Deamidation at asparagine and glutamine: adds 1 approximately. Frequently appears as a close-eluting pair. It is a chemical modification that occurs during storage.
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Analytics · Impurities & related substances · continued
Endotoxin and why it is a separate question from purity — what changed since posts 91–92
This is a continuation of a long topic, addressed by post number rather than by page. Start at post 1.
e.mbeki, post #5: Residual solvents: traces of solvents used in purification. These are usually tested by gas chromatography, not by HPLC. A specification for residual solvents should be stated separately from the purity. Go to post
post #91 is right about the mechanism and I think understates the practical bit.
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.
This topic was referenced in
- Attributing a new peak: degradation product or excipient?Analytics › Impurities & related substances · 2 replies
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