Determination of atractylon in rat plasma by a GC–MS method and its application to a pharmacokinetic study☆

A sensitive and selective method based on gas chromatography hyphenated to mass spectrometry (GC-MS) was developed and validated for the determination of atractylon in rat plasma. Plasma samples were processed by liquid-liquid extraction with ethyl acetate-n-hexane (1:1, v/v) using acetophenone as an internal standard (IS). Analytes were determined in selective ion monitoring (SIM) mode using target ions at m/z 108.1 for atractylon and m/z 105.1 for acetophenone. The calibration curve was linear over the concentration range of 10-1000 ng/mL with lower limit of quantification of 10 ng/mL. The intra- and inter-day precision variations were not more than 10.4% and 9.6%, respectively, whilst accuracy values ranged from -6.5% to 4.9%. Extraction recovery of the assay was satisfactory. This method was successfully applied to quantification and pharmacokinetic study of atractylon in rat plasma after intragastric administration of Atractylodis extract.