How to Read a Peptide Certificate of Analysis (COA)
What a complete certificate of analysis includes, the red flags that make a COA meaningless, and how to match a live AccuVerify record to the lot code on the vial.
A Certificate of Analysis (COA) is the document that verifies what is in a research vial matches what is on the label. For research materials, it is the difference between documented quality and a guess. Here is how to read one, and what separates a meaningful certificate from a decorative one.
What a complete COA includes
A thorough certificate for a peptide research material reports five things. Identity confirmation, typically by mass spectrometry, verifies the molecular weight matches the target sequence. Purity, typically by HPLC, is expressed as a percentage of the main peak; Peptagon's published lots verify between 99.0% and 99.98%. Measured quantity reports the actual milligrams in the vial rather than the nominal fill. Endotoxin (LAL) and sterility (PCR) screening document that the lot passed contamination checks. Appearance and the lot number tie the record to a specific production batch.
Red flags
Be cautious with certificates that are undated, missing a lot number, missing measured quantity, or produced by an in-house lab with no independence from the seller. A certificate that cannot be matched to the vial in hand documents nothing.
How Peptagon handles COAs
Testing is performed by Accumark Laboratories, an independent US lab. Each published lot has a live digital AccuVerify record hosted by the testing lab itself, linked from the product page and the catalog card. Match the lot code on the record to the lot code printed on the vial to confirm the certificate covers that exact batch.
A COA is a quality document, not a claim of suitability for human use. All Peptagon products are for laboratory research use only.
