Understanding research certificates

What is a Certificate of Analysis?

A Certificate of Analysis, commonly shortened to CoA, is a laboratory document reporting results for a specific sample or batch. It should help connect the tested material to a batch or lot identifier and describe the tests, results and acceptance criteria used by the laboratory.

A CoA is evidence about the sample tested. It is not a medical approval, a guarantee of suitability for every experiment or evidence that a product is approved for human or veterinary use.

Details worth checking

A useful review starts with traceability. Confirm that the product name, batch or lot number and report identifier align with the material supplied. Review the test date, laboratory details, methods and units rather than relying on a single headline percentage.

• Product and batch or lot identification
• Laboratory name and report number
• Date tested and date reported
• Analytical method and measured result
• Units, specification or acceptance criteria
• Authorisation or report sign-off

Identity, assay and purity are different

Identity testing asks whether the sample is consistent with the stated material. Assay generally estimates the amount or concentration of a target substance. Purity describes the proportion represented by the target relative to detected components under a stated method. These terms should not be treated as interchangeable.

Results also depend on the method, reference standard, sample preparation and reporting limits. A number without its method and context is incomplete information.

Laboratory competence and scope

Accreditation can provide additional confidence that a laboratory has been independently assessed for technical competence. In Australia, NATA explains that ISO/IEC 17025 supports reliable testing, calibration, sampling and measurement results.

Accreditation should be checked against the laboratory's relevant scope because a laboratory may be accredited for some activities but not every possible test.