Use the Isotope Exclusion filter to exclude isotopes of a selected precursor from also being selected for a data-dependent scan within a given cycle. This filter reduces redundant MS/MS acquisition.
The following table describes the parameters in the Isotope Exclusion Properties pane.
Parameter | Description |
|---|---|
Assigned | Only excludes isotopes that were assigned on-the-fly. |
Assigned and unassigned | Excludes isotopes that were assigned on-the-fly and to also exclude a defined m/z window around precursors that the system was not able to assign isotopes for. |
Exclusion window (m/z) for unassigned isotopes | (Available when the Isotope Exclusion is set to Assigned and unassigned.) Define the exclusion window (m/z) for the precursors with unassigned isotopes. This will exclude the entire window, when the isotopes are not assigned, and may result in exclusion of other precursors if they are also present in the window. This option is often used when isolation windows are narrow and the resultant isotopic distribution is altered or when non-standard isotopic distribution are expected. Range: 0–20; default: 3 |