How to Verify a Research Peptide Certificate of Analysis (2027)

A certificate of analysis is only as good as your ability to check it. An image of a report on a product page proves that someone had an image. This guide sets out a repeatable method for confirming a research peptide certificate with the laboratory that issued it, reading each field for what it actually says, and recognising the gaps a certificate leaves open. The worked example is a real Janoshik report from our own catalogue.

What a certificate of analysis is, and what it is not

A certificate of analysis (COA) is a laboratory's record of the measurements it made on one submitted sample, on one date. It describes that sample. It does not describe a product line, a supplier's process, or vials filled before or after the sample was taken. Everything that follows comes back to that one idea: a certificate is evidence about a specific piece of material, and your job is to establish whether that material is the material in front of you.

The fields on a Janoshik report

Before checking anything, know what each field on the report is. On the Janoshik reports in our catalogue:

What you need before you start

• The full report, not a cropped screenshot. Crops tend to remove exactly the fields you need: the task number, the date and the verify key.
• The task or report number the laboratory assigned. This is the lab's own reference for the analysis.
• The verify key, a code printed on the report that the lab's verification page accepts.
• The listing you are checking it against: compound, vial size and, where the supplier publishes one, the lot currently shipping.

If a supplier cannot give you all four, you cannot complete the check, and that is a finding in itself.

Step 1: confirm the issuing laboratory is named and independent

The report should name the laboratory that performed the analysis, and that laboratory should not be the seller. In-house analysis can be perfectly competent, but it cannot be confirmed by anyone outside the company, and a seller grading its own material has an obvious conflict of interest. A report that names no laboratory, or that carries only the supplier's own branding, cannot be traced.

Step 2: check the report at the laboratory, not at the supplier

This is the step that turns an image into evidence. Go to the issuing laboratory's own verification page, typed into the address bar yourself rather than followed from the supplier's link, and enter the task number and verify key. For Janoshik reports the page is verify.janoshik.com. The laboratory returns its copy of the result. Compare it, field by field, with the image you were given.

Any difference is decisive. A purity figure that differs in the third decimal place, a different sample name, or a different analysis date means the image you were shown is not the record the laboratory holds. There is no innocent reading of an edited certificate.

Step 3: match the sample name and size

The sample name is whatever the submitter wrote on the sample, transcribed by the lab. It will often be informal: a short name, a size, sometimes an internal code. What matters is that it plausibly names the compound and the vial size you are looking at. A 10 mg report presented on a 5 mg listing, or a report for one compound shown against a different one, is a mismatch however good the numbers look.

Step 4: read the batch field for what it actually says

The batch field is free text supplied by whoever submitted the sample. On some reports it carries a lot code; on many it carries a physical description such as a cap colour; on some it is blank, or reads "Unknown". None of these is wrong in itself, but each tells you something different about traceability:

• A lot code lets you ask the supplier to confirm that code is the lot you will receive.
• A cap colour or description is a weaker link: it identifies a fill, not a documented lot, and you should expect the supplier to say plainly which vials it corresponds to.
• A blank or "Unknown" field means the report itself does not tie the result to a lot. A supplier should say so on the listing instead of implying a lot match the paper does not make.

Step 5: read purity and content as two separate numbers

Purity and content answer different questions. Purity is the share of the detected material that is the main component, as a percentage. Content (often printed as quantity or net content) is the mass of material the laboratory measured in the vial, in milligrams. A sample can show high purity and a content well away from the label, or the reverse. Check both against the listing, and do not let a strong purity figure stand in for a content figure the report does not print.

Some reports carry no purity row at all. A coenzyme reported by content only, or a two-component blend reported as two separate contents, is a common case. The honest reading is "no purity figure was printed", not an inferred one.Janoshik reports peptide purity by HPLC; that method is not printed on the report itself. The report states purity; it does not include a separate identity test.

Step 6: check the date against the lot you will receive

The analysis date tells you when the sample was measured. It does not tell you when your vial was filled. A report from many months ago may still describe the lot currently shipping, if the supplier has not changed lots, or it may describe stock long gone. The supplier should be able to say which lot the report belongs to and whether that lot is the one being sold now.

Step 7: list what the report does not cover

Finish by writing down what the certificate leaves open. For a typical peptide report this list is longer than the list of what it covers: no identity result, no heavy metals, no microbial or endotoxin testing, no sterility, no residual solvent or counter-ion measurement. That list is not a criticism of the laboratory. It is a record of the limits of your evidence, and it keeps you from reading a purity number as a statement about anything else.

Worked example: a real report, field by field

Below is the GHK-Cu 100 mg report currently on file in our catalogue, reproduced from the same data as our public COA feed. Each report prints the sample name, the measured quantity per vial, a purity figure where the lab reported one, the analysis date and a verify key. It does not print an identity result or name the analytical method.

Applying the method: the laboratory is named; the task number and key go into Janoshik's verification page; the sample name and size are matched against the GHK-Cu product page; the batch field is blank, so the product page should not claim a lot match the report does not make; purity and content are read separately; the date is compared with what the page says about the current stock. The same steps apply to a report that does print a batch description:

Patterns that should stop the check

• The key does not verify, or verifies to a different sample. Regard the image as unreliable.
• One report on many listings. A single certificate shown on several different compounds or sizes cannot describe all of them.
• A blanket "all lots tested" claim with one report per compound. A claim that broad needs a report per lot to back it.

How we publish ours

Batch tested by Janoshik Analytical. Verify any report with its key on Janoshik's site. Each report we hold is published with its task number, date and verify key, and ourtesting page lists every report on file. A product with no report says "No certificate published yet" on its own page and claims no figure. Every figure in the examples above is what the report prints. You can run the steps on any of them, for example on the BPC-157, KPV oripamorelin product pages, or read the method in more depth inHPLC vs mass spectrometry.

Research use only. A certificate records a laboratory's measurements on one sample. It does not establish identity unless an identity test is printed, and it says nothing about suitability for any use. Ouralus materials are supplied for laboratory research use only and are not for human or animal use.