Semax and Selank are among the most extensively documented cognitive research peptides in the scientific literature, both developed in Russia at the Institute of Molecular Genetics and studied across neuroprotection, cognitive function, and anxiolytic mechanisms. Sequence Labs supplies both compounds in research-grade lyophilized form, with batch-level COAs and PA-C catalog review.
ACTH(4-7) Analog · Neuropeptide
Semax
Met-Glu-His-Phe-Pro-Gly-Pro
- Structure: Synthetic heptapeptide derived from residues 4–10 of adrenocorticotropic hormone (ACTH). The core active fragment is ACTH(4-7) with a C-terminal Pro-Gly-Pro extension for enhanced stability.
- Origin: Developed at the Institute of Molecular Genetics, Russian Academy of Sciences. Registered as a pharmaceutical in Russia; subject of over 100 peer-reviewed publications.
- Research areas: BDNF (brain-derived neurotrophic factor) modulation, neuroprotection model studies, cognitive function research frameworks, serotonergic and dopaminergic pathway investigation.
- Available forms: Standard Semax (base peptide sequence) and N-Acetyl Semax Amidate — a modified form with acetylation at the N-terminus and amidation at the C-terminus, studied for enhanced stability and altered activity profiles in research settings.
- Research delivery context: Published research includes both intranasal (nasal spray) buffer solution protocols and reconstituted vial formats. Peptide nasal spray research uses specific buffer solutions not included in standard lyophilized supply.
Tuftsin Analog · Heptapeptide
Selank
Thr-Lys-Pro-Arg-Pro-Gly-Pro
- Structure: Synthetic heptapeptide analog of tuftsin — an endogenous tetrapeptide (Thr-Lys-Pro-Arg) with the addition of Pro-Gly-Pro to extend metabolic stability and prolong activity in research models.
- Origin: Developed at the Institute of Molecular Genetics, Russian Academy of Sciences, alongside Semax. Registered as a pharmaceutical (anxiolytic) in Russia and Belarus; documented in peer-reviewed research since the early 2000s.
- Research areas: Anxiolytic mechanism studies, GABAergic system modulation research, immune modulation pathways (particularly IL-6 and interferon activity), cognitive and memory research models. Frequently studied alongside Semax in combined cognitive research protocols.
- Research delivery context: Like Semax, intranasal administration is the most studied delivery route in the published literature. Research protocols using Selank typically specify buffer formulation and concentration parameters.
- Combined research: Semax and Selank have been studied in combination in peer-reviewed research examining complementary mechanisms — Semax in neurotrophic contexts, Selank in GABAergic and immune-modulation contexts.
Side-by-Side
Semax vs. Selank — Research Profile Comparison
Both compounds share Russian origins and a lyophilized supply format, but differ substantially in their studied mechanisms and research applications.
| Research Parameter | Semax | Selank |
|---|---|---|
| Peptide Class | ACTH(4-7) analog (neuropeptide) | Tuftsin analog (immunopeptide) |
| Amino Acid Sequence | Met-Glu-His-Phe-Pro-Gly-Pro | Thr-Lys-Pro-Arg-Pro-Gly-Pro |
| Primary Research Focus | BDNF modulation, neuroprotection, cognitive models | Anxiolytic mechanisms, GABAergic system, immune modulation |
| Neurotrophic Research | BDNF, VEGF, NGF pathway studies | Limited neurotrophic focus; primarily GABAergic |
| Immune System Research | Some IL studies; secondary interest | Primary focus — IL-6, interferon modulation |
| Modified Form Available | N-Acetyl Semax Amidate (enhanced stability) | Standard form; no acetylated variant |
| Sequence Labs SKUs | 5mg vial · 10mg vial | 5mg vial · 10mg vial |
| Storage Requirement | Lyophilized; −20°C | Lyophilized; −20°C |
| QA / Testing | Krause Analytical (Austin, TX) | Krause Analytical (Austin, TX) |
Research Context
Extensive literature.
Growing Western interest.
Semax and Selank have accumulated a substantial body of peer-reviewed research, primarily within Russian and Eastern European clinical literature. Semax has been studied across neuroprotective models, BDNF signaling pathways, and ischemia research. Selank has been studied in anxiolytic mechanism contexts, with documented research on GABAergic system interactions and cytokine modulation.
Western research interest has grown considerably, particularly within neuropeptide and nootropic research communities, as the compounds remain outside the FDA pharmaceutical classification framework and are therefore accessible for research supply. All content on this page is framed for informational and research reference purposes only — no therapeutic or clinical claims are made.
PubMed References
Search the published literature directly. The links below open PubMed queries for each compound.
Frequently Asked Questions
Common Questions
View pricing or inquire wholesale
Semax and Selank are available in 5mg and 10mg vials. Licensed practitioners and research institutions can access wholesale pricing through our B2B portal.