Empower Tip: Peak Identification

In this tip for Empower Chromatography Data System (CDS), we will continue our series on peak identification.

In this tip, we learn how to deal with peaks that are either not identified or misidentified due to shifting Retention Times. We will start with adjusting Retention Time (RT) windows.

The Processing Method is developed with a standard and the peaks are named accordingly.

We run a sample and see that there is a peak at 8.033 minutes which has a Peak Type Unknown. Peaks 3 and 4 display Peak Type Missing.

We know in this case that the peak at 8.033 minutes is Peak 3. Clicking the Show Components tool in the lower toolbar displays the expected Retention Time for Peak 3 and the RT window. The apex of this peak is outside of the window resulting in the Peak Type Unknown.

A possible solution is to increase the RT window. If the peak(s) are well separated, then you can increase the RT window. There are three ways to do this:

Change the RT window % value – this is a global parameter and will affect the RT window for all peaks.

Change the RT window for an individual component in the table.

Change the RT window for an individual component in the chromatogram by clicking the show components tool to display the window and moving either the start or end marker for the window. The table will be updated automatically.

The peak is now properly identified.

It’s that easy!