Effects of mobile phase composition on the chromatographic and electrochemical behaviour of catecholamines and selected metabolites. Reversed-phase ion-paired high-performance liquid chromatography using multiple-electrode detection.
The effects of pH, ionic strength, organic modifier, heptanesulphonic acid and citric acid content of a high-performance liquid chromatography mobile phase on the chromatographic and electrochemical behaviour of norepinephrine, epinephrine, dopamine, 3,4-dihydroxybenzylamine, 3,4-dihydroxyphenylethylene glycol, 3,4-dihydroxyphenylalanine and 3,4-dihydroxyphenylacetic acid in a reversed-phase system have been systematically studied. Optimal mobile phase conditions have been derived allowing the separation and reductive-mode detection of these compounds, applicable to both alumina and ion-paired solvent extracts of plasma. It is demonstrated that mobile phase composition significantly affects the sensitivity of a triple-electrode electrochemical detection system, in reductive and oxidative modes, and that electrochemical pre-treatment of mobile phase is required to attain maximum detector sensitivity in the reductive mode.
Department of Biochemical Medicine, Ninewells Hospital, Dundee U.K.
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WA
Bartlett
D002395:Catecholamines / Q000097:blood*; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D004563:Electrochemistry; D004566:Electrodes; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents; D009994:Osmolar Concentration; D010084:Oxidation-Reduction
D002395:Catecholamines; D007202:Indicators and Reagents