Holograms, QR codes and other things that are not verification
Reported from the analysis, not from a warning notice.
Testing Dispatch
PeptideMeter result on a Hong Kong mazdutide lot lands 1.4 points below the supplier’s figure
The Journal submitted the sample and paid for the analysis. The vendor was told in advance.
An independent purity determination on mazdutide material sold by SWB has returned 96.1%, a figure 1.4 percentage points below the number printed on the accompanying certificate. The analysis was performed by PeptideMeter on a vial the Journal bought as an ordinary retail customer in June 2025 and posted unopened.
Content by elemental nitrogen determination returned 98% of the labelled nominal mass, which on a 10 mg vial corresponds to roughly 4.01 mg of peptide rather than the labelled figure. The remainder is accounted for by counter-ion, residual water and residual solvent, none of which is visible chromatographically.
Content by elemental nitrogen determination returned 98% of the labelled nominal mass, which on a 10 mg vial corresponds to roughly 4.01 mg of peptide rather than the labelled figure. The remainder is accounted for by counter-ion, residual water and residual solvent, none of which is visible chromatographically.
Purity became this trade’s single figure of merit because it is the cheapest measurement to obtain and the easiest to compare. Peptide content, which determines how much drug is actually in a vial, costs several times as much and is not offered as a standard release test by any of the twenty companies in the Journal’s dossier programme. Sterility and endotoxin are separate disciplines again, and are neither tested nor claimed.
Rowena Ashcombe, community pharmacist and diabetes educator, was more cautious. "One lot tells you about one lot. I would not draw a conclusion about a company from a single determination, and I would not let a company draw one either."
SWB’s dossier has been updated with this determination and with the date of the request for comment. The dossier’s "what we could not verify" box records the questions still outstanding.
Related coverage
Independent analysis puts a ERP survodutide lot at 95.6%, against 92.3% on the certificate
A reminder that a purity figure is the output of a method, and that methods differ.
What a 23% rise in coupling-reagent prices does to a 2 mg vial
Follow the resin, not the catalogue.
Why summer is a documented quality problem in this trade
The route did not close because of a rule about peptides.
Deamidation is the commonest degradation route and the hardest to see
An isoaspartate rearrangement changes the molecule and not the mass. A method that confirms identity by molecular weight alone will report it as the parent compound.
We split six vials four ways and posted them
The Journal submitted split samples from single lots to three assay services, under names unconnected to this publication, and published each method alongside each result.