title: Simultaneous quantification of loureirin A and loureirin B in rat urine, feces, and bile by HPLC-MS/MS method and its application to excretion study.
abstract: A simple HPLC-MS/MS method for simultaneous determination of loureirin A and loureirin B in rat urine, feces, and bile after oral administration of 10.6 g/kg of longxuejie (one rare traditional Chinese medicinal herb) was developed for the first time. The analytes and buspirone (internal standard) were separated on a C(5) column with acetonitrile-water (containing 0.1% formic acid) as mobile phase at a flow rate of 0.4 min/mL. The detector was a Q-trap™ mass spectrometer with an electrospray ionization interface operating in the multiple reaction monitoring mode. Calibration curves of loureirin A in rat urine, feces, and bile were linear over the concentration range of 1.00-5,000 ng/mL. Loureirin B in rat urine, feces, and bile ranged between 0.08 and 20, 0.20 and 20, and 0.10 and 500 ng/mL, respectively. Validation revealed that the method was specific, accurate, and precise. The fully validated method was applied to the excretion study of loureirin A and loureirin B in rats. After oral administration of 10.6 g/kg longxuejie, cumulative excretion amount of loureirin A and loureirin B in rat urine were 2.94 ± 0.81 and 0.36 ± 0.16 μg at 72 h, respectively. Of the total dose, 5.35% of loureirin A and 5.46% of loureirin B were excreted from feces at 60 h. The cumulative amounts of loureirin A and loureirin B in rat bile reached 4.49 ± 0.98 and 5.11 ± 0.83 μg, respectively, at 36 h after dosing, accounting for 0.054% and 0.056% of the total dose.
authors: School of Life Science, Beijing Institute of Technology, China.
authors: Yushi
authors: Y
authors: Zhang
authors: Yongzhi
authors: Y
authors: Li
authors: Bo
authors: B
authors: Chen
authors: Yulin
authors: Y
authors: Deng
authors: Yujuan
authors: Y
authors: Li
mesh_terms: D000818:Animals; D001646:Bile / Q000737:chemistry; D047188:Chalcones / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D005243:Feces / Q000737:chemistry; D029001:Herbal Medicine; D051381:Rats; D012116:Resins, Plant / Q000032:analysis*; D053719:Tandem Mass Spectrometry / Q000379:methods*; D014556:Urine / Q000737:chemistry
chemical_list: D047188:Chalcones; D012116:Resins, Plant; C560420:loureirin A; C505764:loureirin B