Peptide COA library

Our reports come from Janoshik Analytical, an independent laboratory: Retatrutide in all three sizes (10, 20, 30 mg) and GHK-Cu 100 mg, each one verifiable at the lab with its task number and key.

Latest test · 15 Sept

99.603%

GHK-Cu · 100 mg · purity (HPLC)

Janoshik Analytical · #217016 · Lot PC260705C100

Verify on Janoshik

Average purity of our published reports

99.60%

across 4 reports

4 certificates published

Published reports

Most recent first. Each one can be checked at Janoshik with its task number and key.

How a report is made

A vial of the size is sent to the laboratory. Two measurements answer two different questions.

Reverse-phase HPLC: how clean
The sample is separated on a column and read by UV at 214 nm, the wavelength of the peptide bond. Purity is the area of the main peak against every peak on the trace.
Identity: which molecule
The laboratory identifies the compound in the sample and names it in the results (for retatrutide, a blind test against semaglutide, tirzepatide and retatrutide), next to the quantity measured in mg.
What goes on the certificate
The laboratory name, a task number and a key that can be looked up at the laboratory itself, the size tested and the date.

Field by field, a certificate is read in How to read a peptide COA · How to read a Janoshik test report · Testing questions (FAQ) · Buy retatrutide in Europe

Frequently asked questions

How to verify a Janoshik report?

Open verify.janoshik.com, enter the task number and the key printed on the report, and compare the result with the PDF: same lot, same purity, same date.

Questions about a certificate: support@oxpeptides.com