A practical reference on Selank: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2026-06-24 and is reviewed periodically as new material appears.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide | Tuftsin analogue |
| Sequence | Thr-Lys-Pro-Arg-Pro-Gly-Pro | Single-letter form: TKPRPGP |
| Molecular formula | C33H57N11O9 | Calculated for the free peptide |
| Molecular weight | About 751.9 g/mol | Derived from the sequence |
| Appearance | White to off-white powder | Typical lyophilised form |
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.
The compound has a calculated molecular weight near 751.9 daltons and carries a net positive charge at physiological pH because of its arginine residue. It dissolves freely in water and in common aqueous buffers, and typically appears as a white or off-white lyophilized powder. The amide backbone makes the molecule susceptible to peptidases, which limits oral use and favors intranasal or parenteral routes. Nomenclature in the literature varies: the substance is also described by the sequence abbreviation TP-7 and by a Russian trade designation.
Once dissolved, the peptide is markedly less stable than the dry powder. Aqueous solutions are subject to backbone hydrolysis and to microbial growth when they are handled without sterile technique. Buffered solutions near neutral pH are common for short-term laboratory work, while acidic conditions are sometimes used to improve solubility. Analytical laboratories generally prepare working solutions fresh rather than storing them, and a residual water film left in a reopened vial can seed degradation even when the container appears dry.
Reversed-phase high-performance liquid chromatography is the standard technique for estimating peptide purity. The result is a peak-area percentage, which describes how much of the detected material elutes as the main peak in one run. Mass spectrometry confirms the molecular mass and can reveal truncated, adducted, or otherwise modified species. Amino acid analysis or tandem mass spectrometry can address sequence fidelity when identity is in doubt. None of these measurements, taken alone, establishes that a sample is fit for any specific purpose.
Lyophilized selank is normally supplied as a dry powder and is considered stable for extended periods when kept cold and dry. Moisture uptake is the main practical threat, because absorbed water promotes both hydrolysis and aggregation in the solid state. Vials are usually warmed to room temperature before opening so that condensation does not form on the powder. Supplier documentation commonly specifies -20 °C for routine storage, with -80 °C used for material intended to be archived for years.
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.
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.
Lyophilised material kept dry at minus 20 degrees Celsius or colder is the most stable form, and suppliers commonly state a shelf life of two years or more under those conditions. Once dissolved, degradation accelerates through hydrolysis and deamidation, particularly at alkaline pH or elevated temperature. Working solutions are usually divided into single-use aliquots to avoid repeated freeze-thaw cycles. The choice of reconstitution solvent affects both stability and the ionic strength of the final preparation.
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.
=== Migration of can components === In canning toxicology, migration is the movement of substances from the can itself into the contents. One toxic substance that can migrate is lead, which causes lead poisoning, but has been phased out of usage in cans since the 20th century. A newer concern is bisphenol A (BPA), a potential endocrine disruptor that is an ingredient in the epoxy commonly used to coat the inner surface of cans. Some cans are manufactured with a BPA-free enamel lining produced from plant oils and resins. In February 2018, the Can Manufacturers Institute, a trade association in the United States, surveyed the industry and reported that at least 90% of food cans no longer contained BPA.
To Killanin's surprise, a postal ballot of IOC members decided in February that SANOC had made sufficient progress in to be invited to the 1968 Games, on the understanding that its team would be multiracial and remaining discrimination would be ended by the 1972 Games. This verdict prompted the SCSA countries to withdraw; in the US, the American Committee on Africa organised a boycott by African American athletes; the Eastern Bloc also threatened a boycott. The Mexican organising committee was worried that its Games would be a fiasco and asked the IOC to reconsider. Brundage flew to South Africa in an unsuccessful bid to ask it to withdraw voluntarily. The IOC executive board met on 21 April 1968 to seek a diplomatic formula under which to exclude South Africa, finally agreeing that "due to the international climate, the executive committee was of the opinion it would be most unwise for South Africa to participate".
synonymous mutation Also synonymous substitution or samesense mutation. A type of mutation in which the substitution of one nucleotide base for another results, after transcription and translation, in an amino acid sequence which is identical to the original unmutated sequence. This is possible because of the degeneracy of the genetic code, which allows different codons to code for the same amino acid. Though synonymous mutations are often considered silent, this is not always the case; a synonymous mutation may affect the efficiency or accuracy of transcription, splicing, translation, or any other process by which genes are expressed, and thus become effectively non-silent. Contrast nonsynonymous mutation.
== Effect on sleep architecture == In a small study of 14 subjects, ibutamoren dosed at 25 mg/day at bedtime was shown to increase rapid eye movement sleep by 20% and 50% in young and older subjects respectively. Treatment with ibutamoren also resulted in an approximate 50% increase in slow-wave sleep in young subjects.
A remnant of a Green Mountain Boys flag, believed to have belonged to John Stark, is owned by the Bennington Museum. It still exists as one of the few regimental flags from the time of the American Revolution. Although Stark was at the Battle of Bennington and likely flew this flag, the battle has become more commonly associated with the Bennington flag, which is believed to be a 19th-century banner.
Sources: en.wikipedia.org
=== Troponin === In both cardiac and skeletal muscles, muscular force production is controlled primarily by changes in the intracellular calcium concentration. In general, when calcium rises, the muscles contract and, when calcium falls, the muscles relax. Troponin, along with actin and tropomyosin, is the protein complex to which calcium binds to trigger the production of muscular force.
=== Peptide transport === TAP-mediated peptide transport is a multistep process. The peptide-binding pocket is formed by TAP-1 and TAP-2. Association with TAP is an ATP-independent event, 'in a fast bimolecular association step, peptide binds to TAP, followed by a slow isomerisation of the TAP complex'. It is suggested that the conformational change in structure triggers ATP hydrolysis and so initiates peptide transport. Both nucleotide-binding domains (NBDs) are required for peptide translocation, as each NBD cannot hydrolyse ATP alone. The exact mechanism of transport is not known; however, findings indicate that ATP binding to TAP-1 is the initial step in the transport process, and that ATP bound to TAP-1 induces ATP binding in TAP-2. It has also been shown that undocking of the loaded MHC class I is linked to the transport cycle of TAP caused by signals from the TAP-1 subunit.
== Structural studies == As of late 2007, 13 structures have been solved for this class of enzymes, with PDB accession codes PDB: 1AY4, PDB: 1AY5, PDB: 1AY8, PDB: 2AY1, PDB: 2AY2, PDB: 2AY3, PDB: 2AY4, PDB: 2AY5, PDB: 2AY6, PDB: 2AY7, PDB: 2AY8, PDB: 2AY9, and PDB: 3TAT.
== History == Cerebras Systems was founded in 2015 by Andrew Feldman, Gary Lauterbach, Michael James, Sean Lie, and Jean-Philippe Fricker. These five founders worked together at SeaMicro, which was started in 2007 by Feldman and Lauterbach and sold to AMD in 2012 for $334 million. The founders knew that GPUs were not the optimal semiconductors for high-level processes. However, they had to design unique cooling methods to prevent a "massive" semiconductor from burning when drawing power, unique software to route around usual microscopic manufacturing defects, and they had to invent a machine that could drill 40 screws into the wafer simultaneously without it cracking. The company had difficulty solving the problem of integrated circuit packaging: adhering the silicon to a motherboard, receiving power, and dealing with heating and cooling and the pipes to deliver and return data. It was burning through $8 million per month and spent $200 million trying to solve the problem. In July 2019, after exhaustive trial and error, the company finally produced a product that worked. In August 2019, Cerebras announced WSE-1, its first-generation Wafer-Scale Engine (WSE) semiconductors and its CS-1 supercomputing system. The CS-1 is a 19-inch rack-mounted appliance and includes a single WSE primary processor with 400,000 processing cores, 1.2 trillion transistors (twelve 100-gigabit ethernet connections), and 18 gigabytes of memory.
high-throughput Describing a method or system capable of assaying very large numbers of samples or of processing very large quantities of data extremely rapidly, generally by utilizing automation and miniaturization to greatly increase speed and efficiency. For example, high-throughput sequencing refers to modern DNA sequencing technologies that can produce sequence reads for hundreds of millions of DNA fragments simultaneously, allowing scientists to sequence entire genomes quickly and inexpensively.
Sources: en.wikipedia.org
The Maillard reaction ( MY-ar(d); French: [majaʁ]) is a chemical reaction between amino acids and reducing sugars to create melanoidins, the compounds that give browned food its distinctive flavor. Seared steaks, fried dumplings, cookies and other kinds of biscuits, breads, toasted marshmallows, falafel and many other foods undergo this reaction. It is named after French chemist Louis Camille Maillard, who first described it in 1912 while attempting to reproduce biological protein synthesis. The reaction is a form of non-enzymatic browning which typically proceeds rapidly from around 140 to 165 °C (280 to 330 °F). Many recipes call for an oven temperature high enough to ensure that a Maillard reaction occurs. At higher temperatures, caramelization (the browning of sugars, a distinct process) and subsequently pyrolysis (final breakdown leading to burning and the development of acrid flavors) become more pronounced. The reactive carbonyl group of the sugar reacts with the nucleophilic amino group of the amino acid and forms a complex mixture of poorly characterized molecules responsible for a range of aromas and flavors. This process is accelerated in an alkaline environment (e.g., lye applied to darken pretzels; see lye roll), as the amino groups (RNH+3 → RNH2) are deprotonated, and hence have an increased nucleophilicity. This reaction is the basis for many of the flavoring industry's recipes. At high temperatures, a probable carcinogen called acrylamide can form. This can be discouraged by heating at a lower temperature, adding asparaginase, or injecting carbon dioxide.
where K is an optical constant and c is the solution concentration. Using a differential refractometer (DRI) to measure the concentration of the solution, an absolute molar mass can be calculated. More accurate measurements can be made by using a low-angle static light scattering (LALS) detector, which operates at a very low angle and therefore do not require angular effects to be corrected. However, these detectors are very sensitive to particles, which leads to noisy data and are therefore rarely used. LALS detectors have largely been replaced by MALS detectors, which measures scattered light at multiple angles simultaneously and extrapolates the data to θ = 0° to obtain a weight-average molar mass. The coupling of SEC with MALS detection have become the benchmark for the determination of absolute molecular mass, particularly averages masses and distributions. Viscometry detectors, although less common, also function as detectors of absolute molar mass. Unlike light scattering photometers which do not use a calibration curve, viscometers apply a universal calibration curve where the logarithm of intrinsic viscosity multiplied by molar mass can be plotted against the retention volume from SEC. This method is effective for calculating the absolute molar mass of a wide variety of polymers, including rod-like polymers and dendrimers. Several other methods of analysis are used to determine the absolute molar mass.
Sauropsida/ Reptilia sensu lato †Araeoscelidia? †Parareptilia (polyphyletic) Diapsida/Neodiapsida †Drepanosauromorpha (placement uncertain) †Younginiformes (likely paraphyletic) †Ichthyosauromorpha (placement uncertain) †Thalattosauria (placement uncertain) †Sauropterygia (placement uncertain) †Choristodera (placement uncertain) †Kuehneosauridae (placement uncertain) Sauria/ Reptilia sensu stricto Lepidosauromorpha Lepidosauria Rhynchocephalia (tuatara) Squamata (lizards and snakes) Pantestudines (turtles and kin, placement uncertain) Archosauromorpha †Protorosauria (paraphyletic) †Rhynchosauria †Allokotosauria Archosauriformes †Phytosauria Archosauria Pseudosuchia Crocodilia (crocodilians) Avemetatarsalia/Ornithodira †Pterosauria Dinosauria †Ornithischia Saurischia (including birds (Aves))
== Clinical significance == The insulin oscillations are particularly pronounced in the portal vein delivering blood from the pancreas to the liver, which is a major insulin target. Disturbances of the insulin oscillations occur early in type 2 diabetes and may contribute to insulin resistance. Pulsatile insulin delivery to the portal vein or islet cell transplantation to the liver of diabetic patients are therefore attractive therapeutic alternatives.
Sources: en.wikipedia.org
The sequence is Thr-Lys-Pro-Arg-Pro-Gly-Pro, commonly written as TKPRPGP. It shares the first four residues with tuftsin and carries three prolines in the chain. The proline-rich tail is the main structural feature that separates it from the parent tetrapeptide.
Selank is a synthetic analogue built on the tuftsin tetrapeptide Thr-Lys-Pro-Arg. Extra proline residues were added to the C-terminus during design work. That modification is intended to make the peptide less vulnerable to rapid enzymatic degradation.
Transliteration from Russian produces variant spellings such as Selanc. Many suppliers avoid the trade-style name entirely and list the peptide sequence. Comparing sequences rather than names is the reliable way to confirm two entries describe the same molecule.
The sequence is Thr-Lys-Pro-Arg-Pro-Gly-Pro, written TKPRPGP in one-letter code. It combines the tetrapeptide tuftsin with a carboxyl-terminal Pro-Gly-Pro extension. This full sequence identifies the molecule more precisely than the research name.