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c/hplc·submitted 1 months ago by u/arne_nyberg

genuine question about method development that I am slightly embarrassed to ask

Methodbranch of 7 comments

genuine question about method development that I am slightly embarrassed to ask. Searched first, found three threads that contradict each other, hence the post. Resolution between two peaks depends on retention, selectivity and efficiency. A shallower gradient buys retention and usually resolution, at the cost of…

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7 comments, started 1 months ago
u/cagrilintide_enthusiast134 points·1 months ago

Area percent is the integrated area of your peak over the total integrated area at one wavelength on one gradient. Change any of those and the number changes without the sample changing.

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[removed]94 points·1 months ago

[removed by moderator]

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u/sig_figs_sammod · analytical137 points·1 months ago

Is that baseline drawn by the software or by hand?

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u/bilal_adebayo52 points·1 months ago

Same method at both labs, or two different gradients?

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u/nora_lundgren18 points·1 months ago

Small fix — 214nm, not 210. It matters for the comparison you are making with the other run.

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u/ewan_zielinski29 points·1 months ago

Same view — reporting the gradient is what makes a result checkable rather than merely stated.

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u/fatima_yildiz34 points·1 months ago

Right. And a blank between injections settles the carryover argument before it starts.

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