Semax vs Selank
The two best-known Russian neuropeptides, sharing a Pro-Gly-Pro stabilization strategy but derived from different parent molecules.
Neuroactive
Semax
Heptapeptide ACTH(4-10) analog studied for BDNF expression and neurotrophic signaling, without corticotropic activity.
Neuroactive
Selank
Heptapeptide analog of tuftsin studied for effects on BDNF expression and GABAergic signaling.
Side by side
| Dimension | Semax | Selank |
|---|---|---|
| Molecular weight | 813.92 g/mol | 751.88 g/mol |
| Size class | short peptide | short peptide |
| CAS number | 80714-61-0 | 129954-34-3 |
| Research area | cognitive | cognitive |
| Sequence | Met-Glu-His-Phe-Pro-Gly-Pro | Thr-Lys-Pro-Arg-Pro-Gly-Pro |
| Available sizes | 10mg | 5mg, 10mg |
| Entry price | $49 | $36 |
| Cost per mg | $4.90 | $4.90 |
Mechanism
Semax
Semax is a synthetic analog of ACTH fragment 4-10, extended with a C-terminal Pro-Gly-Pro sequence that markedly increases stability against peptidase degradation. The design goal was retention of the neurotropic effects attributed to the ACTH fragment while eliminating its corticotropic activity — the fragment does not stimulate steroidogenesis. Published work reports rapid upregulation of BDNF and NGF expression in hippocampal tissue. As with Selank, most primary literature is Russian-language and requires translation.
Selank
Selank is a synthetic heptapeptide derived from the immunomodulatory tetrapeptide tuftsin, extended with a Pro-Gly-Pro sequence that substantially increases stability against peptidase degradation. Research has examined its effects on BDNF expression in the hippocampus, monoamine turnover, and enkephalin degradation. The literature originates largely from Russian institutional research and much of the primary work requires translation.
Evidence quality
Mechanism is not the same as evidence. Where we have assessed the literature, the verdict is stated plainly.
Semax
Evidence base: coherent and moderately sized, concentrated in one model system with gene expression as the dominant readout. Functional and clinical endpoints are less represented. The Pro-Gly-Pro fragment has activity of its own, which complicates attribution.
Full research reference →Selank
Evidence base: modest and concentrated in provenance, with gene expression as the primary readout rather than behavioural or clinical endpoints. Search results require manual filtering because of name collisions.
Full research reference →Research applications
Semax
- BDNF and NGF expression profiling in hippocampal tissue
- Dopaminergic and serotonergic system interaction studies
- Neuroprotection assays in ischemia models
- Peptidase stability studies of Pro-Gly-Pro extended analogs
Selank
- BDNF and neurotrophic factor expression studies
- GABAergic and serotonergic system interaction assays
- Enkephalin degradation and peptidase inhibition research
- Anxiety-related behavioral models in rodents
Common questions
What is the difference between Semax and Selank?
Semax is heptapeptide ACTH(4-10) analog studied for BDNF expression and neurotrophic signaling, without corticotropic activity. Selank is heptapeptide analog of tuftsin studied for effects on BDNF expression and GABAergic signaling. They differ in molecular weight (813.92 vs 751.88 g/mol) and in the pathways they are studied against.
Which is more cost-effective per milligram, Semax or Selank?
Semax is lower at approximately $4.90 per milligram at its best tier, against $4.90 for the other. Cost per milligram is only meaningful relative to the concentrations a given protocol requires, since these compounds are not used at comparable masses.
Can Semax and Selank be studied together?
Combination designs appear in the published literature for a number of these compounds. Whether it is appropriate for a given protocol depends entirely on the model and endpoint. We supply research compounds and do not provide protocol guidance — consult the primary literature for your specific model.
How should Semax and Selank be stored?
Store lyophilized at -20°C protected from light. Reconstituted at 2-8°C for up to 30 days. For Selank: Store lyophilized powder at -20°C protected from light. Reconstituted solution stable at 2-8°C for up to 30 days.
Which has the stronger evidence base?
Semax — Evidence base: coherent and moderately sized, concentrated in one model system with gene expression as the dominant readout. Functional and clinical endpoints are less represented. The Pro-Gly-Pro fragment has activity of its own, which complicates attribution. Selank — Evidence base: modest and concentrated in provenance, with gene expression as the primary readout rather than behavioural or clinical endpoints. Search results require manual filtering because of name collisions.
All products sold on this website are intended for research and identification purposes only. These products are not intended for human dosing, injection, or ingestion.
Comparison generated from Lyra Vital catalog data. Every specification is reconciled against the certificate of analysis for the shipped batch.