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c/hplc·submitted 10 months ago by u/ewan_zielinski

[Discussion] the chromatogram advice in here is 2 years out of date

Discussionbranch of 6 comments

the chromatogram advice in here is 2 years out of date — a position I have arrived at slowly and would like tested. Numbers, in the order they matter: 2 years. Resolution between two peaks depends on retention, selectivity and efficiency. A shallower gradient buys retention and usually resolution, at the cost of peak…

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6 comments, started 10 months ago
u/clara_danquah-15 points·10 months ago

Carryover from a previous high-concentration injection looks exactly like a small impurity. The blank injection is four minutes and it removes the ambiguity entirely.

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u/ewan_marchand1 point·10 months ago

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

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u/hydration_hank1 point·10 months ago

a blank injection between samples costs four minutes and settles most arguments

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[deleted]1 point·10 months ago

[deleted]

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u/elodie_grimaldi1 point·10 months ago

area percent is relative to what the detector saw and nothing else

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u/arne_nyberg1 point·10 months ago

Carryover from a previous high-concentration injection looks exactly like a small impurity.

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

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