Measurement of 3-methoxy-4-hydroxyphenylglycol in human plasma with high-performance liquid chromatography using electrochemical detection.
A new method utilizing high-performance liquid chromatography with electrochemical detection for the determination of unconjugated 3-methoxy-4-hydroxyphenylglycol, a major metabolite of norepinephrine, in human plasma is described. A novel internal standard, 3-ethoxy-4-hydroxyphenylglycol, was used to correct for variations in extraction efficiency and detector sensitivity. Separation of sample components was achieved isocratically in 20 min per sample in a reversed-phase system. Column temperature had to be carefully regulated. The sensitivity of the assay is suitable for clinical studies, with a limit of detection of 2 pmol/ml. Intra- and interassay precision was good, with observed coefficients of variation of 7.5 and 8.8%, respectively. Accuracy was tested by comparing the results of the present HPLC method to those found with a specific gas chromatographic-mass spectrometric assay. A satisfactory correlation of 0.96 was obtained, with no significant bias between the two methods.
D002851:Chromatography, High Pressure Liquid; D003010:Clorgyline / Q000494:pharmacology; D004563:Electrochemistry; D008401:Gas Chromatography-Mass Spectrometry; D006018:Glycols / Q000097:blood*; D006801:Humans; D008734:Methoxyhydroxyphenylglycol / Q000031:analogs & derivatives / Q000097:blood* / Q000592:standards; D012015:Reference Standards
D006018:Glycols; D008734:Methoxyhydroxyphenylglycol; C039016:3-ethoxy-4-hydroxyphenylglycol; D003010:Clorgyline