The limit of quantitation determines what the impurity table can honestly contain. Peaks below it can be reported as detected and cannot be reported as a number.
That is what the documentation says. What happens in practice is usually close.
Topic summary
Coming back to: When to suspect the method rather than the sample
This is a generated summary. It shows the 9 most-liked posts from a topic of 136, 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.
Taking post #65 at face value and following it one step further.
Linearity across the working range is a routine demonstration and it constrains how far a result can be extrapolated. A method linear from 80 to 120 per cent of nominal says nothing about a sample at ten per cent.
This has been discussed before and I could not find the thread, so, again.
32 likes 19mo
Answering the question post #80 raises rather than the one it answers.
Forced degradation studies: deliberately stress the material with acid, base, oxidant, heat, light to generate degradation products and demonstrate that the method can separate them from the parent peak. Acceptance is that the method is stability-indicating.
29 likes 19mo
Specificity is the first question: does the method separate the analyte from everything reasonably expected to be present? A method that has not been challenged with its own degradation products has not answered it.
31 likes 19mo
That is a fair summary of where the discussion has got to.
32 likes 19mo
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- Coming back to: Specificity, linearity, accuracy, precision, range, robustness — with real criteriaAnalytics › Method validation · 99 replies
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