Third-Party vs In-House Testing: Reading Analytical Claims
“Third-party tested” appears on most peptide supplier sites. It is a meaningful claim only if you know who tested what, and when.
The two arrangements
In-house testing means the supplier or its manufacturer ran the analysis. This is not inherently unreliable — many manufacturers have capable analytical laboratories — but the party reporting the result has a commercial interest in it.
Third-party testing means an independent laboratory ran the analysis. The value is the independence, and that value only exists if the independent laboratory is actually identified.
Questions that separate the two
Four questions do most of the work.
Which laboratory? A certificate that names the testing laboratory can be checked. One that says “third-party tested” without naming anyone cannot.
Which methods? Identity and purity are separate questions answered by different techniques. A certificate should state which were applied — and it is entirely legitimate for a certificate to say that mass spectrometry was applied where applicable rather than universally, provided it says so.
How is the vial tied to the certificate? This is the question most often skipped. A published certificate is only useful if you can establish that it describes the material you received.
How ours works
Our certificates are published on this website rather than shipped in the box, and they report third-party testing by HPLC and/or mass spectrometry where applicable, stating which methods were applied to a given batch.
Vials are matched to their certificate by cap and crimp colour, checked against the photographs shown on the certificate — the vials do not carry printed batch numbers. That is the mechanism, and it is worth carrying out on arrival rather than at the point of use; see checking a shipment on arrival.
What a claim cannot tell you
No certificate, however independent, tells you about endotoxin, sterility or residual solvents unless those tests were specifically run — see endotoxin, sterility and the limits of research grade. And a purity percentage remains method-dependent: two laboratories can report different figures for the same material without either being wrong.
ExoLabz supplies compounds for laboratory research use only. Nothing on this page is medical advice or a suggestion of human or veterinary use. Certificates of analysis are published on this site.
