Topic summary

Water content on a certificate and why it changes the arithmetic

Analytics › COA interpretation certificate of analysis reference standards batch & lot numbers Closed

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j.nwosuTL2 Moderator22 Apr 2025#4

post #2 answers the question as asked. The question underneath it is different.

What fields matter on a certificate: lot number matching the vial, test date, the analytical method stated specifically, the measured result as a number, and the acceptance limit stated separately. A certificate missing any of these is weaker.

27 likes 15mo

j.mwangiTL4 Moderator28 Apr 2025 · edited#8

Staff post. Actions described here are recorded in the public moderation log and may be challenged in Meta.

When a document puts the specification in the result column, it has told you the release criterion, not the measurement. Those are different claims and the second is weaker.

20 likes 15mo

f.novakTL2 Moderator2 May 2025#11

Picking up post #8: that is the part I would want checked first.

I disagree with the reply above, and I think the disagreement is substantive rather than terminological.

The distinction being drawn does not survive when you look at the published data for this specific question. I would be glad to be shown wrong on this, because the version I am arguing against is more convenient.

31 likes 15mo

a.cardosoTL2 Moderator7 May 2025#15

Sterility testing is separate: chromatographic purity, mass spectrometry, and endotoxin testing all say nothing about whether a solution is sterile. If sterility matters, it needs to be tested and reported.

23 likes 15mo

NorringtonTL3Regular15 May 2025#22

f.novak, post #11: Picking up post #8: that is the part I would want checked first. I disagree with the reply above, and I think the disagreement is substantive rather than terminological. The distinction being drawn does not survive when you look at the published data for this specific question. I would be glad to be shown wrong on this, because the… Go to post

Picking up post #19: that is the part I would want checked first.

When a document puts the specification in the result column, it has told you the release criterion, not the measurement. Those are different claims and the second is weaker.

24 likes in reply to #11 14mo

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A field-by-field walk through a certificate of analysisAnalytics › COA interpretation · 147 replies

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