A novel hybrid scan approach enabling the ion-mobility......

ABSTRACT

   Data-dependent acquisition (DDA) and data-independent acquisition (DIA)-based MSn strategies are extensively applied in metabolites characterization. DDA gives accurate MSn information, but receives low coverage, while DIA covers the entire mass range, but the precursor-product ions matching often yields false positives. Currently available MS scan approaches rarely integrate DIA and DDA within a dutycircle. Utilizing a Vion™IM-QTOF (ion mobility-quadrupole time-of-flight) mass spectrometer, we report a novel hybrid scan approach, namely HDDIDDA, which involves three scan events: 1) IM-enabled full scan (MS1), 2) high-definition MSE (HDMSE) of all precursor ions (MS2); and 3) high-definition DDA (HDDDA) of top N precursors (MS2). 

As a proof-of-concept, the HDDIDDA approach combined with offline two-dimensional liquid chromatography (2D-LC) was applied to characterize the multiple ingredients from a reputable Chinese patent medicine, Compound Danshen Dripping Pill (CDDP) used for  treating the cardiovascular diseases. An off-line 2D-LC system by configuring an XBridge Amide column and an HSS T3 column showed a measurable orthogonality of 0.92 and enhanced the separation of coeluting components. A fit-for-purpose HDDIDDA methodology was developed in the negative mode to characterize saponins and salvianolic acids, while tanshinones in the positive mode. Computational workflows to efficiently process the acquired HDMSE and HDDDA data were established, and the searching of an in-house CDDP library (recording 712 compounds) eventually characterized 403 components from CDDP, indicating approximate 12-fold improvement compared with the previous report. The HDDIDDA approach can measure collision cross section of each component, and merges the merits ofDIA and DDA in MS2 data acquisition.

Chemicals and reagents

Desite Biotechnology Co., Ltd. (Chengdu, China), were used as the reference compounds with their chemical structures and information detailed in Fig. S1 and Table S1, respectively.

原文链接：https://doi.org/10.1016/j.aca.2021.339320