tuftsin 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 2025-09-28 and is reviewed periodically as new material appears.
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.
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.
Lyophilized material is generally stable for extended periods when kept dry at or below minus twenty degrees Celsius. Working solutions are less stable, and common practice is to aliquot and freeze them so that repeated freeze-thaw cycles are avoided. Aqueous solutions are sensitive to pH extremes and to microbial growth, so short-term storage at refrigerator temperature is typical. Oxidation and hydrolysis are the principal degradation routes. Reconstitution with sterile water or a mild buffer is standard, and solutions should be protected from light.
| Property | Value | Notes |
|---|---|---|
| Molecular class | Synthetic heptapeptide | Stabilized analog of tuftsin |
| Sequence | Thr-Lys-Pro-Arg-Pro-Gly-Pro | Single-letter form: TKPRPGP |
| Molecular formula | C33H57N11O9 | Monoisotopic mass about 751.9 Da |
| Appearance | White to off-white powder | Typically supplied as lyophilized solid |
| Solubility | Freely soluble in water | Also soluble in common polar solvents |
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.
Peptide bonds are vulnerable to protease attack, and Selank is no exception. Measured half-life in serum is short, on the order of minutes in several reports, which explains why intranasal administration is the common route described in the literature. Absorption across the nasal mucosa partially bypasses first-pass hepatic metabolism. Quantitative data on human bioavailability remain limited and are difficult to compare across studies.
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.
Proposed mechanisms centre on the GABAergic system. Animal and tissue studies report changes in GABA-A receptor expression and reduced activity of GABA transaminase, the enzyme that degrades GABA. Effects on monoamine turnover, including serotonin and dopamine pathways, are also described, and a separate line of work links the peptide to increased expression of brain-derived neurotrophic factor in hippocampal tissue. Most of these findings come from rodent models and cell preparations. How the individual observations combine into a single coherent mode of action is not settled.
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.
Characterization of Selank in laboratory settings relies on standard peptide analytical techniques. Reverse-phase high-performance liquid chromatography separates the peptide from related impurities and degradation products, while mass spectrometry confirms molecular identity through accurate mass measurement. Amino acid analysis and peptide sequencing verify the primary structure when reference material is unavailable. Because Selank is a short chain, fragmentation-based analysis produces a diagnostic ion pattern that supports confident identification.
Peptide stability depends strongly on temperature, moisture, and pH. Lyophilized Selank is generally most stable when stored cold and dry, with freezer temperatures commonly used for long-term storage. In solution, the compound is susceptible to hydrolysis and to microbial growth if it is not handled aseptically. The C-terminal proline-rich extension appears to slow enzymatic cleavage relative to tuftsin, though quantitative degradation rates vary with the matrix and the conditions tested. Published stability data specific to Selank remain sparse.
=== Pharmacokinetics === Metabolism of ciprofol occurs primarily in the liver through oxidation, glucuronidation, and sulfation, resulting in the formation of the inactive metabolite M4-glucuronide, which is excreted renally. It is not necessary to adjust the dose in people with mild or moderate renal impairment, or in those with mild or moderate hepatic impairment. In elderly people, a slightly lower dose (0.3 mg/kg) appears to be similar in efficacy to the higher doses administered to younger people but is associated with fewer adverse effects. Ciprofol has a short elimination half-life, generally between 2 and 4 hours. Owing to its rapid metabolism and high clearance, the drug does not tend to accumulate in the body, even during prolonged infusions.
Olby's Australian lecture, March 2010 Salk Institute Press Release on the death of Francis Crick. The Francis Crick Papers – Profiles in Science, National Library of Medicine "Obituary: Francis Crick". The Times. London. 30 July 2004. Archived from the original on 7 November 2025. Francis Crick Obituary The Biochemist Miscellaneous
The gameplay involves capturing or defending Hybrid NPCs across four maps, incorporating mechanics inspired by Counter-Strike and Vampire Slayer. Vampire Slayer – is a teamplay mod where two sides: vampires and slayers, battle it out in a variety of atmospheric settings. Planet Half-Life called the original release "A great mod". They also reviewed Chapter IV and wrote: "The new maps fit perfectly with the atmosphere built up from the previous releases." PC Zone gave version 1.1 a rating of three out of five, Chapter III a rating of 69%, and Chapter V a rating of 91%. War in Europe – A World War II-themed mod released in 1999 that includes deathmatch, team deathmatch, and capture the flag. The player earns "promotions" by fragging, which allows purchasing of additional weapons. If the player takes a hit, they will start to bleed, which can be treated with a medkit. PC Gameplay reviewed the game in 2001 and gave a rating of six out of ten, calling it worse than Day of Defeat. Wasteland Half-Life – A post-apocalyptic-themed mod with modes for deathmatch, team deathmatch, and objective capture. PC Zone gave it a score of four out of five and said it's not as popular as it deserves to be. .NetGamer said that despite the familiar gameplay, the mod has a top-notch technical execution. They also praised the maps and the character models. Later, an updated version of the mod was released, titled The Wastes. PC Zone gave it a score 69 out of 100 and called it a worthwhile update.
== Function == Many roles for DSIP have been suggested following research carried out using peptide analogues with a greater molecular stability and through measuring DSIP-like immunological (DSIP-LI) response by injecting DSIP antiserum and antibodies.
== Production == Jalapeño pepper (a cultivar of Capsicum annuum) is one of the most typical ingredients of Mexican cuisine. This chili pepper is consumed at the rate of 7–9 kg per year, per capita. It is mostly consumed fresh but also in different forms, such as pickled, dried, and smoked. Jalapeño varieties differ in size and heat. Typically, a grower passes through a jalapeño field, picking the unripe, green jalapeños for the market. Jalapeños are green for most of the season, but in the fall, which is the end of the growing season, they naturally ripen and turn bright red. In Mexico and the United States, there is a growing market for ripe red jalapeños (the last stage of maturation). They are kept on the bush as long as possible. When they are deep red and have lost much of their moisture, they are picked to be made into chipotles. Smoking is a common technique of food preservation that provides a distinctive aroma and flavor and is traditionally carried out in a field open-oven. The smoking process can affect structural, chemical and nutritional properties of food. Furthermore, the type of wood used in the smoking process impacts the resulting smoked food. The smoking of jalapeños dates back centuries and was mainly used by the Aztecs, who are thought to have preserved the chilies by smoking them, a process they also used on meats. Chipotle production involves using firewood to dry and smoke the red jalapeño for six days in an open-smoker installation. The temperature is maintained between 65 and 75 °C, using mainly pecan wood.
Sources: en.wikipedia.org
Limbic system with smaller neurons that are more densely packed together. Given that the limbic system is the main centre of emotions and memory in the human brain, this observation may explain social impairment in ASD. Fewer and smaller Purkinje neurons in the cerebellum. New research suggest a role of the cerebellum in emotional processing and language. Increased number of astrocytes and microglia in the cerebral cortex. These cells provide metabolic and functional support to neurons and act as immune cells in the nervous system, respectively. Increased brain size in early childhood causing macrocephaly in 15–20% of ASD individuals. The brain size however normalizes by mid-childhood. This variation in brain size in not uniform in the ASD brain with some parts like the frontal and temporal lobes being larger, some like the parietal and occipital lobes being normal sized, and some like cerebellar vermis, corpus callosum, and basal ganglia being smaller than neurotypical individuals. Cell adhesion molecules that are essential to formation and maintenance of connections between neurons, neuroligins found on postsynaptic neurons that bind presynaptic cell adhesion molecules, and proteins that anchor cell adhesion molecules to neurons are all found to be mutated in ASD. Loss of function (LoF) mutations in genes relating to the function and development of the synapse. Some of those implicated include SHANK3, SCN2A, and PTEN.
== See also == Substituted cathinone 3-Chloro-N-cyclopropylcathinone (3Cl-CpC; PAL-433, RTI-6037-39) 3-Fluoromethcathinone 3-Bromomethcathinone 3-Fluoromethamphetamine 3-Methylmethcathinone 3-Chloromethamphetamine 4-Chloromethcathinone 5-Cl-bk-MPA
== M == macroevolution - macromolecular system - macromolecule - macrophage colony-stimulating factor - major histocompatibility complex - Malpighi body - Malpighi layer - marine biology - maslinic acid - mass spectrometer - maturation-promoting factor - mechanoreceptor - medicine - meiosis - melting point - membrane glycoprotein - membrane protein - membrane topology - membrane transport - memory B cell - memory T cell - Mendelian inheritance - metabolic pathway - metabolism - metabotropic glutamate receptor - metalloprotein - metaphase - metazoa - methionine - micelle - Michaelis-Menten kinetics - microbe - microbiology - microevolution - microfilament - microfilament protein - microsatellite - microscope - microtiter plate - microtubule-associated protein - mineralocorticoid receptor - minisatellite - mitochondrial membrane - mitochondrion - mitogen receptor - mitosis - mitotic spindle - mixture - modern evolutionary synthesis - molar volume - mole (unit) - molecular biology - molecular chaperone - molecular dynamics - molecular engineering - molecular evolution - molecular mechanics - molecular modelling - molecular orbital - molecular phylogeny - molecular sequence data - molecule - monoamine - monoclonal antibody - monomer - monosaccharide - monosaccharide transport protein - morphogenesis - morphogenetic field - mos gene - Mössbauer spectroscopy - MRI - MSH - mu opioid receptor - mu-chain immunoglobulin - mucin - Muller's ratchet - multiresistance - muscarinic receptor - muscle - muscle protein - mutagen - mutation - myc gene - mycology - myelin basic protein - myeloma protein - myosin
Kola nut use appears to have ancient origins. It is chewed in many West African cultures, in both private and social settings, to restore vitality and ease hunger pangs. The earliest evidence of cocoa bean use comes from residue found in an ancient Mayan pot dated to 600 BCE. Also, chocolate was consumed in a bitter and spicy drink called xocolatl, often seasoned with vanilla, chile pepper, and achiote. Xocolatl was believed to fight fatigue, a belief probably attributable to the theobromine and caffeine content. Chocolate was an important luxury good throughout pre-Columbian Mesoamerica, and cocoa beans were often used as currency. Xocolatl was introduced to Europe by the Spaniards, and became a popular beverage by 1700. The Spaniards also introduced the cacao tree into the West Indies and the Philippines. The leaves and stems of the yaupon holly (Ilex vomitoria) were used by Native Americans to brew a tea called asi or the "black drink". Archaeologists have found evidence of this use far into antiquity, possibly dating to Late Archaic times.
Sources: en.wikipedia.org
He launched tirades against international critics, particularly, United States President Barack Obama, the US government, the United Nations, and the European Union, which expressed condemnation to his unprecedented war on drugs that led to the deaths of about 3,300 people, half of which were killed by unknown assailants, and the arrest of 22,000 drug suspects and surrender of about 731,000 people.
=== Ampika's Aesthetics === Pickston is the founder and CEO of Ampika's Aesthetics, a cosmetic training business with schools in Hale, Edinburgh, Bristol, Newcastle and London's Harley Street. It was founded in 2019. The training academy offers aesthetic and cosmetic training for beginners and medical professionals to gain experience and CPD accreditation. It is regulated by OFQUAL through Qualifi.
== Characteristics == As a food ingredient, thaumatin is considered to be safe for consumption. In a chewing gum production plant, thaumatin has been identified as an allergen. Switching from using powdered thaumatin to liquid thaumatin reduced symptoms among affected workers. Additionally, eliminating contact with powdered gum arabic (a known allergen) resulted in the disappearance of symptoms in all affected workers. Thaumatin interacts with human TAS1R3 receptor to produce a sweet taste. The interacting residues are specific to old world monkeys and apes (including humans); only these animals can perceive it as sweet.
Sources: en.wikipedia.org
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.
It was developed in Russia, at the Institute of Molecular Genetics of the Russian Academy of Sciences, during the 1990s. Most published research originates from Russian institutions. Independent international replication remains limited.
Tuftsin is a natural tetrapeptide with the sequence Thr-Lys-Pro-Arg that participates in immune signaling. Selank extends that sequence with Pro-Gly-Pro at the C-terminus. The added residues are linked to greater resistance to enzymatic breakdown.
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.