Selank Background And Chemical Identity — Complete Guide

By Editorial Desk · published 2026-06-16 · last reviewed 2026-08-01 · Data

heptapeptide raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.

This page was last updated on 2026-08-01 and is reviewed periodically as new material appears.

Selank Background And Chemical Identity

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.

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.

Identity and Structural Background

Naming for this compound is not fully standardised in English sources. The spelling Selanc appears in some transliterations, and catalogue entries may instead list the peptide sequence itself as the identifier. Reference material sometimes groups it with other short synthetic peptides studied for behavioural effects, which can create confusion when citations are compared. Distinguishing the exact sequence from related tuftsin analogues is therefore a practical first step when reviewing any dataset or specification sheet.

Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro, frequently abbreviated as TKPRPGP. It was designed as a structural analogue of tuftsin, a naturally occurring tetrapeptide released by enzymatic cleavage of the immunoglobulin heavy chain. The two additional proline residues at the C-terminal end extend the parent chain and change how the molecule behaves in solution. The free peptide has a calculated molecular mass of approximately 751.9 g/mol and is generally supplied as a lyophilised white to off-white powder.

Development work on the compound began in the 1980s and 1990s at the Institute of Molecular Genetics in Moscow, within the same research programme that produced the peptide Semax. Early investigators sought a tuftsin derivative with improved resistance to enzymatic breakdown and with activity in the central nervous system after peripheral administration. Most of the primary literature from this period was published in Russian, a factor that still shapes how easily the findings can be checked by outside groups.

Selank at a glance

Mechanism and Evidence Status

Pharmacokinetic data are sparse and largely derived from animal work. After intranasal administration the peptide appears in plasma within minutes, and reported half-lives are short, on the order of minutes to tens of minutes. Degradation proceeds through ordinary proteolytic cleavage into constituent amino acids and smaller fragments. Direct evidence that intact Selank reaches brain tissue in meaningful amounts is limited, and the extent of blood-brain barrier penetration is debated. Some authors argue that fragments, not the parent peptide, carry much of the observed activity.

Published clinical work is concentrated in Russian-language journals and generally involves small samples without independent replication. Systematic reviews in English note the shortage of randomised, placebo-controlled trials and the difficulty of verifying methods from translated reports. Outcome measures vary between studies, which complicates pooling of results. Interest in the compound as a cognitive or anxiolytic agent therefore rests on a thinner evidence base than the volume of citations suggests. Replication in well-powered trials with preregistered endpoints would be needed before firm conclusions about efficacy can be drawn.

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Peptide Identity and Structure

Selank is not a naturally occurring peptide and has no known endogenous counterpart in human physiology. Russian-language sources frequently call it TP-7, while English-language sources use the name Selank almost exclusively. Database indexing is uneven, partly because early reports appeared in regional journals that are not widely cataloged. Some summaries describe the material as a tuftsin analog and others as a synthetic heptapeptide; the labels overlap rather than conflict. Citing the primary sequence resolves ambiguity more reliably than the research or trade name alone.

Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro, written TKPRPGP in one-letter notation. Its structure consists of the immunomodulatory tetrapeptide tuftsin, Thr-Lys-Pro-Arg, extended at the carboxyl terminus by a Pro-Gly-Pro segment. The molecular formula is commonly given as C33H57N11O9, corresponding to a monoisotopic mass near 751.4 Da and an average molecular mass near 751.9 Da. All seven residues are proteinogenic amino acids, and the molecule carries no modified side chains or non-natural linkages.

Reference notes

Quantitative characters are morphological features that can be counted or measured for example a plant species has flower petals 10–12 mm wide. Qualitative characters are morphological features such as leaf shape, flower color or pubescence. Both kinds of characters can be very useful for the identification of plants.

=== Other GLUT proteins === There are 14 total GLUT proteins separated into 3 classes based on sequence similarities. Class 1 consists of GLUT 1-4 and 14, class 2 contains GLUT 5, 7, 9 and 11, and class 3 has GLUT 6, 8, 10, 12 and 13. Although there are some sequence differences between all GLUT proteins, they all have some basic structural components. For example, both the N and C termini in GLUT proteins are exposed to the cytoplasm of the cell, and they all have 12 transmembrane segments.

== Procedure == An aqueous sample is treated with an equal volume of 1% strong base (sodium or potassium hydroxide) followed by a few drops of aqueous copper(II) sulfate. If the solution turns purple, it contains protein. 5–160 mg/mL can be determined. Peptides with the correct length of at least 3 amino acids are necessary for a significant, measurable colour shift with these reagents.

In 1982, founder Arch "Beaver" Aplin was a partner in the opening of a store in Clute, Texas, the first to bear the name "Buc-ee's". He formed the name Buc-ee's by combining his childhood nickname and the name of his Labrador Retriever, Buck; as well as the appeal of Ipana toothpaste's animated mascot, Bucky the beaver. Aplin was born in Southeast Texas. His father was born in Harrisonburg, northeast of Alexandria, Louisiana, where Arch's grandparents still lived as of 2019. Buc-ee's eventually expanded and opened its first travel center in Luling in 2003. In 2012, Buc-ee's opened its largest travel center in New Braunfels, Texas, on Interstate 35. The New Braunfels location was the largest convenience store in the world at 68,000 square feet (6,300 m2), but on June 26, 2023, the Sevierville, Tennessee, Buc-ee's opened, becoming the world's largest convenience store at 74,707 square feet (6,940.5 m2). The Sevierville store was narrowly surpassed in size by a new store in Luling, Texas, at 75,000 square feet (7,000 m2) on June 10, 2024, replacing the original Luling travel center, which was 35,000 square feet (3,300 m2). The New Braunfels location had the 2012 "Best Restroom in America" as named by Cintas. After significant expansion in the Greater Houston area and central Texas, the first Buc-ee's in the Dallas–Fort Worth metroplex opened in Terrell, Texas, on June 22, 2015. The travel center is three miles (4.8 km) west of the Shops at Terrell, a former Tanger Outlets center, on Interstate 20.

On November 3, 2017, 31-year-old Geoffrey Howe, the prison's maintenance mechanic, died at Sentara Norfolk General Hospital, and was thus the fourth and final victim to die in this case. Autopsy reports revealed that all the four deceased victims suffered from multiple stab wounds and blunt force injuries. Smith was reportedly stabbed 67 times (including 45 stab wounds to his body) and sustained a total of 32 blunt force injuries to his head and neck. Shannon died from an anoxic brain injury caused by the blunt force trauma to her head. Howe himself died due to extensive brain and skull injuries, and also lost his left eye due to the brutality of the attack. Darden, who died due to a fatal slicing wound on her neck, also had 13 blunt force injuries to her head.

Sources: en.wikipedia.org

Reference notes

== Limitations == Despite its widespread use, the mdx mouse has several important limitations as a model for Duchenne muscular dystrophy. The mdx mouse displays a considerably milder phenotype than human DMD patients, largely due to the compensatory upregulation of utrophin. In 2016, despite decades of successful preclinical studies in mdx mice, many promising therapies failed in human clinical trials, highlighting the translational gap between the mouse model and human disease. To overcome these limitations, researchers have developed improved models such as the mdx/utrophin double knockout mouse, which more closely resembles the severe human DMD phenotype, and humanized mdx models that allow testing of human-specific therapies such as exon skipping drugs.

== Stage credits == Twelfth Night – 2002 Nero (Another Golden Rome) – 2006 (San Francisco) Spring Awakening – 2006 The Nightingale – 2003, 2005 (workshop) 2006 (based on The Nightingale) Whisper House – 2010 (Old Globe Theatre, San Diego) Carson McCullers Talks About Love (with Suzanne Vega) – 2011 (Off-Broadway) Alice by Heart – 2012 Because of Winn-Dixie – 2013 American Psycho – 2013 Noir – 2015 The Taming of the Shrew – 2016 (Washington, DC) The Secret Life of Bees – 2019 (Atlantic Theater Company, New York), 2023 (Almeida Theatre, London) Memoirs of Amorous Gentlemen – 2026

=== Intact molecular isotope ratio mass spectrometry === Conventionally, mass spectrometry, such as gas chromatography-mass spectrometry (GC-MS) and gas chromatography -time of flight(GC-TOF), is a common technique for analyzing isotopically labeled molecules. This method involves ionizing and analyzing isotopologues of an intact organic molecule of interest rather than its products of pyrolysis or conversion. However, it does not work for natural abundance hydrogen isotopes because conventional mass spectrometers do not have enough mass-resolving power to measure the 13C/D isotopologues of intact organic molecules or molecular fragments at natural abundance. For example, to resolve the single D substituted isotopologue peak of any hydrocarbons one will have to be able to at least exclude single 13C substituted isotopologue peak, which sits at the same cardinal mass yet 0.0029 Da lighter and is of orders of magnitude more abundant. Recent advances in analytical instruments enable direct measurement of natural abundance DHRs in organic molecules. The new instruments have the same framework as any conventional gas source IRMS, but incorporate new features such as larger magnetic sector, double focusing sectors, quadrupole mass filter and multi-collectors. Two commercial examples are the Nu Panorama and the Thermo Scientific 253 Ultra. These instruments generally have good sensitivity and precision. Using only tens of nanomoles of methane, the Ultra can achieve a stable high precision of ~0.1‰ error in δD.

Simultaneously, the government tried a direct negotiation with the ETA leadership but the "Algiers talks" did not lead to any result; on the contrary, the group perpetrated some of the bloodiest attacks in its history: the Hipercor bombing, in Barcelona, and the Zaragoza barracks bombing. The government then sought to reach a great "anti-terrorist" pact that would also include democratic Basque nationalism, which was finally achieved with the signing of the Ajuria Enea Pact in January 1988. A few months later, two policemen, José Amedo and Michel Domínguez were arrested, accused of being involved in the kidnapping of Segundo Marey among other crimes committed by the GAL, and with the aggravating circumstance that they had counted on the reserved funds of the Ministry of the Interior to carry out the attacks. The knowledge of this fact forced the Minister of the Interior José Barrionuevo to resign and he was replaced by José Luis Corcuera. The consolidation of the democratic system included the development of the rights and freedoms recognized in the Constitution of 1978.

Sources: en.wikipedia.org

Reference notes

A biomolecule or biological molecule is loosely defined as a molecule produced by a living organism and essential to one or more typically biological processes. Biomolecules include large macromolecules such as proteins, carbohydrates, lipids, and nucleic acids, as well as small molecules such as vitamins and hormones. A general name for this class of material is biological materials. Biomolecules are an important element of living organisms. They are often endogenous, i.e. produced within the organism, but organisms usually also need exogenous biomolecules, for example certain nutrients, to survive. Biomolecules and their reactions are studied in biology and its subfields of biochemistry and molecular biology. Most biomolecules are organic compounds, and just four elements—oxygen, carbon, hydrogen, and nitrogen—make up 96% of the human body's mass. But many other elements, such as the various biometals, are also present in small amounts. The uniformity of both specific types of molecules (the biomolecules) and of certain metabolic pathways are invariant features among the wide diversity of life forms; thus these biomolecules and metabolic pathways are referred to as "biochemical universals" or "theory of material unity of the living beings", a unifying concept in biology, along with cell theory and evolution theory.

=== Vascular smooth muscle cells === Vascular smooth muscle cells play a crucial role in atherogenesis and were historically considered to be beneficial for plaque stability by forming a protective fibrous cap and synthesizing strength-giving extracellular matrix components. However, in addition to the fibrous cap, vascular smooth muscle cells also give rise to many of the cell types found within the plaque core and can modulate their phenotype to both promote and reduce plaque stability. Vascular smooth muscle cells exhibit pronounced plasticity within atherosclerotic plaque and can modify their gene expression profile to resemble various other cell types, including macrophages, myofibroblasts, mesenchymal stem cells and osteochondrocytes. Importantly, genetic lineage-tracing experiments have unequivocally shown that 40-90% of plaque-resident cells are vascular smooth muscle cell-derived, therefore, it is important to research the role of vascular smooth muscle cells in atherosclerosis to identify new therapeutic targets.

=== Works cited === Brand, Chad; Mitchell, Eric (2015). Holman Illustrated Bible Dictionary. B&H Publishing Group. ISBN 978-0-8054-9935-3. Cross, Frank Moore (1973). Canaanite Myth and Hebrew Epic. Cambridge, Massachusetts: Harvard University Press. ISBN 978-0-674-09176-4. LCCN 72076564. OCLC 185400934. Dever, William (2003). Who Were the Early Israelites and Where Did They Come From?. Eerdmans. ISBN 978-0-8028-0975-9. Archived from the original on 1 July 2023. Retrieved 14 August 2015. Dever, William G. (2005). Did God Have a Wife?: Archaeology and Folk Religion in Ancient Israel. Wm. B. Eerdmans. ISBN 978-0-8028-2852-1. Retrieved 7 February 2016. Faust, Avraham (2015). "The Emergence of Iron Age Israel: On Origins and Habitus". In Levy, Thomas E.; Schneider, Thomas; Propp, William H. C. (eds.). Israel's Exodus in Transdisciplinary Perspective: Text, Archaeology, Culture, and Geoscience. Springer. pp. 467–482. ISBN 978-3-319-04768-3. Archived from the original on 21 October 2021. Retrieved 31 March 2023. Goldenberg, David M. (11 April 2009). The Curse of Ham: Race and Slavery in Early Judaism, Christianity, and Islam. Princeton University Press. pp. 90–91. ISBN 978-1-4008-2854-8. OCLC 1162398032. Grabbe, Lester L. (2004). A History of the Jews and Judaism in the Second Temple Period. T&T Clark International. ISBN 978-0-567-04352-8. Archived from the original on 1 July 2023. Retrieved 14 August 2015. Grabbe, Lester L., ed. (2008). Israel in Transition: From Late Bronze II to Iron IIa (c. 1250–850 B.C.E.). T&T Clark International. ISBN 978-0-567-02726-9.

==== Slovakia ==== On 1 March 2021, Slovakia bought 2 million doses of the Sputnik V vaccine. Slovakia received the first batch of 200,000, and expected to receive another 800,000 doses in March and April. Another 1 million doses were set to arrive in May and June. On 8 April, Slovakia's drug regulator said that the Sputnik V vaccine it received did "not have the same characteristics and properties" as the version endorsed by The Lancet. The Slovak State Institute for Drug Control stated that Sputnik V has not yet been approved for use, as the first 200,000 doses received on 31 March were different from the product currently being reviewed by the European Medicines Agency as well as from the vaccine used in studies published in The Lancet. The producers have failed to reply to requests for documentation, and approximately 80% of the data was not supplied even after repeated requests. Due to the inconsistencies, it was not possible to review the safety and efficacy of the vaccine. The Russian Direct Investment Fund replied that the Slovak laboratory which tested the vaccine was not certified by the EMA. Slovak Prime Minister Igor Matovič resigned on 30 March, due to the political crisis started by the order of the Sputnik V vaccine. On 6 April 2021, the RDIF asked to return the delivered first batch of the vaccine due to "multiple contract violations". On 29 April 2021, the Slovak Ministry of Health published the Sputnik V contract.

== Further reading == Huang, T. C.; Teng, D. F. (2004). "Soy Sauce". Handbook of Food and Beverage Fermentation Technology. doi:10.1201/9780203913550.ch29 (inactive 12 July 2025). ISBN 978-0-8247-4780-0.{{cite book}}: CS1 maint: DOI inactive as of July 2025 (link)—on the production of soy sauce

Sources: en.wikipedia.org

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