The short version of tuftsin fits in a sentence. The long version — which is the one that helps — is below.
This page was last updated on 2026-08-01 and is reviewed periodically as new material appears.
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.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide | Analog of the tetrapeptide tuftsin |
| Sequence | Thr-Lys-Pro-Arg-Pro-Gly-Pro | Reported consistently across pharmacopoeial descriptions |
| Appearance | White to off-white lyophilized powder | Typical form of research-grade material |
| Solubility | Freely soluble in water | Aqueous buffers; poor in nonpolar solvents |
| Typical storage temperature | -20 degrees Celsius | Lyophilized powder; protect from moisture |
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.
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.
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.
Affecting generosity by increasing empathy during perspective taking: In a neuroeconomics experiment, intranasal oxytocin increased generosity in the Ultimatum Game by 80%, but had no effect in the Dictator Game that measures altruism. Perspective-taking is not required in the Dictator Game. However, the researchers in this experiment explicitly induced perspective-taking in the Ultimatum Game by not informing participants which role they would be placed. Serious methodological questions have arisen, however, about the role of oxytocin in trust and generosity. Empathy in healthy males is increased after intranasal oxytocin This is most likely due to the effect of oxytocin in enhancing eye gaze. There is some discussion about which aspect of empathy oxytocin might alter – for example, cognitive vs. emotional empathy. While studying wild chimpanzees, it was noted that after a chimpanzee shared food with a non-kin related chimpanzee, the subjects' levels of oxytocin increased, as measured through their urine. In comparison to other cooperative activities between chimpanzees that were monitored, including grooming, food sharing generated higher levels of oxytocin. This comparatively higher level of oxytocin after food sharing parallels the increased level of oxytocin in nursing mothers, sharing nutrients with their kin. Trust is increased by oxytocin. Study found that with the oxytocin nasal spray, people place more trust to strangers in handling their money. Disclosure of emotional events is a sign of trust in humans.
== Contraindications == Circumcision is contraindicated in certain cases. These include infants with certain genital structure abnormalities, such as a misplaced urethral opening (as in hypospadias and epispadias), curvature of the head of the penis (chordee), or ambiguous genitalia, because the foreskin may be needed for reconstructive surgery. Circumcision is contraindicated in premature infants and those who are not clinically stable and in good health. If a person is known to have or has a family history of serious bleeding disorders such as hemophilia, it is recommended that the blood be checked for normal coagulation properties before the procedure is attempted.
The alveolates are a major clade of unicellular eukaryotes of both autotrophic and heterotrophic members. Many members contain a red-algal derived plastid. One notable characteristic of this diverse group is the frequent loss of photosynthesis. However, a majority of these heterotrophs continue to process a non-photosynthetic plastid.
== Role in pathogenesis == As a pathogen, Staphylococcus aureus utilizes protein A, along with a host of other proteins and surface factors, to aid its survival and virulence. To this end, protein A plays a multifaceted role:
Several different types of fluorescent probes, like cyanine dyes, methyl violegen, or semiconductor quantum dots can be conjugated to silica nanoparticles and delivered into specific cells or injected in vivo. Carrier molecule RGD peptide has been very useful of targeted in vivo imaging. Topically applied surface-enhanced resonance Raman ratiometric spectroscopy (TAS3RS)- TAS3RS is another technique that is starting to make advancement in the medical field. It is an imaging technique that uses Folate Receptors (FR) to detect tumor lesions as small as 370 micrometers. Folate Receptors are membrane bound surface proteins that bind folates and folate conjugates with high affinity. FR is frequently overexpressed in a number of human malignancies including cancer of the ovary, lung, kidney, breast, bladder, brain, and endometrium. Raman imaging is a type of spectroscopy that is used in chemistry to provide structural fingerprint by which molecules can be identified. It relies upon inelastic scattering of photons, which result in ultra high sensitivity. There was a study that was done where two different surface enhanced resonance Raman scattering were synthesized (SERRS).
Sources: en.wikipedia.org
=== An–Av === Gloria Long Anderson (born 1938), American chemist, pioneer of nuclear magnetic resonance spectroscopy Christian B. Anfinsen (1916–1995), American chemist known for work on ribonuclease, 1972 Nobel Prize in Chemistry Andrea Angel (1877–1917), English chemist known for work on explosives Angelo Angeli (1864–1931), Italian chemist who studied nitrogen compounds such as hydrazoic acid Octavio Augusto Ceva Antunes (died 2009), Brazilian chemist, consultant for the production of anti-HIV drugs Anthony Joseph Arduengo, III (born 1952), American chemist known for chemical compounds with unusual valency Johan August Arfwedson (1792–1841), Swedish chemist who discovered lithium Anton Eduard van Arkel (1893–1976), Dutch chemist who developed a method for preparing pure titanium and other metals Svante Arrhenius (1859–1927), Swedish chemist, one of the founders of physical chemistry, he used physical chemistry to estimate the effect of atmospheric carbon dioxide the Earth's increasing surface temperature; Nobel Prize in Chemistry, 1903 Valerie Ashby (born 1965/1966), American chemist known for work on functionalized diene monomers and polymers Barbara Askins (born 1939), American chemist known for inventing a method to enhance underexposed photographic negatives Larned B.
=== Genomics and bioinformatics tools to study browning === Due to the complex nature of adipose tissue and a growing list of browning regulatory molecules, great potential exists for the use of bioinformatics tools to improve study within this field. Studies of WAT browning have greatly benefited from advances in these techniques, as beige fat is rapidly gaining popularity as a therapeutic target for the treatment of obesity and diabetes. DNA microarray is a bioinformatics tool used to quantify expression levels of various genes simultaneously, and has been used extensively in the study of adipose tissue. One such study used microarray analysis in conjunction with Ingenuity IPA software to look at changes in WAT and BAT gene expression when mice were exposed to temperatures of 28 and 6 °C. The most significantly up- and downregulated genes were then identified and used for analysis of differentially expressed pathways. It was discovered that many of the pathways upregulated in WAT after cold exposure are also highly expressed in BAT, such as oxidative phosphorylation, fatty acid metabolism, and pyruvate metabolism. This suggests that some of the adipocytes switched to a beige phenotype at 6 °C. Mössenböck et al. also used microarray analysis to demonstrate that insulin deficiency inhibits the differentiation of beige adipocytes but does not disturb their capacity for browning. These two studies demonstrate the potential for the use of microarray in the study of WAT browning.
=== Muscular disease === A meta-analysis found that creatine treatment increased muscle strength in muscular dystrophies, and potentially improved functional performance. Creatine treatment does not appear to improve muscle strength in people who have metabolic myopathies. High doses of creatine lead to increased muscle pain and an impairment in activities of daily living when taken by people who have McArdle disease.
Evidence for depression being causally associated with isotretinoin use includes 41 reports of positive challenge/dechallenge/rechallenge with isotretinoin, involving administering isotretinoin, withdrawing the drug, and then re-administering it. The majority of these cases had no psychiatric history. There is also a temporal relationship between the development of depression and initiation of isotretinoin treatment, with most cases developing after 1–2 months of treatment. Further, higher doses of isotretinoin increase the risk of developing depression, with 25% of people showing depression on a dose of 3 mg/kg/day as compared with 3–4% at normal doses. Studies have uncovered several biological processes which may credibly explain the affective changes induced by isotretinoin.
Sources: en.wikipedia.org
Selank is a synthetic seven-amino-acid peptide modeled on tuftsin, a fragment of the immunoglobulin G heavy chain. It was designed in Russia to combine anxiolytic and immunomodulatory properties in one molecule.
The first four residues of Selank reproduce the tuftsin sequence Thr-Lys-Pro-Arg. A Pro-Gly-Pro extension at the C-terminus was added to slow enzymatic breakdown and extend residence time.
It holds marketing authorization in Russia, where nasal drop formulations are sold. No equivalent approval exists in the European Union, the United States, or most other countries.
Sealed, desiccated storage at -20 °C or colder is the standard recommendation for research-grade material. Vials should reach room temperature before they are opened, which limits condensation. Repeated temperature cycling is discouraged.