title: Sensitive method for the determination of paricalcitol by liquid chromatography and mass spectrometry and its application to a clinical pharmacokinetic study.
abstract: A highly sensitive, specific and rapid LC-ESI-MS/MS method has been developed and validated for the quantification of paricalcitol (PAR) in human plasma (500 μL) using paricalcitol-d6 (PAR-d6 ) as an internal standard (IS) as per regulatory guidelines. A liquid-liquid extraction method was used to extract the analyte and IS from human plasma. Chromatography was achieved on Zorbax SB C18 column using an isocratic mobile phase in a gradient flow. The total chromatographic run time was 6.0 min and the elution of PAR and PAR-d6 occurred at ~2.6 min. A linear response function was established for the range of concentrations 10-500 pg/mL in human plasma. The intra- and inter-day accuracy and precision values for PAR met the acceptance criteria. The validated assay was applied to quantitate PAR concentrations in human plasma following oral administration of 4 µg capsules to humans.
authors.affiliation: Novel Laboratories Inc., Somerset, NJ-08852, USA.
authors.forename: Kishore Kumar
authors.initials: KK
authors.lastname: Hotha
authors.forename: Ramesh
authors.initials: R
authors.lastname: Mullangi
authors.forename: Ravindranath
authors.initials: R
authors.lastname: Lakshmanarao Krishnarao
authors.forename: Swapan
authors.initials: S
authors.lastname: Roychowdhury
mesh_terms: D000284:Administration, Oral; D002117:Calcitriol / Q000097:blood; D002138:Calibration; D002853:Chromatography, Liquid / Q000295:instrumentation / Q000379:methods*; D004355:Drug Stability; D004872:Ergocalciferols / Q000008:administration & dosage / Q000032:analysis / Q000097:blood* / Q000493:pharmacokinetics*; D006801:Humans; D059625:Liquid-Liquid Extraction; D008297:Male; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D053719:Tandem Mass Spectrometry / Q000295:instrumentation / Q000379:methods*
chemical_list: D004872:Ergocalciferols; C084656:paricalcitol; D002117:Calcitriol
keywords: 19-nor-1,25-dihydroxyvitamin D2; LC-MS/MS; human plasma; method validation; paricalcitol; pharmacokinetics