title: Measurement of fexofenadine concentration in micro-sample human plasma by a rapid and sensitive LC-MS/MS employing protein precipitation: application to a clinical pharmacokinetic study.
abstract: A simple, rapid and sensitive liquid chromatography/positive ion electro-spray tandem mass spectrometry method (LC-MS/MS) was developed and validated for the quantification of fexofenadine with 100 microL human plasma employing glipizide as internal standard (IS). Protein precipitation was used in the sample preparation procedure. Chromatographic separation was achieved on a reversed-phase C(18 )column (5 microm, 100 x 2.1 mm) with methanol : buffer (containing 10 mmol/L ammonium acetate and 0.1% formic acid; 70 : 30, v/v) as mobile phase. The total chromatographic runtime was approximately 3.0 min with retention time for fexofenadine and IS at approximately 1.9 and 2.1 min, respectively. Detection of fexofenadine and IS was achieved by LC-MS/MS in positive ion mode using 502.1 --> 466.2 and 446.0 --> 321.1 transitions, respectively. The method was proved to be accurate and precise at linearity range of 1-600 ng/mL with a correlation coefficient (r) of > or =0.9976. The validated method was applied to a pharmacokinetic study in human volunteers following oral administration of 60 or 120 mg fexofenadine formulations, successfully.
authors.affiliation: Department of Clinical Pharmacology, Nanjing First Hospital of Nanjing Medical University, China.
authors.forename: Daqing
authors.initials: D
authors.lastname: Guo
authors.forename: Jianjun
authors.initials: J
authors.lastname: Zou
authors.forename: Yubing
authors.initials: Y
authors.lastname: Zhu
authors.forename: Sheng
authors.initials: S
authors.lastname: Lou
authors.forename: Hongwei
authors.initials: H
authors.lastname: Fan
authors.forename: Qun
authors.initials: Q
authors.lastname: Qin
mesh_terms: D000293:Adolescent; D000328:Adult; D002853:Chromatography, Liquid / Q000191:economics / Q000379:methods*; D005260:Female; D005590:Fractional Precipitation / Q000379:methods*; D039563:Histamine H1 Antagonists, Non-Sedating / Q000097:blood*; D006801:Humans; D016014:Linear Models; D008297:Male; D011506:Proteins / Q000737:chemistry; D012680:Sensitivity and Specificity; D053719:Tandem Mass Spectrometry / Q000191:economics / Q000379:methods*; D016593:Terfenadine / Q000031:analogs & derivatives* / Q000097:blood; D055815:Young Adult
chemical_list: D039563:Histamine H1 Antagonists, Non-Sedating; D011506:Proteins; D016593:Terfenadine; C093230:fexofenadine