Semax (ACTH(4–10) Analogue)
A synthetic heptapeptide derived from the ACTH(4–10) fragment with a C-terminal Pro-Gly-Pro extension, CAS 80714-61-0. The extension is what separates it from the parent fragment — and what changes its analytical behaviour.
Pricing and pack sizes
| Size | Cat. no. | Pack | Price per kit | Per vial |
|---|---|---|---|---|
| 5 mg | XA5 | 10 vials | $43.00 | $4.30 |
| 10 mg | XA10 | 10 vials | $50.00 | $5.00 |
| 30 mg | XA30 | 10 vials | $120.00 | $12.00 |
Prices are in USD and are per kit of 10 vials — not per vial. Both figures are shown so the two can be compared directly; a "per vial" price quoted without saying so is how the same material ends up looking ten times cheaper than it is.
Larger quantities, mixed kits and custom synthesis are quoted on request. Current lot documentation accompanies every quotation.
Monograph
| Compound | Semax — ACTH(4–10) analogue with C-terminal Pro-Gly-Pro |
|---|---|
| CAS Registry Number | 80714-61-0 |
| Molecular Formula | C37H51N9O10 |
| Monoisotopic Mass | 813.92 Da |
| Sequence | Met-Glu-His-Phe-Pro-Gly-Pro (MEHFPGP) |
| Residue Count | 7, linear, no disulfide bonds |
| Purity | ≥ 99.0% (RP-HPLC, UV 220 nm) |
| Identity Confirmation | ESI-MS, theoretical mass match |
| Appearance | White to off-white lyophilized cake or powder |
| Solubility | Soluble in water and aqueous buffers |
| Storage (lyophilized) | −20 °C, desiccated, protected from light |
| Documentation | Lot-specific COA with HPLC chromatogram and MS spectrum |
What Semax is
ACTH(4–10) is the minimal fragment of adrenocorticotropic hormone that retains behavioural effects in animal models without stimulating the adrenal cortex. Semax is that fragment with three additional residues — Pro-Gly-Pro — appended to the C-terminus.
The extension is not decorative. It changes the peptide's susceptibility to peptidase cleavage, shifts its behaviour on reverse-phase columns, and accounts for the 38 Da mass difference between Semax and the unmodified ACTH(4–10) core. A supplier that quotes a mass of 776 Da against a product labelled Semax has sold the parent fragment.
Semax is unmodified at the N-terminus: the methionine is free, not acetylated. It carries no disulfide bonds, so a single dominant HPLC peak and a mass match at 813.92 Da establish identity — but the methionine is a genuine oxidation site and should be visible in the charged-ion envelope if the material has aged.
Regulatory status — read this before ordering
Semax is a registered medicinal product in Russia, where it has been approved for clinical use since the 1990s. It is not approved by the FDA, EMA, MHRA, TGA, or any other Western regulator, and it is not licensed for import as a medicine in the United States, the European Union, the United Kingdom, or Australia.
This creates an asymmetry that the other compounds on this site do not have. A compound that is an approved drug somewhere is treated differently by customs authorities than a compound that is not a drug anywhere. Buyers in jurisdictions where Semax has no marketing authorisation should confirm that their intended use — reference standard, analytical calibrant, in-vitro assay — is lawful in their own country before ordering.
We supply Semax as a chemical reference standard, not as a medicine, and we make no representation that it is lawful to import for any purpose in any particular country. Buyers are responsible for their own import compliance.
Research context
The following summarises mechanisms reported in preclinical and in-vitro literature. It is provided for scientific orientation only and does not describe any approved or established clinical application in your jurisdiction.
Neurotrophin expression
The most frequently reported observation is upregulation of BDNF and NGF expression in cultured glial and neuronal cells, with downstream trkB signalling. Much of this work comes from a small number of research groups, which is worth weighing when reading the literature.
Peptidase resistance
The C-terminal Pro-Gly-Pro extension is reported to slow enzymatic degradation relative to the bare ACTH(4–10) fragment, which is the stated rationale for the modification. This is a stability claim rather than a pharmacological one and is measurable in plasma or buffer systems.
Cognitive and ischaemia models
Rodent studies report effects in models of cerebral ischaemia and in behavioural paradigms. These are animal models; no independent large-scale human trial data exist outside the Russian regulatory dossier.
Note on evidence status
The evidence base is unusual in this catalogue: there is a national regulatory approval and a body of Russian-language clinical literature, but very little independent replication in Western journals. Both facts should inform how much weight you place on the mechanism claims.
Analytical verification
- Purity — RP-HPLC. C18 column, gradient acetonitrile/water with 0.1% TFA, UV at 220 nm. Main-peak area percentage, acceptance ≥ 99.0%.
- Identity — ESI-MS. Deconvoluted mass compared against theoretical 813.92 Da. A value near 776 Da indicates the unmodified ACTH(4–10) core rather than Semax, and fails release.
- Oxidation check. The N-terminal methionine can oxidise (+16 Da). The chromatogram is inspected for the sulfoxide satellite, which is reported rather than excluded.
Look up your lot in the COA registry for the chromatogram and mass spectrum of the specific batch.
Preparing a standard solution
For preparing calibration standards for instrumental analysis. Not a preparation guide for any biological or human application.
- Equilibrate the sealed vial to room temperature before opening.
- Dissolve in sterile deionised water or an appropriate aqueous buffer down the vial wall; 0.1–1.0 mg/mL is typical for HPLC calibration.
- Swirl, do not vortex.
- Prepare fresh. The free N-terminal methionine oxidises readily; use the same day.
- No repeated freeze–thaw. Aliquot once, store at −20 °C or below, protected from light.
Frequently asked questions
What is the sequence of Semax?
Met-Glu-His-Phe-Pro-Gly-Pro — seven residues, written MEHFPGP. It is the ACTH(4–10) fragment with a C-terminal Pro-Gly-Pro extension.
How is Semax different from ACTH(4–10)?
ACTH(4–10) is the six-residue core, mass 776 Da. Semax adds Pro-Gly-Pro, giving 813.92 Da — a 38 Da difference. They are different molecules and are not interchangeable as standards.
Is Semax an approved drug?
In Russia, yes — it has been registered for clinical use since the 1990s. It is not approved by the FDA, EMA, MHRA, or TGA. We supply it as a chemical reference standard for in-vitro research, not as a medicine, and make no claim about import legality in your country.
What purity do you guarantee?
≥ 99.0% by RP-HPLC per released lot. The measured value for your lot is on its certificate of analysis.
Can I see the COA before ordering?
Yes — the batch registry lists lot number, assay date, testing laboratory, method and measured purity.
How should lyophilized Semax be stored?
−20 °C, desiccated, protected from light — stable for 24 months from the assay date. Ambient is acceptable during transit only.
Do you ship Semax internationally?
We ship to research institutions in most countries, but buyers are responsible for confirming that import and possession for their intended use is lawful where they are. Where a compound is a registered medicine elsewhere, customs treatment can differ from other research chemicals.
Is Semax approved for human use in my country?
Almost certainly not. It is not approved by the FDA, EMA, MHRA or TGA, and we supply it strictly as a reference standard for in-vitro laboratory research.
Research use only
This product is a chemical reference standard intended exclusively for in-vitro laboratory research and analytical method development. It is not a pharmaceutical, drug, food, food additive, cosmetic, or veterinary product, and it is not supplied for therapeutic use in any jurisdiction. It has not been evaluated or approved by the FDA, EMA, MHRA, TGA, or any other regulator outside Russia for any human or animal application, and it must not be administered to humans or animals.