Ultra-performance liquid chromatography coupled with electrospray ionization/quadrupole-time-of-flight mass spectrometry for rapid analysis of constituents of Suanzaoren decoction.

A rapid, sensitive, specific and reliable ultra-performance liquid chromatography coupled with electrospray ionization/quadrupole-time-of-flight mass spectrometry (UPLC-ESI-Q-TOF-MS) method with MassLynx™ MassFragment was developed for the analysis of Suanzaoren decoction (SZRD), a Chinese herbal prescription. The analysis was performed on a Waters UPLC BEH C(18) column using gradient elution system. A hyphenated electrospray ionization and Q-TOF analyzer was used for the determination of accurate mass of the protonated or deprotonated molecule and fragment ion in both negative and positive modes. The chromatographic separation was achieved by UPLC, which used a column with 1.7 μm particle packing which enabled higher speed of analysis, peak capacity, greater resolution and increased sensitivity. The constituents of SZRD were identied and confirmed according to the mass spectrometric fragmentation mechanisms, MS/MS fragment ions, relevant literature and the establishment of an in-house molecular formula database. With this method, a total of 22 compounds of SZTD were tentatively identied based on MS and MS/MS data and comparison with available databases. It is concluded that a rapid and robust platform based on UPLC-ESI-Q-TOF-MS was established, which is useful for identifying multiple-constituent of traditional Chinese medicine (TCM) prescriptions. Our present results proved that the established method could provide helpful chemical information for further pharmacological mechanism research of SZRD.