Semax is one of the most searched neuropeptides among South African research labs, and it is one of the few compounds in the Biolabs range that comes in three formats: a lyophilised vial, a pre-filled pen and a nasal spray. If you have been searching for "Semax South Africa", this guide covers the essentials: what Semax is, its sequence and specifications, what published laboratory research has looked at, how the three formats compare, and how to store and document it properly.
Semax, Selank and our other nasal spray, vial and pen formats are listed together in our peptides South Africa collection.
What is Semax?
Semax is a synthetic heptapeptide (a peptide made of seven amino acids). It was developed at the Institute of Molecular Genetics of the Russian Academy of Sciences in Moscow. Structurally, it is built from the 4–7 fragment of adrenocorticotropic hormone (ACTH), Met-Glu-His-Phe, with a Pro-Gly-Pro tripeptide added to the C-terminus. In the literature it is usually described as an analogue of the ACTH(4–10) fragment.
The Pro-Gly-Pro (PGP) extension is the defining design feature. Short ACTH fragments are broken down quickly by peptidases, and the PGP tail is generally described as slowing that enzymatic breakdown. The same PGP extension appears in Selank, a related heptapeptide built on the tuftsin sequence, which is why the two compounds are often discussed together.
Semax structure and specifications
The sequence and physical data below match the PubChem record for Semax (CID 9811102) and the specifications on our product pages.
Met-Glu-His-Phe-Pro-Gly-Pro
One-letter code: MEHFPGP
Key specifications at a glance
- Length: 7 amino acids, linear
- Molecular formula: C37H51N9O10S
- Molecular weight: 813.9 g/mol
- CAS number: 80714-61-0
- Research material: synthetic peptide made by solid-phase peptide synthesis, supplied as a lyophilised (freeze-dried) powder or as a ready-made solution
- Sulfur content: the N-terminal methionine contains a thioether, which can oxidise over time if the material is exposed to air, light and heat
That methionine detail matters in the lab. Methionine oxidation adds 16 Da to the measured mass, so it is one of the things a mass spectrometry result on a certificate of analysis can reveal. When you review a Semax COA, the measured mass should sit close to the expected value for the sequence above.
What has Semax been studied for in the lab?
All of the work summarised below is preclinical research in rodent models or tissue. It is described here only as scientific background, not as evidence of any effect outside a laboratory setting.
BDNF and neurotrophin studies
The most cited line of Semax research looks at brain-derived neurotrophic factor (BDNF), a signalling protein involved in synaptic plasticity. A 2006 study in the Journal of Neurochemistry (Dolotov et al., PMID 16635254) reported specific, calcium-dependent binding sites for radiolabelled Semax in membranes from the rat basal forebrain. It also measured increased BDNF protein levels in that brain region a few hours after the peptide was given to rats, but not in the cerebellum.
Gene-expression studies
Researchers at the same institute have used genome-wide transcriptional analysis to see which genes change in response to Semax. A 2014 study in BMC Genomics (Medvedeva et al., PMID 24661604) studied rat cortex tissue in an experimental model of focal cerebral ischaemia. It reported that Semax mainly altered the expression of genes linked to the immune system, including genes encoding chemokines and immunoglobulins, and a smaller group of genes linked to the vascular system.
Monoamine neurochemistry
A 2005 study in Neurochemical Research (Eremin et al., PMID 16362768) measured dopamine, serotonin and their metabolites in the rodent striatum after Semax was given. The authors reported a rise in the serotonin metabolite 5-HIAA. Semax alone did not change dopamine levels, but it changed the response to a second compound given afterwards.
These studies come mostly from a small number of research groups, and many questions remain open. That is part of why Semax continues to attract laboratory interest.
Semax formats in South Africa: vial, pen or nasal spray?
Biolabs supplies Semax in three formats, each at 10 mg. They contain the same compound, but each suits a different laboratory workflow.
Lyophilised vial
The Semax 10 mg lyophilised vial is the most stable format for storage and shipping, because freeze-drying removes the water that drives most peptide degradation. It needs to be reconstituted before use. Solvents and accessories are in our reconstitution supplies and hardware collection, and our bacteriostatic water guide explains the options.
Pre-filled pen
The Semax Peptide Pen holds a ready-made solution, so there is no reconstitution step. Pens are made to order, must stay refrigerated at 2–8 °C and are sent by overnight cold-chain courier. If you are in an area without reliable overnight delivery, the vial is the safer choice. Our pens vs vials guide compares the two formats in more detail.
Nasal spray
The Semax 10 mg Nasal Spray is a ready-made aqueous solution of 10 mg in 8 ml, in a spray-pump bottle. Like the pen, it is a solution format, so it should be refrigerated at 2–8 °C after opening, protected from light and kept capped. Much of the published Semax literature uses intranasal application in rodent models, which is one reason this format is so commonly requested. You can see the full range in our nasal sprays collection.
Storage and lab handling for Semax
Lyophilised powder
Store unopened vials at −20 °C for long-term storage or 2–8 °C for shorter periods, away from light and moisture. Sealed vials handle ordinary courier transit at ambient temperature well. Let a vial reach room temperature before opening it, so condensation does not form on the powder.
Reconstitution
Laboratories typically use sterile water or bacteriostatic water (0.9% benzyl alcohol). Add the solvent slowly down the inside wall of the vial and swirl gently rather than shaking. Label the vial with the date and concentration, store the solution at 2–8 °C and follow your own validated protocol for how long it remains usable.
Solutions: pens and sprays
Keep solution formats refrigerated at 2–8 °C, protected from light and never frozen. Because methionine can oxidise, it also makes sense to keep caps closed and limit how long a solution sits at room temperature during handling.
Reading a Semax COA
Every Biolabs batch is tested by an independent laboratory for purity (HPLC) and identity (mass spectrometry). When you review a Semax certificate, check that:
- the batch or lot number matches the number on your vial, pen or spray,
- the HPLC purity is shown with a chromatogram, not just a single number,
- the measured mass matches the expected mass for MEHFPGP (813.9 g/mol average), and
- the test date and the name of the testing laboratory are stated.
Semax certificates are published on our Certificates of Analysis page, so you can check a batch before you order.
Semax FAQ
Where can I buy Semax in South Africa?
Biolabs ships Semax nationwide from local stock in vial, pen and nasal spray formats. Vials go by tracked courier; pens go by overnight cold-chain courier.
What is the difference between Semax and Selank?
Both are synthetic heptapeptides that end in the same Pro-Gly-Pro extension. Semax is built on an ACTH fragment (Met-Glu-His-Phe), while Selank is built on the tuftsin sequence (Thr-Lys-Pro-Arg). They are different compounds with different molecular weights and separate bodies of research.
Is Semax for human use?
No. Semax is sold strictly for laboratory research and is not for human or veterinary use.
Sources
- PubChem compound summary: Semax, CID 9811102 (sequence, formula, molecular weight, CAS number).
- Dolotov OV et al. Semax, an analogue of adrenocorticotropin (4-10), binds specifically and increases levels of brain-derived neurotrophic factor protein in rat basal forebrain. J Neurochem. 2006;97 Suppl 1:82-6. PMID 16635254.
- Medvedeva EV et al. The peptide semax affects the expression of genes related to the immune and vascular systems in rat brain focal ischemia: genome-wide transcriptional analysis. BMC Genomics. 2014;15:228. PMID 24661604.
- Eremin KO et al. Semax, an ACTH(4-10) analogue [...], activates dopaminergic and serotoninergic brain systems in rodents. Neurochem Res. 2005;30(12):1493-500. PMID 16362768.
Research use only: All Biolabs products, including Semax in every format, are supplied strictly for laboratory research by qualified researchers. They are not for human or veterinary use, not for consumption, and are not medicines, foods, supplements or cosmetics. Nothing in this article is medical advice or a claim of any effect. Research summaries describe published preclinical studies only. The purchaser is responsible for safe handling and for complying with applicable South African regulations.