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c/hplc·submitted 2 months ago by u/nabila_espinoza

[PSA] chromatogram is not what most of this community thinks it is

Questionbranch of 6 comments

chromatogram is not what most of this community thinks it is. Two minutes of reading now saves an argument later. Started reporting my own integrations with the baseline choice stated. Arguments in my threads dropped by about half. Reading a trace posted here, in the order I actually look at things. Axes first — if…

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6 comments, started 2 months ago
u/peak_area_peteMOD55 points·2 months ago

Trace posted without axis labels — asked for a relabelled version rather than removing it.

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u/andres_restrepo21 points·2 months ago

Disagree. Inter-lab spread of a point or two on this assay is ordinary and calling it a discrepancy misleads people.

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u/rania_okonkwo41 points·2 months ago

Resolution between two peaks depends on retention, selectivity and efficiency. A shallower gradient buys retention and usually resolution, at the cost of peak width and run time.

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u/gustav_solberg17 points·2 months ago

retention time alone is not identity

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u/liv_okafor38 points·2 months ago

Did you run a blank between injections?

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u/nabila_espinoza44 points·2 months ago

214nm sees the peptide bond, 280nm sees the aromatics

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