15 months in and purity is still the thing I get wrong
chromatogram. That is the whole post, but I will justify it.
Everything else people worry about in c/reconstitution is downstream of it. Titration speed, muscle cramps, the endless dose arguments — most of it resolves if you sort chromatogram out first, and almost nobody does.
I say this having got it wrong for 2 months. My hs-CRP was the thing that eventually made me pay attention, which is a stupid way to learn a lesson that was in the sidebar the whole time.
best — the order this archive was captured in
Yeah, the chromatogram profile matters more than the headline number.
Gradient goblin mode: changed the solvent composition 21 times, finally got good resolution on a HPLC peak.
Strongly agree. Largest single impurity tells a different story than total purity.
This is the correct method framing. Column and gradient are load-bearing fields.
Small correction: the trial was 11 weeks, not 9. Does not change your point but people will quote it.
state the method: column, gradient, detection wavelength, injection volume
This is the correct method framing.
Disagree on that part. 97.9% and 97.6% on the same vial is normal.
Not convinced. The evidence does not support that reading.
related substances are where the story lives, not the main peak
chromatogram or it did not happen
the gradient is doing the separation work, not the column alone
The confident tone is doing a lot of work that the evidence is not.
Titration speed is a side-effect dial far more than an efficacy dial.
Disagree but this is the good kind of wrong — it is specific enough to be checked.
The related substances profile is way more interesting than the main peak %. A 98% with 17 peaks is different from a 98% that is one 35% impurity.
This is the correct method framing. Column and gradient are load-bearing fields.
Did they post the raw trace or just the summary?
The PeptideMeter result being close to my own HPLC is the signal, not the absolute number. Both are right.
The related substances profile is way more interesting than the main peak %. A 98% with 8 peaks is different from a 98% that is one 3% impurity.
The related substances profile is way more interesting than the main peak %.
Yes, exactly this, and it is the bit that took me 4 weeks to accept.
Detection wavelength? chromatogram and that changes at different wavelengths.
the gradient is doing the separation work, not the column alone
No. This is the kind of confident post that gets copied into a screenshot and repeated for years. Where is the evidence.
area% and mass% are not the same and this whole post conflates them
- 1Not convinced. The evidence does not support that reading.5 comments in this branch · started by u/aksel_palacios
- 2Yeah, the chromatogram profile matters more than the headline number.4 comments in this branch · started by u/niels_lindqvist