Time segment scanning-based quasi-multiple reaction monitoring mode by ultra-performance liquid chromatography coupled with quadrupole/time-of-flight mass spectrometry for quantitative determination of herbal medicines: Moutan Cortex, a case study

In this study, a time segment scanning-based quasi-multiple reaction monitoring (quasi-MRM) mode was proposed to improve the quantitative performance of UPLC-QTOF-MS/MS. To achieve the quasi-MRM mode, a strategy to select the ion pair (precursor and product ions) of each analyte was adopted as follows. First, a stable and abundant ion by quadrupole was set as precursor ion in MS scan mode. Second, the fragment ions of the precursor ion formed...