Selank is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Last reviewed on 2026-01-29. Where a claim depends on a specific study, the study is described rather than over-claimed.
Pharmacokinetic data are limited. Like most short peptides, Selank is vulnerable to plasma and tissue peptidases, and its measured half-life in circulation is short, on a minutes scale. The Pro-Gly-Pro tail slows this degradation but does not eliminate it. Intranasal administration is the route described in most reports, with absorption through the nasal mucosa and a hypothesized path into the central nervous system that avoids the blood-brain barrier. Direct measurements of human brain exposure are unavailable, so distribution claims rest on inference from animal work.
Clinical evidence comes mainly from small studies conducted in Russia, several of which were open-label or lacked robust blinding. Reported outcomes include lower anxiety scores, changes in attention measures, and effects on asthenic states following illness. Sample sizes are typically in the tens of participants, and independent replication outside the region is scarce. Reviews published in English generally note the limited methodological quality of the underlying trials. Whether the compound produces clinically meaningful effects under rigorous conditions remains unresolved.
Proposed mechanisms center on modulation of the GABA system, but no single molecular target has been confirmed. Rodent studies report changes in GABA-A receptor expression and in the turnover of serotonin, dopamine, and norepinephrine in several brain regions. Increases in brain-derived neurotrophic factor and its receptor have also been described after repeated administration. These findings come largely from animal models, and the degree to which they describe human neurochemistry remains an open question. The mechanism is best characterized as multi-system and not fully resolved.
Regulatory treatment varies by jurisdiction. In Russia the compound is a registered prescription product, while in the European Union and the United States it is generally handled as a research chemical without a marketing authorization. Suppliers therefore operate outside pharmaceutical oversight, and buyers rely on supplier documentation for purity and identity claims. Chain of custody and third-party testing are the main verification tools. Analysts note that the absence of a pharmacopoeial monograph for research-grade material limits standardization across vendors.
Purity assessment relies mainly on reverse-phase high-performance liquid chromatography with ultraviolet detection. Because the peptide lacks a strong chromophore, detection often uses backbone absorbance near 214 nm. Identity is confirmed by mass spectrometry, typically electrospray ionization or matrix-assisted laser desorption, comparing the measured mass against the expected value. Amino acid analysis can verify composition after acid hydrolysis. Diastereomer content and residual counterions are reported less often, although both can influence biological assays.
| Property | Value | Notes |
|---|---|---|
| Route studied | Intranasal | Predominant route in published reports |
| Circulation stability | Short, minutes scale | Peptidases cleave it; the tail slows the process |
| Analytical method | RP-HPLC with mass spectrometry | Used for identity and purity assessment |
| Reported outcome domains | Anxiety and cognitive measures | Derived from small, mostly regional trials |
| Regulatory status | Marketed in Russia | Availability outside that market is limited |
Regulatory status differs sharply by region. Selank holds a Russian marketing authorization, where it is supplied mainly as nasal drops, while authorities elsewhere have not approved it for medical use. Material sold internationally is therefore usually labeled as a research chemical rather than a medicine. Peer-reviewed publications come predominantly from Russian laboratories, and sample sizes are generally small. Whether the compound produces comparable effects under independent, well-controlled replication remains an open question that the broader literature has not settled.
Selank is a synthetic heptapeptide developed in Russia as a structural analogue of tuftsin, a naturally occurring immunomodulatory tetrapeptide. Its sequence, Thr-Lys-Pro-Arg-Pro-Gly-Pro, keeps the tuftsin core at the N-terminus and appends a Pro-Gly-Pro tail. Researchers at the Institute of Molecular Genetics in Moscow synthesized the compound during the 1990s while searching for peptides with combined anxiolytic and immunomodulatory activity. The added tail was intended to resist enzymatic cleavage and prolong the molecule's presence in circulation.
Naming conventions place Selank in the same research family as Semax, another Russian-developed peptide investigated for cognitive effects. The two compounds share a lineage but differ in sequence and in the biological systems proposed as their targets. Semax descends from ACTH fragments, whereas Selank descends from tuftsin. Publications sometimes identify Selank by its full peptide sequence or by laboratory codes rather than one uniform trade name. Because replication outside Russia is limited, reports on its properties are best read alongside the study design and the purity of the material tested.
Selank is a synthetic heptapeptide developed in Russia during the 1990s. Researchers at the Institute of Molecular Genetics of the Russian Academy of Sciences designed it as a stabilized analog of tuftsin, a naturally occurring immunomodulatory tetrapeptide. The compound has been studied primarily for its reported anxiolytic and nootropic effects. It remains largely unknown in Western pharmacology and is not approved as a medicine by major regulators such as the FDA or the EMA.
The primary structure of Selank is Thr-Lys-Pro-Arg-Pro-Gly-Pro, corresponding to the molecular formula C33H57N11O9 and a monoisotopic mass of roughly 751.9 daltons. The N-terminal threonine and the arginine residue in the fourth position are shared with tuftsin, which carries the sequence Thr-Lys-Pro-Arg. The three additional residues at the C-terminus, Pro-Gly-Pro, extend the chain and are associated with greater resistance to enzymatic degradation. This extension also separates Selank from the shorter parent peptide.
Reported pharmacological effects center on reduced anxiety-like behavior in animal models and on measures of memory and learning. Proposed contributing mechanisms include modulation of GABAergic signaling, shifts in monoamine turnover, and changes in the activity of enzymes that degrade neuropeptides. Effects on the expression of genes linked to neuroplasticity have also been described. No single molecular target is widely accepted, and whether the behavioral findings arise from one pathway or several remains an open question.
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro. It was designed as a stabilized analogue of tuftsin, a naturally occurring tetrapeptide fragment derived from the immunoglobulin heavy chain. The additional Pro-Gly-Pro segment at the carboxyl terminus is intended to slow enzymatic cleavage. The compound is usually described in the literature as a synthetic peptide with anxiolytic and cognitive-related activity, a label that reflects a research context rather than an approved therapeutic category.
Most published work on selank originates from a small number of research groups in the Russian Federation. A large share of that record appears in Russian-language journals, which limits access for readers who rely on English-indexed databases. Independent replication by laboratories outside the original research network is sparse in publicly available sources. This concentration of origin and language is a frequently noted feature when the compound is summarized in broader reviews of synthetic peptides.
Development took place at the Institute of Molecular Genetics of the Russian Academy of Sciences, where a series of short peptides were designed in the 1980s and 1990s. Selank was selected from variants of tuftsin that showed resistance to plasma peptidases. Russian regulatory approval covers it as an anxiolytic agent given intranasally. Outside that market the compound is normally handled as a research chemical rather than a medicine, and no widely recognised international pharmacopoeial monograph exists. The name Selank is a coined trade designation rather than a systematic chemical name.
Enzymatic stability motivates the extra three residues at the carboxyl end. Native tuftsin is cleaved quickly by circulating aminopeptidases and carboxypeptidases, which limits its duration of action and its usefulness as a tool compound. Extending the chain with proline-rich segments is a common design tactic because proline constrains the backbone and slows proteolysis. The same Pro-Gly-Pro motif appears in other Russian-developed peptides of the era. Whether the full seven-residue chain is required for activity, or whether it acts mainly as a prodrug releasing tuftsin, remains unresolved.
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro. Its four N-terminal residues reproduce tuftsin, a tetrapeptide fragment of the immunoglobulin heavy chain, while the C-terminal Pro-Gly-Pro extension is a synthetic addition. The peptide has a molecular mass near 752 daltons and carries a net positive charge at physiological pH because of the arginine and lysine side chains. Published indexes list it under the name Selank and the sequence abbreviation TKPRPGP. Solid-phase peptide synthesis is the standard production route for research quantities.
UV-Vis spectrophotometer: Measures light absorption in UV and visible ranges (200-800 nm). Used for quantification of many inorganic and organic compounds. Infrared spectrophotometer: Measures infrared light absorption, allowing identification of chemical bonds and functional groups. Atomic absorption spectrophotometer (AAS): Uses absorption of light by vaporized analyte atoms to determine concentrations of metals and metalloids. Fluorescence spectrophotometer: Measures intensity of fluorescent light emitted from samples after excitation. Allows highly sensitive analysis of samples with native or induced fluorescence. Colorimeter: Simple spectrophotometers used to measure light absorption for colorimetric assays and tests.
==== Depression ==== Clinical trials, including both open-label trials and double-blind randomized controlled trials (RCTs), have found that single doses of psilocybin produce rapid and long-lasting antidepressant effects outperforming placebo in people with major depressive disorder and treatment-resistant depression. Psilocybin's antidepressant effects with psychological support have been found to last at least six weeks after a single dose. The antidepressant effect size of psilocybin over escitalopram may be small. Only "high-dose" psilocybin (≥20 mg) outperforms escitalopram in improving depressive symptoms. Psilocybin has a moderate to large effect size advantage relative to placebo. Psychedelic-assisted therapy in general (with the vast majority of RCTs studying psilocybin) may be no more effective than open-label traditional antidepressants for major depression; blinding affects antidepressant outcomes but not psychedelics. Functional unblinding by their psychoactive effects and positive psychological expectancy effects (i.e., the placebo effect) are major limitations and sources of bias of clinical trials of psilocybin and other psychedelics for treatment of depression. Relatedly, most of the therapeutic benefit of conventional antidepressants, such as SSRIs, appears to be attributable to the placebo response. It has been proposed that psychedelics like psilocybin may in fact act as active "super placebos" when used for therapeutic purposes.
== Conjugated zwitterions == Strongly polarized conjugated compounds (conjugated zwitterions) are typically very reactive, share diradical character, activate strong bonds and small molecules, and serve as transient intermediates in catalysis. Donor-acceptor entities are of vast use in photochemistry (photoinduced electron transfer), organic electronics, switching and sensing.
== External links == Geroprotectors: Database of geroprotectors For Youth: The Skin - Marine Collagen Peptides Aging Chart Archived 2014-12-16 at the Wayback Machine: A collection of knowledge related to aging
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Sources: en.wikipedia.org
Autism: Oxytocin may play a role in autism and may be an effective treatment for autism's repetitive and affiliative behaviors. Relationship counseling: The use of oxytocin in relationship counseling for well-being has been suggested. Post-traumatic stress disorder: It has been suggested that oxytocin may be a safer option than MDMA for the treatment of PTSD, although oxytocin has less evidence of efficacy.
hybrid The offspring that results from combining the qualities of two organisms of different genera, species, breeds, or varieties through sexual reproduction. Hybrids may occur naturally or artificially, as during selective breeding of domesticated animals and plants. Reproductive barriers typically prevent hybridization between distantly related organisms, or at least ensure that hybrid offspring are sterile, but fertile hybrids may result in speciation.
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Vanilla planifolia is a species of vanilla orchid native to Mexico, Central America, Colombia, and Brazil. It is one of the primary sources for vanilla flavouring, due to its high vanillin content. Common names include flat-leaved vanilla and West Indian vanilla (which is also used for the Pompona vanilla, V. pompona), though it is often simply referred to as vanilla. It was first scientifically named in 1808. Vanilla planifolia played a large role in the early rural economy throughout Mexico and by the 20th century had become a widely cultivated crop across the world. With the species' population in decline and its habitats being converted to other purposes, the IUCN has assessed Vanilla planifolia as Endangered.
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Sources: en.wikipedia.org
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An ion trap consists of electrodes that produce electric fields to trap ions (charged particles), which may be atoms, molecules, or large particles such as dust. Ion traps have a number of applications including mass spectrometry, atomic frequency standards, and quantum computing. In comparison to neutral atom traps, ion traps have deeper trapping potentials (up to several electronvolts) that are agnostic to the internal structure of the ions. The two most popular ion traps are the Paul trap which uses static and oscillating electric fields and the Penning trap, which uses a static electric field and static magnetic field. Paul traps are used in trapped ion quantum computers and realizing atomic clocks, including the most precise instrument humankind has ever made. Penning traps are powerful tools for mass spectrometry and measuring magnetic dipole moments.
== History == The brewery started as a small, casual pub in the alleyways of Gyeongnidan in Seoul. The idea to start the pub was inspired by Tudor's article in The Economist, which claimed: "brewing remains just about the only useful activity at which North Korea beats the South." The pub began selling Bill's Pale Ale, The Booth's first brew, along with a small selection of pizza. After realizing how crucial the cold chain transportation system was to maintaining the quality and flavor of beer, the owners established the first cold chain import and distribution system, The Booth Cold Chain. This was soon importing beers from Mikkeller, Evil Twin, To Øl, and 8 Wired. Two crowdfunding campaigns titled Equity for Booth were launched, in September 2015 and February 2017.
Sources: en.wikipedia.org
Reports describe effects on GABA-A receptor expression, monoamine turnover, and neurotrophic factor levels. These are proposed mechanisms drawn mainly from animal models. No single molecular target has been established.
Intranasal delivery is the route described in most published work. It is used because the peptide is degraded quickly once it reaches circulation. Direct evidence of brain penetration in humans is lacking.
Most trials are small, regionally concentrated, and often lack rigorous blinding or placebo control. Independent replication is limited. Reviews in English generally rate the evidence as preliminary.
Purity is usually reported as an HPLC area percentage, most often measured at 214 nm. Identity is confirmed separately by mass spectrometry. A certificate of analysis should state both the method and the observed value.