How to Read a Peptide Certificate of Analysis
Every seller says their peptides are pure. A lab report called a certificate of analysis is where that claim is proven — or quietly skipped. Here is what each number on it really means, and how to check one before you buy.
The certificates we use as examples are our own published lab results, batch numbers included. That way you can check our thinking against real documents instead of just taking our word for it.
“Third-party tested” (tested by an outside lab) now means very little in this market. You see it on almost every Canadian peptide site. Often there is no certificate at all. Or the certificate names no batch, no lab and no test method.
A certificate of analysis is a lab report about one specific batch of product. If you cannot link it to the vial in your hand, it is just decoration. This guide walks through the parts that matter, using real certificates. It shows what a weak result looks like, and a strong one too.
The five parts that matter
1 · Purity, and how it was measured
Purity is how much of the sample is the peptide you want, not other stuff mixed in (impurities). A purity number means little unless the test method is listed next to it. HPLC-UV is the standard purity test. It splits the sample into its parts and measures each one. Mass spectrometry (a test that weighs molecules) checks that the molecule is the right one. That is a different question.
A trustworthy certificate names the test method. Some just say “99%+ pure” with no method, no chromatogram (the test’s graph) and no lab. Treat those as ads.
Retatrutide · Purity (HPLC-UV) · 99.70%
2 · Content found vs. content expected
Most buyers skip this part, but it may be more useful than purity. It shows how much peptide the lab really found in the vial. It compares that with the amount on the label.
Slightly over the label is normal and expected. Makers add a little extra. That way the vial still holds the full amount after small losses during filling and freeze-drying. Our KPV batch tested at 11.65 mg for a 10 mg label. The NAD+ batch came in at 498.02 mg for a 500 mg label. Neither is unusual.
Well under the label is the red flag. If a vial tests below the amount on its label, you are not getting what you paid for. Any math based on the label will also be wrong.
KPV · Content found 11.65 mg (10 mg expected) · 116% of label
3 · Batch number
This is the most important part, and the one most often missing. A batch number is a code for one production run. A certificate covers just one batch. If the batch number on the certificate is not on your vial, the certificate does not describe your product.
Our batch codes look like RH-RETA-10mg-050826 or WB-BPC-10-022026 — source, compound, strength, date. The exact format matters less. What matters is that a code exists and can be traced.
4 · Appearance
Almost all research peptides ship lyophilized, which means freeze-dried. The certificate should call it a white or off-white powder or cake. It is a small detail, but a useful double-check. The certificate may say white lyophilized powder. If the vial holds something off-colour, clumpy or already liquid, stop and ask before you do anything else.
Appearance · White Lyophilized Powder
5 · The lab that did the test
“Third-party” means a lab that gains nothing from selling you the product. A certificate should name the lab and the test date. An unnamed lab is not a third party. And a certificate with no date could describe product made years ago.
Our certificates come from Lab Testides. We publish the original PDF, exactly as we got it.
Real results, including our weakest one
Below are the batches we publish right now. We included our lowest result, not just the ones that look good. A page that shows only 99%+ numbers tells you nothing. It does not show how a seller acts when a number is less impressive.
| Compound | Purity (HPLC) | Content found | Batch |
|---|---|---|---|
| PT-141 10 mg | 99.89% | 11.39–11.46 mg | PT10-0726 |
| SS-31 10 mg | 99.89% | 10.91 mg | SS10-0801 |
| KPV 10 mg | 99.87% | 11.65 mg | WB-KPV-10-022026 |
| MOTS-c 10 mg | 99.85% | 9.76 mg | RH-MOTS-10mg-050826-02 |
| Kisspeptin 10 mg | 99.85% | 10.94 mg | KS10-0731 |
| GHK-Cu 50 mg | 99.80% | 50 mg expected | — |
| Retatrutide 10 mg | 99.70% | 10.25 mg | RH-RETA-10mg-050826 |
| Semaglutide 10 mg | 99.66% | 11.42 mg | OZ10-0526 |
| NAD+ 500 mg | 99.65% | 498.02 mg | WTF-NAD-500-102225 |
| BPC-157 10 mg | 99.38% | 10.85 mg | WB-BPC-10-022026 |
| BPC-157 + TB-500 | 99.34% | 22.36 mg | WB-BPCTB-20-022026 |
| TB-500 10 mg | 99.27% | 11.09 mg | — |
| MOTS-c 20 mg | 99.08% | 22.82 mg | MO20-0712 |
| Semax 10 mg | 99.05% | 10.69 mg | SX10-0710 |
| Tesamorelin 10 mg | 98.90% | 10.80 mg | TE10-0729 |
| GHK-Cu 100 mg | 96.26% | 100 mg expected | — |
The GHK-Cu 100 mg batch tested at 96.26% — the lowest number on this page, and about three points below the rest. That is a real number from a real certificate. It is still a usable research-grade result. But it is not 99%, and we will not pretend it is. If every certificate a seller posts shows the same perfect number, ask questions. Do not just feel reassured.
Two entries show an expected amount but no amount found. Sometimes a certificate reports purity but not the amount found. Then we publish what the lab gave us. We do not fill in the gap ourselves.
What should make you walk away
Red flags on a certificate
- No batch number, or a batch number that does not match your vial. Then the certificate is about someone else’s product.
- “COA available on request.” If the report exists, it can be posted. This wording usually means you get it after you pay, if ever.
- A picture with no real document behind it — a cropped screenshot of a test graph, or a purity number typed into an image. Ask for the PDF the lab sent.
- The same certificate used for different products. One report cannot describe two compounds.
- No named lab, or no test date.
- No test method listed. A purity number without HPLC next to it is just a number. It is not a real measurement.
- Content testing under the label. Over is normal. Under means the vial is short.
Storage and handling
Freeze-dried (lyophilized) peptides are fairly sturdy. That is the point of freeze-drying. It is why they can ship within Canada at room temperature without breaking down. Things change once the vial is opened.
- Unopened and freeze-dried: keep cool, dark and dry. The fridge makes it last longer. A short trip at room temperature does not ruin it.
- After mixing (reconstitution): keep in the fridge. Mixed peptide breaks down much faster than powder. It must be used much sooner.
- Do not freeze and thaw it again and again. That breaks peptides down faster than keeping them in the fridge.
- Keep away from light. When mixing, aim the liquid down the side of the vial, not right onto the powder.
Our reconstitution calculator does the math for you. It shows how much bacteriostatic water to add and how much to draw, for any vial size.
Buying in Canada
An order shipped from inside Canada does not cross a border. So there is no customs hold and no import trouble. That is the practical reason most buyers prefer a seller in Canada. Orders placed Monday to Friday ship the same business day by Canada Post Xpresspost. They usually arrive in one to three business days, with tracking on every order. We ship to FlexDelivery addresses and PO boxes. Shipping is free over $199.
One thing to say plainly: all our sales are final. Because of the kind of products we sell and how we track stock, we cannot accept returns or exchanges. That is exactly why we post the certificates before you buy, not after. The test results are there for you to look at before you decide.
Common questions
What purity should I expect?
Research-grade peptides usually test at 98–99%+ by HPLC. Our published batches range from 96.26% to 99.89%. Be wary of any seller whose certificates all show the same perfect number. Real batches vary.
Why is the amount found higher than the label?
It is on purpose. A little is lost during filling and freeze-drying. So makers add slightly extra to make sure the full amount on the label is there. An amount below the label is the one that should worry you.
Does a certificate prove the product is safe?
No. A purity certificate tells you what a batch is made of — how much of the sample is the compound it should be. It is not a safety check. It does not test for germs (sterility) or toxins from bacteria (endotoxins) unless those results are listed on their own. And it says nothing about whether a compound is right for any use.
How do I match a certificate to my vial?
Compare the batch number on the vial label with the batch number on the certificate. They must match. If your vial has no batch number at all, no certificate can be linked to it.
What is the legal status of these products in Canada?
In Canada, peptide products meant for human use count as drugs. Health Canada must authorize them before they can be sold for that use. The compounds sold here are not authorized by Health Canada. They are sold only for lab research. They are not for people or animals to take. Putting “for research use only” on a label does not, by itself, change the rules for a product. If you want an approved treatment, talk to a licensed doctor or pharmacist.
Research use only. All products on this page are sold for lab research. They are not for people or animals to take. They are not authorized by Health Canada, and they are not medicines. Nothing on this page is medical advice. It is not a suggestion to give any compound to a person or animal. Certificate numbers describe only the batches named, and no others.
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Zenova Peptides
For laboratory research purposes only. Not for human use. Not medical advice.