2000 MS Hardware Maintenance
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Chemical Ionization Options
Save the GC/MS Method.
Methods for Single CI Reagents
Open the standard GC/MS Method you have created and saved (e.g.,
EI_GC.mth) in the Saturn GC/MS Workstation. Before proceeding use the
Method Editor menu command
File… Save As
to save the file with a name
specific to the first CI reagent you want to use (e.g. ACN_CI for acetonitrile CI).
Then choose the Method Directory item Sample Delivery to turn on the External
Event for that CI gas:
Click on the Add button on the right of the window to add another segment and
enter 30 under Time so that External Event A will be turned Off again at the end
of the run. In the following example, it is assumed that acetonitrile is in Channel A
of the MCI Module, which is activated from Valve 1.
NOTE: It is always a good idea to close the chosen Channel of the MCI Module
at the end of a run so that the foreline pump is isolated from the CI reagent
.
Otherwise, the reagent will be pumped continuously from the Channel until it is
exhausted
.
