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c/hplc·submitted 1 year ago by u/honest_syringe_pls

unpopular opinion: most of what gets said here about integration is guesswork

Correctionbranch of 8 comments

unpopular opinion: most of what gets said here about integration is guesswork. Not a hot take, just something I have not seen said plainly here. Chased a ghost peak for three weeks. It was the plumbing. It is always the plumbing. A shoulder that does not baseline-resolve cannot be quantified honestly. You can report…

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This branch

8 comments, started 1 year ago
u/valeria_cardoso-28 points·1 year ago

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 unanchored.

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[removed]1 point·1 year ago

[removed by moderator]

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u/sig_figs_sammod · analytical1 point·1 year ago

ghost peak, check the plumbing first, it is always the plumbing

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u/gustav_solberg1 point·1 year ago

What did system suitability look like on that sequence?

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u/two_mil_or_one1 point·1 year 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/cormac_roos1 point·1 year ago

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

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u/liv_okafor1 point·1 year 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/nabila_espinoza1 point·1 year ago

Cosigning the wavelength point. Half the disagreements in this board are two people looking at different detectors.

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