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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 6 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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6 comments, started 5 months ago
u/elodie_grimaldi32 points·5 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/hplc_hobbyistruns their own column-22 points·5 months ago

a shoulder is not an impurity until you can resolve it

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u/ewan_tullochOP1 point·5 months ago

Correcting myself upthread: I said the gradient was linear and looking again it has a hold in the middle.

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u/mateusz_mensah1 point·5 months ago

Correcting myself upthread: I said the gradient was linear and looking again it has a hold in the middle.

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

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u/alcohol_aversion1 point·5 months ago

Started reporting my own integrations with the baseline choice stated. Arguments in my threads dropped by about half.

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u/ewan_tullochOP15 points·5 months ago

Same method at both labs, or two different gradients?

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