Ultra performance liquid chromatography-MS/MS analysis
A high-resolution tandem mass spectrometer TripleTOF5600plus (SCIEX, UK)
was used to detect metabolites eluted from the column, operated in both
positive and negative ion modes. The parameters were curtain gas 30
pounds per square inch (PSI); Ion source gas1 60 PSI; Ion source gas2 60
PSI; interface heater temperature 650 ℃; Ion spray voltage 5000 V for
positive ion mode, -4,500V for negative ion mode. The mass spectrometry
data were acquired in IDA mode. Four time bins were summed for each scan
at a pulser frequency value of 11 kHz through monitoring of the 40 GHz
multichannel TDC detector with four-anode/channel detection. The mass
accuracy was calibrated every 20 samples during the acquisition with 4 s
for dynamic exclusion. A quality control sample (Pool of all samples)
was acquired after every 10 samples for evaluating the stability of the
LC-MS.