Identification of the tannins in traditional Chinese medicine Paeoniae Radix Alba by UHPLC-Q-Exactive Orbitrap MS

Paeoniae Radix Alba (PRA, dried root of Paeonia lactiflora Pall.) is a widely used as traditional Chinese medicine and tannins are one of their main bioactive ingredients. However, there are rarely systematically investigated in this study. This study aimed to establish a rapid, high selective, high sensitive and effective method based on UHPLC-Q-Exactive Orbitrap MS for simultaneous identification the tannins in PRA. Separation was performed on Thermo Scientific Hypersil GOLD™ aQ (100 mm × 2.1 mm, 1.9 μm) using gradient elution consist of 0.1% formic acid acetonitrile and 0.1% formic acid water as the mobile phase at a flow rate of 0.3 mL/min. The mass spectrometer was operated with Q-Exactive Orbitrap spectrometer in negative ion mode. Finally, a total of 106 constituents were identified in PRA by UHPLC-Q-Exactive Orbitrap MS, 75 of those were reported from PRA for the first time. This result laid the foundation for in-depth research on the material basis efficacy and provided scientific basis for the selection of quality marker of PRA.