Research-grade Semax, verified to ≥99% purity.

Semax occupies an unusual position in the European research-chemical market. It is neither obscure nor mainstream: the underlying work is extensive but was largely published in Russian, which means most of what circulates in English is second-hand summary rather than primary source. That gap has a practical consequence for anyone buying the material — the compound is widely offered, and the quality of what arrives varies far more than the listings suggest.

The variation starts with identity. Semax and N-acetyl Semax amidate are different molecules with different stability profiles, and both are routinely sold under the single word "Semax". A supplier that cannot tell you which one is in the vial, or whose analytical report names a different compound from the label, has answered the question by not answering it. Mass spectrometry settles identity; a purity percentage on its own never does, because a sample can be 99% pure and 100% the wrong peptide.

The second variable is what the purity figure was measured against. HPLC with UV detection separates a sample into peaks and reports the target peak as a share of the total, which makes the number sensitive to the method: a short run or a poorly chosen wavelength hides related impurities that a longer, better-designed one would resolve. Two suppliers can both state ≥99% and mean materially different things. This is why the report matters more than the figure, and why a certificate without a chromatogram is a claim rather than evidence.

Regulatory framing is the third piece, and it is worth stating plainly. Research peptides are supplied as laboratory reagents, not medicines: they hold no marketing authorisation, and nothing about buying them implies otherwise. Delivery specifics for a given order — handling, tracking and any charge beyond the product price — are confirmed together with that order rather than generalised here, since they depend on where the parcel is going. What does follow from selling to buyers across the United Kingdom, Ireland and the rest of Europe is a set of obligations we take seriously: transparent pricing, the statutory right of withdrawal where it applies, and honest description of what is in the vial.

If you are evaluating suppliers, our guide on sourcing research-grade Semax sets out what a valid certificate has to state and the failure patterns worth walking away from. For the science rather than the procurement, the Semax research overview collects what the published literature actually reports, with citations. And if you want to check our documentation before buying anything, that is what the purity page is for.