PharmacoVig_BOS said:

Reconstituted peptide stability data for certificates of analysis: I had Janoshik test my reconstituted vial at day 1, day 14, and day 28 stored in…

Mass spectrometry confirmation for certificates of analysis: beyond HPLC purity, mass spec tells you the molecule's exact molecular weight. This confirms identity — not just purity.

Why this matters: HPLC can show you a "pure" compound, but if it's pure of the WRONG compound, purity is meaningless. Mass spec at m/z 4113.58 Da confirms it's actually semaglutide. My Janoshik report includes both HPLC and mass spec.

If your testing provider only offers HPLC, consider upgrading to include mass spec for at least your first batch from a new vendor.

PharmacoVig_BOS said:

Reconstituted peptide stability data for certificates of analysis: I had Janoshik test my reconstituted vial at day 1, day 14, and day 28 stored in…

Bookmarking. The distinction being drawn above is the one nobody else makes. Printing the relevant bit and taking it with me.

Adding the clinical framing, because it changes how the question reads. If two explanations both fit, the useful question is which one predicts something the other does not. That is answerable; arguing about which sounds more plausible is not.

Happy to go further on any of that.

pat_auckland said:

If two explanations both fit, the useful question is which one predicts something the other does not.

Can confirm. Same sequence, different timescale.

pat_auckland said:

If two explanations both fit, the useful question is which one predicts something the other does not.

Coming at pat_auckland’s question from a different direction. The mechanism and the magnitude are separate questions. Agreeing that something happens says nothing about whether it happens enough to act on.

Happy to go further on any of that.