purity — 9 things I got wrong before I got it right
Thinking out loud about this: purity — 9 things I got wrong before I got it right. How to ask for a batch record without it turning into a negotiation. One email, three requests: the batch-specific certificate for lot X, the method line behind it, and the storage condition the stability statement was written against.…
Your name and address edited out of the screenshot above. The batch details are untouched and should stay.
ask for the storage condition the stability statement was written against
Did you get the chromatogram or only the summary line?
Did you get the chromatogram or only the summary line?
freya_baptista has the distinction right — one is a fraction of the detector signal, the other is a fraction of the mass.
My first certificate had a compound name, a percentage and a logo. I thought that was normal. It is not, and now I know what to ask for.
ask for the storage condition the stability statement was written against
This is the sentence to take away. The rest of the thread is footnotes to it.
the related substances line is where the story is
Correction: that is net peptide content, not purity. Different number, different meaning, and the document says so if you read the row label.
Area percent or net peptide content? They answer different questions.
Your name and address edited out of the screenshot above.
Agreed, and the practical version is: ask for the itemised table. If it exists, you get it.
Ask what the stability statement was written against — temperature, light, and whether it was the lyophilised powder or the reconstituted solution. Those are three different claims.