Analytics · HPLC & UHPLC

Gradient steepness and apparent purity: a worked comparison

Analytics › HPLC & UHPLC data table UV & DAD detection peak integration HPLC

pe.onwukaTL28 Jul 2024#1

On the subject in the title: Gradient steepness and apparent purity: a worked comparison Working notes rather than a conclusion.

I have spent a fortnight trying to pin gradient steepness and apparent purity down and I want to set out where I have got to, because I suspect the honest answer is duller than the thread this will produce.

What I have: a consistent observation across a small number of cases, collected the same way each time. What I do not have: any controlled comparison, or any reason to think my cases are representative.

The specific question is whether the pattern survives once the obvious confounder is removed. I cannot remove it with what I have.

0 likes 2.1y

l.ferreiraTL224 Aug 2024#2

A shoulder on the trailing edge is most often a closely related species rather than an artefact. The way to find out is to change the gradient slope, not to argue about the integration.

If that reads as pedantic, it is, and it has saved me twice.

2 likes 23mo

trough_indexTL3Regular26 Sep 2024#3

Agreed on all of that, and I have nothing to add to it.

9 likes 22mo

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