title: A sensitive LC-MS/MS method to quantify loureirin B in rat plasma with application to preclinical pharmacokinetic studies.
abstract: A novel method for the quantification of loureirin B in rat plasma using high-performance liquid chromatography/tandem mass spectrometry (LC-MS/MS) was developed. Loureirin B and internal standard (buspirone) were extracted by liquid-liquid extraction and separated on a Agilent XDB C18 column (50 mm x 4.6 mm, 5 microm). As mobile phase a binary mixture of methanol (containing 0.1% formic acid)-water (containing 0.1% formic acid) was delivered by a Shimadzu LC-20AD pump in gradient mode at a flow rate of 0.4 ml/min in a run time of 5.0 min. The detector was a Q-trap mass spectrometer with an electrospray ionization (ESI) interface operating in the multiple reaction monitoring (MRM) mode. The calibration curve of loureirin B in plasma showed good linearity over the concentration range of 0.08-100 ng/ml. The limit of detection and limit of quantification were 0.03 ng/ml and 0.08 ng/ml, respectively. Intra- and inter-day precisions (as relative standard deviation) in all samples were both within 15%. The validated method was successfully applied to a preliminary pharmacokinetic study of loureirin B in rats. After oral administration of 16 g/kg longxuejie to rats, the main pharmacokinetic parameters tmax, Cmax, t(1/2), Ke and AUC(0-T) were 0.8 h, 7.99 microg/l, 1.94 l h, 0.365/h, and 22.21 microg h/l, respectively.
authors: School of Life Science and Technology, Beijing Institute of Technology, No. 5 Zhongguancun South Street, Beijing 100081, China. lylyj2001@yahoo.com.cn
authors: Yujuan
authors: Y
authors: Li
authors: Yongzhi
authors: Y
authors: Li
authors: Zhezhe
authors: Z
authors: Yang
authors: Nian
authors: N
authors: Xin
authors: Yulin
authors: Y
authors: Deng
mesh_terms: D000818:Animals; D019540:Area Under Curve; D002138:Calibration; D002626:Chemistry, Pharmaceutical / Q000379:methods*; D002853:Chromatography, Liquid / Q000379:methods*; D005260:Female; D005561:Formates / Q000737:chemistry; D008297:Male; D013058:Mass Spectrometry / Q000379:methods*; D008956:Models, Chemical; D010949:Plasma / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D015203:Reproducibility of Results; D012116:Resins, Plant / Q000493:pharmacokinetics*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods; D013678:Technology, Pharmaceutical / Q000379:methods; D014867:Water / Q000737:chemistry
chemical_list: D005561:Formates; D012116:Resins, Plant; D014867:Water; C030544:formic acid; C505764:loureirin B