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scans (in MS mode) the background for all other components. RADAR mode enables fast
characterization of potential matrix effects, providing a platform for more robust method
development.
1.6.5.1
Typical application
You typically use RADAR mode during method development before performing MRM or PICS
analyses to quantify known analytes in complex samples:
•
Drug metabolite and pharmacokinetic studies
•
Environmental analysis: for example, for pesticides and herbicides
•
Forensic or toxicologic analysis: for example, screening for target drugs in sports
MRM analysis with no associated RADAR or PICS operation does not produce a spectrum
because only one transition is monitored at a time. As with SIR mode, however, a chromatogram is
produced.
1.6.6
Constant neutral-loss mode
Constant neutral-loss mode detects the loss of a specific neutral fragment or functional group from
an unspecified precursor or precursors.
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.
Figure 1–7:
1.6.6.1
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.
Constant neutral-loss mode
MS1
Scanning
(synchronized with MS2)
September 7, 2016, 715003560IVD Rev. C
Page 28
Collision cell
MS2
Fragmenting precursor
Scanning
ions and passing all
(synchronized with MS1)
masses
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