Twelve reference standards (purity>98%) were pur-chased from Weikeqi (Sichuan, China). These standardswere isoscopoletin, scopoletin, 7-methoxycoumarin,7-hydroxycoumarin, isomeranzin, bergapten, tan-geretin, nobiletin, hesperidin, limonin, ferulic acidand bergamottin. Chromatographic-grade methanoland dichloromethane were purchased from WeikeqiBio-Technology (Sichuan, China). Formic acid and ACN(purity>99.9%) of HPLC-grade were provided by MerckKGaA (Darmstadt, Germany) and Thermo Fisher Scien-tific Inc. (NYSE:TMO), respectively. CO2(purity>99.9%)was provided by Messer Gas (Guangzhou, China). |