title: Determination of bencycloquidium bromide in rat plasma by liquid chromatography-electrospray ionization-mass spectrometry.
abstract: A liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS) assay for the determination of bencycloquidium bromide (BCQB) in rat plasma was firstly developed and validated. After addition of 1-ethyl-bencycloquidium bromide as an internal standard (I.S.), the plasma samples were deproteinized with methanol and the supernatant was assayed by LC-ESI-MS. Chromatographic separation was achieved with a Hanbon Lichrospher 5-C18 column. The mobile phase consisted of methanol-40 mM ammonium acetate buffer-formic acid (75:25:0.25, v/v/v) and delivered at the flow rate of 1.0 ml/min. LC-ESI-MS was carried out on a single quadrupole mass spectrometer using electrospray ionization (ESI) and positive selected-ion monitoring (SIM). Target ions were monitored at [M](+)m/z 330.2 for BCQB and [M] (+)m/z 344.2 for I.S. Calibration curve was linear over the range of 3-1500 ng/ml. The lower limit of quantification (LLOQ) was 3.0 ng/ml. The intra- and inter-run relative standard deviations (R.S.D.%) of the assay were less than 7.1 and 12.3%, respectively. The accuracy determined at the concentrations of 3.0, 100.0, 500.0 and 1500 ng/ml for BCQB were within +/-15.0%. The established method has been applied successfully to study the pharmacokinetics of BCQB in rats after intranasal administration.
authors.affiliation: Department of Pharmaceutical Analysis, China Pharmaceutical University, 24 Tongjiaxiang, Nanjing 210009, China.
authors.forename: Qin
authors.initials: Q
authors.lastname: Xu
authors.forename: Li
authors.initials: L
authors.lastname: Ding
authors.forename: Wenying
authors.initials: W
authors.lastname: Liu
authors.forename: Xiaojie
authors.initials: X
authors.lastname: Bian
authors.forename: Wenming
authors.initials: W
authors.lastname: Tang
mesh_terms: D000818:Animals; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000097:blood* / Q000493:pharmacokinetics; D002138:Calibration; D018680:Cholinergic Antagonists / Q000097:blood* / Q000493:pharmacokinetics; D002853:Chromatography, Liquid / Q000379:methods*; D051381:Rats; D012015:Reference Standards; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
chemical_list: D019086:Bridged Bicyclo Compounds, Heterocyclic; D018680:Cholinergic Antagonists; C518439:bencycloquidium bromide