title: Determination of etoricoxib in human plasma by liquid chromatography-tandem mass spectrometry with electrospray ionisation.
abstract: The validation of a liquid chromatography-tandem mass spectrometry (LC-MS-MS) method for the determination of the selective cyclooxygenase-2 inhibitor etoricoxib in human plasma with phenazone as internal standard is described. The plasma samples were extracted by solid-phase extraction using polymer-based cartridges. Chromatography was carried out on a short, narrow bore RP C(18) column (30x2 mm). Detection was achieved by a Sciex API 3000 triple quadrupole mass spectrometer equipped with a turbo ion spray source working in positive ion mode. The respective mass transitions used for quantification of etoricoxib and phenazone were m/z 359.2-->280.2 and m/z 189.0-->104.1. The analytical method was validated over the concentration range 0.2-200 ng/ml. The limit of quantification was 0.2 ng/ml. The method is applicable to pharmacokinetic studies in humans.
authors.affiliation: pharmazentrum frankfurt, Klinikum der Johann Wolfgang Goethe-Universität Frankfurt, Theodor Stern Kai 7, Haus 75, 60590 Frankfurt am Main, Germany.
authors.forename: Lutz
authors.initials: L
authors.lastname: Bräutigam
authors.forename: Jens U
authors.initials: JU
authors.lastname: Nefflen
authors.forename: Gerd
authors.initials: G
authors.lastname: Geisslinger
mesh_terms: D000983:Antipyrine / Q000097:blood; D002853:Chromatography, Liquid / Q000379:methods*; D016861:Cyclooxygenase Inhibitors / Q000097:blood* / Q000493:pharmacokinetics; D000077613:Etoricoxib; D006801:Humans; D011725:Pyridines / Q000097:blood* / Q000493:pharmacokinetics; D012015:Reference Standards; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D013450:Sulfones / Q000097:blood* / Q000493:pharmacokinetics
chemical_list: D016861:Cyclooxygenase Inhibitors; D011725:Pyridines; D013450:Sulfones; D000983:Antipyrine; D000077613:Etoricoxib