"Target Ion Ratio Window" setting can impact peak integration - WKB81659

SYMPTOMS

• A target ion peak is not integrated in TargetLynx
• All compound, integration, and target ion properties are set correctly

ENVIRONMENT

• MassLynx
• TargetLynx

CAUSE

There is a slight difference in retention time between the "Quan ion" and the "First target ion", due to bad peak shape for example. If this retention time difference is smaller than the value displayed for "Target Ion Ratio Window (mins)", no peak integration will occur. This is logical but unexpected for many users.

FIX or WORKAROUND

1. Ensure that the value for "Target Ion Ratio Window (mins)" is set at zero or at a value higher than any possible retention time difference between the "Quan ion" and the "First target ion".

ADDITIONAL INFORMATION

As seen in the example below, there is no integration when the "Target Ion Ratio Window (mins)" is at 0.01 min and the actual retention time difference in the chromatograms is 0.02 min.

When the "Target Ion Ratio Window (mins)" is set at zero or a high enough value, peak integration is okay (see below).