Research peptides in the UK: what 'not for human use' means

01The short version

"Research peptides" is the trade name for unlicensed peptides sold as freeze-dried powder in vials, labelled "for research purposes only, not for human consumption". In the UK the sector is legal, unregulated and uneven. This guide explains what the label means, how the market works, what a certificate of analysis should show, and the questions to ask any supplier.

02What 'not for human use' means

It is a legal device. Medicines law applies to products presented for a medicinal purpose. By selling a vial as a laboratory reagent, the seller avoids being a medicines supplier, and the responsibility for what happens next moves to the buyer. It says nothing about quality, purity or sterility. Some suppliers behind that label are careful; some are drop-shipping from unknown factories. The label does not tell you which.

03How the UK market works

Most UK "peptide labs" do not synthesise anything. They buy bulk powder from manufacturers, mostly in China, sometimes in the US, and either re-vial it or resell sealed vials. The better ones send samples to an independent UK or US lab for HPLC and mass spectrometry and publish the results. The rest publish the manufacturer's own sheet, or nothing. Prices are similar across the board, which tells you price is not a quality signal.

04How to read a certificate of analysis

A useful COA has: the product name and sequence, a lot number that matches your vial, the test date, the lab that ran it (with a name, not "our lab"), and results for identity (mass spec, confirming the molecular weight), purity (HPLC, as a percentage), and ideally endotoxin and residual solvents. A COA missing the lot number, the lab name or the identity test is a decoration. Our own raw-material certificate is published on the batch results page precisely so it can be judged on those criteria.

05Six questions for any supplier

1. Which lab tested this lot, and can I see the report with the lot number on it?
2. Was identity confirmed by mass spectrometry, or only purity by HPLC?
3. Where was the powder manufactured?
4. How is it stored before dispatch, and how is it shipped?
5. Is the company registered in the UK, and who runs it?
6. What happens if a vial arrives damaged or the result does not match?

A supplier who answers all six clearly is rare. One who answers none is common.

06The alternative: finished products

For the two peptides we work with, the answer to "which supplier" is to skip the vial entirely. A finished spray, assayed, preserved, metered and made by a UK company, removes reconstitution, sterility and dose error in one go. That is the argument for FOCUS-01 in vials vs a metered spray. For other peptides no such product exists, and the six questions are what you have.

COGENT makes two peptide nasal sprays, Semax (FOCUS-01) and Selank (CALM-02), and nothing else. We do not sell the compounds discussed below and this article does not recommend buying them. It exists because people search for these things and deserve an honest answer.