net peptide is gross mass minus water minus counterion. that is why 11.4mg of powder can be a correct 10mg vial
#coa-reading 2025-09-30
Tuesday11 messages5 participantstimes are UTC
Highlights from this day
- underfill_uma — net peptide is gross mass minus water minus counterion. that is why 11.4mg of powder can be a correct 10mg vial 18:21
- ghent_gradient — genuine question update from 7 months ago: started asking every supplier for water content and about half now include it 19:02
- ghent_gradient — a supplier certificate on its own is a starting point, not evidence. that is the whole reason the verification channel exists, take that with a pinch of salt the… 19:04
- underfill_uma — follow up purity is what fraction of the contents is the target. assay is how many mg are actually there. different questions 19:09
retention time shifts between runs are normal. relative retention time is the number to compare
genuine question update from 7 months ago: started asking every supplier for water content and about half now include it
a supplier certificate on its own is a starting point, not evidence. that is the whole reason the verification channel exists, take that with a pinch of salt
the three way match is vial, certificate, invoice. if all three agree you have something
no lot no certificate
follow up purity is what fraction of the contents is the target. assay is how many mg are actually there. different questions
[edited]two certificates from the same supplier have an identical chromatogram, is that normal
is there a standard layout or does every lab do their own
an identical chromatogram on two different lots is the single biggest tell there is
does anyone actually check the residual solvents section
sorry to jump in the font on this one changes halfway down, am i being paranoid