Seven steps, one lot number
A lot arrives sealed
Each lot is a single synthesis run, delivered in sealed vials with the manufacturer's own analysis. We give it a lot number at this point and quarantine it. Nothing from a quarantined lot can be sold.
Peptidarium · intakeWe send vials to the lab, not samples
Sealed vials from the lot go to [Independent lab] unopened, chosen at random from the delivery. The lab opens them. That means the result describes the same vials you receive, not a sample we prepared.
Peptidarium · dispatch to labPurity by HPLC
The lab dissolves the contents and runs reverse-phase HPLC, which separates the peptide from anything else in the vial. Detection is by UV at 220 nm, where the peptide bond absorbs. Purity is the main peak's share of the total area under all peaks.
[Independent lab] · RP-HPLCIdentity by mass spectrometry
The same solution goes through electrospray mass spectrometry, which weighs the molecule. The lab reports the mass it found. If it does not match the expected mass for that peptide within the instrument's tolerance, the lot fails, whatever the HPLC says.
[Independent lab] · ESI-MSCheck against the limits
We compare the lab's figures with the limits in the table below. A lot that misses any limit is rejected and returned. We do not sell a failed lot at a discount or under another name.
Peptidarium · release decisionPublish the certificate
The lab's report is added to the lot register unedited, with the lot number, the test date and the lab's name. The product page shows which lot is on sale and links to it.
Peptidarium · lot registerLabel, pack, dispatch
Each vial label carries the lot number. Your order confirmation lists the lot for every item, with a link to its certificate. Entering the number on the vial into the lot register opens the same document.
Peptidarium · fulfilmentLimits a lot must meet
| Test | Method | Limit | If it fails |
|---|---|---|---|
| Purity | RP-HPLC, UV 220 nm | ≥ 98.0% main peak | Rejected |
| Identity | ESI-MS | Found mass within instrument tolerance of expected | Rejected |
| Appearance | Visual | White to off-white lyophilised powder, cake intact | Rejected |
| Seal | Visual | Crimp and cap intact on every vial sampled | Rejected |
| Net peptide content | Lab report where available | Reported, not limited | Shown on certificate |
Limits are ours. The lab reports figures; we decide release. [Scientific editor] signs off this page and any change to the limits is logged.
Reading the chromatogram
The trace on each certificate is the HPLC output. Time runs left to right; the height shows how much is coming off the column at that moment. One tall peak with a flat baseline is what a clean lot looks like.
What the certificate does not tell you
HPLC purity is a share of what is detected at 220 nm. It does not count water or salts, which do not absorb there. That is why a 10 mg vial of a 99% pure peptide can contain less than 9.9 mg of peptide. Where the lab reports net peptide content, we print it; the calculator explains how to use it.
Common questions
Who does the testing?
[Independent lab], an accredited analytical laboratory with no ownership link to Peptidarium. Its name and location are on every certificate.
Is every lot tested, or just the first one?
Every lot. A new synthesis run is a new lot, with a new number and a new certificate.
Can I check a certificate is real?
Enter the lot number from your vial in the lot register. It shows the same report the lab sent us. If you want to go further, contact the lab with the report number.
What happens to a lot that fails?
It is returned to the supplier. We log the failure internally. We do not sell it, blend it or relabel it.
Why do you say "identity confirmed" rather than a percentage?
Mass spectrometry answers a yes-or-no question: is the molecule's mass the one expected? Purity is the percentage; identity is the match.