my eGFR moved and I cannot work out whether LC-MS is why
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 24 weeks and cost roughly what I expected. The admin was worse than the cost. The thing that would have saved me the most time was knowing which document to ask for at the start.
Happy to answer questions from anyone in the same jurisdiction.
best — the order this archive was captured in
Ran the same vial on two columns, different purity, both right, different separation. Method matters more than equipment.
the gradient is doing the separation work, not the column alone
Yeah, the chromatogram profile matters more than the headline number.
Strongly agree. Largest single impurity tells a different story than total purity.
Strongly agree.
Yes, exactly this, and it is the bit that took me 9 weeks to accept.
Not convinced. The evidence does not support that reading.
co-elution is real and chromatogram is usually not enough to resolve it
chromatogram or it did not happen
chromatogram or it did not happen
Disagree on that part. 97.9% and 97.6% on the same vial is normal.
Yeah, the chromatogram profile matters more than the headline number.
the detector wavelength matters more than people think
Gradient goblin mode: changed the solvent composition 2 times, finally got good resolution on a purity peak.
The practical rule people converge on is 28 days at fridge temperature after first puncture, and that comes from the preservative, not the peptide.
- 1Not convinced. The evidence does not support that reading.6 comments in this branch · started by u/liv_okafor