What Is the SCIEX OS Software Equivalent to the Area Threshold Feature in Analyst® Software?

For research use only. Not for use in diagnostic procedures.

Answer

In Analyst® software, users can set criteria for peaks to appear as "Not found" in a results table; peaks above the area limit are integrated, while peaks that don't meet the criteria are ignored and listed as "Not found" or "No peak detected" in the results table. To enable this in Analyst software, users define a value for the Area Threshold field in the quantitation method wizard in Quantitation mode. This field can be used to filter out peaks that are below either the detection limit or the quantitation limit.

This Area Threshold field is not available when creating a quantitation method in SCIEX OS software, but a similar type of filtering can be set up in the Flagging Rules section of the quant method wizard. Select the Add a Rule option and then select Custom Rule from the drop down menu. A new screen will appear where a customized rule can be added to the quant method. To create a rule that will alert the user that there are integrated peaks below their desired cut-off value for area, enter the following parameters:

In the example above, the peak area threshold for all components has been set to 40,000 cps. (Individual flagging criteria for each component can also be set.) When this is incorporated into a processing method, any peak below that value will be flagged in the results table in a blue box (see below):