Empower Tip: QDa MS Data in Empower

In this tip. we will learn about injection-based expected mass processing. In this example, we want to determine if a specified mass is present in the sample. The advantages of doing it this way are that you do not need to identify peaks in the processing method, and you can search for masses that account for adducts resulting from sample matrix interactions.

Let’s see how it’s done!

Right-click on the Sample Set and bring it to Alter Sample. Enter the expected mass or masses in the Target Mass field(s). NOTE: Alternatively, you could do this in Run Samples before you acquire data.

Create a simple Processing Method for peak detection and integration. On the MS Expected Mass tab click the radio button for Injection-based processing. Check the box that reads, Include the uncorrected Target or Base Mass in the list of expected masses. The Peak Separation is described in Tip 364.

If you do not make this selection you will need to specify at least one adduct. To specify an adduct, select the ionization mode that has the adduct and enter adduct delta mass.

In the Method Set, add the Default Processing Method and click the Expected Mass Processing button at the bottom of the window.

Select the 3D MS channel in the Channel Name field and the Processing Method, then click OK.

Process the 3D MS channel using the Method Set and go to the Results tab.

Bring the new Results into Review. Label the peaks with Base Peak so you can compare the mass found versus the Target Mass which is found in the Channel Description.

It’s that easy!