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

[Question] how do you actually verify purity

Questionbranch of 12 comments

Quick one. Canada here. chromatogram works very differently where I live than in the threads that dominate the front page, and I keep seeing people confidently given advice that simply does not apply outside the US. Specifics: the route I used took 17 weeks and cost roughly what I expected. The admin was worse than…

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12 comments, started 1 year ago
u/sig_figs_samMOD694 points·1 year ago

This is an urgent-care question wearing a forum question's clothes. Please contact a clinician rather than waiting for replies.

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u/ewan_zielinski479 points·1 year ago

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

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u/nora_lundgren574 points·1 year ago

That is net peptide content, not purity. Different number, different meaning.

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u/clara_danquah237 points·1 year ago·edited

That is net peptide content, not purity. Different number, different meaning.

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[removed]170 points·1 year ago

[removed by moderator]

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u/ravi_bergstromOP120 points·1 year ago

Gradient goblin mode: changed the solvent composition 14 times, finally got good resolution on a HPLC peak.

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u/ravi_bergstromOP106 points·1 year ago

Gradient goblin mode: changed the solvent composition 18 times, finally got good resolution on a method development peak.

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u/reflux_report83 points·1 year ago·edited

chromatogram or it did not happen

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u/honest_syringe_202569 points·1 year ago

area% and mass% are not the same and this whole post conflates them

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u/week_four_wall819 points·1 year ago

Mechanistically the bit that matters is method development. It explains most of the early profile and a decent chunk of the outcome.

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u/samir_falk595 points·1 year ago·edited

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

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u/bilal_adebayo157 points·1 year ago

area% and mass% are not the same and this whole post conflates them

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