If you have been reading about Tuftsin and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Last reviewed on 2026-01-09. Where a claim depends on a specific study, the study is described rather than over-claimed.
Tuftsin, the parent structure, is a naturally occurring immunomodulatory tetrapeptide released from the Fc region of immunoglobulin G by spleen enzymes. Selank extends this four-residue sequence with three additional amino acids. The stated rationale is that the added tail slows enzymatic breakdown and may influence receptor interactions. How the full heptapeptide behaves at the molecular level is not firmly established, and proposed mechanisms often involve indirect modulation of neurotransmitter or immune signaling rather than a single defined target.
Selank is a synthetic heptapeptide developed in Russia. Its sequence is Thr-Lys-Pro-Arg-Pro-Gly-Pro, a seven-residue chain built around the natural tetrapeptide tuftsin. Researchers at the Institute of Molecular Genetics of the Russian Academy of Sciences first described the compound in the mid-1990s. The design combined the tuftsin core with an added Pro-Gly-Pro tail, a modification intended to extend the molecule's stability in biological fluids. Published work on the peptide has appeared mainly in Russian-language journals.
Reported activity for Selank centers on anxiolytic and nootropic effects. Russian clinical reports describe use in anxiety and in cognitive or attention-related complaints. Most of this evidence comes from studies conducted by the same research groups that developed the peptide. Independent replication in other countries remains limited, and no major Western regulatory agency has approved the compound for any indication. The gap between local reports and external verification is a recurring point in discussions of the peptide.
Solubility behavior is a practical concern for handling. Selank dissolves readily in water and in common aqueous buffers, which simplifies preparation of working solutions. The choice of solvent, ionic strength, and pH can influence aggregation over time, particularly at higher concentrations. Aqueous solutions are typically sterile-filtered before use. Because stability depends on several variables, storage and handling notes should be treated as general guidance rather than fixed rules, and specific values are best confirmed against a certificate of analysis for each batch.
Characterization of Selank in a laboratory setting relies on standard peptide methods. Reverse-phase high-performance liquid chromatography separates the target from related impurities and provides a purity figure, commonly reported as 95 percent or higher. Mass spectrometry, typically electrospray ionization or matrix-assisted laser desorption, confirms the molecular mass and helps detect truncation or modification. Amino acid analysis can verify composition when a sequence-level check is needed. These techniques together establish identity and purity for a given lot.
Lyophilized Selank, the dry powder form, is generally stored frozen at minus 20 degrees Celsius or colder for long-term keeping. The solid is hygroscopic and should stay sealed, dry, and protected from light. Once dissolved, the peptide is less stable and is usually held refrigerated at 2 to 8 degrees Celsius for short periods. Repeated freezing and thawing is avoided because it can promote aggregation and loss of activity. Buffers and pH choice also affect how long a solution remains usable.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide | Modeled on tuftsin |
| Amino acid sequence | Thr-Lys-Pro-Arg-Pro-Gly-Pro | Seven residues |
| Approximate molecular mass | Around 750 Da | Depends on counter-ion and hydration |
| Common forms | Lyophilized powder | Also described as aqueous solution |
| Primary origin of research | Russian laboratories | Mid-1990s onward |
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.
Published clinical evidence is limited. Most controlled trials were conducted in Russia, enrolled modest numbers of participants, and appeared in Russian-language journals, which restricts independent verification. Reported outcomes include lower anxiety scores, improved attention and memory measures, and changes in fatigue ratings. Reviews written in English note methodological limitations such as small samples and inconsistent endpoints. Whether the compound produces clinically meaningful benefit relative to established anxiolytics is therefore an open question rather than an established finding.
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro. It was designed at the Institute of Molecular Genetics of the Russian Academy of Sciences as a structural analogue of tuftsin, a naturally occurring tetrapeptide fragment of the immunoglobulin heavy chain. The added Pro-Gly-Pro tail was intended to slow enzymatic degradation and extend biological activity. In Russia it is registered as an anxiolytic nasal preparation, while regulators elsewhere have not approved it for clinical use.
Proposed mechanisms centre on modulation of the GABAergic system, with reports of altered expression of genes related to GABA-A receptor subunits and changed monoamine turnover. Some studies describe inhibition of enkephalinase, the enzyme that degrades endogenous enkephalins, which may prolong opioid peptide signalling. Effects on brain-derived neurotrophic factor and on cytokine expression have also been reported. These findings come largely from animal models and small human studies, and the precise primary target remains unresolved.
Dry powder is normally held at -20 degrees Celsius or lower, in a sealed container with desiccant and protection from light. Reconstituted solutions are usually kept at 2 to 8 degrees Celsius for short periods and frozen for longer ones. Proline residues at several positions are generally associated with some resistance to peptidase attack, but chemical stability still declines at neutral to alkaline pH and at elevated temperature. Exact shelf-life figures are product-specific and are not standardised across suppliers.
Identity and purity are usually assessed by reversed-phase high-performance liquid chromatography, with mass spectrometry used to confirm molecular mass and sequence information. Amino acid analysis and peptide mapping may supplement these methods. Certified reference standards are scarce, and many commercial lots are sold as research chemicals without a pharmacopoeial monograph. Regulatory treatment differs by country: Selank is a registered prescription medicine in Russia, while in the European Union and the United States it is not an approved drug and may fall under research-chemical or unapproved-product frameworks.
Selank is a hydrophilic peptide and dissolves readily in water and in aqueous buffers. The lyophilised powder is typically a white to off-white solid. Because short peptides are prone to hydrolysis and oxidation, handling benefits from limiting exposure to heat, moisture and strong light. Working solutions are commonly prepared in sterile water or saline, and repeated freeze-thaw cycles are avoided to reduce aggregation and loss of activity. These practices reflect general laboratory convention rather than published stability specifications.
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.
The two substrates of this enzyme are 3-hydroxypropionic acid and oxidised nicotinamide adenine dinucleotide (NAD+). Its products are 3-oxopropanoic acid, reduced NADH, and a proton. This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-OH group of donor with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is 3-hydroxypropanoate:NAD+ oxidoreductase. This enzyme participates in beta-alanine metabolism and propanoate metabolism.
== Cited sources == Charatan, Fred (2006). "Gulf war symptoms do not constitute a syndrome". BMJ. 333 (7569): 618. doi:10.1136/bmj.333.7569.618-b. JSTOR 40700302. PMC 1570822. PMID 16990302. Greenberg, Neil; Iversen, Amy C.; Unwin, Catherin; Hull, L.; Wessely, S. (2004). "Screening for depleted uranium in the United Kingdom armed forces: who wants it and why?". Journal of Epidemiology and Community Health. 58 (7): 558–561. doi:10.1136/jech.2003.014142. PMC 1732813. PMID 15194715. Moszynski, Peter (2003). "Royal Society warns of risks from depleted uranium". BMJ. 326 (7396): 952. doi:10.1136/bmj.326.7396.952. JSTOR 25454350. PMC 1125878. PMID 12727744. Mould, Richard F. (2001). "Radiation dose from depleted uranium can now be measured". BMJ. 322 (7290): 865–866. doi:10.1136/bmj.322.7290.865/a. JSTOR 25466697. PMC 1120031. PMID 11321019. S2CID 683662. Royal Society working group on the health hazards of depleted uranium munitions (2002). The health hazards of depleted uranium munitions: Part II (Report). London, England: The Royal Society.
==== Mechanism of action ==== The mechanism of action of biguanides is not fully understood, and many mechanisms have been proposed for metformin. Biguanides do not affect the output of insulin, unlike other hypoglycemic agents such as sulfonylureas and meglitinides. Therefore, they are effective in Type 2 diabetics; and in Type 1 diabetes when used in conjunction with insulin therapy. Mainly used in Type II diabetes, metformin is considered to increase insulin sensitivity in vivo, resulting in reduced plasma glucose concentrations, increased glucose uptake, and decreased gluconeogenesis. However, in hyperinsulinemia, biguanides can lower fasting levels of insulin in plasma. Their therapeutic uses derive from their tendency to reduce gluconeogenesis in the liver, and, as a result, reduce the level of glucose in the blood. Biguanides also tend to make the cells of the body more willing to absorb glucose already present in the bloodstream, and there again reducing the level of glucose in the plasma. Biguanides have been shown to interact with copper, specifically in mitochondria, where they interfere with cell metabolism by chelating Copper in its 2+ oxidation state (Cu(II)).
Salt (sodium chloride), dissolved in water, is used in the canning process, which helps prevent spoilage and can improve sensory characteristics. As a result, canned food can be a major source of dietary salt. Too much salt increases the risk of health problems, including high blood pressure. Therefore, health authorities have recommended limitations of dietary sodium. Many canned products are available in low-salt and no-salt alternatives. Rinsing thoroughly after opening may reduce the amount of salt in canned vegetables, since much of the salt content is thought to be in the liquid, rather than the food itself.
A mesenchymal–epithelial transition (MET) is a reversible biological process that involves the transition from motile, multipolar or spindle-shaped mesenchymal cells to planar arrays of polarized cells called epithelia. MET is the reverse process of epithelial–mesenchymal transition (EMT) and it has been shown to occur in normal development, induced pluripotent stem cell reprogramming, cancer metastasis and wound healing.
Sources: en.wikipedia.org
== Pharmacokinetics == As R7 is a slightly larger molecule than tropoflavin, 72.5 mg R7 is molecularly equivalent to 50 mg tropoflavin. Relative to a roughly molecularly equivalent dose of tropoflavin, the area-under-curve levels of R7 were found to be 7.2-fold higher upon oral administration to mice, and R7 hence has a greatly improved oral bioavailability in mice of approximately 35%. Moreover, whereas tropoflavin itself is mostly metabolized in mice within 30 minutes, tropoflavin as a metabolite was still detectable in plasma at 8 hours after administration with R7, indicating that R7 sustainably releases tropoflavin into circulation. In accordance, the terminal half-life of R7 is about 195 minutes (3.25 hours) in mice. The Tmax of R7 is about 60 minutes in mice, and its Cmax for a 78 mg/kg dose was 262 ng/mL, whereas that for a 50 mg/kg dose of tropoflavin was 70 ng/mL.
=== Venture capital === Verdine has worked in the venture capital industry as a Venture Partner with Apple Tree Partners, Third Rock Ventures, and WuXi Healthcare Ventures, and as a Special Advisor to Texas Pacific Group.
Other large parks are Parco della Pellerina, Parco Colletta, Parco Rignon, Parco Colonnetti and the University botanical gardens. Around the city are several other parks such as La Mandria Regional Park and the Parco della Palazzina di Caccia di Stupinigi, once hunting grounds of the Savoy, and those on the hills of Turin. Many parks are smaller, in the various districts: there is also a total of 240 playgrounds in these parks. In the early 1960s, mayor Amedeo Peyron had the first garden in Italy with games for children inaugurated. According to a Legambiente report from 2007, Turin is the first Italian city as far as structures and policies on childcare are concerned. One of the most famous parks featuring a children's playground is Parco della Tesoriera, which is also home to Andrea della Corte Municipal Music Library; this facility is housed in Villa Tesoriera, built in 1715 and once the Royal Treasurer's residence. The park is in the Parella suburb (Turin's West Side) and hosts many concerts in summer. Rosa Vercellana, commonly known as Rosina and, in Piedmontese as La Bela Rosin ('The Beautiful Rosin'), was the mistress and later wife of King Victor Emmanuel II. She was made Countess of Mirafiori and Fontanafredda, but never Queen of Italy. As the Savoy family refused to allow her to be buried next to her husband in the Pantheon, her children had a mausoleum built for her in a similar form and on a smaller scale in Turin, next to the road to the Castello di Mirafiori.
=== 10 January === Ukrainian steel production was reduced by about 70% in 2022 as a result of the conflict. US and Ukrainian officials stated that Russian artillery fire had declined nearly 75% in some places. The UK said most of Soledar was under Russian control, whereas Wagner claimed all.
== History == Fujirebio was founded in Tokyo, Japan in 1950 under the name Fujizoki Pharmaceutical, Co., Inc. In its early days the company developed and manufactured pharmaceutical products. The company's first IVD test was launched in 1966, a TPHA kit for syphilis testing. In 1983 the company changed name to Fujirebio Inc. Between 1998 and 2010 Fujirebio acquired several specialized IVD companies, notably Centocor Diagnostics (1998), CanAg Diagnostics (2006) and Innogenetics (2010). In 2005, Fujirebio Inc. was integrated together with the commercial laboratories SRL, Inc. ("Special Reference Laboratories", established in 1970) under the holding company Miraca Holdings Inc. (which was renamed to H.U. Group Holdings, Inc. in 2020). The current company structure, Fujirebio Holdings, Inc. was created in 2017 as a parent company of Fujirebio Inc., Fujirebio Diagnostics, Inc., Fujirebio Europe N.V. and other Fujirebio group companies. In 2022, Fujirebio acquired respectively the companies ADx NeuroSciences and Fluxus, Inc. In 2025, Fujirebio acquired Plasma Services Group, Inc.
Sources: en.wikipedia.org
== Modeling == Models have been developed to simplify conceptualization of the many processes that take place in the interaction between an organism and a chemical substance. Pharmacokinetic modelling may be performed either by noncompartmental or compartmental methods. Multi-compartment models provide the best approximations to reality; however, the complexity involved in adding parameters with that modelling approach means that monocompartmental models and above all two compartmental models are the most-frequently used. The model outputs for a drug can be used in industry (for example, in calculating bioequivalence when designing generic drugs) or in the clinical application of pharmacokinetic concepts. Clinical pharmacokinetics provides many performance guidelines for effective and efficient use of drugs for human-health professionals and in veterinary medicine. Models generally take the form of mathematical formulas that have a corresponding graphical representation. The use of these models allows an understanding of the characteristics of a molecule, as well as how a particular drug will behave given information regarding some of its basic characteristics such as its acid dissociation constant (pKa), bioavailability and solubility, absorption capacity and distribution in the organism. A variety of analysis techniques may be used to develop models, such as nonlinear regression or curve stripping.
== Litigation == In 2016, the Supreme Court imposed a fine of ₹4 crore (US$420,000) on Dharampal Satyapal Limited for breaching commitments and causing delays in resolving a 2009 tax dispute. The company contested a ₹244 crore (US$25 million) tax demand related to Central Excise Duty, briefly applied to the Settlement Commission without reaching an agreement, and later faced dismissal of its petition by the Delhi High Court. DSL subsequently sought relief from the Supreme Court in 2013, securing a stay order against the tax demand.
This led the researchers to conclude that although there was little evidence for one technique being less painful than the other at the time of application, freeze branding did produce much less inflammation in the heifers' skin one week out from their brandings. In 1998 the same researchers followed up with a similar study comparing the effectiveness of thermal imagery to behavioral cues like tail flicking and vocalizing as a proxy for pain in steers. Unsurprisingly they found that thermography was far more reliable and its results more statistically significant than human-mediated behavioral study.
A sizzler is a medley dish invented in Mumbai. It is cooked and served on a hot metal plate that is placed on a wooden holder when taken to the customer's table. The dish is inspired by the Japanese Teppanyaki, in which vegetables and meat are cooked on a very hot metal griddle, to keep the inside soft and moist, and make the outside crunchy.
diphtheriae infection (Barcoo rot, diphtheric desert sore, septic sore, Veldt sore) Cutaneous group B streptococcal infection Cutaneous Pasteurella hemolytica infection Cutaneous Streptococcus iniae infection Dermatitis gangrenosa (gangrene of the skin) Ecthyma Ecthyma gangrenosum Ehrlichiosis ewingii infection Elephantiasis nostras Endemic typhus (murine typhus) Epidemic typhus (epidemic louse-borne typhus) Erysipelas (ignis sacer, Saint Anthony's fire) Erysipeloid of Rosenbach Erythema marginatum Erythrasma External otitis (otitis externa, swimmer's ear) Felon Flea-borne spotted fever Flinders Island spotted fever Flying squirrel typhus Folliculitis Fournier gangrene (Fournier gangrene of the penis or scrotum) Furunculosis (boil) Gas gangrene (clostridial myonecrosis, myonecrosis) Glanders (equinia, farcy, malleus) Gonococcemia (arthritis–dermatosis syndrome, disseminated gonococcal infection) Gonorrhea (clap) Gram-negative folliculitis Gram-negative toe web infection Granuloma inguinale (Donovanosis, granuloma genitoinguinale, granuloma inguinale tropicum, granuloma venereum, granuloma venereum genitoinguinale, lupoid form of groin ulceration, serpiginous ulceration of the groin, ulcerating granuloma of the pudendum, ulcerating sclerosing granuloma) Green nail syndrome Group JK Corynebacterium sepsis Haemophilus influenzae cellulitis Helicobacter cellulitis Hospital furunculosis Hot tub folliculitis (Pseudomonas aeruginosa folliculitis) Human granulocytotropic anaplasmosis Human monocytotropic ehrlichiosis Impetigo contagiosa Japanese spotted fever Leptospirosis (Fort Bragg fever, pretibial fever, Weil's disease) Listeriosis Ludwig's angina Lupoid sycosis Lyme disease (Afzelius' disease, Lyme borreliosis) Lymphogranuloma venereum (climatic bubo, Durand–Nicolas–Favre disease, lymphogranuloma inguinale, poradenitis inguinale, strumous bubo) Malakoplakia (malacoplakia) Mediterranean spotted fever (Boutonneuse fever) Melioidosis (Whitmore's disease) Meningococcemia Missouri Lyme disease Mycoplasma infection Necrotizing fasciitis (flesh-eating bacteria syndrome) Neonatal toxic shock-like exanthematous disease Nocardiosis Noma neonatorum North Asian tick typhus Ophthalmia neonatorum Oroya fever (Carrion's disease) Pasteurellosis Perianal cellulitis (perineal dermatitis, streptococcal perianal disease) Periapical abscess Pinta Pitted keratolysis (keratolysis plantare sulcatum, keratoma plantare sulcatum, ringed keratolysis) Plague Primary gonococcal dermatitis Pseudomonal pyoderma Pseudomonas hot-foot syndrome Pyogenic paronychia Pyomyositis Q fever Queensland tick typhus Rat-bite fever Recurrent toxin-mediated perineal erythema Rhinoscleroma Rickettsia aeschlimannii infection Rickettsialpox Rocky Mountain spotted fever Saber shin (anterior tibial bowing) Saddle nose Salmonellosis Scarlet fever Scrub typhus (Tsutsugamushi fever) Shigellosis Staphylococcal scalded skin syndrome (pemphigus neonatorum, Ritter's disease) Streptococcal intertrigo Superficial pustular folliculitis (impetigo of Bockhart, superficial folliculitis) Sycosis vulgaris (barber's itch, sycosis barbae) Syphilid Syphilis (lues) Tick-borne lymphadenopathy Toxic shock syndrome (streptococcal toxic shock syndrome, streptococcal toxic shock-like syndrome, toxic streptococcal syndrome) Trench fever (five-day fever, quintan fever, urban trench fever) Tropical ulcer (Aden ulcer, jungle rot, Malabar ulcer, tropical phagedena) Tularemia (deer fly fever, Ohara's disease, Pahvant Valley plague, rabbit fever) Verruga peruana Vibrio vulnificus infection Yaws (bouba, frambösie, parangi, pian)
Sources: en.wikipedia.org
Selank is a synthetic peptide made of seven amino acids. It is modeled on tuftsin, a natural tetrapeptide, with an added three-residue tail. It is not a small-molecule drug.
It originates from research in Russia, associated with the Institute of Molecular Genetics of the Russian Academy of Sciences. The first descriptions date to the mid-1990s. Most published studies come from Russian laboratories.
No, Selank itself does not occur naturally. Its backbone is based on tuftsin, which is produced in the body, but the seven-residue version is a synthetic construct. It is supplied as a manufactured peptide.
Reverse-phase HPLC is the usual method and gives a percentage purity value. Mass spectrometry then confirms the molecular mass. Together they provide a basic identity and purity profile for a lot.