title: Liquid chromatography-tandem mass spectrometric assay for the mutated BRAF inhibitor vemurafenib in human and mouse plasma.
abstract: A bioanalytical assay for the mutated BRAF inhibitor vemurafenib was developed and validated. For the quantitative assay, human plasma samples were pre-treated using protein precipitation with water-acetonitrile (1/3, v/v) containing sorafenib as internal standard. The extract was directly injected into the chromatographic system. This system consisted of a sub-2 μm particle, trifunctional bonded octadecyl silica column with isocratic elution using 0.01% (v/v) of formic acid in a mixture of water and methanol. The eluate was transferred into the electrospray interface with positive ionization and the analyte was detected in the selected reaction monitoring mode of a triple quadrupole mass spectrometer. The assay was validated in a 0.1-100 μg/ml calibration range. Within day precisions were 1.6-3.2%, between day precisions 2.7% and 8.2% and accuracies were between 99% and 106% for the whole calibration range. The drug was stable under all relevant conditions. Finally, the assay was successfully used to assess drug levels in a pharmacokinetic mouse study.
authors.affiliation: Utrecht University, Faculty of Science, Department of Pharmaceutical Sciences, Division of Pharmacoepidemiology & Clinical Pharmacology, Utrecht, The Netherlands. R.W.Sparidans@uu.nl
authors.forename: Rolf W
authors.initials: RW
authors.lastname: Sparidans
authors.forename: Selvi
authors.initials: S
authors.lastname: Durmus
authors.forename: Alfred H
authors.initials: AH
authors.lastname: Schinkel
authors.forename: Jan H M
authors.initials: JH
authors.lastname: Schellens
authors.forename: Jos H
authors.initials: JH
authors.lastname: Beijnen
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000097:blood / Q000493:pharmacokinetics; D002853:Chromatography, Liquid / Q000379:methods*; D004355:Drug Stability; D006801:Humans; D007211:Indoles / Q000097:blood* / Q000493:pharmacokinetics; D051379:Mice; D047428:Protein Kinase Inhibitors / Q000097:blood* / Q000493:pharmacokinetics; D048493:Proto-Oncogene Proteins B-raf / Q000037:antagonists & inhibitors*; D012044:Regression Analysis; D015203:Reproducibility of Results; D013449:Sulfonamides / Q000097:blood* / Q000493:pharmacokinetics; D053719:Tandem Mass Spectrometry / Q000379:methods*; D000077484:Vemurafenib
chemical_list: D000970:Antineoplastic Agents; D007211:Indoles; D047428:Protein Kinase Inhibitors; D013449:Sulfonamides; D000077484:Vemurafenib; C482119:BRAF protein, human; D048493:Proto-Oncogene Proteins B-raf