Selank

Selank is a synthetic peptide, a short chain of seven amino acids, engineered from tuftsin, a naturally occurring fragment of the antibody immunoglobulin G. Compared with natural tuftsin, Selank carries added amino acids at one end that are intended to slow enzymatic breakdown, giving it greater stability in solution and in laboratory assay conditions.

In the scientific literature, it is categorized as a nootropic-class and anxiolytic-class research peptide, most often discussed alongside studies of GABAergic signaling, stress-response pathways, and cognitive-function models. It is not a hormone, a growth factor, or a weight-management compound, and it is structurally unrelated to compounds like BPC-157 or GLP-1 analogs. Because of these structural changes, reference sources typically list it as a stabilized tuftsin analog rather than as tuftsin itself.

Quick facts

• Class: synthetic heptapeptide, a stabilized tuftsin analog
• Amino acid sequence length: 7 residues
• Parent molecule: tuftsin (an immunoglobulin G fragment)
• Typical supplied form: lyophilized powder intended for laboratory reconstitution
• Research categories: cognition, stress response, GABA-system signaling
• Regulatory note: not evaluated or approved by the FDA for any use

In short, Selank is a lab-grade research peptide built from a modified tuftsin backbone. It exists solely as a subject of scientific study, not as a consumer or clinical product, and it is supplied and referenced here strictly for research and educational purposes, never for human or animal use.

All of our reusable peptide pens (V1, V2, V3 and Gansulin) are compared on one page.

Selank is supplied as a lyophilized powder in a standard 3 ml glass cartridge, intended strictly for laboratory research and hands-on handling practice - not for human or animal use.

Cartridge and Hardware Compatibility

Our pens take standard 3 ml (300-unit) glass cartridges with the 11 mm long plunger (stopper), the cartridge we sell. 3 ml cartridges are also made with a shorter, about 8 mm plunger, and a pen is built for one height, so check that a cartridge from another source has the 11 mm long plunger before loading it; the glass looks identical from the outside. Pen needles are a separate, universal component: any screw-on needle rated 28G-33G threads onto a standard pen fitting, independent of cartridge stopper length.

Reconstitution Workflow Notes

When practicing reconstitution technique, add diluent slowly down the interior vial wall rather than onto the lyophilized cake, and swirl gently rather than shaking to limit mechanical stress on the powder. Follow your reconstitution kit's documentation for storage guidance after mixing.

What it is

Selank is a synthetic peptide built from seven amino acids (the building blocks of proteins), with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro. It is a structural analog of tuftsin, a naturally occurring peptide fragment of the immune protein immunoglobulin G (IgG).

• Origin: derived from tuftsin by extending the amino acid chain.
• Purpose of the change: the added amino acids slow enzymatic breakdown, similar to adding links so a chain holds together longer.
• Result: greater metabolic stability - resistance to degradation - relative to native tuftsin, a common reference point in structure-activity comparisons of tuftsin-derived analogs.

This overview describes Selank's composition and origin as a reference point for laboratory documentation only.

Research context and categorization

Selank is a synthetic heptapeptide derived from tuftsin, an endogenous tetrapeptide known for its role in immune regulation. Because of that shared origin, published literature places Selank in two overlapping research categories: peptides studied for possible effects on cognition and mood, and peptides studied for possible immunomodulatory activity — meaning effects on how the immune system communicates internally and responds to signals.

It was originally developed at the Institute of Molecular Genetics of the Russian Academy of Sciences, working in collaboration with the V.V. Zakusov Research Institute of Pharmacology.

Research categories

• Neurobehavioral research: examines possible interaction with the GABAergic system, where GABA moderates nerve activity, and the monoaminergic system, covering dopamine, serotonin, and related signaling pathways. This category is most often discussed alongside anxiety, stress, and attention research.
• Immune-signaling research: tracks changes in cytokines and interleukins, small proteins that carry immune-system signals — a line of inquiry connected directly to Selank's tuftsin origin.

Approval and evidence limitations

• Outside Russia, these research areas remain under active investigation rather than established science.
• In the United States and most other countries, none of these research areas are confirmed or approved for use.
• The majority of published data on Selank originates from Russian research institutions.
• Independent replication by research groups elsewhere remains limited, so current findings should be treated as preliminary rather than confirmed.

Status

• Regulatory status: Selank is not FDA-approved in the United States and has no approved human or veterinary use there; it is a research compound, not for consumption, and PreppinPeppers does not sell it. As of 2026, the FDA lists it as a Category 2 bulk drug substance, meaning outsourcing facilities and compounding pharmacies (specialized pharmacies that mix custom preparations) may not use it while the FDA's review remains open. Separately, Selank is approved in Russia and neighboring countries as a prescription or over-the-counter product; that approval has no bearing on its unapproved, research-only status in the US.
• Sport status: Selank does not appear by name on the WADA Prohibited List (WADA: the World Anti-Doping Agency). Because it lacks approval from major Western regulators for therapeutic use, it may still fall under the S0 Non-Approved Substances category, a catch-all covering unapproved substances generally. Anyone subject to anti-doping testing should treat this as a caution flag, not a clearance.

Key point: Selank is not FDA-approved in the United States. It remains restricted to research use only and is classified as a Category 2 bulk drug substance.

Reconstitution notes (general)

Lyophilized peptides come as a freeze-dried powder in a vial. To prepare them for research, you add bacteriostatic water, a sterile water containing a small amount of preservative (typically benzyl alcohol). Concentration means how much peptide is in each milliliter of liquid, found by dividing the milligrams in the vial by the milliliters of water added. Common examples:

• 5 mg in 2 mL gives 2.5 mg/mL
• 10 mg in 2 mL gives 5 mg/mL

You can work out volumes and concentrations with the calculator at peptide calculator.

Preservatives such as benzyl alcohol can affect some peptides' stability over time, so reconstituted vials are generally treated as short-term research solutions rather than indefinite stock.

A visible colour shift can also flag that a solution has changed: in copper-binding peptides like GHK-Cu, the blue tint comes from the bound copper ion, and a shift toward colourless usually means the copper has separated from the peptide backbone - a sign the sample's chemistry is no longer intact, not a quality benchmark on its own.

Dilution and handling notes (compound-specific)

Selank is a short peptide that dissolves easily in water. Reference concentrations commonly cited in the literature fall in the range of about 1 to 5 mg/mL.

Reconstitution Ratios

• 5 mg vial: Diluted with 2 to 3 mL of bacteriostatic water, yielding roughly 2.5 mg/mL down to about 1.67 mg/mL.
• 10 mg vial: Diluted with 2 to 3 mL of bacteriostatic water, yielding roughly 5 mg/mL down to about 3.33 mg/mL.

Lower concentrations can make small volumes easier to read during evaluations.

Mixing Best Practices

Selank dissolves readily and rarely clumps or gels, though it can foam if water is added too quickly. Add bacteriostatic water slowly down the inside vial wall rather than onto the powder, then swirl or gently roll it. Do not shake it: shaking pulls in air, creating foam that can stress the peptide. The finished solution should be clear and colorless.

Does Benzyl Alcohol Affect Stability in Solution?

A common question is whether the benzyl alcohol preservative in bacteriostatic water affects peptide stability once mixed. At reconstitution concentrations, benzyl alcohol is chemically stable; reference material points more to storage time, temperature, and freeze-thaw cycling as degradation factors, which is why refrigeration and a defined use window are commonly noted in handling guides.

Note that in its Russian clinical literature, Selank is documented as an intranasal spray rather than an injectable form; the notes above apply to solution-based research formats only.

Handling and storage

Store reconstituted Selank in a refrigerator at 2 to 8°C, away from direct light. Before each draw, wipe the stopper with a fresh alcohol swab and attach a new pen needle — our pens accept universal 28G-33G screw-on needles. Label the vial with the reconstitution date so the usable window is easy to track.

A reconstituted solution is generally referenced with about a 4-week usable window when kept refrigerated. This window is a general reference point, not a guarantee, and applies regardless of which diluent was used — bacteriostatic preservatives help control microbial growth in the vial but do not by themselves extend or confirm peptide stability.

Inspect the vial before every draw: discard it if the liquid turns cloudy, changes color, or shows floating particles, as any of these can indicate degradation.

Frequently asked questions