The simultaneous determination of coumarins in Angelica gigas root by high performance liquid chromatography–diode array detector coupled with electrospray ionization/mass spectrometry

Abstract

An high performance liquid chromatography–diode array detector coupled with electrospray ionization/mass spectrometry (HPLC–DAD/MS) based method has been developed for the simultaneous determination of nine coumarin compounds, nodakenin ( 1), peucedanone ( 2), marmesin ( 3), decursinol ( 4), 7-hydroxy-6-(2 R-hydroxy-3-methylbut-3-enyl)coumarin ( 5), demethylsuberosin ( 6), decursin ( 7), decursinol angelate ( 8) and isoimperatorin ( 9) in the Korean medicinal herb, Cham-Dang-Gui, the dried root of Angelica gigas (Umbelliferae). The methanol extracts were analyzed by HPLC using a reversed-phase C18 column (5 μm, 4.5 mm × 250 mm) using a gradient acetonitrile–water solvent system at a flow rate of 1.0 ml/min. The analysis of six coumarins ( 1, 3, 4 and 6– 8) with DAD was done at 330 nm and showed excellent linearity ( r 2 = 0.998–0.999) in a range of 0.2–250 μg/ml for all the compounds. The average recoveries ( n = 3) were between 96.5% and 110.8%. Identification of each peak was also discussed with the electrospray ionization multi-stage tandem mass spectroscopy (ESI-MS n ). The amount of these coumarin compounds was evaluated in A. gigas samples. Meanwhile, three coumarins ( 2, 5 and 9) could not been quantified by DAD because these peaks were overlapped with others. Determination of these compounds could be successfully accomplished with the HPLC–ESI/MS in selected ion monitoring/selected reaction monitoring mode.