A rapid and eco-friendly method for determination of dictamnine, obacunone, and fraxinellone in Cortex Dictamni by LC–MS and matrix solid-phase dispersion extraction

This study develops a rapid and eco-friendly liquid chromatography–mass spectrometry method for determining dictamnine, obacunone, and fraxinellone in Cortex Dictamni. The samples were extracted by matrix solid-phase dispersion extraction with ethanol. The liquid chromatography separation was operated on an Agilent InfinityLab Poroshell 120 EC-C18 column (2.1 mm × 30 mm, 2.7 μm) using 45% ethanol at a 0.3 mL/min flow rate. Mass spectrometry detection was set at positive ion mode, and the selected ion monitoring mode was used to record the target compounds: dictamnine (mass-to-charge ratio 200), obacunone (mass-to-charge ratio 455), and fraxinellone (mass-to-charge ratio 233). The calibration curves exhibited good linearity (R > 0.9994) within the test range. The intra-day precision was 0.601% for dictamnine, 1.03% for obacunone, and 0.898% for fraxinellone. The recoveries were 100% for dictamnine, 101% for obacunone, and 96.2% for fraxinellone. Six samples were analyzed, and they all conformed to the content requirements of the Chinese Pharmacopeia. Notably, the developed method only requires 6.07 mL ethanol and costs 12 min. This study presents a rapid and eco-friendly analytical method for determining three components in Cortex Dictamni, which will help improve the quality evaluation technology of Cortex Dictamni.