title: Determination of the unstable drug otilonium bromide in human plasma by LC-ESI-MS and its application to a pharmacokinetic study.
abstract: Otilonium bromide (OB) degrades rapidly in plasma and readily undergoes hydrolysis by the plasma esterase. In this paper, an LC-ESI-MS method has been developed for the determination of OB in human plasma. The rapid degradation of OB in plasma was well prevented by immediate addition of potassium fluoride (KF, an inhibitor of plasma esterase) to the freshly collected plasma before prompt treatment with acetonitrile. The method was validated over the concentration range of 0.1-20ng/ml. The data of intra-run and inter-run precision and accuracy were within ±15%. The mean extraction recoveries for OB and the internal standard were higher than 93.0% and the matrix effects were negligible. The method has been successfully used in a pharmacokinetic study.
authors.affiliation: Department of Pharmaceutical Analysis, China Pharmaceutical University, 24 Tongjiaxiang, Nanjing 210009, China.
authors.forename: Yan-Rong
authors.initials: YR
authors.lastname: Zhao
authors.forename: Li
authors.initials: L
authors.lastname: Ding
authors.forename: Hong-Wei
authors.initials: HW
authors.lastname: Fan
authors.forename: Yong
authors.initials: Y
authors.lastname: Yu
authors.forename: Xie-Min
authors.initials: XM
authors.lastname: Qi
authors.forename: Ye
authors.initials: Y
authors.lastname: Leng
authors.forename: Ya-Kun
authors.initials: YK
authors.lastname: Rao
mesh_terms: D000097:Acetonitriles / Q000737:chemistry; D002853:Chromatography, Liquid / Q000379:methods*; D004355:Drug Stability; D005459:Fluorides / Q000737:chemistry; D006801:Humans; D016014:Linear Models; D008297:Male; D017680:Potassium Compounds / Q000737:chemistry; D000644:Quaternary Ammonium Compounds / Q000097:blood* / Q000737:chemistry / Q000493:pharmacokinetics; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
chemical_list: D000097:Acetonitriles; D017680:Potassium Compounds; D000644:Quaternary Ammonium Compounds; C013934:octylonium; C033320:potassium fluoride; D005459:Fluorides; C032159:acetonitrile