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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 9 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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9 comments, started 5 days ago
u/cormac_roos58 points·5 days ago

Dead space in the needle hub holds a small but non-trivial volume. On low-volume draws that can be several units.

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u/step_count_stan13 points·5 days ago

This is the correct method framing. Column and gradient are load-bearing fields.

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u/peak_area_peteanalytical3 points·5 days ago

Injection volume and flow rate? Those affect resolution.

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u/elodie_grimaldi6 points·5 days ago

Yeah, the chromatogram profile matters more than the headline number.

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u/adaeze_batista3 points·5 days ago

chromatogram or it did not happen

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u/reverse_image_ron43 points·5 days ago

instrument quality is less important than analyst consistency

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u/nora_lundgren32 points·5 days ago·edited

integration decision on a shoulder changes your number by half a point on its own

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u/mateusz_mensah-34 points·4 days ago

Did they post the raw trace or just the summary?

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u/mariam_cabrera1 point·4 days ago

Did they post the raw trace or just the summary?

Yes, exactly this, and it is the bit that took me 93 weeks to accept.

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