is 96.8% area% actually fine or am i being sold a rounding error
CPC semaglutide 10mg. COA says 96.8%, method line says "HPLC", batch and date both present. Nothing cropped, whole page.
Everyone in here talks about 98 and 99 like they are the floor, and 96.8 feels like it should bother me, but I genuinely cannot tell whether 1.5 points is a real difference or a decimal I should ignore.
What is the honest answer?
best — the order this archive was captured in
The honest answer is "it depends what the 3.2% is", and the COA you are holding does not tell you.
96.8% area means the main peak is 96.8% of what the detector saw. The other 3.2% is something, and the question that matters is whether it is a related substance you would expect — a des-amido form, an oxidation product, a truncation — or something that has no business being there.
A proper document lists related substances individually. Yours says "HPLC" and gives you one number, which is a technique and a total rather than a method and a breakdown. That is the actual problem here, not the 96.8.
oh. so the number is not the issue, the missing breakdown is the issue.
correct. 96.8 with a listed impurity profile is a document. 96.8 with nothing is a claim.
and 96.8 would pass plenty of legitimate specifications. compendial limits for related substances are not 0.5% across the board — people in here have anchored on a number that came from marketing copy rather than from any standard.
this thread has already been worth more than the last twenty i read
Which is why we make people post the whole page. Half the value of this community is in the fields people crop out.
if there is a chromatogram attached, post that too. the shape of the 3.2% tells you more than the size of it.
practical answer: send it. one vial, one service, and you will know whether the 96.8 holds. CPC has come back 98.3 and 98.6 in the community log so a 96.8 claim would actually be conservative for them, which is its own mild signal.
doing that. edit: sent to Janoshik, will post in c/labresults either way even if it makes me look silly.
"either way" is the correct commitment and most people do not make it. good.
also worth asking: is 96.8 the purity or the net peptide content? two different numbers, and a document this thin might be quoting either.
anything under 98 is a scam, bin it
this is exactly the folklore the post is trying to escape. where does 98 come from. name the standard.
i cannot, it is just what everyone says
honestly, respect for saying that instead of doubling down. that is how the folklore actually dies.
Flair changed to Question, which is what this is. Leaving everything else — this is a textbook version of the post this community exists for.
- 1The honest answer is "it depends what the 3.2% is", and the COA you are…7 comments in this branch · started by u/purity_pedant
- 2anything under 98 is a scam, bin it4 comments in this branch · started by u/downvote_magnet