Simultaneous determination of seven components in Citri Exocarpium Rubrum by UPLC-MS/MS

An ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was established for the simultaneous determination of seven components (chlorogenic acid, rutin, narirutin, hesperidin, sinensetin, nobiletin, tangeretin) in Citri Exocarpium Rubrum. The separation was performed over 12.0 min on a Shim-pack GIST C18 column (100 mm×2.1 mm, 2.0 μm) with a mobile phase consisting of acetonitrile (A) and 0.1% formic acid water solution (B) with gradient elution at a flow rate of 0.4 mL·min^-1; the column temperature was 30℃ and the injection volume was 1 μL. Detection was performed on a QTRAP 4500 mass spectrometer equipped with electrospray ionization. Positive and negative electrospray ionization was performed in multiple reaction monitoring mode. All of the analytes showed good linearity (r ≥ 0.997 3) in the tested ranges, with good precision, repeatability and stability for all analytes. The average recoveries were in the range of 99.32%-107.75% with relative standard deviations RSD ≤ 3.94%. The established method is accurate, stable and reproducible, and can provide a research method for the quality control of Citri Exocarpium Rubrum.