1-10 Waters TQ Detector
MS operating modes
The following table shows the MS operating modes.
The MS1 mode, in which MS1 is used as the mass filter, is the most common
and most sensitive method of performing MS analysis. It is directly analogous
to using a single-quadrupole mass spectrometer.
The MS2 mode of operation is used to provide optimum performance when
scan speeds exceed 2000 Da/s. It also provides a useful tool for instrument
tuning and calibration before MS/MS analysis and for fault diagnosis. See the
instrument online Help for further information on optimizing the TQ Detector
for fast MS scanning.
The selected ion recording (SIR) mode of operation is used as a quantitation
mode when no suitable fragment ion can be found to perform a more specific
multiple reaction monitoring (MRM) analysis.
Rule: Only chromatograms—not spectra—are generated when acquiring in
SIR mode.
MS operating modes
Operating mode MS1 Collision cell MS2
MS1 Resolving
(scanning)
Pass all masses
MS2 Pass all masses Resolving
(scanning)
SIR Resolving (static) Pass all masses