title: Liquid chromatography-tandem mass spectrometric assay for the nucleoside reverse transcriptase inhibitor emtricitabine in human plasma.
abstract: A liquid chromatography-tandem mass spectrometric assay for the determination of the antiretroviral nucleoside emtricitabine in human plasma was developed and validated using a simple sample pre-treatment procedure. After addition of 5'-deoxy-5-fluorocytidine as the internal standard and protein precipitation with acetonitrile, the supernatant was directly injected in the isocratic chromatographic system using a polar embedded reversed-phase column and formic acid in water-methanol as the eluent. The eluate was completely led into an electrospray interface with positive ionization and the analytes were quantified using triple quadrupole mass spectrometry. The assay was validated in the range 5-5000 ng/mL. Intra-day precisions were <or=7% and inter-day precisions were <or=10%. Accuracies between 92 and 99% were found. The analytes were chemically stable under all relevant conditions and the assay was applied in the analysis of plasma samples of HIV-infected patients treated with the drug.
authors.affiliation: Utrecht University, Faculty of Science, Department of Pharmaceutical Sciences, Section of Biomedical Analysis, Division of Drug Toxicology, Sorbonnelaan 16, 3584 CA Utrecht, The Netherlands. R.W.Sparidans@pharm.uu.nl
authors.forename: Rolf W
authors.initials: RW
authors.lastname: Sparidans
authors.forename: Jan M
authors.initials: JM
authors.lastname: Prins
authors.forename: Jan H M
authors.initials: JH
authors.lastname: Schellens
authors.forename: Jos H
authors.initials: JH
authors.lastname: Beijnen
mesh_terms: D002853:Chromatography, Liquid / Q000379:methods; D003841:Deoxycytidine / Q000031:analogs & derivatives* / Q000097:blood; D000068679:Emtricitabine; D006801:Humans; D015394:Molecular Structure; D012015:Reference Standards; D015203:Reproducibility of Results; D018894:Reverse Transcriptase Inhibitors / Q000097:blood*; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D018894:Reverse Transcriptase Inhibitors; D003841:Deoxycytidine; D000068679:Emtricitabine