Determination of urinary norepinephrine and epinephrine by liquid chromatography with fluorescence detection and pre-column derivatization.
We assayed norepinephrine and epinephrine by utilizing solvent extraction, fluorescence derivatization, and "high-performance" liquid chromatography. A 100-microL aliquot of urine was extracted twice according to Smedes et al. (J Chromatogr 1982;231:25-39) and subsequently incubated with 1,2-diphenylethylenediamine. A 100-microL aliquot of the resulting mixture was injected into a reversed-phase column, and norepinephrine and epinephrine were detected fluorometrically. The within-day CV was 3.0-4.0% and the between-day CV 3.4-7.1% for normal and high concentrations of both analytes. At low concentrations (15-40 nmol/L) these CVs were 4.2-6.8% and 6.8-9.2%, respectively. The detection limit of the assay was less than 0.4 nmol/L for each analyte. We discuss the critical steps for extraction, derivatization, and chromatography. The present method combines the qualities of high precision, specificity, and sensitivity.
Moleman
P
P
Department of Psychiatry, Academic Hospital Rotterdam Dijkzigt, The Netherlands.
van Dijk
J
J
D002851:Chromatography, High Pressure Liquid; D004837:Epinephrine / Q000652:urine*; D006801:Humans; D009638:Norepinephrine / Q000652:urine*; D013050:Spectrometry, Fluorescence
D009638:Norepinephrine; D004837:Epinephrine