title: Simultaneous quantitation of ephedrines in urine by gas chromatography-nitrogen-phosphorus detection for doping control purposes.
abstract: A gas chromatographic method for the simultaneous quantitation of ephedrine, pseudoephedrine, norephedrine (phenylpropanolamine), norpseudoephedrine (cathine) and methylephedrine in urine is described. The method consists of a liquid-liquid extraction with tert.-butyl methyl ether at pH 14. The extracts are analysed on a GC system equipped with an Rtx-5 Amine column and a nitrogen-phosphorus detector. Method validation shows excellent separation, linearity, specificity, accuracy, precision, intra-laboratory repeatability and reproducibility, making the method especially suitable for quantitation of ephedrines in urine samples for doping control purposes. A statistical analysis on the abuse of the different ephedrines in urine from athletes controlled in the Flemish doping control laboratory during the period 1993-2000 is included.
authors.affiliation: Ghent University, Department of Pharmacology, Pharmacy and Toxicology, Merelbeke, Belgium.
authors.forename: P
authors.initials: P
authors.lastname: Van Eenoo
authors.forename: F T
authors.initials: FT
authors.lastname: Delbeke
authors.forename: K
authors.initials: K
authors.lastname: Roels
authors.forename: P
authors.initials: P
authors.lastname: De Backer
mesh_terms: D002138:Calibration; D002849:Chromatography, Gas / Q000379:methods*; D004300:Doping in Sports; D004809:Ephedrine / Q000652:urine*; D006801:Humans; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D015813:Substance Abuse Detection / Q000379:methods*
chemical_list: D004809:Ephedrine