Topic summary
Relative retention time as a better inter-laboratory comparator — does this still hold?
This is a generated summary. It shows the 5 most-liked posts from a topic of 16, 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.
I had written a reply contradicting post #5 and deleted it. Here is what survived.
The most useful single question about a method: what would it fail to detect? Every method has an answer and few documents state it.
Scoping that to what I have actually seen rather than what I have read.
12 likes 23mo
Everything in post #5 holds. The case it does not cover is the one I have.
Relative retention time has been discussed here with more heat than it deserves, mostly because two definitions have been in play the whole time.
27 likes 23mo
e.almeida, post #1: Relative retention time as a better inter-laboratory comparator — does this still hold? I have a specific reason for asking rather than idle curiosity, and the context is below. What changes if the standard account of Relative retention time is wrong? I ask because I have been treating it as settled and I noticed this week that I could… Go to post
Everything in post #8 holds. The case it does not cover is the one I have.
Nobody has said the unglamorous part of Relative retention time yet, so: most of the variation is explained by things that are boring to write about and easy to check.
f.wojcik, post #14: System suitability is the ongoing evidence that a validated method is still performing. Validation is done once; suitability is done every run, and it is the one that appears on a certificate. I have no interest in any supplier named above. Go to post
Peak purity assessment using a diode-array detector checks whether a peak is spectrally homogeneous. It is a weak test and it is better than not looking.
Read the full topic (16 posts)
This topic was referenced in
- Why one laboratory's 98.4% and another's 96.1% may not contradictAnalytics › Method validation · 37 replies
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