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c/hplc·submitted 7 months ago by u/egfr_watcher

[Meta] the gradient rule is doing its job and people should stop complaining

Correctionbranch of 11 comments

the gradient rule is doing its job and people should stop complaining. Nothing about this affects the ranking maths, before anyone asks. Reading a trace posted here, in the order I actually look at things. Axes first — if the wavelength and the time axis are not labelled, I stop. Then the baseline: where has it been…

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11 comments, started 6 months ago
u/step_count_stan73 points·6 months ago

report the method or do not report the number

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u/gustav_solberg31 points·6 months ago

System suitability — repeat injections, tailing factor, plate count, RSD on area — is what tells you the instrument was fit for the measurement that day. Without it, the purity figure is unanchored.

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u/egfr_watcher15 points·6 months ago

you cannot report to two decimals off that baseline

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u/liv_okafor0 points·6 months ago

report the method or do not report the number

Adding one practical thing — run the blank. It answers this before anyone has to argue about it.

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u/marisol_frisk0 points·6 months ago

a shoulder is not an impurity until you can resolve it

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[deleted]1 point·6 months ago

[deleted]

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u/marisol_frisk1 point·6 months ago

system suitability before you believe any number on the run

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u/alcohol_aversion1 point·6 months ago

reproducibility beats resolution if you only get one of them

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u/gustav_solberg1 point·6 months ago

Sent the same vial to VendorInvestigate and Medutest. 98.1% against a claimed 98.0%. The difference was the gradient, not the material.

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