Topic summary

Reused chromatograms across lots: how to spot it — what changed since

Analytics › COA interpretation batch & lot numbers amino acid analysis reference standards documentation quality Solved

This is a generated summary. It shows the 6 most-liked posts from a topic of 40, in their original order, with the accepted answer included where one exists. It is a reading aid and it will miss nuance — the full topic is the record.

l.piresTL2 Solution5 Dec 2025#4

glossary_desk, post #1: Reused chromatograms across lots: how to spot it — what changed since — setting out what I have, and where I think it stops being reliable. What changes if the standard account of Reused chromatograms across lots is wrong? I ask because I have been treating it as settled and I noticed this week that I could not say why. Working through… Go to post

I read the earlier replies on Reused chromatograms across lots twice before writing this, because I had assumed the opposite and wanted to be sure I was disagreeing with what was said rather than what I expected.

18 likes in reply to #1 8mo

ThibodeauTL3Regular29 Dec 2025 · edited#8

l.solberg, post #2: A note on how Reused chromatograms across lots gets discussed rather than on Reused chromatograms across lots itself: the confident posts get the replies and the careful ones get ignored, and the careful ones have been right more often. Go to post

Bookmarking this. I will come back when I have something worth adding.

25 likes in reply to #2 7mo

a.amankwahTL214 Jan 2026#11

Building on post #9 rather than restating it.

Reused chromatograms across lots has been discussed here with more heat than it deserves, mostly because two definitions have been in play the whole time.

32 likes 6mo

p.friskTL27 Mar 2026#22

Confirming post #19 from a second method, which matters more than confirming it from a second person.

The distinction between release testing and characterisation is one industrial documents make and retail ones usually do not. It is the difference between "we tested every lot for this" and "we established this once".

25 likes 5mo

n.chowdhuryTL224 Mar 2026#26

The strongest argument against my own position on Reused chromatograms across lots, stated as well as I can state it, since nobody else has yet.

18 likes 4mo

aliquot_lineTL3Regular8 May 2026#37

e.tamm, post #19: An itemised related-substances table with retention times says considerably more about the synthesis than a single total. A total tells you how much is not the main peak and nothing about what it is. Not the answer, but possibly the question that gets there. Go to post

Reused chromatograms across lots is well covered in the tag pages, and the older discussions are better than the recent ones because they were argued out properly. Worth twenty minutes before adding to this one.

25 likes in reply to #19 3mo

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