Vol. 3, No. 6 — June 2026Independent since 2024

TheCompound Journal

Reporting on incretins, compounding & the peptide supply chain

A monthly journal of record.
30 issues · 32 contributors
Not medical advice. We sell nothing.

Testing Dispatch

Medutest result on a Wuhan mazdutide lot lands 3.6 points above the supplier’s stated figure

The Journal submitted the sample and paid for the analysis. The vendor was told in advance.

Medutest has published a purity determination of 98.6% on a 10 mg vial of mazdutide supplied by WWB, against a figure of 95.7% on the certificate that accompanied the vial. The sample was submitted by the Journal in July 2024 as part of a continuing programme of arm’s-length purchasing, and the vendor was told before the order was placed that any result would be published.

Reported figures across the set were: highest 98.6%, lowest 95.7%, median close to the midpoint of the two. Every report in the set stated a detection wavelength, and 12 of them stated an integration threshold. The Journal has asked the laboratory to publish thresholds on all reports as a matter of routine.

Reported figures across the set were: highest 98.6%, lowest 95.7%, median close to the midpoint of the two. Every report in the set stated a detection wavelength, and 12 of them stated an integration threshold. The Journal has asked the laboratory to publish thresholds on all reports as a matter of routine.

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 quoted as a priced addition by most of the twenty companies in the Journal’s dossier programme rather than carried as a standard release test. Sterility and endotoxin are separate disciplines again, and are neither tested nor claimed.

"The useful thing in that report is not the percentage, it is the system suitability data," said Marek Doležal, analytical chemist and former QC laboratory manager. "It is the only part that tells you whether the percentage means anything."

WWB’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.

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