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How many vials from a CPC lot should I send for an HPLC purity test?

Asked 8 Nov 2025Modified 9 months agoViewed 3.7k times
8

The case in front of me: CPC · an HPLC purity test.

I want the working, not the result — I need to be able to redo it with different numbers.

I care about the precision as well as the value — I want to know how many figures are real.

Where is my error, and what is the correct working?

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askedgradient_slope41k388 Nov 2025
8Thank you — the worked example is what makes this usable. – claudia_ferrante 9 months ago
7Related: the same reasoning applies to the counter-ion question. – eighty_six_hours 8 months ago
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This question has not been answered. It has been viewed 3.7k times, which suggests the question is of interest and the answer is not obvious. If you can answer it with a source or a worked calculation, it will be read. See how to ask and answer.
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