Compound Quality
"Lab Tested" Means Nothing On Its Own. Three Lines On The Certificate Decide It.
Every supplier in this category says lab tested. It is two words in a headline and it costs nothing to type. The certificate underneath it is where the claim either survives or falls apart, and almost nobody opens it.
See this in the catalogue →
Open any listing in this space. Somewhere on the page it says lab tested, third-party verified, or independently analysed.
Now open the document behind it. That is where the difference lives, and there are only three lines that matter.
Identity. Is this molecule the one on the label? Mass spectrometry answers it. Without this line you have a vial of something.
Purity. Of the material present, what fraction is the right molecule? HPLC answers it. This is the number everyone quotes and the only one most certificates carry.
Net content. How many milligrams of the actual material are in the vial? A separate quantitative test. This is the line that goes missing.
Three lines. A certificate with one of them is not a certificate, it is a marketing asset with a letterhead.
Read the document before you read the headline.
This advertiser publishes third-party purity analysis for every lot they ship, searchable by product or lot number.
Open the COA library →1Purity is a ratio. It cannot tell you an amount.
A glass of orange juice can be 99% pure. That tells you nothing about whether the glass is full.
Research vials work the same way. Purity describes what is in there. It does not measure how much is in there. Those are two different laboratory methods and they produce two different numbers.
Which means a vial can be genuinely 99% pure and still hold meaningfully less material than the label claims. Both statements are true at once. Only one of them usually gets printed.
Purity says what it is. Net content says how much. A certificate with only the first has answered half the question.
2The missing weight is real, and it is not what you ordered
These materials leave manufacturing with other things attached. Residual salts from the process, and water the lyophilised powder pulls out of the air.
Neither of those lowers a purity figure, because purity only looks at the target fraction. Both of them take up weight in the vial. If the label says 10 mg and a share of that mass is salt and moisture, the material you paid for is whatever is left.
That is not fraud. It is chemistry. It only becomes a problem when nobody measures it and everybody quotes the purity number as though it settled the matter.
Weight in the vial and target material in the vial are not the same measurement.
3The lot number is what turns a document into evidence
Here is the trick that runs through this entire category.
A supplier publishes one PDF per product. It has a lab letterhead and a purity figure. It describes a batch that was tested once, at some point, and it is served to every buyer of that product forever.
Your vial came from a different batch. The document describes a batch you will never receive. It is real, it is signed, and it is about somebody else's order.
A lot-matched certificate is a different object entirely. The number on the document is the number on your vial.
Product level PDF: a document exists. Lot level certificate: your vial was tested.
Five of the fifteen certificates currently published. Every entry carries its own lot number, and most carry a test date. Open the index and check any of them against this page.
Type a lot number. Read the analysis.
The certificate for the batch on the shelf, published before you order rather than emailed after you complain.
Open the COA library →4Why the third line goes missing
Because it costs more.
Purity comes off a standard analytical run. Net content requires an additional quantitative method, and somebody has to ask the laboratory to run it and to report it.
A supplier who never orders that test is not hiding a bad result. They do not have a result. Neither do you. The number simply does not exist anywhere in the chain, and the vial ships regardless.
A missing line is not proof of a problem. It is the absence of proof, which is the problem.
5The thirty second check
Open the certificate for whatever you are about to buy. Do not read it end to end. Look for five things.
- A lot number, and the same one on the vial. Otherwise you are reading about a different batch.
- An identity line. Mass spectrometry confirming the molecule. This is the floor, not a bonus.
- A purity figure with a method named next to it. A percentage with no method is a number someone typed.
- A net content line. Either a milligram figure or a statement that it meets the label claim.
- A laboratory name and a date. Signed by the lab, not by the seller.
Five fields. Under a minute. It is the fastest way to separate two suppliers who look identical on the listing page.
| On the certificate | What it proves | What it cannot prove |
|---|---|---|
| Identity (MS) | The molecule is the labelled one | How much of it there is |
| Purity (HPLC) | The target fraction is clean | How full the vial is |
| Net content | The milligrams were measured | Nothing. This is the missing line. |
| Lot number | The test describes your vial | Nothing |
| No lot number | A document exists | Which batch it belongs to |
Three lines. Then decide.
Identity, purity and net content, on a dated certificate tied to the lot number on your vial.
Browse the lab-tested range →
Comments
Went back through five certificates I had saved. Every one had purity. Not one had net content. I had been treating them as complete documents for two years.
The product level PDF point is the one that stung. Mine is the same file on every listing, which I had somehow never noticed.
Checked the index linked here against the lot numbers in this article. They match, and the dates are there. That is the first time I have been able to audit a claim on an article like this.
The orange juice line finally made it land for me. A pure glass and a full glass are two different claims and I had been reading them as one.
Same. Also the point about a percentage with no method named. Half my saved PDFs just say 99% with nothing next to it.
Printing the five field check and keeping it next to the laptop. Took under a minute on the first supplier and they failed on two of them.