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c/hplc·submitted 5 months ago by u/ewan_tulloch

[Question] is 98.6% actually fine or am I being sold a rounding error

Questionbranch of 8 comments

Filing this under things worth writing down: is 98.6% actually fine or am I being sold a rounding error. Pulling the figures out of the title: 98.6%. All of it is written down as it happened rather than reconstructed. Mass spectrometry answers identity. UV purity answers relative quantity under the run conditions. A…

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8 comments, started 5 months ago
u/clara_danquah11 points·5 months ago

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

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u/zeynep_zielinski5 points·5 months ago

That figure cannot be quoted to two decimals off that baseline. The precision is not in the data.

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u/cagrilintide_enthusiast2 points·5 months ago

This. A shoulder that does not baseline-resolve is a question, not a quantity.

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[deleted]5 points·5 months ago

[deleted]

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u/valeria_cardoso6 points·5 months ago

Push back: a longer run is not automatically better resolution. You are trading peak width for time and the ratio is what matters.

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u/careful_gradient4 points·5 months ago

Did you run a blank between injections?

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u/valeria_cardoso2 points·5 months ago

Yes. Retention time is a hypothesis about identity. Mass is the answer.

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u/erez_yilmaz2 points·5 months ago

baseline choice is a decision, not a measurement

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