title: A sensitive LC-MS/MS assay for the simultaneous analysis of the major active components of silymarin in human plasma.
abstract: Silymarin, an extract of crushed achenes of the milk thistle plant Silybum marianum is a multi-constituent mixture, 70-80% of which consists of a complex assortment containing the flavonolignans silybin A and B, isosilybin A and B, silydianin, and silychristin, and the flavonoid taxifolin. To date, numerous pharmacological actions of the silymarin extract have been documented in the biomedical literature, including hepatoprotective, anti-inflammatory, anti-tumor, and anti-fibrotic activities. The present study describes a novel liquid chromatographic-tandem mass spectrometric method for simultaneous analysis of silychristin, silydianin, silybin A and silybin B, isosilybin A and isosilybin B, and taxifolin in human plasma employing liquid-liquid extraction. This assay provides excellent resolution of the individual silymarin constituents via utilization of a 100 A 250 mm × 2 mm, 5 μm C(18) column with the mobile phase consisting of 51% methanol, 0.1% formic acid, and 10mM ammonium acetate. The lower limit of quantification was 2 ng/ml for each constituent. Calibration curves were linear over the range from 2 ng/ml to 100 ng/ml for all analytes (r(2)>0.99). The intra- and inter-day accuracies were 91-106.5% and 95.1-111.9%, respectively. The intra- and inter-day precision was within 10.5%. Additionally, recovery, stability, and matrix effects were fully validated as well. This method was successfully applied to human plasma samples from subjects treated with the milk thistle extract Legalon(®).
authors: Department of Pharmacotherapy and Translational Research, University of Florida, Gainesville, FL 32610-0486 , USA.
authors: Bryan J
authors: BJ
authors: Brinda
authors: Hao-Jie
authors: HJ
authors: Zhu
authors: John S
authors: JS
authors: Markowitz
mesh_terms: D002853:Chromatography, Liquid / Q000379:methods*; D004355:Drug Stability; D005260:Female; D006801:Humans; D059625:Liquid-Liquid Extraction; D008297:Male; D020944:Silybum marianum; D010936:Plant Extracts; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012838:Silymarin / Q000097:blood* / Q000737:chemistry / Q000493:pharmacokinetics; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D010936:Plant Extracts; D012838:Silymarin