June 13, 2012
by Arvin Moser, Team Manager, Application Scientists, ACD/Labs
To identify co-eluting components on a chromatogram, one searches for any distinct differences between the components.
There are basically three criteria to check the XICs (extracted ion chromatograms) for to confirm whether the m/z signals pertain to the same component: line shape, signal apex and retention time range. The XICs for m/z 188.1 and 205.1 show a similar line shape, a common apex and a comparable retention time range. Based on these three matches, the m/z 188.1 and 205.1 are most likely related to the same component.
However, we cannot rule out the case for co-elution of a binary mixture at 2.86 minutes. The lack of any differences from the XICs suggests two plausible explanations, either m/z 188.1 and 205.1 are part of the same component or there is a ‘perfect’ co-elution between the two components.