), s. 41-49. ISSN 0021-9673. E-ISSN 1873-3778
R&D Projects: GA AV ČR IAA4031703; GA AV ČR IAA4031103; GA ČR GA203/99/0044; GA ČR GA203/01/0401
Institutional research plan: CEZ:AV0Z4031919
Keywords : capillary zone electrophoresis * system peaks * organic acids
Subject RIV: CB - Analytical Chemistry, Separation
Impact factor: 2.793, year: 2001

In this paper it is demonstrated that system peaks are inducted by multivalent weak ionic species in background electrolytes. Their existence is derived from SystCharts and from peak shape diagrams and the theory is confirmed experimentally. If analytes are present in a sample, with mobilities approximately equal to the mobility of a system peak, they interact, resulting in a strong increase of electromigration dispersion. This leads to a strong peak broadening, peak deformation and a loss of resolution. Typical background electrolytes containing multivalent ionic species, e.g. phosphate and phthalate buffers, in literature ofte proposed to be robust electrolytes, are therefore not always universally applicable and can fail for the application of specific analytes. This paper brings a systematic study of the above phenomena and shows theoretical and experimental results for BGEs containing phosphoric acid and phthalic acid.
Permanent Link: http://hdl.handle.net/11104/0059580