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c/hplc·submitted 9 months ago by u/mariam_cabrera

does gradient actually matter or is it forum lore at this point

Discussionbranch of 7 comments

Trying to get a straight answer on this: does gradient actually matter or is it forum lore at this point. A shoulder that does not baseline-resolve cannot be quantified honestly. You can report it as an unresolved shoulder, which is useful information, or you can develop the method until it resolves. System…

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7 comments, started 9 months ago
u/peak_area_peteanalytical91 points·9 months ago

you cannot report to two decimals off that baseline

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u/mariam_cabreraOP38 points·9 months ago

Same method at both labs, or two different gradients?

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u/zeynep_zielinski13 points·9 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/egfr_watcher9 points·9 months ago

Disagree.

zeynep_zielinski is right — the integration choice is a decision and it should be stated alongside the result.

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u/blunt_coldbox_202413 points·9 months ago·edited

report the method or do not report the number

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u/bilal_adebayo3 points·9 months ago

Yes — system suitability first. Without it the number is an assertion about the instrument, not the sample.

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u/quiet_reader_994 points·9 months ago

Mass spectrometry answers identity. UV purity answers relative quantity under the run conditions. A document with one and not the other is answering half the question, and the half it answers should be stated.

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