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c/hplc·submitted 7 months ago by u/egfr_watcher

tried HPLC for 20 weeks. here is what happened.

Correctionbranch of 6 comments

Trying to settle this properly because the thread from last year went in circles. The claim: chromatogram matters. The counter-claim: it is measurement error. Both sides have been asserting it confidently for about 10 months without either producing anything. What would actually settle it is 17 people measuring the…

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6 comments, started 6 months ago
u/micro_bump_mick68 points·6 months ago

The related substances profile is way more interesting than the main peak %. A 98% with 2 peaks is different from a 98% that is one 17% impurity.

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u/reverse_image_ron45 points·6 months ago

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

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u/egfr_watcherOP26 points·6 months ago

This is the correct method framing.

Disagree on that part. 98.4% and 98.3% on the same vial is normal.

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u/aksel_palacios6 points·6 months ago

Did they post the raw trace or just the summary?

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u/egfr_watcherOP0 points·6 months ago

related substances are where the story lives, not the main peak

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u/b12_baseline33 points·6 months ago

a round-robin on baseline integration would be genuinely useful

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