What a certificate commits its issuer to posts 31–60
This is a continuation of a long topic, addressed by post number rather than by page. Start at post 1.
Asking for the batch record rather than the certificate is a reasonable request and the response to it is informative whichever way it goes.
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.
None of the above is medical advice and I am not qualified to give any.
Coming back to post #33, because the follow-up matters more than the original answer.
A chromatogram supplied as a small image is legible for peak shape and not for baseline detail. That is enough to sanity-check an integration and not enough to reproduce it.
I would call that likely rather than established.
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".
If anyone can point at the primary source I would be grateful.
I had written a reply contradicting post #36 and deleted it. Here is what survived.
"Not less than 98 per cent" is a specification. "98.3 per cent" is a result. A certificate carrying only the first has not told you what was measured.
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".
Adding the measurement that post #41 says would settle it.
Endotoxin testing is separate: a certificate of purity says nothing about endotoxin. A chemically pure preparation can carry a clinically significant endotoxin load. If endotoxin matters, it needs to be tested and reported.
Where I part company with post #41, and it is a narrow parting.
A chromatogram supplied as a small image is legible for peak shape and not for baseline detail. That is enough to sanity-check an integration and not enough to reproduce it.
It is the sort of thing that seems obvious in retrospect and was not at the time.
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.
The evidence for this is thinner than the way I have phrased it suggests.
Collapsed as off-topic by two members at trust level 3 or above
Answering the question post #41 raises rather than the one it answers.
A chromatogram supplied as a small image is legible for peak shape and not for baseline detail. That is enough to sanity-check an integration and not enough to reproduce it.
The arithmetic in post #44 is right; the assumption feeding it is the part to check.
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".
If that reads as pedantic, it is, and it has saved me twice.
Helpful, and easy to find again, which is half of what a good reply is.
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.
Written from notes rather than memory, which is why the numbers are specific.
A chromatogram supplied as a small image is legible for peak shape and not for baseline detail. That is enough to sanity-check an integration and not enough to reproduce it.
That has held every time I have looked, which is not the same as always.
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".
The honest answer is that it depends, and here is what it depends on.
Adding the measurement that post #48 says would settle it.
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.
It reads as pedantry until the day it does not.
Useful. I have added it to my own notes with the date on it.
A certificate of analysis is a statement by its issuer that a defined test was performed on a defined lot and produced a defined result. That is all it is, and it is not nothing. What makes it usable: lot identifier matching the container, test date, method identification specific enough to reproduce, the actual result as a number, and the acceptance criterion stated separately from the result.
Peptide content and chromatographic purity are separate determinations and a certificate that reports only one has answered only one question. Content is the one that tells you how much is in the vial.
I would treat the number as indicative rather than as a measurement.
The arithmetic in post #53 is right; the assumption feeding it is the part to check.
A certificate is a statement by its issuer that a defined test was performed on a defined lot and produced a defined result. That is all it is, and it is not nothing.
I would put this at better than even and not much better.
Answering the question post #54 raises rather than the one it answers.
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.
Adding this to the thread rather than to the wiki, because I am not confident enough for the wiki.
A chromatogram supplied as a small image is legible for peak shape and not for baseline detail. That is enough to sanity-check an integration and not enough to reproduce it.
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".
Following this. I have the same question and no better information than the first post.
Residual solvent screening is not standard on these documents and its presence is a signal about the manufacturer's own systems rather than about the vial.
That is where I would start, not where I would stop.