QUALITY DOCUMENT GUIDE
How to Read a Urolithin A COA
A certificate of analysis is useful only when its results, limits and lot identity match the material you are buying or testing.
Use this guide when comparing a sample with a proposed commercial lot. It is a review framework, not a COA for a released Urolithin A batch. Request the current document from the supplier and confirm its issue date and scope before approving material.
Start with document and lot identity
Check the product name and identifier, manufacturer or issuing party, specification number and version, batch or lot number, manufacture or packing date where provided, and the COA issue or release date. Compare those identifiers with the sample label and purchase documents. A representative COA is useful for seeing the report format, but it cannot prove the result of a later lot.
Ask whether the test result is a release result for that batch, a typical value, a subcontracted laboratory result or an informational observation. If the sample and COA numbers differ, pause the review until the relationship is documented.
Read each result against a method and limit
| COA field | Question for QA | Common gap |
|---|---|---|
| Identity | Which reference and method establish the stated molecule? | A product name without an identification result. |
| Assay | Is the result reported as-is or on a dried basis, and which HPLC method and standard were used? | Comparing percentages calculated on different bases. |
| Related substances | Are named and unknown peaks covered by stated limits? | A single purity figure without an impurity profile. |
| Contaminants | Which residual solvents, elemental impurities and microbiological tests apply? | Assuming every panel is identical across markets. |
| Physical attributes | Are appearance, moisture or particle size release criteria or observations? | Treating visual similarity as an assay result. |
HPLC is a method family, not a result by itself. Request the detector, reference standard, sample preparation, calculation basis and relevant validation summary when a specification comparison depends on them. LC-MS can add identity information in an investigation, but it does not remove the need to define acceptance criteria.
Compare sample, quotation and commercial lot
Record the sample lot and COA in your supplier review sheet. When the quote names a different grade, pack or lot, request the corresponding specification and release documentation. Note any retest date, storage statement and packaging configuration. Finished-product compatibility and stability remain separate checks.
Where an independent result is required, define sampling and chain of custody before asking a laboratory to test the material. The third-party testing guide explains that sequence. Return to quality control for the broader batch review or use the RFQ brief to request the current documents.