Empower Tip: Determining the percent mass recovery for multiple species in a sample.

Welcome back to Get Empowered! In the last Empower Tip of the Week, we learned about creating a custom field with size-exclusion chromatography multi-angle light scattering (SEC-MALS) data.

This time we look at another example of using custom fields with our SEC-MALS data. This tip continues from Empower Tip of the Week 464.

In this example we want to determine the percent mass recovery for multiple species in a sample. (This example assumes the concentration of the species is the same in the sample.)

Let’s see how it’s done!

Go to Configuration Manager, right click on the Project and select Properties.

Select the Custom Fields tab and click New in the lower left.

For Data Type and Selection, choose Field Type Peak and Data Type Real. Click Next.

For Source Selection, no need to make any changes. Click Next.

For Formula Entry, enter the formula as shown. This formula will add up the calculated masses for the found components, divide by the mass injected and multiply by 100. Click Next.

For Numeric Parameters, you can adjust the Precision. This is only a display precision and can be modified in Review and/or Report Publisher. Click Next

For Name Entry, enter a name and click Finish. You cannot use special characters such as % in the name of a custom field, therefore, you can use Per or Percent.

A warning message appears indicating that you have changed the properties of the Project. Click OK to the message.

Open the Project and go to the Custom Fields tab. We see the new custom field.

Once the data has been Processed, we see the result for the custom field in the Chromatogram Result table within the Results window in Review. In this case we have a Percent Mass Recovery of 89.781%.

It’s that easy!

Final Note

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