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

[Discussion] we are measuring integration at the wrong time and calling it noise

Discussionbranch of 7 comments

Posting this because I searched for it and got nothing useful. Setup: 7.5mg, week 51, constipation present but not ruining anything. I changed exactly one variable — LC-MS — and tracked it for 14 weeks. Result: a difference, but a small one, and well inside what I would call noise if someone else posted it. So I am…

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7 comments, started 1 year ago
u/clara_danquah23 points·1 year ago

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

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u/dead_space_doug15 points·1 year ago

the gradient is doing the separation work, not the column alone

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u/quiet_reader_999 points·1 year ago

Small correction: the trial was 20 weeks, not 38. Does not change your point but people will quote it.

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u/cormac_roos3 points·1 year ago·edited

Small correction: the trial was 20 weeks, not 38.

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

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u/joaquin_petrov3 points·1 year ago

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

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u/fatima_yildiz6 points·1 year ago·edited

a round-robin on baseline integration would be genuinely useful

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u/chain_confirm_cpayments1 point·1 year ago

a round-robin on baseline integration would be genuinely useful

Yes, exactly this, and it is the bit that took me 77 weeks to accept.

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