title: An isocratic high-performance liquid chromatographic system for simultaneous determination of theophylline and its major metabolites in human urine.
abstract: A simple and highly selective isocratic high-performance liquid chromatography method is presented for the simultaneous determination of theophylline and its major metabolites in human urine using beta-hydroxyethyl theophylline as an internal standard. The method utilizes direct injection of diluted urine samples followed by separation and quantitation by reversed-phase isocratic elution and ultraviolet detection. The assay is accurate and reproducible with a sensitivity of 1 microgram ml-1 for theophylline and 0.5 micrograms ml-1 for its metabolites. The assay was employed for the analysis of theophylline and its major metabolites in urine following the oral administration of theophylline to four healthy volunteers.
authors.affiliation: Biopharmacy Division, Tehran University of Medical Sciences, Iran.
authors.forename: H
authors.initials: H
authors.lastname: Tajerzadeh
authors.forename: S
authors.initials: S
authors.lastname: Dadashzadeh
mesh_terms: D000328:Adult; D001711:Biotransformation; D002138:Calibration; D002851:Chromatography, High Pressure Liquid; D005260:Female; D006801:Humans; D008297:Male; D010726:Phosphodiesterase Inhibitors / Q000493:pharmacokinetics / Q000652:urine*; D013806:Theophylline / Q000493:pharmacokinetics / Q000652:urine*
chemical_list: D010726:Phosphodiesterase Inhibitors; D013806:Theophylline