[Correction] you cannot report area% to two decimals off that baseline
Explainer, as requested in the last thread: you cannot report area% to two decimals off that baseline. Retention time shifted 0.4 minutes and I assumed the worst. It was the column temperature. Gave the same trace to two people I trust and got two integrations about a point apart. That was the most educational…
How old is the column and roughly how many injections has it seen?
214nm sees the peptide bond, 280nm sees the aromatics
What wavelength, and what was the gradient?
Right. And a blank between injections settles the carryover argument before it starts.
Retitled: the original claimed a comparison the post does not actually make.
a shoulder is not an impurity until you can resolve it
Retitled: the original claimed a comparison the post does not actually make.
This is the whole methodological point of the board in one line.
Yes. Retention time is a hypothesis about identity. Mass is the answer.
That is area percent, not mass percent. The trace cannot give you the second one.
reproducibility beats resolution if you only get one of them
a blank injection between samples costs four minutes and settles most arguments