title: A less sensitive detector does not necessarily result in a less sensitive method: fast quantification of 13 antiretroviral analytes in plasma with liquid chromatography coupled with tandem mass spectrometry.
abstract: BACKGROUND
  We previously developed a method for the simultaneous determination of the human immunodeficiency protease inhibitors: amprenavir, atazanavir, darunavir, indinavir, lopinavir, nelfinavir, ritonavir, saquinavir and tipranavir, the active nelfinavir metabolite M8 the non-nucleoside reverse transcriptase inhibitors efavirenz, nevirapine and etravirine and the internal standards dibenzepine, (13)C(6)-efavirenz, D5-saquinavir and D6-indinavir in plasma using liquid chromatography coupled with tandem mass spectrometry with a Sciex API3000 triple quadrupole mass spectrometer and an analytical run time of only 10 min. We report the transfer of this method from the API3000 to a supposedly less sensitive Sciex API365 mass spectrometer.
  
  
  METHODS
  We describe the steps that were undertaken to optimize the sensitivity and validation of the method that we transferred.
  
  
  CONCLUSIONS
  We showed that transfer of a method to a putative less sensitive detector did not necessarily result in a less sensitive assay, and this method can be applied in laboratories where older mass spectrometers are available. Ultimately, the performance of the method was validated. Accuracy and precision was within 87%-110% and <13%, respectively. No notable loss in selectivity was observed.
authors.affiliation: Department of Pharmacy and Pharmacology, Slotervaart Hospital, Amsterdam, The Netherlands. rob@terheine.nl
authors.forename: Rob
authors.initials: R
authors.lastname: Ter Heine
authors.forename: Hilde
authors.initials: H
authors.lastname: Rosing
authors.forename: Jos H
authors.initials: JH
authors.lastname: Beijnen
authors.forename: Alwin D R
authors.initials: AD
authors.lastname: Huitema
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D017320:HIV Protease Inhibitors / Q000097:blood*; D006801:Humans; D018894:Reverse Transcriptase Inhibitors / Q000097:blood*; D053719:Tandem Mass Spectrometry / Q000295:instrumentation* / Q000379:methods
chemical_list: D017320:HIV Protease Inhibitors; D018894:Reverse Transcriptase Inhibitors