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c/hplc·submitted 7 days ago by u/clara_danquah

peak at 4.2 min, nobody can tell me what it is, ideas

Methodbranch of 8 comments

chromatogram. That is the whole post, but I will justify it. Everything else people worry about in c/dosinglogs is downstream of it. Titration speed, muscle cramps, the endless dose arguments — most of it resolves if you sort chromatogram out first, and almost nobody does. I say this having got it wrong for 21…

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8 comments, started 6 days ago
u/first_hundred96 points·6 days ago

instrument quality is less important than analyst consistency

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u/clara_danquahOP66 points·5 days ago

instrument quality is less important than analyst consistency

Counter-anecdote: opposite result, same dose. Which mostly tells us the variance is huge.

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u/joaquin_petrov82 points·5 days ago

the gradient is doing the separation work, not the column alone

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u/cagrilintide_enthusiast62 points·5 days ago

Ran the same vial on two columns, different purity, both right, different separation. Method matters more than equipment.

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u/clara_danquahOP39 points·5 days ago

a round-robin on baseline integration would be genuinely useful

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[deleted]27 points·5 days ago

[deleted]

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u/runa_cabrera40 points·5 days ago

This is the "correlation is mechanism" thing again. You changed three variables at once.

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u/enzo_petrescu9 points·5 days ago

the gradient is doing the separation work, not the column alone

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