title: Determination of natural corticosteroids in urine samples from sportsmen.
abstract: A method for the determination of natural corticosteroids (cortisone, cortisol, 5beta-dihydrocortisone, 5beta-dihydrocortisol, tetrahydrocortisone and tetrahydrocortisol) found in the urine of sportsmen, was developed using a capillary gas chromatography-mass spectrometry ion trap system. 17alpha-Methyltestosterone was used as an internal standard. The different corticosteroids were determined from the peak area ratios of the [M]; [M-90] and [M-90-90] fragment ions of their methoxime-trimethylsiyl derivatives. Sensitivity (15 ppb), specificity, accuracy (96%) and reproducibility (RSD=4-10%) of the method were demonstrated to be satisfactory for measuring the urinary concentrations of the selected natural corticosteroids.
authors.affiliation: Department of Analytical Chemistry and Electrochemistry, Faculty of Sciences, Extremadura University, Badajoz, Spain.
authors.forename: J J
authors.initials: JJ
authors.lastname: Rivero-Marabé
authors.forename: J I
authors.initials: JI
authors.lastname: Maynar-Mariño
authors.forename: M P
authors.initials: MP
authors.lastname: García-de-Tiedra
authors.forename: A M
authors.initials: AM
authors.lastname: Galán-Martín
authors.forename: M J
authors.initials: MJ
authors.lastname: Caballero-Loscos
authors.forename: M
authors.initials: M
authors.lastname: Maynar-Marinõ
mesh_terms: D000305:Adrenal Cortex Hormones / Q000652:urine*; D002138:Calibration; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D006801:Humans; D008297:Male; D012015:Reference Standards; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013177:Sports
chemical_list: D000305:Adrenal Cortex Hormones