Constant Neutral Loss Mode - Waters Xevo TQ-S Operator's, Overview And Maintenance Manual

Typical application
You typically use MRM mode to quantify known analytes in complex samples:
• Drug metabolite and pharmacokinetic studies.
• Environmental, for example, pesticide and herbicide analysis.
• Forensic or toxicology, for example, screening for target drugs in sport.
MRM mode does not produce a spectrum, because only one transition is
monitored at a time. As in SIR mode, a chromatogram is produced.

Constant neutral loss mode

Constant neutral loss mode detects the loss of a specific neutral fragment or
functional group from an unspecified precursor(s).
The scans of MS1 and MS2 are synchronized. When MS1 transmits a specific
precursor ion, MS2 "looks" to see whether that precursor loses a fragment of a
certain mass. If it does, the loss registers at the detector.
In constant neutral loss mode, the spectrum shows the masses of all
precursors that actually lost a fragment of a certain mass.
Constant neutral loss mode:
Typical application
You typically use constant neutral loss mode to screen mixtures for a specific
class of compound that is characterized by a common fragmentation pathway,
indicating the presence of compounds containing a common functional group.
MS1
Scanning
(synchronized with MS2)
Collision cell MS2
Pass all masses Scanning
(synchronized with MS1)
MS/MS operating modes 1-17