Simultaneous determination of five phenolic components and paeoniflorin in rat plasma by liquid chromatography-tandem mass spectrometry and pharmacokinetic study after oral administration of Cerebralcare granule(®).

A simple, sensitive and selective high-performance liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) method was developed for simultaneous determination and pharmacokinetic study of six active components, protocatechuic acid, chlorogenic acid, caffeic acid, ferulic acid rosmarinic acid and paeoniflorin in rat plasma after oral administration of Cerebralcare granule(®) for the first time. The method involves a simple liquid-liquid extraction with ethyl acetate. The separation was performed on a Luna C18 column (2.0×100mm i.d., 3.0μm, particle, Phenomenex, USA) with gradient elution using a mobile phase composed of acetonitrile and water (containing 0.1% formic acid) at a flow rate of 0.2ml/min. Electrospray ionization (ESI) in negative ion mode and selective reaction monitoring (SRM) was used for the quantification of six active components and internal standard (IS, Chloroamphenicol). The method was linear for all analytes over investigated range with all correlation coefficients greater than 0.9914. The lower limits of quantification (LLOQ) were 1.0ng/ml for protocatechuic acid, 1.0ng/ml for chlorogenic acid, 1.0ng/ml for caffeic acid, 5.0ng/ml for ferulic acid, 1.5ng/ml for rosmarinic acid and 6.0ng/ml for paeoniflorin, respectively. The intra- and inter-day precisions (R.S.D.%) were less than 6.60% and 11.68%, and accuracy (RE %) between -3.26% and 1.13% (n=6). The developed method was applied for the first time to the pharmacokinetic study of protocatechuic acid, chlorogenic acid, caffeic acid, ferulic acid, rosmarinic acid and paeoniflorin in rat plasma after oral administration of Cerebralcare granule(®).