Determination of 3,4-dihydroxyphenylacetic acid and 5-hydroxyindoleacetic acid in human plasma by a simple and rapid high-performance liquid chromatography assay.
In order to study the pharmacodynamic effects of drugs on dopamine and serotonin metabolism, a reversed-phase HPLC assay coupled with electrochemical detection (ECD) for measuring plasma concentrations of 3,4-dihydroxyphenylacetic acid (DOPAC) and 5-hydroxyindoleacetic acid (5-HIAA) was developed. The system was operated isocratically using a mobile phase of aqueous 0.03 M KH2PO4 buffer containing 0.15 mM EDTA in methanol (8.75:1.25), with a final pH of 4.0. The flow rate was set at 1.5 mL/min, and potentials at +450 mV. Using a signal to noise ratio of > 3, the minimum detection limit assessed by direct on-column injection of a standard solution for DOPAC and 5-HIAA was < 1 pg. The assays were linear from basal concentrations (1-10 ng/mL) to 100 ng/mL. The intra- and interassay variations were < 10% and < 20%, respectively.
Yeung
P K
PK
Pharmacokinetics & Metabolism Laboratory, Dalhousie University, Halifax, NS, Canada.
Buckley
S J
SJ
Pedder
S C
SC
Dingemanse
J
J
D015102:3,4-Dihydroxyphenylacetic Acid / Q000097:blood*; D000328:Adult; D001549:Benzamides / Q000097:blood; D002851:Chromatography, High Pressure Liquid; D006801:Humans; D006897:Hydroxyindoleacetic Acid / Q000097:blood*; D020912:Moclobemide
D001549:Benzamides; D015102:3,4-Dihydroxyphenylacetic Acid; D006897:Hydroxyindoleacetic Acid; D020912:Moclobemide