How to Spot a Fake Peptide COA: A Verification Checklist

A Certificate of Analysis (COA) is only worth as much as your ability to check it. PDFs are easy to edit, and a genuine report can be copied from another vendor’s site in seconds.

This checklist covers how to verify a report yourself. For what each section of a COA means, see our guide How to Read a Peptide Certificate of Analysis.

1. A named lab you can find and contact

A real COA names the laboratory that ran the analysis, not just the vendor’s logo. Find the lab on your own, by searching for it rather than clicking a link inside the PDF, and confirm it exists and offers peptide analysis.

Some labs hold ISO/IEC 17025 accreditation, the international standard for testing-lab competence. It is worth checking, but many labs serving this market do not hold it, so its absence is one data point, not proof of a fake. If you cannot find the lab at all, or the lab is the vendor itself, treat the report as a claim rather than evidence.

2. A report ID you can look up on the lab’s own site

This is the strongest single check. Many independent labs give each report a unique identifier and let anyone look it up on the lab’s website. Two examples:

• Freedom Diagnostics (US): each report carries an accession number and a search code. The search code is the first four letters of the client’s name followed by the accession number. The lab’s COA lookup page accepts the search code, the accession number, or the company name, and opens the lab’s own copy of the PDF.
• Janoshik Analytical: reports carry a task number and a verification key, which can be checked on Janoshik’s public verification site.

Compare the lab’s copy line by line with the vendor’s: compound, purity, lot, dates, and client name. Any difference means one of the two was changed. If there is no ID or no lookup tool, email the lab and ask them to confirm the report.

3. Dates that make sense

Most reports show when the sample was received and when it was reported. The report date should follow the received date with a plausible turnaround. An old report is not fake by itself, but if the product is described as a new batch, an old report may describe material that has long since sold out.

4. Whose name is on it: the client field

The client field names whoever sent the sample to the lab. It tells you a lot about what the report proves. There are three common situations:

• The vendor’s own name. The vendor submitted its own material for testing. This is the most direct link between the report and what that vendor sells.
• The manufacturer’s name. The vendor is showing the batch report of the company that made the peptide. This is common and not a sign of fraud, but it proves less. It shows that the manufacturer’s batch tested well, not that the vendor’s own stock was sampled.
• Another vendor’s name, or a blank or blurred field. This is a red flag. A report in a competitor’s name was most likely borrowed, and a blank client field makes the report impossible to attribute to anyone.

If the name is not the vendor’s, ask how its stock relates to the tested batch. A legitimate vendor can answer plainly.

5. The lot number, compared with your vial

A COA describes one batch. Check whether the lot on the report corresponds to the lot on your vial. If a vendor labels product with its own lot numbers, the two will not match character for character, and the vendor should be able to show which tested batch its lot came from.

Some manufacturers use a date-based production code as the lot, covering several compounds made in the same run. The same lot string on reports for different peptides is not proof of fraud if each report has its own ID and its own data, but it is less precise than a per-compound lot.

6. An identity test, not just a purity figure

An HPLC purity percentage tells you how much of the sample is one main component, not what that component is. Identity is usually confirmed by mass spectrometry (MS), which the United States Pharmacopeia describes as a technique based on measuring the mass-to-charge ratio of ions. The observed mass should match the mass calculated from the sequence.

A report that lists only a purity number, with no identity result, cannot rule out a clean sample of the wrong compound. Our guide HPLC vs Mass Spec: What Purity and Identity Testing Actually Tell You explains the difference in detail.

7. A chromatogram and a mass spectrum you can actually read

A genuine report usually includes the raw data behind the numbers: an HPLC chromatogram (signal against time) and, where MS was run, a mass spectrum (signal against mass-to-charge ratio). Look for:

• A main peak that is labeled and stands clearly above a readable baseline
• Smaller peaks left visible, not cropped out of the frame
• Axes with units and scales
• A labeled mass peak close to the expected value. A singly protonated ion, written [M+H]+, appears at the molecular mass plus about 1.
• Graphs that look like instrument output, and that differ from one report to the next

8. Purity math that adds up

HPLC purity is usually reported as area percent: the main peak’s area divided by the total area of all integrated peaks. If a peak table is included, the areas should add up to about 100% and the main peak’s share should equal the stated purity. Several sizeable peaks alongside a near-perfect figure means the numbers and the picture disagree. Treat a flat “100%” with skepticism too.

9. Signs of an edited PDF

• Fonts, sizes, or alignment that change inside one field, especially the purity, lot, or client name
• White boxes laid over the original text. Zooming in or trying to select the text can reveal them.
• Document properties (File > Properties in most PDF readers) naming an image editor as the creator, or a modified date well after the report date. Neither proves tampering, but both are worth asking about.
• A screenshot or photo of a report instead of the lab’s own PDF
• Internal mismatches. A Freedom Diagnostics search code, for example, starts with the first four letters of the client’s name, so a code that disagrees with the client field means something was changed.

10. The same report reused

Compare reports across a vendor’s catalog. The same report number, chromatogram, or three-decimal purity figure appearing on different products, or on a supposedly new batch, is a red flag. A report for a different vial size than the one you are buying can be legitimate, but ask whether it is the same batch.

The checklist at a glance

• The lab is named, real, and contactable
• The report ID resolves on the lab’s site, and the copies match
• Received and reported dates are plausible
• You know whose name is on it and what that means
• The lot on the report can be traced to your vial
• Identity is confirmed by mass spec, not just purity by HPLC
• A readable chromatogram and spectrum are attached
• The purity math agrees with the chromatogram
• There are no signs of editing
• The report is not reused across products or batches

How to check our own reports

Our products have named, independent lab reports that you can read before you buy, both on its product page and on our Lab Reports page. Our current reports come from Freedom Diagnostics, an independent US laboratory whose reports cover HPLC with UV detection coupled to mass spectrometry. Each one carries an accession number and search code that you can enter on Freedom’s lookup page to pull up the lab’s own copy.

To be plain about what those reports are: most of them are the manufacturer’s batch reports. The client name on them is the manufacturer’s, and the lot numbers are the manufacturer’s, not ours. We are moving to testing under our own name and our own lot numbers, and we will publish those reports as they arrive. If you want to know how a specific vial relates to a published report, contact us and we will tell you.

Frequently asked questions

Is a COA with another company’s name on it always fake?

No. Resellers often publish their manufacturer’s batch report, and that can be entirely genuine. It proves the manufacturer’s batch was tested, not the reseller’s own stock. A report in an unrelated competitor’s name usually means it was borrowed.

Can a real COA still not describe the vial I receive?

Yes. A genuine report describes only the sample that was tested. If your vial came from a different batch, the report does not speak for it.

What is the fastest single check?

Look up the report ID on the lab’s own website and compare the lab’s copy with the vendor’s. If the lab has no lookup tool, email the lab. If neither is possible, treat the purity figure as unverified.

Does a high purity figure prove the peptide is what the label says?

No. Purity by HPLC measures how clean a sample is, not what it is. Identity requires a separate test, usually mass spectrometry, with an observed mass that matches the calculated one.

What should I do if a report fails these checks?

Ask the vendor for a verifiable report ID or the lab’s own copy, or contact the lab directly. If neither can confirm the report, do not rely on it for your research records.

Sources

• Freedom Diagnostics, COA lookup (search by search code, accession number, or company name): https://freedomdiagnosticstesting.com/search-for-your-coa-based-on-the-unique-accession-number/
• Janoshik Analytical, public report verification: https://public.janoshik.com/
• United States Pharmacopeia, General Chapter <736> Mass Spectrometry: https://doi.usp.org/USPNF/USPNF_M99525_02_01.html
• United States Pharmacopeia, General Chapter <621> Chromatography: https://doi.usp.org/USPNF/USPNF_M99380_70101_01.html
• ISO/IEC 17025:2017, General requirements for the competence of testing and calibration laboratories: https://www.iso.org/standard/66912.html

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