Selank comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Updated 2026-04-23. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide | Tuftsin analogue with a C-terminal Pro-Gly-Pro tail |
| Amino acid sequence | Thr-Lys-Pro-Arg-Pro-Gly-Pro | Abbreviated TKPRPGP in most catalogues |
| Molecular mass | About 752 Da | Value for the free peptide |
| Solubility | Freely soluble in water | Aqueous solutions are kept cold and used promptly |
| Typical storage | -20 °C, dry, protected from light | Applies to the lyophilised powder before reconstitution |
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.
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.
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.
Reverse-phase high-performance liquid chromatography with ultraviolet detection near 214 nanometres is the standard purity method. Mass spectrometry, typically electrospray ionisation, confirms identity through the expected mass-to-charge pattern. Amino acid analysis can verify composition independently. Chiral purity requires separate techniques such as derivatisation followed by chromatographic separation, and such data are rarely reported for research-grade material.
Quantification in biological matrices relies on liquid chromatography coupled to tandem mass spectrometry with stable-isotope internal standards. Low plasma concentrations and adsorption to container surfaces both complicate measurement. Solid-phase extraction is often needed to reduce matrix interference before injection. Reported limits of quantification differ widely between laboratories, which makes direct comparison of pharmacokinetic results difficult and limits meta-analysis.
=== Cultural aspects of exhumation === Frequently, cultures have different sets of exhumation taboos. Occasionally these differences result in conflict, especially in cases where a culture with more lenient exhumation rules wishes to operate on the territory of a different culture. For example, U.S. construction companies have run into conflict with Native American groups that have wanted to preserve their burial grounds from disturbance. In Southern Chinese culture, graves are opened after a period of years. The bones are removed, cleaned, dried, and placed in a ceramic pot for reburial (in Taiwan), or in a smaller coffin and to be reburied in another location (in Vietnam). The practice is called jiǎngǔ(撿骨) in Taiwan, or Bốc mộ(卜墓) in Vietnam "digging up bones" and is an important ritual in the posthumous "care" of children for their deceased parents and ancestors. Jewish law forbids the exhumation of a corpse. The majority of Muslim jurors maintain that an individual buried in a mosque must be exhumed and that offering prayers in such a mosque renders the prayer invalid. Jurists, however, hold that mosques built around already existing graves are to be demolished. In England and Wales once the top of a coffin has been lowered below ground level during a burial, raising the coffin again, for any reason, is considered exhumation regardless of the cause. Even if further work is necessary to properly fit the casket into the grave without further, the Home Office must to be notified and a full investigation undertaken.
Intensive insulin therapy or flexible insulin therapy is a therapeutic regimen for diabetes mellitus treatment. This newer approach contrasts with conventional insulin therapy. Rather than minimize the number of insulin injections per day (a technique which demands a rigid schedule for food and activities), the intensive approach favors flexible meal times with variable carbohydrate as well as flexible physical activities. The trade-off is the increase from 2 or 3 injections per day to 4 or more injections per day, which was considered "intensive" relative to the older approach. In North America in 2004, many endocrinologists prefer the term "flexible insulin therapy" (FIT) to "intensive therapy" and use it to refer to any method of replacing insulin that attempts to mimic the pattern of small continuous basal insulin secretion of a working pancreas combined with larger insulin secretions at mealtimes. The semantic distinction reflects changing treatment.
== E == efficacy – empirical – encephalitis – end-stage disease – endemic – endogenous – endoscopy – endotoxin – endpoint – enteric – enteritis – entry inhibitors – Env – envelope – enzyme – enzyme-linked immunosorbent assay (ELISA) – eosinophil – eosinophilic folliculitis – epidemic – epidemiological surveillance – epidemiology – epithelium – epitope – Epstein-Barr virus (EBV) – erythema – erythema multiforme – erythrocytes – etiology – exogenous – exotoxin – expanded access – experimental drug – expression system
=== Interactions === Any drugs that are also ligands of CYP3A4 and CYP1A2 can potentially increase serum levels and potential for toxicity or decrease serum levels and the efficacy, depending on whether they induce or inhibit the enzymes, respectively. Drugs that may increase the chance of methemoglobinemia should also be considered carefully. Dronedarone and liposomal morphine are both absolutely a contraindication, as they may increase the serum levels, but hundreds of other drugs require monitoring for interaction.
April 30: Start of occupation of Trieste by Yugoslav forces, although challenged by the 2nd New Zealand Division under General Freyberg and the city remained part of Italy. Cox said that it was the first major confrontation of the Cold War and was the one corner of Europe where no demarcation line had been agreed upon in advance by the Allies. May 2: The Italian Civil War ends. May 8: Germany surrenders. End of World War II in Europe (V-E Day). July 24: Potsdam Conference - At the Potsdam Conference, Truman informs Stalin that the United States has nuclear weapons. August 6: Atomic bombings of Hiroshima and Nagasaki - Truman follows the advice of Secretary of War Henry L. Stimson and gives permission for the world's first military use of an atomic weapon, against the Japanese city of Hiroshima. August 8: The USSR honors its agreement to declare war on Japan within three months of the victory in Europe, and invades Manchuria. August 9: With no Japanese response to his ultimatums, Truman gives permission for the world's second and last military use of an atomic weapon, against the Japanese city of Nagasaki (Kokura was the original target). August 12: Japanese forces in Korea surrender to Soviet and American armies. August 17: Proclamation of Indonesian Independence - The Dutch East Indies declares its independence from the Dutch. This marked the beginning of the Indonesian National Revolution.
Sources: en.wikipedia.org
Caterpillar inflation is a method of specimen preservation found in insect collecting, used mostly during the 19th and early 20th century. As a method of preservation it has largely been replaced by freeze drying and preservation in alcohol. In some cases caterpillar inflation offers better colour retention than preservation in alcohol, although the rise of colour photography rendered this less important. A limitation of the technique was that it could produce poor results, in the form of oversized and distended specimens with poor colour, especially if carried out when the caterpillar was moulting or about to undergo pupation. Colour retention was not always perfect and some collectors painted or dyed their inflated specimens although water colours could distort the skin.
===== MeSH D08.811.520.224 – carbon-carbon lyases (EC 4.1) ===== MeSH D08.811.520.224.062 – aldehyde lyases MeSH D08.811.520.224.062.250 – 2-dehydro-3-deoxyphosphoheptonate aldolase MeSH D08.811.520.224.062.400 – fructose-bisphosphate aldolase MeSH D08.811.520.224.125 – carboxy-lyases MeSH D08.811.520.224.125.050 – adenosylmethionine decarboxylase MeSH D08.811.520.224.125.100 – aromatic-L-amino-acid decarboxylase MeSH D08.811.520.224.125.100.500 – dopa decarboxylase MeSH D08.811.520.224.125.250 – glutamate decarboxylase MeSH D08.811.520.224.125.300 – histidine decarboxylase MeSH D08.811.520.224.125.350 – indole-3-glycerol-phosphate synthase MeSH D08.811.520.224.125.387 – methylmalonyl-coa decarboxylase MeSH D08.811.520.224.125.425 – ornithine decarboxylase MeSH D08.811.520.224.125.450 – orotidine-5'-phosphate decarboxylase MeSH D08.811.520.224.125.500 – phosphoenolpyruvate carboxykinase (atp) MeSH D08.811.520.224.125.550 – phosphoenolpyruvate carboxykinase (gtp) MeSH D08.811.520.224.125.650 – phosphoenolpyruvate carboxylase MeSH D08.811.520.224.125.750 – pyruvate decarboxylase MeSH D08.811.520.224.125.800 – ribulose-bisphosphate carboxylase MeSH D08.811.520.224.125.875 – tyrosine decarboxylase MeSH D08.811.520.224.125.900 – uroporphyrinogen decarboxylase MeSH D08.811.520.224.187 – deoxyribodipyrimidine photo-lyase MeSH D08.811.520.224.600 – oxo-acid-lyases MeSH D08.811.520.224.600.200 – anthranilate synthase MeSH D08.811.520.224.600.700 – isocitrate lyase MeSH D08.811.520.224.800 – tryptophanase MeSH D08.811.520.224.900 – tyrosine phenol-lyase
=== Multidisciplinary doctoral programme === Has been instituted for students who have completed masters in any relevant discipline of natural sciences, medicine, engineering and other related sciences. RCB recruits Junior Research Fellowships (JRFs) twice during an academic year and already mentors 31 Research Fellows.
== Influence == Although acquitted, McTavish's case often is mentioned in lectures at medical colleges in Britain and is cited in textbooks and academic papers about forensic science and medical malpractice. Colin Norris, a nurse convicted of four murders and an attempted murder in 2008, is said to have been inspired partly by McTavish's case. He murdered his patients with insulin. Norris, a fellow Scottish nurse, grew up only a mile away from Ruchill where McTavish worked. Her case was discussed extensively in lectures at Dundee University when Norris studied there.
=== Disorders of mineral metabolism === 275 Disorders of mineral metabolism 275.0 Disorders of iron metabolism Aceruloplasminemia Hemochromatosis 275.1 Disorders of copper metabolism Wilson's disease 275.2 Disorders of magnesium metabolism Hypermagnesemia Hypomagnesemia 275.3 Disorders of phosphorus metabolism Familial hypophosphatemia Hypophosphatasia 275.4 Disorders of calcium metabolism 275.41 Hypocalcemia 275.42 Hypercalcemia 275.49 Pseudohypoparathyroidism
Sources: en.wikipedia.org
Selank is a seven-amino-acid peptide built from the tuftsin sequence plus a Pro-Gly-Pro tail. It is produced by chemical synthesis rather than extracted from a natural source. The free peptide is usually supplied as a lyophilised powder or in an aqueous formulation.
Tuftsin is a natural tetrapeptide derived from the Fc portion of immunoglobulin G. Selank retains that tetrapeptide at its N-terminus and adds three residues to improve resistance to enzymatic breakdown. The relationship is structural, and the two molecules are not interchangeable in experimental work.
It holds a product registration in Russia for intranasal use as an anxiolytic. Registrations of that kind are not automatically accepted by regulators elsewhere. In most other countries it is treated as an unapproved substance or a research material.
Selank is a synthetic heptapeptide designed as a stabilized analog of the natural tetrapeptide tuftsin. It has been investigated mainly for anxiolytic and cognitive effects. It is not an approved pharmaceutical in most countries.