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c/hplc·submitted 2 years ago by u/ahmed_rasmussen

[Discussion] can we stop arguing about HPLC until somebody posts a number

Discussionbranch of 7 comments

can we stop arguing about HPLC until somebody posts a number. I am not trying to be the "source?" guy. I would just like a source. 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…

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7 comments, started 2 years ago
u/fatima_yildiz82 points·2 years ago

What wavelength, and what was the gradient?

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u/hplc_hobbyistMOD45 points·2 years ago

Trace posted without axis labels — asked for a relabelled version rather than removing it.

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u/ahmed_rasmussenOP0 points·2 years ago

Can you post the trace with the axes labelled?

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u/ferran_krastev49 points·2 years ago

Ran a blank after a high-concentration injection and found the carryover I had been calling an impurity.

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u/teodor_szabo16 points·2 years ago

integration decisions move the number more than the sample does

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u/elodie_grimaldi8 points·2 years ago·edited

integration decisions move the number more than the sample does

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

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u/hugo_bergstrom34 points·2 years 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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