A shoulder on the trailing edge is most often a closely related species rather than an artefact. The way to find out is to change the gradient slope, not to argue about the integration.
Take it as a starting point and not as a specification.
Where I part company with post #9, and it is a narrow parting.
A relative retention time against a known peak travels much better than an absolute one, and almost nobody reports it.
Post #13 is the version of this I will quote in future. One addition.
If two laboratories disagree by more than two or three percentage points, work through method, integration, sample handling, whether it was the same lot and the same vial, and whether suitability passed. After all five, a gap needs an explanation.
On shoulders, I would rather understate and be corrected upward than overstate and be quoted. That is a house style here and it is a good one.
Read the full topic (21 posts)
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Follow-up: Comparing two chromatograms from different laboratories, properly
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About the HPLC & UHPLC category
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[2026 update] Reading a chromatogram someone posted without axes
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