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c/hplc·submitted 3 months ago by u/teodor_szabo

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

Discussionbranch of 6 comments

can we stop arguing about method development 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…

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6 comments, started 3 months ago
u/joaquin_petrov276 points·3 months 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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u/teodor_szaboOP177 points·3 months ago·edited

baseline choice is a decision, not a measurement

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u/elodie_grimaldi127 points·3 months ago

Is that baseline drawn by the software or by hand?

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u/careful_gradient256 points·3 months ago

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

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u/amara_haddad150 points·3 months ago

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

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

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u/sofia_petrescu119 points·3 months ago

Careful — you are treating retention time as identity. Two things can co-elute and the trace will not tell you.

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