Empower Tip: Using custom fields with our SEC-MALS data

Welcome back to Get Empowered! In the last EmpowerTM Tip of the Week, we learned about using Molecular Weight Markers.

This time, we take a look at using custom fields with our SEC-MALS data. This tip continues from Empower Tip of the Week 463.

Let’s see how it’s done!

From the last tip we learned that Empower Software uses Molecular Weight Markers to calculate the percent area of the distribution that has molecular weights either above or below the molecular weight marker. If we want to determine the percent area of the distribution between 2 molecular weights, we can create a custom field for this determination.

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 sum all slice areas between 2 molecular weights and divide that by that total of all slice areas, then multiplied 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.

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.

Open the Processing Method and go to the MALS Component tab. Enter the molecular weights in the CConst1 and CConst2 fields.

Once the data has been Processed, we see the result for the custom field in the Peaks table in Review. In this case 33.99% of the area percentage of the overall distribution lies between 55,000 and 65,000.

It’s that easy!

Final Note

For more information, visit www.wyatt.com/products/software/empower.html or contact your Waters Informatics Sales Specialist.