Laboratory guides
How to read a certificate of analysis
Read a certificate as an evidence chain: which sample was tested, by which method, what result was obtained and against which criterion it was interpreted. A compound name or isolated percentage does not complete that chain.
Source editorial review:
Start with the sample, not the percentage
Compare the vial identifier with the document. If laboratory sample codes appear, request the documented link between them. Do not correct a mismatch by hand or assume that the commercial name is sufficient.
Distinguish the report issuer from the sample supplier. A named institution or logo does not establish that it tested this lot; use an official issuer channel when authentication is needed.
Case: two reports both say 99%
Before comparing them, identify what each number measures. Relative chromatographic area is not automatically mass fraction or vial content. Method, sample and integrated signals also matter. Keep the unit and definition with the result.
Conclude only what was tested
Record identity, purity, content and any other actually included determination separately. If sterility or endotoxin tests are absent, leave them as not evaluated. A scientific reference in Asciende’s library likewise does not replace a material dossier.
A record for this decision
Does the document actually answer your question about this batch?
| Field | What to document |
|---|---|
| Correspondence | Name, variant, sample identifier and received batch. |
| Determination | Method, result, unit, criterion and analysis date. |
| Limit | What was not measured or which attachment is needed to interpret the result. |
When to leave the decision open
A chromatographic area result does not fill gaps in content, identity, endotoxin or sterility information. Request each determination by name.
Questions and answers
Does a COA confirm every claim on a product page?
It can support only determinations performed on the identified sample, within the method’s scope and limitations.
What if the lot does not match?
Leave the association unconfirmed and request the correct traceability before using that report to accept the material.