which fields turn a COA from a specification into a result
which fields turn a COA from a specification into a result. Change my mind, genuinely — I have no stake in being right about this.
Water content 3.8%, acetate 6.2%, purity 99%, net peptide about 90% of label weight. All four numbers honest, and I had to read it twice.
Spent four months confusing area% and mass% in every post I made here. One explainer thread and it clicked permanently.
Sent one vial to VendorInvestigate and Janoshik. 98.9% and a claimed 98.0%. Cost me more than the vial and I would do it again.
If two or three other people have done the same thing we might actually learn something. Alone it is an anecdote.
best — the order this archive was captured in
UV at 214nm sees the peptide bond and picks up almost everything; at 280nm you are looking at aromatics only. Which wavelength the number came from is part of the number.
Left up and flaired Explainer. This is the answer we keep linking, written properly.
Net peptide content is the fraction of the powder that is actually peptide once counterion, water and residual solvent are accounted for. A 99% pure acetate salt can still be about 85% peptide by mass.
Does the lot on the vial match the lot on the page?
redact your own name, never the batch details
Does the lot on the vial match the lot on the page?
This is the sentence to take away. The rest of the thread is footnotes to it.
Started keeping a folder of every certificate I have been sent. The ones that itemise impurities are a small group and they are mostly the same suppliers.
Careful — "the metadata looks odd" is a reason to ask a question, not a conclusion. Re-issues are ordinary.
- 1Net peptide content is the fraction of the powder that is actually peptide…6 comments in this branch · started by u/stablecoin_steve