A Certificate of Analysis is the only piece of paper that separates a real research peptide from a sugar-pill scam. This guide walks through every section of a CoA, what the numbers actually mean, and the specific red flags that mean a certificate cannot be relied on.
What a CoA actually is
A Certificate of Analysis (CoA) is a one-page lab report describing what's inside a specific vial or batch of peptide. A legitimate CoA is produced by a third-party laboratory, not the in-house QA team of the company whose product it is, and is tied to a specific batch number that you can verify against the label on the vial you received.
If the CoA isn't dated, doesn't reference a batch number, or comes from a lab that doesn't exist, it's marketing, not testing.
The three tests that matter
1. Identity (LC-MS or MALDI-TOF)
Liquid Chromatography-Mass Spectrometry confirms the molecule in the vial is the peptide on the label. The report shows a measured mass that should match the theoretical mass of the peptide to within a few daltons. Without an identity test, you have no proof the vial contains what you think it contains: just a purity number for "something".
2. Purity (HPLC)
High-Performance Liquid Chromatography separates the peptide from impurities and reports purity as a percentage. Research-grade peptides are typically 97-99% pure. Anything under 95% should be treated as suspect. Look for the chromatogram itself. A clean single peak vs a forest of small peaks tells you more than any number.
3. Peptide content (Quantitative HPLC)
This is the test most company-issued CoAs skip. Quantitative HPLC measures how much of the labelled mg is actually peptide, as opposed to mannitol, salts, or moisture. A vial can be 99% pure but contain only 60% of the labelled mg.
The red flags
No batch number on the CoA, or a batch number that doesn't match your vial.
Identity test missing. Purity alone is meaningless if you don't know what was tested.
"Lab" name with no website, no address, and no verifiable credentials. Legitimate laboratories identify themselves and describe any relevant registration or accreditation accurately.
CoA dated months before your vial was manufactured. A company reusing one old CoA across many batches.
Image-only CoA with no chromatogram. A real HPLC report includes the chromatogram trace; a photo of a number is not evidence.
How LabDoc verifies CoAs
Every CoA aggregated on LabDoc is parsed, the lab name is matched against a list of known third-party laboratories, and identity/purity/content fields are extracted with the original chromatogram preserved. Companies can't edit numbers after submission. Results are categorised as Pass (≥95% HPLC, identity confirmed), Needs Review (one test missing), or Fail.
Checking a certificate, step by step
Find the certificate for the specific compound and the batch number on the vial.
Confirm identity, purity, and ideally peptide content are all present and recent.
Cross-check the lab name: is it a real third-party lab or the seller's own brand?
Look the batch up on LabDoc's results index, where each result covers only the sample tested.
Frequently asked questions
Is a company's own CoA enough?
No. A CoA written by the company or its in-house QA team is marketing material, not independent verification. Only a third-party laboratory's report is.
What's the minimum acceptable purity?
LabDoc's pass threshold is 95% by HPLC. Results for research-grade material commonly fall in the 97-99% range.
Why does peptide content matter if purity is already high?
Purity is a ratio; content is an absolute amount. A 99% pure vial that's mostly mannitol contains very little actual peptide. Both numbers are needed to know what is actually in the vial.
Where can I see independent results?
LabDoc's results index lists every result LabDoc has published. Each covers only the sample tested.