Chloride present in biological samples as a tool for enhancement of sensitivity in capillary zone electrophoretic analysis of anionic trace analytes
- 30 January 2003
- journal article
- research article
- Published by Wiley in Electrophoresis
- Vol. 24 (3) , 505-517
- https://doi.org/10.1002/elps.200390059
Abstract
Effects originating from the variability of the sample matrix can be efficiently eliminated when the separation conditions are selected so that compounds of like charge with high concentration referred to as macrocomponents are embodied into the system of transient isotachophoresis. For stacking and separation of anionic trace analytes in biological samples, the presence of chloride is shown to be important to balance out effects of other macrocomponents that act against isotachophoretic stacking. Having acetoacetate, malate, citrate, and some drug metabolites in untreated human serum samples, the stacking mechanism of these compounds in an electrolyte system comprising 5 mM mandelic acid and ε-aminocaproic acid, pH 3.8, is explained. Analytes are monitored by indirect UV-absorption detection. Attention is paid to the minimum chloride concentration required with respect to the concentration ratio of phosphate (stacker) and lactate (destacker) present in the sample so as to ensure both stacking and separation of trace analytes. Insight into the separation process is given both with computer simulations and experiments. For selected analytes, the effect of chloride concentration on quantitative evaluation, sensitivity and limit of detection is demonstrated as well. Moreover, the applicability of the mobility window between phosphate and lactate for an additional group of metabolites is sketched.Keywords
This publication has 15 references indexed in Scilit:
- Quantitation of trace analytes in capillary zone electrophoresis with UV-absorbance detection: A critical study of approaches based on peak heightElectrophoresis, 2002
- Sample self-stacking in capillary zone electrophoresis: Behavior of samples containing multiple major coionic components*Electrophoresis, 2000
- Capillary zone electrophoresis of organic acids in serum of critically ill childrenJournal of Chromatography A, 1995
- Sample self‐stacking and sample stacking in zone electrophoresis with major sample components of like charge: General model and scheme of possible modesElectrophoresis, 1995
- Comparative use of three electrokinetic capillary methods for the determination of drugs in body fluidsJournal of Chromatography A, 1993
- Sample self-stacking in zone electrophoresisJournal of Chromatography A, 1992
- Computer-aided simulation of electromigrationJournal of Chromatography A, 1991
- Determination of pyruvate, acetoacetate, lactate, and 3-hydroxybutyrate in plasma of patients with diabetes mellitus by capillary isotachophoresisJournal of Microcolumn Separations, 1990
- Isotachophoresis with two leading ions and migration behaviour in capillary zone electrophoresisJournal of Chromatography A, 1990
- Organic Acids in ManPublished by Springer Nature ,1982