A supplier should be the least uncertain thing in your protocol
Everything below follows from that one commitment.
In 2019 a repeat experiment failed three times before anyone thought to re-test the peptide. It was 87% pure against a certificate claiming 99. The certificate had been written by the seller.
That is the ordinary state of research chemical supply. Analytics are optional, self-reported, and rarely tied to the specific container in front of you. A study can lose a quarter to material that was never what the label said.
Axon inverts the default. Nothing is listed until an independent, ISO-17025 accredited lab has run HPLC purity, mass-spec identity and gravimetric fill weight on that synthesis run. The full report — raw chromatogram included, not a summary — is published against the lot number before a single vial can be bought. If the numbers miss the published floor, the lot does not ship at any price.
We keep a retained sample of every lot for twenty-four months, so a result you got last year can still be checked against the physical material. Roughly one lot in forty fails release. Those are absorbed as cost, which is the only arrangement that keeps the incentive honest.
An ISO-17025 lab we do not own runs every release test. We cannot grade our own work.
The chromatogram and mass-spec trace publish in full, tied to the lot number.
Physical material is held so last year’s result can still be re-checked today.
Off-spec material is never discounted, rebadged or sold into a secondary channel.