An impurity profile that changes between lots is more informative than the total. A stable profile suggests a controlled process; a shifting one suggests something is varying. Adding it because I spent an afternoon working it out and nobody should have to twice.
Posting this under the heading it deserves: Impurity thresholds: where the common numbers come from — what changed since Everything below is what sits behind that.
What changes if the standard account of Impurity thresholds is wrong? I ask because I have been treating it as settled and I noticed this week that I could not say why.
Working through the consequences rather than the evidence, since others here are better placed on the evidence.
An impurity profile that changes between lots is more informative than the total. A stable profile suggests a controlled process; a shifting one suggests something is varying.
Adding it because I spent an afternoon working it out and nobody should have to twice.
Useful. I had the fact and not the reason, which turns out to be the important half.
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Aggregates and why a purity assay may miss them entirely
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Named, unnamed and unspecified impurities as regulatory categories — the long version
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3 | 347 | 24d | |
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Where impurities in solid-phase peptide synthesis come from
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+54 | 59 | 14k | 3mo |
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2 | 59 | 3mo | |
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2 | 47k | 18mo | |
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MS/MS sequence confirmation: what it costs and when it is worth it — what changed since
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