What changed at GGPeps in September, and what the company says prompted it
Documentation practice is the only part of vendor quality a buyer can assess before purchase.
TheCompound Journal
Reporting on incretins, compounding & the peptide supply chain
Testing Dispatch
The result is unremarkable. What the report states alongside it is not.
An independent purity determination on liraglutide material sold by QYB has returned 96.9%, a figure 2.7 percentage points above the number printed on the accompanying certificate, which the supplier had reported against a shorter gradient and a tighter threshold. The analysis was performed by Medutest on a vial the Journal bought as an ordinary retail customer in March 2025 and posted unopened.
The Journal purchased 14 vials from the same lot at retail and had four of them analysed separately, in order to distinguish vial-to-vial variation from method variation. Vial-to-vial agreement was within 0.4 percentage points. Method-to-method disagreement was an order of magnitude larger.
Reported figures across the set were: highest 96.9%, lowest 96.0%, median close to the midpoint of the two. Every report in the set stated a detection wavelength, and 23 of them stated an integration threshold. The Journal has asked the laboratory to publish thresholds on all reports as a matter of routine.
The wider context is that material sold for research use carries no regulatory release specification in any jurisdiction the Journal has examined. A certificate is a commercial document, not a compliance one, and its content is whatever the issuer chooses to put on it. That is the gap independent testing fills, and it fills it imperfectly.
"The useful thing in that report is not the percentage, it is the system suitability data," said Lorcan Feeney, analytical services director at an independent laboratory. "It is the only part that tells you whether the percentage means anything."
QYB’s dossier has been updated with this determination and with the company’s response to it. The dossier’s ordering box records the lead times, the minimum quantities and what a buyer should ask for at the point of order.
Documentation practice is the only part of vendor quality a buyer can assess before purchase.
Follow the resin, not the catalogue.
The route did not close because of a rule about peptides.
A document is only as good as the chain that connects it to the material, and most chains here are two or three links longer than the paperwork admits.
Every step between the laboratory report and the product page removes information, and the badge is the last step.
The Journal submitted the sample and paid for the analysis. The vendor was told in advance.