Certificate of Analysis
A Certificate of Analysis, or COA, is a lab report for one specific batch of a product. It lists the tests that were run on that batch and the results they gave.
Where the word comes from
Certificate comes from the Latin certificare, “to make certain,” built from certus (“sure”) and facere (“to make”). Analysis is Greek: análysis, “a loosening apart,” from ana- (“up”) and lyein (“to loosen”) — taking something apart to see what it is made of. So the phrase means, quite literally, a document that makes the take-apart results certain. Issuing a signed test report for each manufactured batch became standard practice with the quality-control systems of the 1900s.
What it means here
A COA typically confirms two things: identity — the material really is the named compound — and purity, the percent of the material that is that compound. Some COAs also report extra checks, such as an endotoxin test. Every COA is tied to a lot number, the code printed on the vial. Matching the lot number on a vial to the lot number on its COA is how a researcher confirms the report describes the exact batch in hand, not the product in general. A supplier document without a lot number, test method, and date is not a real COA.
Words you’ll see together
- lot number — the batch code that ties the report to one production run
- specification — the limit each result is checked against (“spec”)
- test method — the named procedure behind each result, such as HPLC
- identity — the line confirming the material is the named compound
- batch — one production run; a COA covers exactly one
- date of analysis — when the tests were actually run
Related terms
- Purity — the headline number on most COAs
- HPLC — the separation method behind the purity result
- Lot number — the code that ties a COA to one specific batch
- Endotoxin — an additional test some COAs report
Where it appears in our catalog
- Certificates of Analysis FAQ — how COAs work for our batches
- Reading a Certificate of Analysis — a line-by-line guide to the document
- Choosing a supplier — why a checkable COA is a core supplier test
References
- Artemis Labs, Certificates of Analysis FAQ
- Artemis Labs, Reading a Certificate of Analysis
