Applied Biosystems Data Explorer 4 Series, User Manual

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Chapter 3 Peak Detection and Labeling
3-48 Applied Biosystems
3
Using the
Deisotope
function
To use the Deisotope function:
1. Display the spectrum trace of interest.
2. Make sure peak detection thresholds are set low enough
to detect the monoisotopic peak before deisotoping. If the
detection thresholds are not set low enough, adjust them.
For information, see Section 3.2.3, Setting Peak Detection
Parameters.
If you are analyzing digest data, set %Max Peak Area
to 0 before deisotoping to ensure that all peaks of
interest are detected. For more information, see
Section 7.2.3, Detecting Peaks from Complex Digests.
3. If multiply charged peaks are present, convert to a singly
charged spectrum. See Section 5.10, Converting to a
Singly Charged Spectrum (Mariner Data Only).
4. Select Duplicate Active Trace from the Display menu to
keep the original data displayed after processing.
5. From the Peaks menu, select Peak Deisotoping.
The Deisotoping dialog box (Figure 3-18) is displayed.
Figure 3-18 Deisotoping Dialog Box
6. In the Adduct text box, type the adduct that is the
charge-carrying species in the spectrum you are
examining.