Topic summary

Residual solvents and scavengers: what is looked for

Analytics › Impurities & related substances counter-ion content HPLC data table forced degradation Solved

This is a generated summary. It shows the 5 most-liked posts from a topic of 24, in their original order, with the accepted answer included where one exists. It is a reading aid and it will miss nuance — the full topic is the record.

k.perrinTL215 Mar 2025#4

Off-target structures: if the sequence synthesis goes wrong, a completely different amino acid can be incorporated. The resulting off-target peptide is a structural isomer with the same mass but a different sequence. No chromatographic purity method detects this without a reference standard.

The reasoning is more useful than the number, which is why I have shown it.

21 likes 16mo

r.erdoganTL2 Solution23 Mar 2025#6

The confident answers on residual solvents and scavengers and the well-sourced answers are not the same answers, which is the most useful thing I have learned reading this category.

12 likes 16mo

s.okaforTL230 Mar 2025#8

Worth separating two things that post #4 runs together.

Worth separating residual solvents and scavengers as a question about the compound from residual solvents and scavengers as a question about the documentation. They get answered by different people and only one of them is answerable here.

28 likes 16mo

s.perrinTL29 Apr 2025#11

a.batista, post #3: Taking the opening post at face value and following it one step further. I would put moderate confidence on the mainstream reading of residual solvents and scavengers and no more. That is not scepticism for its own sake; it is where the sourcing actually stops. Go to post

A supplier that can tell you what its principal impurity is has answered a harder question than one that can tell you its purity, and the answer is more useful.

20 likes in reply to #3 16mo

t.waldenstrmTL2Member29 Apr 2025#18

The arithmetic in post #15 is right; the assumption feeding it is the part to check.

Residual solvents and scavengers is a question about a distribution, not about a value, and treating it as a value is what produces the confident wrong answers.

29 likes 15mo

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Particulates in a reconstituted solution: identifying the likely source — what changed sinceAnalytics › Impurities & related substances · 2 replies

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