title: Determination of ephedrines in urine by gas chromatography-mass spectrometry.
abstract: A selective gas-liquid chromatographic method with mass spectrometry (GC-MS) for the simultaneous confirmation and quantification of ephedrine, pseudo-ephedrine, nor-ephedrine, nor-pseudoephedrine, which are pairs of diastereoisomeric sympathomimetic amines, and methyl-ephedrine was developed for doping control analysis in urine samples. O-Trimethylsilylated and N-mono-trifluoroacetylated derivatives of ephedrines--one derivative was formed for each ephedrine--were prepared and analyzed by GC-MS, after alkaline extraction of urine and evaporation of the organic phase, using d3-ephedrine as internal standard. Calibration curves, with r2>0.98, ranged from 3.0 to 50 microg/ml depending on the analyte. Validation data (specificity, % RSD, accuracy, and recovery) are also presented.
authors.affiliation: Doppling Control Laboratory of Athens, Olympic Athletic Center of Athens Spiros Louis, Maroussi, Greece.
authors.forename: M H
authors.initials: MH
authors.lastname: Spyridaki
authors.forename: C J
authors.initials: CJ
authors.lastname: Tsitsimpikou
authors.forename: P A
authors.initials: PA
authors.lastname: Siskos
authors.forename: C G
authors.initials: CG
authors.lastname: Georgakopoulos
mesh_terms: D002138:Calibration; D004809:Ephedrine / Q000652:urine*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D012015:Reference Standards; D015203:Reproducibility of Results
chemical_list: D004809:Ephedrine