regulatory is the most under-discussed thing on this board
regulatory is the most under-discussed thing on this board. Change my mind, genuinely — I have no stake in being right about this. The three questions, kept separate, because this board runs them together constantly. Identity : is this the sequence I ordered? Answered by mass spectrometry against a theoretical mass.…
Left up. It distinguishes rodent work from human work, which is the standard on this board.
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That is a purity figure, not an identity confirmation. Two different tests and only one answers the question asked.
Correcting myself: I said the regulatory position had not changed and in that jurisdiction it has.
Yes. Nothing here is approved for human use and that should be the first line of every thread, not the last.
Correction: that study was in rodents. Worth stating explicitly since the thread has been reading it as clinical.
the human evidence is thin and the rodent evidence is not
identity testing matters more here than purity does
Purity by area percent tells you the sample is homogeneous. Mass spectrometry tells you what the homogeneous thing is. For a short peptide, the second question is the one worth paying for.
Reconstituted or powder, and how long has it been in solution?
Reconstituted or powder, and how long has it been in solution?
This is the point that should be at the top of every thread here. Identity first.
stability in solution is the practical question nobody asks
ask for the mass spectrum, not just the purity number
read the actual papers, they are more modest than the summaries
identity, quantity, stability — three separate questions
Small fix — fifteen residues, not seventeen. The sequence is public and easy to check.
Sent a vial to Janoshik: 98.2% against a claimed 98.0%, with the mass confirming the sequence. Both halves mattered to me.
Ask for the theoretical mass alongside the measured one. It is a one-line addition to a certificate and it converts a purity claim into an identity claim.
Left up.
Adding the standing caveat — research material is not approved for human use, wherever you are.