Development and validation of a liquid chromatographic/electrospray ionization mass spectrometric method for the determination of benazepril, benazeprilat and hydrochlorothiazide in human plasma.
A new method was developed and fully validated for the quantitation of benazepril, benazeprilat and hydrochlorothiazide in human plasma. Sample pretreatment was achieved by solid-phase extraction (SPE) using Oasis HLB cartridges. The extracts were analysed by high-performance liquid chromatography (HPLC) coupled to a single-quadrupole mass spectrometer (MS) with an electrospray ionization interface. The MS system was operated in selected ion monitoring (SIM) modes. HPLC was performed isocratically on a reversed-phase porous graphitized carbon (PGC) analytical column (2.1 x 125.0 mm i.d., particle size 5 microm). The mobile phase consisted of 55% acetonitrile in water containing 0.3% v/v formic acid and pumped at a flow rate of 0.15 ml min(-1). Chlorthalidone was used as the internal standard (IS) for quantitation. The assay was linear over a concentration range of 5.0-500 ng ml(-1) for all the compounds analysed, with a limit of quantitation of 5 ng ml(-1) for all the compounds. Quality control (QC) samples (5, 10, 100 and 500 ng ml(-1)) in five replicates from three different runs of analyses demonstrated intra-assay precision (coefficient of variation (CV) < or =14.6%), inter-assay precision (CV < or = 5.6%) and overall accuracy (relative error less than -8.0%). The method can be used to quantify benazepril, benazeprilat and hydrochlorothiazide in human plasma, covering a variety of pharmacokinetic or bioequivalence studies.
University of Athens, School of Pharmacy, Division of Pharmaceutical Chemistry, Panepistimiopolis, Zografou 157 71, Athens, Greece.
Ariadni
A
Vonaparti
Michael
M
Kazanis
Irene
I
Panderi
D000959:Antihypertensive Agents / Q000032:analysis / Q000097:blood*; D001552:Benzazepines / Q000032:analysis / Q000097:blood*; D002138:Calibration; D002851:Chromatography, High Pressure Liquid / Q000379:methods* / Q000592:standards; D006801:Humans; D006852:Hydrochlorothiazide / Q000032:analysis / Q000097:blood*; D015203:Reproducibility of Results; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods* / Q000592:standards
D000959:Antihypertensive Agents; D001552:Benzazepines; D006852:Hydrochlorothiazide; C052133:benazeprilat; C044946:benazepril