Selank 5mg

Selank is a sealed vial with 5mg of freeze-dried peptide. It’s a tuftsin analog peptide. It’s meant for lab and analytical work only.

Selank certificate of analysis

Onyx Research sends Selank to Freedom Diagnostics, a testing lab in the United States, which runs HPLC with UV detection coupled with mass spectrometry. HPLC measures purity and mass spec confirms the molecule’s identity. The report is in the product photos above.

• Selank 5mg: 99.787% purity, reported 1/26/2026, search code Onyx2601230042

The highest result on file is 99.787%. Each report carries a search code, so you can look it up on the Freedom Diagnostics website and check that it matches what’s shown here.

About Selank

Selank is a seven-amino-acid peptide (Thr-Lys-Pro-Arg-Pro-Gly-Pro) based on tuftsin, with a Pro-Gly-Pro tail added. It was developed at the Institute of Molecular Genetics in Moscow.

It’s registered in Russia for anxiety.

Mechanism of action

Selank is based on tuftsin, a short immune peptide cut from antibodies. The Pro-Gly-Pro tail added at the end makes it more stable.

In rat studies it changed the expression of genes tied to GABA signaling and raised BDNF. It’s also studied for effects on the enzymes that break down enkephalins, the body’s own opioid peptides.

Specifications

• Compound: Selank
• CAS number: 129954-34-3
• Molecular formula: C33H57N11O9
• Molecular weight: 751.9 g/mol
• Structure: Thr-Lys-Pro-Arg-Pro-Gly-Pro
• Amount per vial: 5mg
• Form: lyophilized (freeze-dried) powder in a crimp-sealed glass vial
• SKU: ONYX-SELANK-5
• Use: laboratory research only

Research findings

Russian studies report anxiolytic effects in rats and changes in GABA-related gene expression.

A small Russian trial compared it with medazepam in generalized anxiety.

To read the studies yourself, open this PubMed search at the U.S. National Library of Medicine.

How Selank compares

In one line, the peptide is a tuftsin analog studied in GABA signaling and anxiety models. The closest alternatives work differently:

• DSIP is a nine-amino-acid peptide first isolated from sleeping rabbits
• Semax is an ACTH(4-10) analog linked to BDNF in rodent studies

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.

Reconstitution chart

Pick your water volume first and the strength follows from it. With the 5mg vial:

• 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)

Bring the vial up to room temperature and clean the stopper with an alcohol pad. Inject the bacteriostatic water against the glass wall, not onto the powder, and swirl slowly until it’s clear. Shaking whips up foam and can damage the chain.

Storage and stability

Two rules cover the peptide storage: powder in the freezer, solution in the fridge. Keep both away from light and damp, since those break freeze-dried peptides down fastest.

Store mixed vials upright, so the liquid stays off the rubber stopper.

When your order arrives

Each vial carries the black and white Onyx Research label with the compound, the amount, 99% purity and the research-use line. Check that the name and amount match your order and that the cap and crimp are tight.

Freeze-dried powder often shakes loose in transit. Loose powder is no problem if it’s dry. Droplets on the glass or a shrunken, glassy film mean moisture got in, and we’ll want to hear about it.

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.

Related products

• Semax and Selank Blend 10mg: Semax and Selank in one vial
• DSIP 5mg, a neuropeptide
• Semax, an ACTH(4-10) analog
• GLP-2 TZ 10mg (Tirzepatide), a GIP/GLP-1 agonist
• Ipamorelin 10mg, a GH secretagogue

The rest of the range sits in our nootropic peptides. The Onyx Research home page links to all of it.

Questions people ask

How much is in a Selank vial?

5mg, as printed on the label.

What’s the right way to store it?

Keep sealed vials frozen. Once you’ve added water, refrigerate it and plan to finish it within 28 days or so.

Is it for human use?

No. Onyx Research sells it strictly for lab research, never for people or animals.

Is it in stock?

Yes, the peptide is in stock and ready to order.

Is there a crypto discount?

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

Order Selank online

Order Selank now from $40.00. It’s in stock, and shipping is free on every order.

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.