Frequently Asked Questions
15+ expert answers about peptide research, purity standards, handling, and sourcing.
What is Semax?
Semax is a synthetic heptapeptide nootropic based on the ACTH(4-7) fragment, developed and approved in Russia. It enhances BDNF and NGF expression in the brain without affecting cortisol or adrenal function.
How does Semax compare to Selank?
Both are Russian-developed heptapeptides with Pro-Gly-Pro extensions. Semax is based on ACTH(4-7) and is primarily nootropic/neuroprotective, enhancing BDNF expression. Selank is based on tuftsin and is primarily anxiolytic/immunomodulatory, enhancing GABA function. They are complementary.
Does Semax affect cortisol like ACTH?
No. Semax uses only the ACTH(4-7) fragment, which does not bind melanocortin receptors responsible for adrenal stimulation. It has no effect on cortisol levels or adrenal function.
How does Semax work at the molecular level?
Semax is a synthetic heptapeptide based on ACTH(4-7) (the fragment Met-Glu-His-Phe from adrenocorticotropic hormone) with an added Pro-Gly-Pro C-terminal extension for metabolic stability. Developed at the Institute of Molecular Genetics of the Russian Academy of Sciences alongside selank, semax is approved in Russia as a nootropic and neuroprotective medication.
What research areas has Semax been studied in?
Semax has been investigated across 4 primary research areas: Nootropic Research, Neuroprotection, BDNF Expression, Stroke Recovery. Each area has published preclinical data supporting the peptide's activity through distinct but sometimes overlapping molecular pathways.
What are the most significant research findings for Semax?
Levitskaya et al. (2004) demonstrated semax enhances BDNF and TrkB expression in the rat hippocampus and basal forebrain. Additionally, dolotov et al. (2006) showed semax increases NGF and BDNF mRNA levels in the rat brain cortex and hippocampus.
What dosages of Semax are used in published research?
Russian clinical protocols use intranasal doses of 250-500 mcg per day (typically 3 drops of 0.1% solution per nostril). Animal neuroprotection studies use 50-150 mcg/kg. Stroke studies used 12-18 mcg/kg/day intranasally.
How should Semax be stored and handled in the laboratory?
Store lyophilized powder at -20C. Reconstituted solution at 2-8C, use within 14-21 days. The Pro-Gly-Pro extension provides improved stability over native ACTH fragments.
What is the CAS number and molecular weight of Semax?
The CAS registry number for Semax is 80714-61-0. The molecular weight is 813.93 g/mol. The amino acid sequence is: Met-Glu-His-Phe-Pro-Gly-Pro.
What published studies support Semax research?
Key publications include: Semax, an analogue of ACTH(4-10) with cognitive effects, regulates BDNF and trkB expression in the rat hippocampus Among others, there are 3 peer-reviewed publications cited in our research profile, all indexed in PubMed.
What purity level should I look for when sourcing Semax?
Research-grade Semax should be at minimum 98% purity as verified by HPLC analysis. Mass spectrometry should confirm molecular identity. Always request a batch-specific Certificate of Analysis (COA) from an independent third-party laboratory before using any peptide in experiments.
How do I reconstitute Semax for laboratory use?
Add bacteriostatic water slowly down the inside wall of the vial — never spray directly onto the lyophilized powder. Gently swirl until fully dissolved; the solution should be clear and colorless. Calculate your desired concentration based on the peptide mass and volume of solvent added. Use a sterile syringe and swab the vial stopper with alcohol before each withdrawal.
Is Semax approved for human use?
No. Semax is designated Research Use Only (RUO). It is not approved by the FDA for human consumption, veterinary use, or any therapeutic purpose. All references to research findings on this site describe preclinical laboratory studies, not clinical recommendations. Consult a licensed healthcare provider for any medical questions.
How long does reconstituted Semax remain stable?
Once reconstituted, Semax should be stored at 2-8°C (standard refrigerator temperature) and used within 30 days. Lyophilized (unreconstituted) peptide is stable for 12-24 months at -20°C when kept sealed and protected from light. Never refreeze a reconstituted solution, and avoid repeated freeze-thaw cycles.
Where can I source research-grade Semax?
Research-grade Semax with 98%+ purity, HPLC verification, and third-party COAs is available at researchvials.com. All peptides ship from the USA with cold-chain packaging to maintain product integrity. This site is an educational resource and does not sell products directly.
General Peptide Research
What are research peptides?
Research peptides are short chains of amino acids — typically between 2 and 50 residues — synthesized for laboratory investigation. They let researchers study receptor binding kinetics, cellular signaling cascades, and enzyme interactions with high specificity. They are not intended for human use.
What does 98%+ purity actually mean for my experiments?
It means HPLC analysis confirmed that at least 98% of the lyophilized powder is your target peptide. The remaining fraction is typically truncated sequences or deletion peptides from synthesis. This matters because impurities can activate off-target pathways and wreck dose-response curves. Mass spectrometry provides the second check, confirming molecular identity.
How should I store peptides long-term?
Keep lyophilized (freeze-dried) vials at -20°C. They are remarkably stable in this form — 12 to 24 months with no significant degradation. Once you reconstitute with bacteriostatic water, move to 2-8°C and use within 30 days. The cardinal rules: no repeated freeze-thaw cycles, protect from light, sterile technique every time you draw from the vial.
What is third-party testing and why does it matter?
It means a lab with zero financial ties to the manufacturer independently verifies identity, purity, and endotoxin levels. This eliminates the obvious conflict of interest in self-testing. The resulting Certificate of Analysis (COA) gives you hard data about what is actually in the vial — not what someone claims is in it.
How do I properly reconstitute a lyophilized peptide?
Swab the vial stopper with an alcohol wipe. Draw your bacteriostatic water into a sterile syringe. Inject slowly down the inside glass wall of the vial — not directly onto the cake of powder, which can denature it. Let it sit for a minute, then gently swirl. Never shake. The solution should be perfectly clear. If it is cloudy, something went wrong.
What does "Research Use Only" mean in practice?
It means the product exists solely for laboratory research — in vitro cell culture work, preclinical animal studies, and educational purposes. RUO compounds have not gone through FDA approval for human safety or efficacy. They cannot legally be sold as drugs, supplements, food additives, or for veterinary use.
How do I read a Certificate of Analysis (COA)?
Look for four things. First, HPLC purity — should be 98%+ with a clean chromatogram showing one dominant peak. Second, mass spectrometry — the observed molecular weight should match the theoretical weight within instrument precision. Third, appearance — should state white or off-white lyophilized powder. Fourth, endotoxin testing — should be below detection limits for injectable-grade material.
Where can I find published peptide research?
PubMed (pubmed.ncbi.nlm.nih.gov) is the gold standard. Search by peptide name, CAS number, or mechanism. Start with review articles — they synthesize the field so you do not have to read 50 primary papers first. Every PMID we cite on this site links directly to the PubMed entry so you can verify our claims.
Where can I source peptides referenced on this site?
This site is purely educational — we do not sell anything. All research peptides referenced here are available at researchvials.com, with 98%+ purity, third-party COAs, and USA-based cold-chain shipping.