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c/coa·submitted 1 year ago by u/kavya_verhoeven

the batch question that gets asked weekly, answered properly

Explainerbranch of 7 comments

the batch question that gets asked weekly, answered properly. I have gone back and forth on this for months. Asked for the storage condition behind the stability statement. Got it in a sentence. It is a two-line email and almost nobody sends it. The PDF creation date being later than the analysis date is usually a…

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7 comments, started 1 year ago
u/ignacio_silva11 points·1 year ago

Related substances itemised individually is a much stronger document than a single total, because it tells you the shape of the impurity profile rather than its size.

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u/kavya_verhoevenOP7 points·1 year ago

What does the method line actually say? Not the technique — the column and the gradient.

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u/bastian_moreau2 points·1 year ago

the related substances line is where the story is

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u/kavya_verhoevenOP1 point·1 year ago

Batch number and date of analysis, are both on there?

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u/amara_halonen1 point·1 year ago

Did you ask for the batch-specific document, or is this the catalogue one?

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u/stablecoin_steve1 point·1 year ago

Spent four months confusing area% and mass% in every post I made here. One explainer thread and it clicked permanently.

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[removed]4 points·1 year ago

[removed by moderator]

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About c/coa

How to read a certificate of analysis and what it does and does not tell you. Area% versus mass%, identity versus quantity, water content, related substances, acetate counterions, and the difference between a vendor-supplied COA and an independent test on the vial you actually received.

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