An ion mobility-enabled and high-efficiency hybrid scan approach in combination with ultra-high performance liquid chromatography enabling the comprehensive characterization of the multicomponents from Carthamus tinctorius

Abstract

Liquid chromatography/mass spectrometry (LC/MS) is extensively applied for the untargeted/targeted analyses of the herbal components, utilizing data-dependent acquisition (DDA) or data-independent acquisition (DIA) to record the fragmentation information useful for the structural elucidation. A new trend recently has emerged by integrating DDA and DIA to render the hybrid scan, which, unfortunately, has rarely been reported. Herein, by using the Vion™ ion-mobility quadrupole time-of-flight mass spectrometer, a hybrid scan strategy (HDMS^E-HDDDA) was presented and validated by the untargeted characterization of the multicomponents from Carthamus tinctorius (safflower), in combination with reversed-phase ultra-high performance liquid chromatography (RP-UHPLC). Good chromatographic separation was achieved on an HSS T3 column within 26 min, while HDMS^E-MS/MS was used to acquire the collision-induced dissociation MS² data in the negative mode. Automatic workflows (e.g., data correction, precursors/product ions matching, and peak annotation) were well established on UNIFI™ (incorporating an in-house library recording 261 known compounds) to process the obtained MS² data. Compared with single DDA or DIA, the hybrid approach of HDMS^E-HDDDA better balanced between the coverage and reliability, led to high-definition MS spectra, offered useful collision cross section (CCS) information, and showed satisfactory identification performance comparable to MS^E. A total of 141 components (involving 41 quinochalcones, 66 flavanols/flavones, 11 flavanones, 6 organic acids, 1 polyacetylene, and 16 others) were characterized from safflower. Moreover, CCS prediction could assist isomers characterization, to some extent. Conclusively, this hybrid scan approach enables a dimension-enhanced MS data acquisition strategy providing the complementary structural information, which more suits the chemical characterization of complex samples.

Keywords: Carthamus tinctorius; Collision cross section; Hdmse-hddda; Ion-mobility/quadrupole time-of-flight mass spectrometry; Multicomponent characterization.