Semax

Onyx Research carries Semax in 5mg, 10mg and 30mg vials. Each holds peptide as dry freeze-dried powder, and Semax is an ACTH(4-10) analog peptide. Onyx Research supplies it for in-vitro research.

This compound also comes as a ready-made nasal spray, picked from the same menu, for labs that want a ready solution. Ask our support team for the concentration before you order it.

Semax purity and COA

Freedom Diagnostics, an independent US lab, tested the peptide for Onyx Research using HPLC-UV for purity and mass spectrometry for identity. The certificate sits in the gallery next to the vial photos.

• Semax 5mg: 99.086% purity, reported 1/26/2026, search code Onyx2601230045

Want to verify it? Each search code above opens the original report on the Freedom Diagnostics site. The best figure on file is 99.086%.

What is Semax?

Semax is a seven-amino-acid peptide (Met-Glu-His-Phe-Pro-Gly-Pro) based on a fragment of ACTH, with a Pro-Gly-Pro tail added for stability. It was developed at the Institute of Molecular Genetics in Moscow.

It’s registered in Russia and used there as a nasal drop.

Mechanism of action

Semax is based on ACTH(4-10), a piece of the stress hormone ACTH that affects the brain but not the adrenal glands. The Pro-Gly-Pro tail slows its breakdown.

In rats it raised BDNF, a growth factor that supports neuron survival and learning, and changed dopamine and serotonin activity. It’s usually studied as an intranasal compound.

Specifications

• Compound: Semax
• CAS number: 80714-61-0
• Molecular formula: C37H51N9O10S
• Molecular weight: 813.9 g/mol
• Structure: Met-Glu-His-Phe-Pro-Gly-Pro
• Sizes: 5mg, 10mg, 30mg
• Other options: Nasal Spray
• Form: lyophilized (freeze-dried) powder in a crimp-sealed glass vial
• SKU: ONYX-SEMAX
• Use: laboratory research only

Published studies

Dolotov and colleagues reported that the peptide raised BDNF and its receptor TrkB in rat hippocampus.

Russian clinical studies looked at stroke recovery.

You can read the original papers through this PubMed search for Semax, a free database from the U.S. National Library of Medicine.

How it compares

Semax is an ACTH(4-10) analog linked to BDNF in rodent studies. Other compounds in the same area take different routes:

• Selank is a tuftsin analog studied in GABA signaling and anxiety models
• DSIP is a nine-amino-acid peptide first isolated from sleeping rabbits

Brain research reaches them by separate routes: BDNF, GABA signaling, sleep regulation, neurotrophic peptide mixtures and potassium channels. Every one of them is in stock in our nootropic peptides.

Checking your vials

The Onyx Research label names the compound and the amount. Compare both with your order confirmation, and check the crimp seal before the vial goes into storage.

Look for a dry powder. Loose pieces are fine. Wet or discolored material should stay out of your work, so contact us with a photo.

Write the arrival date on the box, and add the mixing date and volume later. That short log answers most questions if a result looks odd.

Semax dilution chart

Concentration is simple division: the 5mg in the vial over the volume of water you add. Here’s the 5mg vial at three common volumes:

• Add 1mL: 5mg/mL (500mcg per 0.1mL, or 10 units on a U-100 syringe)
• Add 2mL: 2.5mg/mL (250mcg per 0.1mL, or 10 units on a U-100 syringe)
• Add 3mL: 1.67mg/mL (166.7mcg per 0.1mL, or 10 units on a U-100 syringe)

Use bacteriostatic water, added slowly down the inside of the vial. Swirl, don’t shake. If some powder sticks to the glass, rest the vial in the fridge for a few minutes and swirl again.

Storage and stability

Sealed the peptide lasts longest frozen at -20°C and dark. The fridge is fine for short spells. Mixed solution stays at 2 to 8°C and should be used within roughly 28 days.

Mix one vial at a time. Dry powder keeps for months, but solution only keeps for weeks.

Choosing a Semax option

Pick from 4 options in the option menu. Current prices:

• 5mg: $49.00
• 10mg: $99.00
• 30mg: $160.00
• Nasal Spray: $99.00

The 30mg size works out cheapest per milligram, at about $5.33 per mg against $9.90 for the 10mg. The small vial is the better pick for a pilot run.

Related products

• Semax and Selank Blend 10mg: Semax and Selank in one vial
• DSIP 5mg, a neuropeptide
• Selank 5mg, a tuftsin analog
• Kisspeptin-10 10mg, a neuropeptide
• GLP-3 RT (Retatrutide), a triple agonist

For more options, open our nootropic peptides or head back to the Onyx Research home page.

Questions people ask

How much is in a Semax vial?

5mg, 10mg and 30mg, depending on the size you pick.

Which diluent should I use?

Bacteriostatic water in most cases. Our mixing chart above shows the concentration for 1, 2 or 3mL.

What’s the right way to store it?

Freezer at -20°C while sealed, fridge at 2 to 8°C once mixed. Mixed solution is good for roughly four weeks.

Is it for human use?

No. It’s a research material only, with no approval for human or veterinary use.

Is there a crypto discount?

Yes. Pay with cryptocurrency at checkout and an extra discount comes off your order.

Buy Semax today

Choose your option, add the peptide to your cart for from $49.00. It’s in stock, and Onyx Research ships it free to the US, Canada, Europe, Australia and beyond.

Crypto payments get an extra discount, applied at checkout.

Building a larger order? See what else is in our nootropic peptides.

Research use only. Onyx Research supplies this material to qualified labs for in-vitro work. It’s not a medicine, supplement, food or cosmetic, and it must not be given to people or animals. No statement here has been reviewed by the FDA.