A certificate of analysis (COA) is the document that turns a purity claim into evidence. Once you know what each field means, you can evaluate any supplier’s testing in under a minute. Here is every field you should expect, and what it tells you.
Batch code
The batch (or lot) code ties the certificate to a specific production run. It is the anchor for everything else: a COA that doesn’t name a batch can’t be matched to the vial in your hand. Every product we ship carries a batch code; where a report has been published for that batch, you’ll find it on the lab results page.
Laboratory
Who ran the test? Independent laboratories have no stake in the result. In-house testing isn’t worthless, but it can’t carry the same weight. Look for a named third-party lab.
Date tested
Testing has a shelf life in the sense that it describes the batch at the time of analysis. A recent date on a recently produced batch is what you want.
Measured content
The quantified amount of peptide found in the sample — for example, 10.23 mg in a vial labelled 10 mg. This matters for accurate reconstitution, where your calculations assume a known mass.
Purity
The HPLC purity percentage — the proportion of the sample that is the target peptide by peak area. Higher is better, but always read it next to the identity result.
Methodology
Which techniques were used. A strong report combines HPLC (purity) with mass spectrometry (identity). If only one is present, you only have half the picture.
Verification
The best certificates can be checked at source. Our batch pages publish the laboratory’s public verification key so anyone can confirm the result independently — see, for example, the Tesamorelin batch AS250910 report.
A quick checklist
- Named batch code that matches your vial ✓
- Independent laboratory ✓
- Recent test date ✓
- Both purity and identity methods ✓
- A way to verify the result yourself ✓
Ready to see it in practice? Browse the published reports or explore the catalogue.
