How to Read a Certificate of Analysis
VQ Health Editorial · 13 Sept 2026 · 6 min read
How to Read a Certificate of Analysis
A Certificate of Analysis (COA) is the primary quality document for a batch of research material. Understanding its structure helps laboratories verify that the material received matches the documentation.
The header block
Every legitimate COA identifies the product, the batch or lot number, the testing laboratory and the test date. The batch number is the critical link: a COA is only meaningful for the exact batch printed on it. When you receive material from VQ Health, the batch on the vial should match the batch on the COA in our library.
Identity tests
Identity testing confirms the material is the compound it claims to be. Mass spectrometry compares the measured molecular mass against the theoretical mass of the compound. A match supports identity; it does not by itself measure purity.
Purity assays
HPLC (high-performance liquid chromatography) separates the components of a sample and reports the main peak as a percentage of total signal. The chromatogram — not just the headline number — shows whether minor peaks are present.
What a COA cannot tell you
A COA describes one batch at one point in time. It does not transfer between batches, and it is not evidence of any effect in any biological system. Research materials remain research materials regardless of documented purity.