title: Simultaneous Determination of Tramadol and Its Metabolite in Human Urine by the Gas Chromatography-Mass Spectrometry Method.
abstract: A sensitive and efficient method was developed for determination of tramadol and its metabolite (O-desmethyltramadol) in human urine by gas chromatography-mass spectrometry. Tramadol, O-desmethyltramadol and medazepam (internal standard) were extracted from human urine with a mixture of ethylacetate and diethylether mixture (1 : 1, v/v) at basic pH with liquid-liquid extraction. The calibration curves were linear (r = 0.99) over tramadol and O-desmethyltramadol concentrations ranging from 10 to 200 ng/mL and 7.5 to 300 ng/mL, respectively. The method had an accuracy of >95% and intra- and interday precision (relative standard deviation %) of ≤4.93 and ≤4.62% for tramadol and O-desmethyltramadol, respectively. The extraction recoveries were found to be 94.1 ± 2.91 and 96.3 ± 3.46% for tramadol and O-desmethyltramadol, respectively. The limit of quantification using 0.5 mL human urine was 10 ng/mL for tramadol and 7.5 ng/mL for O-desmethyltramadol. After oral administration of 100 mg of tramadol hydrochloride to a patient, the urinary excretion was monitored during 24 h. About 15% of the dose was excreted as unchanged tramadol.
authors.affiliation: Department of Analytical Chemistry, Faculty of Pharmacy, Ataturk University, Erzurum 25240, Turkey yilmazb@atauni.edu.tr.
authors.forename: Bilal
authors.initials: B
authors.lastname: Yilmaz
authors.affiliation: Department of Anesthesiology and Reanimation, Faculty of Medicine, Sakarya University, Sakarya 54187, Turkey.
authors.forename: Ali Fuat
authors.initials: AF
authors.lastname: Erdem
mesh_terms: D000701:Analgesics, Opioid / Q000652:urine*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D006801:Humans; D057230:Limit of Detection; D059625:Liquid-Liquid Extraction / Q000379:methods; D015203:Reproducibility of Results; D014147:Tramadol / Q000031:analogs & derivatives* / Q000652:urine*
chemical_list: D000701:Analgesics, Opioid; C080580:O-demethyltramadol; D014147:Tramadol