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Base-induced transient isotachophoretic stacking of acidic drugs in capillary zone electrophoresis
journal contribution
posted on 2023-05-17, 12:05 authored by Joselito QuirinoOnline sample concentration of acidic drugs by transient isotachophoresis (t-ITP) with the injection of a base is described in capillary zone electrophoresis (CZE). A positively coated capillary was conditioned with background electrolyte (ammonium acetate at pH 6). A long plug of sample solution (S) prepared in ammonium acetate was then hydrodynamically injected followed by the base (tetrapropylammonium hydroxide). A negative voltage was applied and caused the hydroxide ions from the base to penetrate the S zone and created a pH junction that swept through the S zone. The analytes stack at the junction where the mechanism of focusing was transient ITP with the acetate and hydroxide ions as leading and terminating ions, respectively. The concentrated analytes separated in co-EOF CZE once the hydroxide was exhausted. The base stacking strategy was tested using hypolipidemic, nonsteroidal anti-inflammatory, and diuretic drugs, and afforded 19–37 improvements in peak height.
History
Publication title
Journal of Separation ScienceVolume
34Issue
9Pagination
1020-1026ISSN
1615-9306Department/School
School of Natural SciencesPublisher
Wiley - VCH Verlag GmbH & Co.Place of publication
GermanyRights statement
Copyright 2011 Wiley-VCH Verlag GmbHRepository Status
- Restricted