Selank + Semax 10+10mg

What is Selank + Semax ?

Selank + Semax 10+10mg is a pre-blended vial of two Russian-developed heptapeptides, 10mg of each, as lyophilised powder. Selank is Thr-Lys-Pro-Arg-Pro-Gly-Pro, an analogue of tuftsin. Semax is Met-Glu-His-Phe-Pro-Gly-Pro, an analogue of ACTH(4-10).

Both peptides come from the Institute of Molecular Genetics of the Russian Academy of Sciences and share one design. A short active fragment carries a C-terminal Pro-Gly-Pro tail that slows enzymatic breakdown. Both are registered medicines in Russia and hold no MHRA, EMA or FDA authorisation.

The two molecular weights are close, 751.9 and 813.9 g/mol, so this equal-mass blend is nearly equimolar: about 13.3 µmol of Selank to 12.3 µmol of Semax. The blend itself has no dedicated literature.

Selank + Semax Research Applications

• Selank and enkephalinases : it blocked breakdown of plasma enkephalin (IC50 15 µM), more potently than bacitracin or puromycin (Zozulya et al., 2001).
• Selank and gene expression : in rat frontal cortex it changed 45 of 84 neurotransmission genes within an hour, in step with GABA (Volkova et al., Front Pharmacol, 2016).
• Semax and neurotrophins : a 1.4-fold rise in hippocampal BDNF protein, with more trkB activation (Dolotov et al., Brain Res, 2006).
• Semax and ischaemia : smaller cortical infarcts in a rat model of focal ischaemia (Romanova et al., Bull Exp Biol Med, 2006).

The blend suits preclinical designs that would otherwise run both peptides from separate preparations, such as GABAergic and neurotrophin endpoints measured in one rodent cohort, or enzyme-inhibition assays. Its practical value is one reconstitution and one in-use window.

Selank + Semax vs the Components Alone

Each peptide has its own evidence base. Selank work centres on enkephalin-degrading enzymes and GABAergic gene expression. Semax work centres on BDNF and trkB signalling and ischaemia models. One study measured both side by side (Kost et al., Bioorg Khim, 2001). In human serum, Semax inhibited enkephalin-degrading enzymes with an IC50 of 10 µM and Selank with 20 µM. No controlled study has tested the co-formulated mixture. Once dissolved the ratio is fixed, so designs needing independent concentrations, a single-peptide control or attribution to one mechanism need the separate vials.

Research Overview

This is the pre-blended presentation, a single lyophilised vial containing Selank 10mg and Semax 10mg. The blend pairs two Russian-developed nootropic heptapeptides: Selank, a synthetic analogue of the immunoglobulin-derived tetrapeptide tuftsin (Thr-Lys-Pro-Arg-Pro-Gly-Pro, 751.9 g/mol, CAS 129954-34-3), and Semax, a synthetic analogue of the ACTH(4-10) fragment (Met-Glu-His-Phe-Pro-Gly-Pro, 813.7 g/mol, CAS 80714-61-0). Both have been studied for anxiolytic and cognitive effects in animal models and early human research, with the Selank literature weighted towards anxiety-related mechanisms and the Semax literature towards neurotrophin biology and neuroprotection.\n\nBoth compounds share a design origin, the Institute of Molecular Genetics of the Russian Academy of Sciences, and one stabilisation strategy: a C-terminal Pro-Gly-Pro extension protecting a short active fragment from rapid enzymatic degradation. That shared chemistry is why they are so often studied side by side, and why a co-formulated vial is a natural format for designs running both. What the blend as a format gives is procedural: one vial means one reconstitution, one fill volume, one solution and one in-use window, removing a transfer step along with its sterility and volumetric error. What it removes is independent control. The two components cannot be separated after reconstitution, and an equal-mass blend is not automatically equimolar, though the arithmetic here is unusually forgiving. The two molecular weights differ by only 62 g/mol, so 10mg of each corresponds to roughly 13.3 µmol of Selank against 12.3 µmol of Semax, close to a true 1:1 molar ratio.\n\nThe honest position on the pairing is that no controlled study has evaluated this specific combination, and the blend should be treated as two separate compounds in one container. Each component carries its own literature: Selank has been reported to inhibit enkephalin-degrading enzymes (Zozulya et al., Bull Exp Biol Med, 2001) and to alter the expression of GABAergic neurotransmission genes in rat brain (Volkova et al., Front Pharmacol, 2016), while Semax has been reported to upregulate hippocampal BDNF and trkB (Dolotov et al., Brain Res, 2006) and to reduce infarct volume in a rat model of focal cerebral ischaemia (Romanova et al., Bull Exp Biol Med, 2006). The primary literature for both compounds is largely Russian in origin and lacks extensive independent Western replication, and neither compound holds a marketing authorisation from the MHRA, EMA or FDA. In-vitro laboratory research use only.

Storage and Reconstitution

Keep sealed vials at -20°C, away from light and moisture. After reconstitution, keep the solution at 2-8°C and use it within 4 weeks, or freeze single-use aliquots at -20°C. Both peptides share one reconstitution date, so aliquot at the start and avoid repeated freeze-thaw cycles.

Vials are sold on their own, without bacteriostatic water for mixing or other supplies.

How to reconstitute and handle

Treat the vial as one 20mg preparation, with the fill volume set by the concentration your protocol needs. Let the vial and the bacteriostatic water reach room temperature and swab both stoppers. Add the water slowly down the inside wall and swirl gently until dissolved. Do not shake or vortex. The solution should be clear and colourless. The N-terminal methionine of Semax oxidises in air and light, so keep stopper-open time short. Label the vial with fill volume, concentration and date.

• Treat the vial as 20mg of total peptide at a fixed internal ratio. The blend cannot be split into its components after reconstitution, so a protocol requiring the two at independently chosen concentrations needs separate vials rather than this format.
• Molar arithmetic is unusually simple for this pairing. The two molecular weights differ by only 62 g/mol, so the equal-mass blend is close to equimolar, roughly 13.3 µmol of Selank against 12.3 µmol of Semax.
• Introduce the diluent slowly down the inner glass wall and swirl gently until the solution is clear and colourless. The N-terminal methionine of the Semax component is oxidation sensitive, so minimise headspace, stopper-open time and light exposure.
• Both components share one reconstitution date, so the shorter of the two in-use windows governs the vial.
• Aliquot into single-use volumes and avoid repeated freeze-thaw cycles. Verify on the certificate of analysis that both components have been resolved and assayed separately rather than reported as a single combined figure.

For the full method, see the peptide reconstitution guide and the reconstitution calculator.

Research References

• Selank inhibits enkephalin-degrading enzymes (Zozulya et al., Bull Exp Biol Med, 2001)
• Selank affects gene expression in GABAergic neurotransmission (Volkova et al., Front Pharmacol, 2016)
• Semax regulates BDNF and trkB expression in rat hippocampus (Dolotov et al., Brain Res, 2006)
• Neuroprotective effects of Semax in experimental cerebral infarction (Romanova et al., Bull Exp Biol Med, 2006)
• Semax and Selank inhibit the enkephalin-degrading enzymes of human serum (Kost et al., Bioorg Khim, 2001)

Published research on Selank + Semax is indexed on PubMed. See our full UK buyer's guide for Selank + Semax Blend.