net peptide content vs purity — two different numbers, same vial, and only one is on your COA
Following on from the area% thread, because the same confusion turns up in a second form.
People read a 10mg vial at 99% purity and conclude they have 9.9mg of peptide. They do not. Purity is a ratio between chromatographic species; it says nothing about total mass. Net peptide content is a separate assay and it appears on a minority of certificates.
The practical size of the gap is usually somewhere between five and twelve percent once you account for water and counterion. It is not a scandal and it is not hidden — it is simply a different measurement that most documents do not include.
Does anyone actually get net content routinely? I have it on maybe one in six documents.
best — the order this archive was captured in
One in eight across my folder, and it clusters hard by vendor. WXT and BCH have it most of the time. Everyone else, rarely, and usually only when somebody asked.
Which tells you the assay is not hard or expensive — it tells you it is not demanded. If a hundred people asked for it on every order it would be on every document inside a year.
that is a much more actionable read than mine. it is a demand problem, not a capability problem.
then ask. every order. it costs one sentence in an email and the aggregate effect over a community this size is not nothing.
same argument for water content and it worked on at least one vendor already.
and packaging. ERP went from foam and optimism to a proper cold box after about a year of members saying so in public.
the collective-nagging mechanism is genuinely the most effective tool this community has and it never gets written up as one.
amino acid analysis is the assay that gets you net content properly and it is the boring test that catches the interesting frauds. nobody orders it.
it also confirms composition, which UV cannot. two answers for one price and it is still the least-requested thing on any menu.
Adding this to the c/coa wiki alongside the area% explainer. The two together answer most of what arrives in the modqueue as "is this good".
so a 10mg vial might have nine milligrams of peptide and everyone involved has been honest. edit: yes, per the table in the other thread. this is the least satisfying accurate answer i have received.
if the gap is predictable it does not matter. everyone is dosing off label weight and it works.
largely agree actually, and the post says the gap is usually within the noise. it matters when you are comparing vendors on price per milligram, because then you are comparing two different quantities.
- 1One in eight across my folder, and it clusters hard by vendor. WXT and BCH…6 comments in this branch · started by u/coa_collector