title: A sensitive and specific liquid chromatography/tandem mass spectrometry method for determination of echinacoside and its pharmacokinetic application in rats.
abstract: A rapid and sensitive method based on liquid chromatography/tandem mass spectrometry (LC/MS/MS) for the determination of echinacoside in rat plasma was established and fully validated. A single step of liquid-liquid extraction with n-butanol was utilized. Chromatographic separation of the analyte and the internal standard (IS), chlorogenic acid, from the sample matrix was performed using a Capcell-MG C(18) analytical column (100 2.0 mm x 5 microm), with a gradient of acetonitrile and water containing 0.1% acetic acid as the mobile phase. Detection was performed on a triple quadrupole tandem mass spectrometer equipped with electrospray ionization source operated in negative ion selected reaction monitoring mode. The method was linear in the concentration range 10-2500 ng/mL. The deviations of both intra- and inter-day precisions (RSD) were 7.1% and the assay accuracies were within 99.2-106.5%. Echinacoside proved to be stable during sample storage, preparation and analysis when an antioxidant solution was used. The method was successfully applied to a pharmacokinetic study in rats after an intragastric administration of echinacoside (100 mg/kg). With the lower limit of quantification at 10 ng/mL, this method proved to have sufficient selectivity, sensitivity and reproducibility for the pharmacokinetic study of echinacoside.
authors.affiliation: Key Laboratory of Drug Metabolism and Pharmacokinetics, China Pharmaceutical University, Nanjing 210038, People's Republic of China.
authors.forename: Hao
authors.initials: H
authors.lastname: Yang
authors.forename: Guangji
authors.initials: G
authors.lastname: Wang
authors.forename: Haiping
authors.initials: H
authors.lastname: Hao
authors.forename: Pengfei
authors.initials: P
authors.lastname: Tu
authors.forename: Yong
authors.initials: Y
authors.lastname: Jiang
authors.forename: Qiong
authors.initials: Q
authors.lastname: Wang
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhang
authors.forename: Chaonan
authors.initials: C
authors.lastname: Zheng
authors.forename: Yuxin
authors.initials: Y
authors.lastname: Wang
authors.forename: Liang
authors.initials: L
authors.lastname: Dai
mesh_terms: D020001:1-Butanol / Q000737:chemistry; D000818:Animals; D002726:Chlorogenic Acid / Q000097:blood; D002853:Chromatography, Liquid / Q000191:economics / Q000379:methods*; D006027:Glycosides / Q000097:blood* / Q000493:pharmacokinetics*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D012680:Sensitivity and Specificity; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods; D053719:Tandem Mass Spectrometry / Q000191:economics / Q000379:methods*; D013997:Time Factors
chemical_list: D006027:Glycosides; D002726:Chlorogenic Acid; D020001:1-Butanol; C060297:echinacoside