How to read a Certificate of Analysis (COA)
A COA is the single most useful document for judging what's actually in a vial. It can't make an unapproved peptide safe — but knowing how to read one (and spot a fake) separates a tested product from a hopeful guess.
What a COA is — and isn't
A Certificate of Analysis is a lab report describing a specific batch (lot) of a substance: what it is, how pure it is, and what else was found. A good one comes from an independent third-party lab, names the testing methods, and ties the results to a lot number and date you can match to your vial.
A COA proves testing, not safety or legality. A peptide can be 99% pure and still be unapproved, mis-dosed for you, or risky for your body. Purity answers "is this the right molecule, mostly free of junk?" — not "is this safe for me to inject?"
The fields you'll see, and what each one tells you
Field
What it means / what to look for
Product name & sequence
The peptide identity, often with the amino-acid sequence and molecular formula. Cross-check it against the profile on this site — the name, formula, and weight should match.
Lot / batch number
Must match the number printed on your actual vial. A COA for a different lot tells you nothing about what you're holding.
Date of analysis
Recent is better. An old COA reused across many batches is a red flag — each batch should be tested.
Purity (HPLC)
Usually given as a percentage by High-Performance Liquid Chromatography. Reputable material is typically ≥98%. HPLC separates the target peptide from related impurities and truncated byproducts.
Identity / mass (MS)
Mass Spectrometry confirms the molecule actually is what the label claims, by measuring its molecular weight. Purity without an identity (MS) confirmation is half a result — it can be very pure… of the wrong thing.
Net peptide content
How much of the powder is actually peptide versus water, counter-ions, and salts. A vial can be "99% pure" yet only ~80% peptide by mass — which changes the real dose. Sometimes reported alongside water (Karl Fischer) and acetate/TFA content.
Counter-ion (acetate / TFA)
Peptides are usually salts. TFA (trifluoroacetate) is common from synthesis but less desirable than acetate; high residual TFA is worth noting.
Appearance
Typically "white to off-white lyophilized powder." Useful but weak — appearance can't reveal identity or contamination.
Endotoxin / sterility
For anything intended to be injected, bacterial endotoxin and sterility matter enormously. Most grey-market "research" COAs omit these entirely — which tells you the product was never validated as injectable-grade.
Heavy metals / residual solvents
Better COAs report these. Their absence isn't proof of contamination, but their presence on the report is a sign of a more thorough lab.
A worked example
Hypothetical COA — reading it critically.
Peptide
BPC-157 (formula/MW should match our profile)
Lot #
BPC-2406-A ← must equal the vial
Date
2026-05-02 recent — good
Purity (HPLC)
98.7% acceptable
Identity (MS)
1419.5 Da, consistent identity confirmed — good
Net peptide
82.3% real dose is ~82% of powder weight — note this
Endotoxin
not reported ← not validated as injectable-grade
Read this way, even a "98.7% pure" COA carries two quiet caveats: the usable dose is lower than the label weight, and nothing here speaks to sterility.
Red flags
- ✗No COA at all, or "COA available on request" that never arrives. Treat as a no.
- ✗Lot number doesn't match your vial, or there's no lot number on the COA.
- ✗Purity (HPLC) but no identity (MS). You can't confirm it's the right molecule.
- ✗"100% pure" or impossibly clean numbers. Real assays have detection limits and noise.
- ✗The same COA image reused across different products or lots, or an obviously edited PDF/image.
- ✗No named lab, no method, no date. A result with no source is not a result.
- ✗Seller's own in-house COA only, with no independent third-party report to corroborate it.
- ✗No endotoxin/sterility data on something you intend to inject.
How to actually verify one
- Match the lot. Confirm the COA's lot number and date match the physical vial in front of you.
- Check the identity line. Make sure there's an MS result and that the reported mass matches the molecule's known weight (cross-reference the peptide's profile here).
- Find the lab. A named, contactable third-party lab is far stronger than an anonymous or seller-generated sheet. Some labs will confirm a report's authenticity if you ask.
- Consider an independent retest. The gold standard is sending a sample to an independent analytical lab yourself — the only way to verify your vial rather than a document about it.
- Remember what it can't tell you. A clean COA still doesn't establish that a dose is right for you, that the product is sterile unless tested, or that the substance is legal to use.
Bottom line: a verifiable, recent, third-party COA with both purity (HPLC) and identity (MS) is the minimum evidence that a vial contains what it claims. It is necessary, not sufficient — and its absence is a clear answer on its own.