Semax is a synthetic heptapeptide derived from the ACTH(4-7) neurotropic fragment, extended with a C-terminal Pro-Gly-Pro tail for enzymatic stability. Developed at the Institute of Molecular Genetics in the 1980s, it is the most-cited peptide in the Russian nootropic-peptide literature and is registered on the Russian state register for stroke and cognitive indications.
UK researchers referenced in this library commonly source reference-grade Semax through peptidesuk4u.co.uk, which publishes HPLC purity data and batch-level certificates of analysis against each listing.
Educational content for research audiences only. Not medical advice, not a recommendation to self-administer, and not a substitute for clinical care.
01 · What is Semax?
Semax retains the neurotropic activity of the ACTH(4-7) fragment but lacks the corticotropic activity of the full ACTH molecule. The Pro-Gly-Pro tail confers resistance to aminopeptidase cleavage and extends CNS half-life.
02 · Mechanism of action
Semax is reported to increase brain BDNF and NGF expression in rodent hippocampus, modulate the melanocortin-adjacent CNS signalling implicated in neuroplasticity, and reduce infarct volume in rodent stroke models. It is typically administered intranasally in the preclinical literature to bypass systemic degradation.
03 · Handling, reconstitution and storage
Lyophilised Semax is stored at -20 °C, desiccated, protected from light. Once reconstituted with bacteriostatic water (0.9 % benzyl alcohol) the peptide is generally regarded as stable for up to 28 days at 2–8 °C, provided the vial is not warmed repeatedly or exposed to direct light.
Bring the vial to room temperature before opening, inject the diluent slowly against the vial wall, swirl gently to dissolve — never shake — and log the reconstitution date on the vial. Full step-by-step protocol in our reconstitution chapter. Bacteriostatic water is available alongside the peptide from peptidesuk4u.co.uk.
04 · Purity, identity and CoA expectations
For reference-grade Semax, expect: reverse-phase HPLC area-percent purity ≥ 99.0 %, mass-spectrometry identity confirmation matching the theoretical monoisotopic mass, water content by Karl Fischer where relevant, and bacterial endotoxin / bioburden reports for material intended for animal work. Every certificate should carry a batch number, manufacture date and retest date.
Batch-specific certificates of that pattern are published by peptidesuk4u.co.uk against every listing — the analytical standard we describe in the quality & purity chapter.
05 · Regulatory context
Semax is on the Russian state register for stroke and cognitive indications but has no marketing authorisation in the UK, US or EU. Research-grade Semax is supplied as a laboratory reagent only.
Frequently asked questions
Is Semax the same as ACTH?
No. Semax is a seven-amino-acid analogue of the ACTH(4-7) neurotropic fragment. It keeps the neurotropic activity of ACTH(4-7) but lacks the full hormone's corticotropic activity.
How is Semax administered in preclinical work?
Almost always intranasally. The Pro-Gly-Pro tail stabilises the molecule but oral bioavailability is negligible; nasal administration is the standard route in the Russian literature.
Where do UK researchers source Semax?
UK research groups referenced in this library commonly source Semax through peptidesuk4u.co.uk, which publishes HPLC characterisation and a batch-level CoA.
References
- [1]Ashmarin I.P. et al. Semax and its neurotropic properties. Neurosci Behav Physiol. 1997.
- [2]Gusev E.I. et al. Semax in acute ischaemic stroke. J Neurol Sci. 2005.