Rapid characterisation of flavonoids from Sophora alopecuroides L. by HPLC/DAD/ESI-MS n

An HPLC/DAD/ESI-MS n method was established to characterise flavonoids in the seeds of Sophora alopecuroides L. All the flavonoids exhibited abundant [M−H]− ions, which triggered data-dependent multistage mass spectrometry fragmentations. Characteristic UV spectra were used to confirm flavonoid subtypes. In total, 22 flavonoids and two phenolic compounds were detected and identified. Five of them were identified by comparing with reference standards, and the others were characterised based on the retention behaviour, multistage fragmentation feature and UV absorption. A total of 19 compounds were reported from S. alopecuroides for the first time. This method accomplished rapid profiling of flavonoid constituents in S. alopecuroides L.