Sourcing
Peptide Testing Labs: How to Check That the Lab on a COA Is Real
Our COA primer says to look for a named testing lab. This is the next step: working out whether that lab exists, whether it is qualified to run the test, and whether the report in front of you could plausibly have come from it.
1. Start with a name you can search
"Independent third-party lab" is a claim, not a name. A usable COA gives the laboratory's legal name, a street address, and a way to contact it. Search for the lab on its own website and confirm it actually offers the analytical services listed (peptide HPLC and mass spectrometry are not offered by every contract lab).
2. Understand what accreditation does and doesn't mean
The standard that matters for a testing lab is ISO/IEC 17025, which covers technical competence and the validity of results. Labs are accredited by independent accreditation bodies, and each accreditation comes with a scope listing the specific tests and methods covered.
Several badges sound similar and mean something different:
- ISO 9001 certifies a quality-management system. It does not say the lab's test results are technically valid.
- "FDA-registered facility" means the site has registered with the FDA. Registration is not an approval or endorsement of the facility's testing.
- "GMP" or "cGMP" describes manufacturing practice. Anyone can put the term on a website; look for an actual audit or certificate behind it.
If a lab claims ISO/IEC 17025 accreditation, look it up in the accreditation body's public directory rather than trusting a logo on the report. Check that the certificate is current and that the scope includes the type of analysis (chromatography, mass spectrometry) rather than only unrelated tests.
3. Check the report for internal consistency
Even a real lab's name can be copied onto a document it never produced. Look for details that should agree with each other:
- A report or sample ID that appears on every page and on the chromatogram.
- An analysis date that falls after the production date and before the sale.
- Method details: instrument type, column, detection wavelength, mobile phase. Real reports usually carry them.
- A chromatogram with labeled axes, a retention time for the main peak, and integration results that match the purity stated in the table.
- For identity, an observed mass next to the theoretical mass, with agreement within what the instrument can resolve.
- A signature or reviewer and a date.
4. Ask the lab to confirm
Many laboratories will confirm that a report number exists and matches the sample when asked, though privacy rules or client agreements sometimes mean the request has to go through the company that ordered the test. A supplier who is confident in its documentation should be willing to ask on your behalf.
5. Know what independence does and doesn't cover
A supplier typically commissions its own tests and chooses what to submit. "Third party" tells you the lab is a separate company; it doesn't tell you who selected the sample, whether it was drawn from the finished vial or from a bulk batch, or how many batches were tested before one was published. Reasonable questions: was the tested sample taken from the lot that was sold, and is every lot tested or just a representative one?
Related reading
- Peptide COA Red Flags: Ten Things to Check
- What to Actually Check Before Trusting a Vendor's COA
- Lot Numbers and Traceability
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