Analytics · HPLC & UHPLC

Theoretical plates: useful number or ritual?

Analytics › HPLC & UHPLC system suitability data table HPLC UV & DAD detection gradient method

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Solved by a.vestergaard in post #3

On the opening post — agreed on the reasoning, with one qualification. A chromatogram image at a resolution where you can see peak shape but not baseline detail is worth having and is not the same as the data. Ask for the integration table if the number matters.

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mira.patelTL4 Admin11 Jul 2025#1

Theoretical plates: useful number or ritual? I have a specific reason for asking rather than idle curiosity, and the context is below.

Asking about theoretical plates directly, because I have read four threads on it and each answered a slightly different question.

The version I want answered is the narrow one: given the method stated below, is the result within what anyone else has seen? I am not asking what it means yet.

Method, numbers and the two assumptions I am aware of making are below. If the assumptions are wrong that is more useful to me than agreement.

31 likes 13mo

aliquot_lineTL3Regular4 Sep 2025#2

Change the wavelength and the proportions change even though the sample has not. That is the reason the wavelength has to be on the document for the number to mean anything.

Worth one more sentence than it usually gets.

6 likes 11mo

a.vestergaardTL2 Solution13 Oct 2025#3

On the opening post — agreed on the reasoning, with one qualification.

A chromatogram image at a resolution where you can see peak shape but not baseline detail is worth having and is not the same as the data. Ask for the integration table if the number matters.

7 likes 9mo

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