title: UPLC-MS/MS determination of doxazosine in human plasma.
abstract: A sensitive, selective and rapid method for the analysis of doxazosine (DOX) in human plasma based on ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) is described. DOX and tamsulosin, used as an internal standard (IS), were extracted by liquid-liquid extraction, and the chromatography was performed on a C18 UPLC column packed with 1.7 mum particles. The total run time was 2 min. Detection was achieved by the multiple reaction monitoring of the following transitions: m/z 452-->344 and m/z 409-->228 for DOX and IS, respectively. Transitions of m/z 452-->247 and m/z 409-->271 were also collected for confirmation purposes. The calibration curve based on peak area ratio was linear up to at least 100 ng ml(-1), with a detection limit of 0.02 ng ml(-1) (a signal-to-noise ratio of 3). The method showed satisfactory reproducibility, and the short-term stability of the analyte was assessed. The method was successfully applied to the analysis of DOX in human plasma.
authors.affiliation: National Laboratory for Newborn Screening, King Faisal Specialist Hospital and Research Centre, P.O. Box 3354 (MBC-03), Riyadh, 11211, Saudi Arabia.
authors.forename: Osama Y
authors.initials: OY
authors.lastname: Al-Dirbashi
authors.forename: Hassan Y
authors.initials: HY
authors.lastname: Aboul-Enein
authors.forename: Minnie
authors.initials: M
authors.lastname: Jacob
authors.forename: Khalid
authors.initials: K
authors.lastname: Al-Qahtani
authors.forename: Mohamed S
authors.initials: MS
authors.lastname: Rashed
mesh_terms: D002853:Chromatography, Liquid / Q000379:methods; D017292:Doxazosin / Q000097:blood*; D006801:Humans; D013058:Mass Spectrometry / Q000379:methods*; D004364:Pharmaceutical Preparations / Q000032:analysis; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
chemical_list: D004364:Pharmaceutical Preparations; D017292:Doxazosin