tried HPLC for 6 weeks. here is what happened.
purity. That is the whole post, but I will justify it. Everything else people worry about in c/dosinglogs is downstream of it. Titration speed, muscle cramps, the endless dose arguments — most of it resolves if you sort purity out first, and almost nobody does. I say this having got it wrong for 6 months. My…
Water content matters more than people think. If a vial is carrying residual moisture, your "10mg" is not 10mg of peptide.
Slight fix: the number was 99.1, not 93.7. Decimal point, but a fairly consequential one.
Detection wavelength? chromatogram and that changes at different wavelengths.
Injection volume and flow rate? Those affect resolution.
axis labels included, always
The related substances profile is way more interesting than the main peak %. A 98% with 16 peaks is different from a 98% that is one 27% impurity.
Injection volume and flow rate?
Counter-anecdote: opposite result, same dose. Which mostly tells us the variance is huge.
related substances are where the story lives, not the main peak
Ran the same vial on two columns, different purity, both right, different separation. Method matters more than equipment.