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

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-(2R-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 (r2 = 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-MSn). 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.