title: High-performance liquid chromatography-electrospray ionization mass spectrometric determination of nisoldipine in human plasma.
abstract: A selective and sensitive high-performance liquid chromatography-electrospray ionization mass spectrometry (MS) for the determination of nisoldipine in human plasma is first presented. With nimodipine as the internal standard, nisoldipine is extracted from plasma with ethyl acetate. The organic layer is evaporated and the residue is resuspended in the mobile phase of methanol-water (80:20, v/v). An aliquot of 40 microL is chromatographically analyzed on an Agilent ODS C18 reversed-phase column (5 microm, 250- x 4.6-mm i.d.) by means of selected-ion monitoring mode MS. The calibration curve of nisoldipine in plasma exhibits a linear range from 0.5 to 20.0 ng/mL with a correlation coefficient of 0.9995. The limit of detection is 0.2 ng/mL. The within- and between-day variations (relative standard deviation) are less than 9.28% and 11.13% (n = 5), respectively. The developed method is validated through successful use for the analysis of nisoldipine contained in biological fluids resulting from a phase-I human pharmacokinetic study.
authors.affiliation: Center for Instrumental Analysis, China Pharmaceutical University, Nanjing 210009, PR China. zunjianzhang@hotmail.com
authors.forename: Zunjian
authors.initials: Z
authors.lastname: Zhang
authors.forename: Yuan
authors.initials: Y
authors.lastname: Tian
authors.forename: Li
authors.initials: L
authors.lastname: Ni
authors.forename: Jinheng
authors.initials: J
authors.lastname: Li
mesh_terms: D002121:Calcium Channel Blockers / Q000097:blood* / Q000493:pharmacokinetics; D002138:Calibration; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D018592:Cross-Over Studies; D006801:Humans; D008297:Male; D015737:Nisoldipine / Q000097:blood*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
chemical_list: D002121:Calcium Channel Blockers; D015737:Nisoldipine