title: Highly sensitive and rapid determination of theophylline, theobromine and caffeine in human plasma and urine by gradient capillary high-performance liquid chromatography-frit-fast atom bombardment mass spectrometry.
abstract: A sensitive and reliable analytical procedure has been established for the detection of theophylline (TH), theobromine (TB) and caffeine (CA) in human plasma and urine by gradient capillary high-performance liquid chromatography (HPLC)-frit-fast atom bombardment mass spectrometry (FAB-MS) (LC-frit-FAB-MS). Two capillary columns and a column-switching valve were used in this LC system to allow all of the sample injected to be introduced into the MS system. 7-Ethyltheophylline was used as the internal standard (I.S.). The xanthines in the specimen were extracted with an Extrelut column. The lowest detected amount was ca. 5 ng/ml using this method.
authors.affiliation: Department of Forensic Medicine, Fukuoka University School of Medicine, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Hieda
authors.forename: S
authors.initials: S
authors.lastname: Kashimura
authors.forename: K
authors.initials: K
authors.lastname: Hara
authors.forename: M
authors.initials: M
authors.lastname: Kageura
mesh_terms: D002110:Caffeine / Q000032:analysis* / Q000097:blood / Q000652:urine; D002197:Capillary Action; D002851:Chromatography, High Pressure Liquid / Q000379:methods* / Q000706:statistics & numerical data; D006801:Humans; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016339:Spectrometry, Mass, Fast Atom Bombardment / Q000379:methods* / Q000706:statistics & numerical data; D013805:Theobromine / Q000032:analysis* / Q000097:blood / Q000652:urine; D013806:Theophylline / Q000032:analysis* / Q000097:blood / Q000652:urine
chemical_list: D002110:Caffeine; D013806:Theophylline; D013805:Theobromine