Rapid and sensitive screening of GSH-trapped reactive metabolites using MRM-dependent MS/MS scan on a triple quadruple-linear ion trap mass spectrometer

摘要

The neutral loss (NL) scan of 129 Da on a triple quadrupole mass spectrometer is often employed for analyzing reactive metabolites trapped by GSH. However, this method suffers low sensitivity and limited selectivity. To improve the effectiveness of GSH adduct screening by LC/MS, methods using stable-isotope labeled GSH as a trapping agent, high resolution LC/MS, and precursor ion (PI) scan in the negative ionization mode have been applied. The present study describes a new analytical approach for rapid and sensitive analysis of GSH-trapped reactive metabolites using MRM as the survey scan to trigger acquisition of enhanced product ion (EPI) spectra on QTRAP (Figure 1). The results from the MRM-EPI approach were compared with those from the NL and PI scanning analyses.