Abstract
A micellar electrokinetic capillary chromatographic method for
determining anionic catecholamine metabolites from patient urine samples
was established. The optimum electrolyte solution (pH 10.6) was made of
tetraborate and sodium dodecyl sulphate into water. Furthermore,
studies were focused to optimize solid-phase extraction clean-up steps
to concentrate patient urine samples for identification of
catecholamines with UV detection. The water-micelle distribution
coefficients (octanol–water partition coefficient, log Pow) for the analytes were determined by conductometric titration. High plate numbers (120 000–200 000/40 cm detection window) and small diffusion coefficients (2.00–3.50×10−6 cm−2 s−1)
resulted in high resolution and symmetry of the analyte zones. The
standard deviations of the migration times and the peak heights were
less than 3 and 7%, respectively. The octanol–water coefficients
increased in the order of decreased pKa1 value of
the analytes, why separation between structurally related vanillinic
mandelic acids could be obtained. Limits of detection and quantification
were around 0.05 and 0.1 μg/ml, respectively, except for dopamine. The
concentrations of the catecholamine metabolites in the studied patient
urines varied from 0.186 to 76.4 μg/ml. The results showed evidences of serious diseases among the patients.
Original language | English |
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Pages (from-to) | 289-297 |
Journal | Journal of Chromatography A |
Volume | 1032 |
Issue number | 1-2 |
DOIs | |
Publication status | Published - 2004 |
MoE publication type | A1 Journal article-refereed |
Keywords
- octanol-water partition coefficients
- capillary electrophoresis
- catecholamines