Empower Tip #256 | Peak Purity (Part 6)

By December 15, 2021

Tip #256: How to Calculate the Solvent Angle

Welcome back! In this week’s tip for Empower Chromatography Data System (CDS), we will discuss how to calculate the Solvent Angle. (In last week’s tip, we discussed Peak Purity parameters for PDA data, Tip #255).

Continuing the discussion regarding AutoThreshold from last week (Tip #255), if the Purity Angle is greater than the Purity Threshold for any of the peaks in any of the standard injections, then you need to determine the Solvent Angle separately.

Let’s get started.

Step 1

On the Purity tab of the Processing Method, select ‘Noise’ from the ‘Threshold Criteria’ list (figure 1).

Figure 1 

Step 2

Process the same six injections of the standard that was used to verify AutoThreshold (figure 2).

Figure 2

Step 3

Select the ‘highest Purity Angle’ reported from the results (figure 3).

Figure 3

Step 4

Select ‘Noise+Solvent’ from the ‘Threshold Criteria’ list and enter the value from Step 3 into the ‘Solvent Angle (degrees)’ field. This value has a precision of 2 (figure 4).

Figure 4

Step 5

Save all the changes to the Processing Method and reprocess the six injections. Now the Purity Angle should be less than the Purity Threshold for all peaks in the standards (figure 5).

Figure 5


It’s that easy!

Final Note: This can be done with either the Pro or QuickStart interface.

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Next time in Empower Tip #257– we will continue our series on Peak Purity using both PDA and QDa Detectors.

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Categories: Empower Tips