Empower Custom Field and Named Groups

I have the following four components:
Single Peak 1
Single Peak 2
Single Peak 3
Named Group (which is a group of Peak 1, 2 and 3)

Each individual peak also has a unique RRF:
Peak 1 has an RRF of 1.0
Peak 2 has an RRF of 1.3
Peak 3 has an RRF of 1.5

The equation in my method is:
(Sample Total Peak Area) / (Std Total Peak Area) * (Std Conc / Sample Conc) * 100%
where Total Peak Area = (Peak 1 Area*1.0)+(Peak 2 Area*1.3)+(Peak 3 Area*1.5)

I created the following Peak custom field: (Area*CConst1)
CConst1 = the applicable RRF's listed above

In the component table, I set the "Y-value" to match the peak custom field name.

On an individual peak basis, everything works great.   My problem is the Named Group won't sum the three peak "Area x CConst" values.  What is happening is that the group area is being multiplied by the CConst1 value for that group (in this case 1.0).

Any thoughts for how I can get the Named Group to sum the "Area*CConst1" values?


  • I don't think you need custom fields for this. There are a few ways around this. There is an option in the Named Groups called "Source of Calibration X Value". So going back to your components tab for Peak 1, pick a curve reference of whatever the group peak is called, and leave the 1.00 in the RRF field, same for Peak 2 but select 1.3 for RRF and 1.5 for Peak 3. Leave the curve reference for the Group Peak blank, and in the Named Group tab select "Sum Peaks, Curve or Sum Peaks for Quantitation" as source of Calibration X Value. In your component editor, dont include the single peaks 1-3 in the Value tab, only put in the value for the Group Peak (so delete the individual peak entries In the component tab). Save the processing method and review some raw data for standard injections to check your values for Amount for Group peak and it should add up all the adjusted single peaks. 

    Also, there is a field in Empower 3 called Corrected Area which is Area* (value in Impurity RRF) so for Peak 1 put in 1 in Impurity RRF, and the other values as relevant. Set up your named group as usual in Named Groups tab and again pick the Sum Peaks, Curve or Sum Peaks as the option plus make sure to put Corrected Area as the Y-Value response. 
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