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Single comment threadYou are looking at one branch of the HPLC thing finally clicked for me and I want to write it down — 24 comments in the full submission. View in context.
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c/hplc·submitted 4 months ago by u/medutest_mel

the HPLC thing finally clicked for me and I want to write it down

Labbranch of 8 comments

Something I noticed reading old threads that I have not seen said out loud. The advice on integration in this community changed substantially around the start of last year, and nobody went back and updated the older posts. So depending on which thread the search engine hands you, you get two contradictory answers…

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8 comments, started 4 months ago
u/kofi_ferreira-22 points·4 months ago

Strongly agree. Largest single impurity tells a different story than total purity.

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u/medutest_melOP1 point·4 months ago

Gradient goblin mode: changed the solvent composition 5 times, finally got good resolution on a chromatogram peak.

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u/careful_gradient1 point·4 months ago

Gradient goblin mode: changed the solvent composition 5 times, finally got good resolution on a chromatogram peak.

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

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u/clara_danquah1 point·4 months ago

two labs, two different baselines, two different purity numbers, both honest

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u/medutest_melOP1 point·4 months ago

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

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u/mateusz_mensah1 point·4 months ago

Water content matters more than people think. If a vial is carrying residual moisture, your "10mg" is not 10mg of peptide.

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u/blunt_coldbox_20241 point·4 months ago

axis labels included, always

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u/coa_janitormod · c/coa1 point·4 months ago·edited

Injection volume and flow rate? Those affect resolution.

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