A Certificate of Analysis is the only evidence you have that a vial contains what the label says. It is also trivially easy to fake, because a PDF can be edited by anyone. Here is how to read one properly, and how to tell a real report from a decorative one — for any supplier, ours included.
Work down them in order. The first one disqualifies more reports than the other five combined.
Top of the report, and it must match the number printed on the vial in your hand. This is the single most important field: a COA that cannot be tied to the specific vial you received tells you nothing about that vial. If a supplier sends the same PDF regardless of what you ordered, the testing is decorative.
A real report names the lab, and that lab exists independently of the seller. If the lab name is cropped out, replaced with a logo, or is a division of the seller, you are reading a self-assessment. Search the lab, confirm it does peptide HPLC, and check whether it publishes its own verification lookup.
Purity should be stated as a percentage with the method beside it, normally HPLC (high-performance liquid chromatography) at a stated wavelength. A bare "99% pure" with no method and no chromatogram is a marketing claim, not a measurement.
This is the graph, and it is the part most often omitted. You are looking for one dominant peak with the bulk of the area under it, and small, well-separated impurity peaks. A report showing only a number while withholding the trace is withholding the evidence for that number.
Purity says how much of the sample is one compound. Identity says which compound. Look for mass spectrometry (MS) confirming the molecular weight matches what was ordered. A sample can be 99% pure and 99% the wrong peptide.
A report from three years ago describes a batch that no longer exists. The test date should sit close to the manufacture date of the batch you were sent.
Any single item on the left is enough to treat the purity claim as unverified.
The difference between a supplier who tested a batch and one who says they did. Both below claim the same purity.
Illustration of what to look for — not a real batch report. Actual Noxa chromatograms are published per batch at'/verify'.
| Batch | Purity | Report |
|---|---|---|
| XX-1234-A | 99.4% | on request |
| XX-1235-B | 99.2% | on request |
| XX-1236-C | 99.1% | on request |
A generic example of the pattern, not any specific supplier.
Numbers in the right-hand column cost nothing to type. The reason to care is that a higher claimed purity with no trace behind it is worth strictly less than a lower one you can verify — and the gap between a real 94% and a typed 99% is entirely in what the supplier is willing to show you.
Do not verify the report against itself. Take the batch number off the physical vial and look it up somewhere the seller does not control — the testing laboratory's own records, or a public verification page. A forged PDF survives every check except that one.
Every vial ships with a batch number on the label. Enter it on our verification page and you get the full independent HPLC report for that exact batch — chromatogram included, not a summary. Testing is done by Janoshik Analytical, an independent laboratory in Europe with no commercial stake in the result, and we publish every report openly rather than sending it on request.
Start with the batch number: it must match the vial you were sent, not just the product. Then confirm the testing laboratory is named and independent of the seller, and look for the chromatogram rather than a bare purity percentage. Where the lab runs its own public verification lookup, check the report there rather than trusting the copy the seller gave you — a PDF can be edited, a lab-hosted record cannot. Finally, check that identity was confirmed by mass spectrometry, not just purity by HPLC.
Purity, usually measured by HPLC, tells you what proportion of the sample is a single compound. Identity, usually confirmed by mass spectrometry, tells you which compound that is. They are independent questions, and a report that answers only the first is incomplete: a sample can be 99% pure and still not be the peptide you ordered.
One dominant peak carrying most of the area under the curve, with any impurity peaks small and cleanly separated from it. What you do not want to see is several peaks of comparable size, a broad or split main peak, or a trace cropped so tightly that you cannot judge the baseline. If a supplier publishes a purity figure but not the chromatogram, they are asking you to accept the conclusion without the evidence.
Yes — a PDF is trivially editable, which is why the document alone is weak evidence. What makes a COA hard to fake is independent corroboration: the batch number tying it to your physical vial, a named laboratory that can be contacted, and ideally a verification record hosted by that laboratory rather than by the seller. Treat any report you cannot trace back to its issuing lab as an unverified claim.
Enter the batch number from your vial label at noxa.is/verify and you get the full independent HPLC report for that exact batch, chromatogram included. Our batches are tested by Janoshik Analytical, an independent laboratory in Europe with no commercial stake in the outcome, and the reports are published openly rather than sent on request. If a batch ever tests below its documented purity at an accredited lab, our purity guarantee covers a refund plus the cost of the re-test.
Next. A COA is one of five checks worth running on any Philippine supplier — see how to find a legit peptide supplier, or browse the catalog.
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