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

[Question] Ireland — has anyone got a straight answer on method development

Questionbranch of 7 comments

gradient. That is the whole post, but I will justify it. Everything else people worry about in c/reconstitution is downstream of it. Titration speed, reflux, the endless dose arguments — most of it resolves if you sort gradient out first, and almost nobody does. I say this having got it wrong for 6 months. My fasting…

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7 comments, started 1 year ago
u/ewan_marchand218 points·1 year ago

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

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u/nora_lundgrenOP80 points·1 year ago

The related substances profile is way more interesting than the main peak %. A 98% with 21 peaks is different from a 98% that is one 37% impurity.

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u/nora_lundgrenOP-18 points·1 year ago

The related substances profile is way more interesting than the main peak %.

Disagree on that part. 99.2% and 99.3% on the same vial is normal.

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u/egfr_watcher1 point·1 year ago

Detection wavelength? LC-MS and that changes at different wavelengths.

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u/rania_okonkwo75 points·1 year ago

state the method: column, gradient, detection wavelength, injection volume

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[deleted]34 points·1 year ago

[deleted]

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u/peak_area_peteMOD164 points·1 year ago

Tracking number removed. It identifies both ends of a shipment.

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