title: Simultaneous quantitation of dexamethasone palmitate and dexamethasone in human plasma by liquid chromatography/tandem mass spectrometry.
abstract: A rapid and sensitive liquid chromatography/tandem mass spectrometry (LC/MS/MS) method for simultaneous quantitation of dexamethasone palmitate and dexamethasone in human plasma was developed. After sample preparation by protein precipitation and liquid-liquid extraction, the analytes and internal standard (IS) were separated on a Venusil XBP-C8 column using gradient elution. Multiple reaction monitoring of dexamethasone palmitate, dexamethasone and IS used the precursor to product ion transitions at m/z 631.8-->373.1, m/z 393.2-->147.1 and m/z 264.2-->58.1, respectively. The method was linear over the ranges 1.5-1000ng/mL for dexamethasone palmitate and 2.5-250ng/mL for dexamethasone with intra- and inter-day precisions of <10% and accuracies of 100+/-7%. The assay was applied to a clinical pharmacokinetic study involving the injection of dexamethasone palmitate to healthy volunteers.
authors.affiliation: Research Center for Drug Metabolism, College of Life Science, Jilin University, Changchun 130021, PR China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Yang
authors.forename: Hao
authors.initials: H
authors.lastname: Li
authors.forename: Kan
authors.initials: K
authors.lastname: Gao
authors.forename: Mingyuan
authors.initials: M
authors.lastname: Liu
authors.forename: Yantong
authors.initials: Y
authors.lastname: Sun
authors.forename: Tingting
authors.initials: T
authors.lastname: Yan
authors.forename: J Paul
authors.initials: JP
authors.lastname: Fawcett
authors.forename: Yimin
authors.initials: Y
authors.lastname: Cui
authors.forename: Jingkai
authors.initials: J
authors.lastname: Gu
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D003907:Dexamethasone / Q000097:blood* / Q000493:pharmacokinetics; D006801:Humans; D012015:Reference Standards; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D003907:Dexamethasone