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Introduction
Scan Types
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Surveyor MSQ Plus Hardware Manual
Thermo Scientific
Scan Types
The Surveyor MSQ Plus MS detector provides two scan types:
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Selected Ion Monitoring (SIM) (SIM)
Full Scan
A full scan provides a mass spectrum over a defined mass range. Because the MS detector has
to monitor multiple
m/z
values during a chromatographic run, a full scan does not provide the
sensitivity that SIM provides. The faster the chromatographic peaks elute the lower the
sensitivity.
Selected Ion Monitoring (SIM)
In
selected ion monitoring (SIM), you specify the monitoring of a particular ion or set of ions.
Because only a few ions are monitored during a chromatographic run, SIM can provide lower
detection limits than a full scan analysis. If you need to detect small quantities of a target
compound, use SIM if you know the mass spectrum of your target compounds and the mass
spectrum of the sample matrix.
SIM can improve the detection limit for quantitative analyses, but it can also reduce
specificity. In SIM, only specific ions are monitored. Therefore, any compound that produces
those ions appears to be the target compound, resulting in false positives.
Data Types
The Surveyor MSQ Plus MS detector provides three data types:
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From the Xcalibur data system, you can acquire and display mass spectral data (intensity
versus mass-to-charge ratio) in two of these data types (peak formats): Profile or Centroid.
From the Tune window, you can acquire and display mass spectral data in all three data types.
