A Certificate of Analysis (COA) is the single most important document attached to any research compound — yet it’s also one of the most misunderstood. A COA is only as trustworthy as the laboratory that issued it and the methods behind it. This article explains what a COA actually proves, and why a supplier’s own COA should never be the end of the story.
What a COA actually contains
A meaningful COA confirms two distinct things about a batch of material: its identity (is the compound what the label says it is?) and its purity (what proportion of the sample is the target compound versus impurities?). A complete COA will typically state the compound name and sequence, the batch or lot number, the analytical methods used, the purity result as a percentage, the date of analysis, and the name of the issuing laboratory.
If any of those fields are missing — particularly the lab name, the method, or the batch number — the document tells you very little.
Supplier-issued vs independent COAs
Most research compounds change hands several times before reaching the end buyer. At each step, a COA may be passed along — often the one originally produced by the manufacturer. The problem is obvious: a manufacturer testing its own product has a clear conflict of interest, and there is no guarantee the certificate even matches the batch you receive.
An independent COA removes that conflict. The material is sent to a separate, accredited laboratory that has no stake in the result. The lab issues the certificate directly, tied to the specific batch tested. That is the difference between “we’re told it’s 99% pure” and “an independent lab measured this batch at 99% pure.”
What to look for
- The certificate names the issuing laboratory — not just “tested in-house”
- The batch or lot number on the COA matches the vial you received
- Both identity (e.g. mass spectrometry) and purity (e.g. HPLC) are reported
- The date of analysis is recent and present
Our approach
At VeridianLabs, every batch is sent to an independent UKAS-accredited laboratory before it enters our inventory. The COA is issued by that laboratory directly and published against the relevant product listing. We never rely on supplier-issued certificates alone.
All compounds supplied by VeridianLabs are for research use only. This article is provided for informational purposes and does not constitute medical advice or any health claim.