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

VendorInvestigate result on a Zhuhai semaglutide lot lands 1.1 points above the supplier’s stated figure

The result is unremarkable. What the report states alongside it is not.

VendorInvestigate has released a batch of 21 analytical reports on research-grade semaglutide lots, including material from HJ and GGPeps. Reported purities range across roughly 1.1 percentage points, and the report set is unusual in stating the analytical method for every determination rather than for some of them.

Reported figures across the set were: highest 97.3%, lowest 93.3%, median close to the midpoint of the two. Every report in the set stated a detection wavelength, and 21 of them stated an integration threshold. The Journal has asked the laboratory to publish thresholds on all reports as a matter of routine.

Four independent services — VendorInvestigate, Medutest, and the two others operating in this market — carry the analytical burden for a trade that has no release-testing obligation of its own. Each is paid by whoever submits the sample, which is usually the vendor. The Journal’s position is that a submitter-pays model is workable but that its incentive structure has to be stated whenever a result is quoted as verification.

"Content is the number that matters if you are doing arithmetic with a vial, and content is the number nobody sells," said Marek Doležal, analytical chemist and former QC laboratory manager. "Purity is what you can afford. Content is what you need."

HJ’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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