Guide
Verifying a lot
"Verified per lot" is a claim that can be checked, and this page sets out how. A laboratory receiving a Dohrna vial should be able to read five fields off the label, find the same five on a certificate, and confirm that the certificate describes the material on the bench. The process takes a minute, and it is the whole point of issuing certificates per lot rather than per compound.
Step one: read the label
Every Dohrna vial label carries:
- the compound name;
- the catalogue number of the line;
- the lot number of the batch;
- the expiry date; and
- a code that opens the product page on dohrna.com.
The lot number is the field that identifies the batch. Everything else on the label describes the line; the lot number describes this particular production of it.
Step two: open the certificate
The product page for the line — reached from the code on the label, or from the catalogue — carries a Certificate of Analysis card. The certificate for the current lot is published there with the lot number stated in the caption. Where more than one lot is in circulation, each has its own certificate.
If the card shows a placeholder rather than a certificate, the lot has not yet been released for publication. The certificate can be requested by email to support@dohrna.com, quoting the catalogue number and lot number from the label, and will be sent as a file. Nothing is published before the laboratory has issued it.
Step three: match the five fields
The certificate should agree with the label on every one of these:
| Field | On the label | On the certificate |
|---|---|---|
| Compound name | Printed name | "Sample" or "Product" line |
| Catalogue number | Printed | Stated in the header |
| Lot number | Printed | "Lot" or "Batch" line |
| Nominal quantity | Milligrams stated | "Quantity" or "Fill" line |
| Laboratory | — | Named on the certificate, with its accreditation reference |
The lot number is the decisive match. A certificate with the right compound and the wrong lot is a certificate for a different batch and does not describe the vial.
Step four: check the certificate against the specification
With the right certificate in hand, the analytical figures can be read against the product page's Specification section, which states the molecular formula, the calculated molecular weight and the salt form for the line. The observed mass on the certificate should agree with the calculated molecular weight within the stated tolerance; the salt form should match. The companion guide, Reading a Certificate of Analysis, explains each figure.
What to do with a mismatch
A field that does not match is a question for support@dohrna.com, with the catalogue number, the lot number and a description of the difference. The most common explanation is that a newer certificate has been issued for the lot and the page has not yet been updated; the next most common is a labelling error at fill, in which case the vial is replaced. A mismatch is not resolved by assuming the closest certificate applies.
Why this matters
A certificate that cannot be tied to a lot is a description of a compound in general, and any supplier can publish one. A certificate tied to a lot number that appears on the label is a description of the material actually sent. The second is the only kind Dohrna publishes, and it is why the lot number is the first thing to read.
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