Information only. We do not sell products or give medical advice. Consult a licensed physician / healthcare professional.
Most guides teach you to read a Certificate of Analysis one number at a time. This one starts with what a complete certificate has to contain and how to check each field against the others and against the label on the vial. It is a reading guide for lab documents. Information only, we do not sell.
The method
A Certificate of Analysis is the minimum quality record a tested batch already has on file. Read it in this order and each check narrows what the document can and cannot prove.
A certificate that does not carry a lot number describes some past production run, not the unit in front of you. Look for the lot or batch field near the top, beside the compound name and issue date.
A lot or batch number printed on the certificate, in the header block.
In-house "QC" is the producer grading its own work. A meaningful COA comes from an independent laboratory, ideally one accredited to ISO/IEC 17025, whose name and accreditation reference appear on the page.
A named laboratory with an accreditation reference you can look up with the accreditation body.
Headline numbers are easy to type. The HPLC chromatogram and the LC-MS mass spectrum are the data behind them. A percentage with no chart behind it is a claim, not a measurement.
The chromatogram and the mass spectrum as images in the report itself.
Compare the lot number on the certificate with the number printed on the vial or its packaging. If they differ, the document describes a different batch from the one in your hand.
The lot on the label appears on the COA, character for character.
The field list
Use this list as a reading checklist. Every line is something an accredited laboratory already measures, so a genuine batch certificate can show all of it.
The reading
After the four checks, you are judging the document. These signals separate a certificate that supports a claim from one that only decorates it.
What the report measures
A complete certificate reports purity, identity, water, and endotoxin: four methods, four results. These are the four fields to confirm are present before you read anything else.
The proportion of target compound, with the chromatogram attached so the main peak is visible.
Molecular mass confirmation that the compound is what the label claims, not an analogue.
Residual water content, which lowers the true net peptide mass in lyophilized material.
Bacterial endotoxin in EU/mg or EU/mL, relevant for cell-culture and in-vivo research.
Why the source matters
Every check in this kit comes back to one question: who ran the test? A producer issuing its own Certificate of Analysis is grading its own work, and in-house QC is not the same as an independent, accredited laboratory. A third-party lab, ideally accredited to ISO/IEC 17025, produces a certificate free of commercial incentive and uses validated, auditable methods.
If a document cannot name its laboratory, that absence is itself the finding. International reference points (WHO quality principles, ISO/IEC 17025 laboratory competence, pharmacopeial methods from the USP) form the shared vocabulary a genuine COA speaks.
Framing: WHO quality principles · ILAC on accreditation · USP methods. Updated November 2026.
Questions
A lot number, purity by HPLC with the chromatogram, identity by LC-MS with the mass spectrum, water content by Karl Fischer, endotoxin by the LAL assay, and the name and ISO/IEC 17025 accreditation reference of the issuing laboratory. Each result should tie back to a named lab and one specific batch.
Very little. A sheet with no lot number, no chromatogram, and no named lab may reflect real testing of some earlier run, but it cannot be tied to the material you hold. Treat it as background information, not as evidence about your batch.
The lot number is the traceability key. A COA only says something about your material if the lot on the certificate matches the lot printed on the vial. Compare the two before you rely on any other figure in the report.
No. A COA records what a laboratory measured in one batch. It does not authorise a medicine, change a substance's legal status in any country, or replace medical advice. Research peptides are not approved medicines.
No. Get the COA is an information and education resource. We do not sell products, do not capture email, and do not give medical advice. We explain how to read and check a Certificate of Analysis. Consult a licensed physician before considering any use.
The verification kit
The kit collects the four checks, the field list, and the holds-up / does-not-hold-up signals on one page, plus the PDF guide.
Peptides discussed here are research materials where applicable, not consumer goods and not approved medicines. Legal status varies by country. Nothing here recommends use, dose, or a source of supply. Anyone considering these substances should consult a licensed physician who can assess their individual situation.