Deisotoping a Spectrum

Peaks in original trace

If first three peaks are part of the same isotope cluster

Contribution to expected isotope ratio

by contaminant

If first three peaks are part of the same isotope cluster, but contaminant is also present

If two isotope clusters are present

Deisotoped trace

Increased amplitude of first peak indicates it is a monoisotopic peak

Peak that is not part of cluster

Increased amplitude of first peak indicates it is a monoisotopic peak

Contaminant

Peak that is not part of cluster

Increased amplitude of peaks indicate they are monoisotopic peaks

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Figure 3-17 Interpreting a Deisotoped Trace

Requirements The Deisotope function requires a singly charged spectrum. If the spectrum you are examining includes multiply charged peaks, use the Single-Charge Conversion function on the Process menu before using the Deisotope function. For information, see Section 5.10, Converting to a Singly Charged Spectrum (Mariner Data Only).

CAUTION

If you use the Deisotope function on multiply charged peaks, invalid results are reported.

Data Explorer™ Software User’s Guide

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