Development and validation of a LC-ESI–MS/MS method for the determination of swertiamarin in rat plasma and its application in pharmacokinetics

• Published in: Journal of chromatography. B, Analytical technologies in the biomedical and life sciences Analytical technologies in the biomedical and life sciences, 2011-06, Vol.879 (19), p.1653-1658
• Main Authors: Li, Hong-Liang, Peng, Xiao-Jin, He, Jian-Chang, Feng, En-Fu, Xu, Gui-Li, Rao, Gao-Xiong
• Format: Article
• Language: English
• Subjects: Acetic acid; Analysis; Analytical, structural and metabolic biochemistry; Animals; bioactive properties; Biological and medical sciences; chemical structure; Chromatography; Chromatography, Liquid - methods; Columns (structural); detection limit; Drug Stability; Eclipses; Extraction; Female; Flow rate; Fundamental and applied biological sciences. Psychology; General pharmacology; Hydrogen-Ion Concentration; ionization; Iridoid Glucosides - blood; Iridoid Glucosides - pharmacokinetics; LC-ESI–MS/MS; Linear Models; Male; Medical sciences; methanol; Methyl alcohol; Monitoring; oral administration; Pharmacokinetics; Pharmacology. Drug treatments; Pyrones - blood; Pyrones - pharmacokinetics; Rat plasma; Rats; Rats, Sprague-Dawley; Reproducibility of Results; Sensitivity and Specificity; solid phase extraction; spectrometers; Spectrometry, Mass, Electrospray Ionization - methods; Swertia; Swertiamarin; Tandem Mass Spectrometry - methods
• ISSN: 1570-0232; 1873-376X
• DOI: 10.1016/j.jchromb.2011.04.003

A new LC-ESI–MS/MS assay method has been developed and validated for the quantification of swertiamarin, a representative bioactive substance of Swertia plants, in rat plasma using gentiopicroside, an analog of swertiamarin on chemical structure and chromatographic action, as the internal standard (IS). The swertiamarin and IS were extracted from rat plasma using solid-phase extraction (SPE) as the sample clean-up procedure, and they were chromatographed on a narrow internal diameter column (Agilent ZORBAX ECLIPSE XDB-C 18 100 mm × 2.1 mm, 1.8 μm) with the mobile phase consisting of methanol and water containing 0.1% acetic acid (25:75, v/v) at a flow rate of 0.2 mL/min. The detection was performed on an Agilent G6410B tandem mass spectrometer by negative ion electrospray ionisation in multiple-reaction monitoring mode while monitoring the transitions of m/ z 433 [M+CH 3COO] − → 179 and m/ z 415 [M+CH 3COO] − → 179 for swertiamarin and IS, respectively. The lower limit of quantification (LLOQ) was 5 ng/mL within a linear range of 5–1000 ng/mL ( n = 7, r 2 ≥ 0.994), and the limit of detection (LOD) was demonstrated as 1.25 ng/mL (S/N ≥ 3). The method also afforded satisfactory results in terms of sensitivity, specificity, precision ( intra- and inter-day), accuracy, recovery, freeze/thaw, long-time stability and dilution integrity. This method was successfully applied to determination of the pharmacokinetic properties of swertiamarin in rats after oral administration at a dose of 20 mg/kg. The following pharmacokinetic parameters were obtained (mean): maximum plasma concentration, 1920.1 ng/mL; time to reach maximum plasma concentration, 0.945 h; elimination half-time, 1.10 h; apparent total clearance, 5.638 L/h/kg; and apparent volume of distribution, 9.637 L/kg.