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What does 95.2% purity on a C18 column actually tell me about a semaglutide vial?

Asked 23 Jun 2025Modified 13 months agoViewed 17k times
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Stated plainly: 95.2% · a C18 column · semaglutide.

I have read the primary source rather than the summary, which has left me with more questions.

I understand the headline. I do not understand the footnotes, and the footnotes look important.

How should I read this, and where are the traps?

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askedpascal_thibault11k1723 Jun 2025
2Add the gradient and the column if you have them — half the answer depends on those. – per_haugen 9 months ago
3Same question came up on a different supplier and the answer was entirely about the method. – rota_site 15 days ago
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