What a Certificate of Analysis Actually Proves, and What It Doesn’t

By Mike Vance, LabFirst Peptides labfirst.com/about/mike-vance/

Nine peptide suppliers shut down in the last year. Buyers who lost deposits mostly tell the same story afterwards: the vendor looked legitimate, the website was professional, and every product page carried a certificate of analysis. The paperwork was there. It just did not say what people assumed it said.

A certificate of analysis is a laboratory report on a specific batch of material. In chemistry supply it is the closest thing to a receipt for what is in the container, and reading one properly takes about ninety seconds. Most buyers spend four, looking for a number above ninety-nine per cent, and stop there.

That number is the least informative thing on the page.

Three measurements, sold as one

Purity, identity and content are separate tests answering separate questions, and they get collapsed into a single percentage all the time.

Purity asks what proportion of the material one substance is rather than a mixture. It is usually measured by high-performance liquid chromatography, which separates a sample into its components and reports the size of each. A result of 99% means the largest peak accounts for 99% of what came off the column.

It does not say the peak is the right substance. That is identity, and it takes a different instrument: mass spectrometry, which weighs the molecule and compares it against what the label claims. A vial can be 99% pure and 100% the wrong compound. Both statements fit on the same certificate, and only one of them is usually there.

Content is the third. A vial labelled ten milligrams can contain nine, with the remainder being water absorbed from the air or salt left from manufacture. The material is pure. The identity is correct. There is simply less of it than the label says. This is measured separately, and on most certificates, it is not measured at all.

A buyer reading “99%” has learned the answer to one of three questions and has no way to tell which two are missing.

The field that decides whether any of it is real

Everything above assumes the certificate is genuine. The single check that tests that assumption is whether the document can be verified at the laboratory that issued it.

Real analytical laboratories put a report number, a QR code or a lookup link on their work, and entering that code on the laboratory’s own website returns the same document. Not a PDF hosted by the seller. The laboratory’s site, the laboratory’s copy.

If a certificate carries no verification mechanism, it proves nothing about anything, because a PDF is a picture and pictures are trivial to alter. If it carries a mechanism that does not resolve, that is worse than none, and it is worth understanding why: somebody built the appearance of verifiability on purpose.

Three related things to check while you are there. The lot number on the certificate should match the lot on the container in your hand, because a real report for a different batch is still the wrong report. There should be a test date, since a certificate with no date could describe material from any year. And the document should state who submitted the sample. A report commissioned by the seller covers the material the seller chose to send, which may or may not resemble what ships to you.

What the closures had in common

Reading back through the suppliers that folded, the pattern is not fraud so much as absence. The certificates were often real documents from real laboratories. What was missing was the connective tissue: a lot number that tied the report to the box on the shelf, a date, a route to check it with somebody other than the seller.

That is a useful lesson for anyone buying laboratory materials, and it generalizes well past this industry. The question is never whether a supplier has documentation. Everyone has documentation. The question is whether any of it can be checked by someone who does not work there.

Reading one in ninety seconds

Six things, in order.

Is the issuing laboratory named, with a legal name rather than a logo? Is there a code, QR or link that resolves on that laboratory’s own site? Does the lot number match the container? Is there a test date? Is a method printed beside the purity figure, or just a percentage? And are identity and net content reported separately, or is the whole thing one number wearing three hats?

Six answers. If five are yes and no one is, you have learned something specific about where the supplier’s process stops. If four are missing, you have learned something about the supplier.

A word about my own position

I run a company that sells research chemicals, so I have an obvious interest in buyers caring about paperwork. It is worth saying where our own certificates stand, because it is a useful example of the difference between a certificate and a laboratory.

Our first thirty-two samples went to Optiq Health Labs and came back reporting zero for every analyte, across all thirty-two. We did not accept that as a real result. The same thirty-two went to Freedom Diagnostics, which returned purity at 98% or higher on all thirty-two. Same material, two laboratories, two completely different answers. That gap is the reason this article exists: a certificate is only as good as the laboratory behind it, and the way you find out which you are holding is by checking whether it verifies independently, not by reading the number on the page.

Freedom’s certificates are on our product pages, with a lookup code that resolves at Freedom’s own site rather than ours.

Which is, in a way, the whole point. A number is not proof. The ability to verify it somewhere other than the seller’s website is proof and in our own case, it is also how we found out our first laboratory’s zero was wrong.

Mike Vance runs LabFirst Peptides, a research-use-only chemical supplier in Santa Ana, California. A fuller guide to reading certificates, including the checks above, is at labfirstpeptides.com/coa.