Quantitative determination of tramadol in human serum by gas chromatography-mass spectrometry.
A gas chromatographic-mass spectrometric method for the quantitative determination of tramadol in human serum, plasma or whole blood samples is described. The method involves the use of [2H2, 15N]tramadol hydrochloride as an internal standard and chemical ionization with isobutane, employing single-ion monitoring for quantification. It is specific, sensitive and precise, and has high accuracy. The within-run coefficient of variation is about 1% between 25 and 200 ng/ml and 1.8-2.9% at the lowest concentrations tested (6.25 and 12.5 ng/ml). The between-run coefficient of variation increases from 1.6% to 5.2% with decreasing concentration from 200 to 12.5 ng/ml. The calibration graphs were linear in the tested concentration range, and the accuracy of the assay was not dependent on the sample volume used. The detection limit was about 4 ng/ml for serum samples of 1 ml. The method proved suitable for pharmacokinetic studies. Its high sensitivity allows measurements of serum concentrations for at least 30 h after the single administration of therapeutic doses of tramadol hydrochloride.
D001711:Biotransformation; D001798:Blood Proteins / Q000032:analysis; D001826:Body Fluids / Q000032:analysis; D055598:Chemical Phenomena; D002621:Chemistry; D003511:Cyclohexanols / Q000097:blood*; D004355:Drug Stability; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D007700:Kinetics; D011485:Protein Binding; D012015:Reference Standards; D012997:Solvents; D014147:Tramadol / Q000032:analysis / Q000097:blood*
D001798:Blood Proteins; D003511:Cyclohexanols; D012997:Solvents; D014147:Tramadol