This is a working overview of tuftsin, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-04-10 and is reviewed periodically as new material appears.
Most published work on selank originates from a small number of research groups in the Russian Federation. A large share of that record appears in Russian-language journals, which limits access for readers who rely on English-indexed databases. Independent replication by laboratories outside the original research network is sparse in publicly available sources. This concentration of origin and language is a frequently noted feature when the compound is summarized in broader reviews of synthetic peptides.
Reported pharmacological effects center on reduced anxiety-like behavior in animal models and on measures of memory and learning. Proposed contributing mechanisms include modulation of GABAergic signaling, shifts in monoamine turnover, and changes in the activity of enzymes that degrade neuropeptides. Effects on the expression of genes linked to neuroplasticity have also been described. No single molecular target is widely accepted, and whether the behavioral findings arise from one pathway or several remains an open question.
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro. It was designed as a stabilized analogue of tuftsin, a naturally occurring tetrapeptide fragment derived from the immunoglobulin heavy chain. The additional Pro-Gly-Pro segment at the carboxyl terminus is intended to slow enzymatic cleavage. The compound is usually described in the literature as a synthetic peptide with anxiolytic and cognitive-related activity, a label that reflects a research context rather than an approved therapeutic category.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C33H57N11O9 | Derived from the seven-residue sequence |
| Molecular weight | About 751.9 g/mol | Average mass; the monoisotopic value is slightly lower |
| Residue count | Seven amino acids | Thr-Lys-Pro-Arg-Pro-Gly-Pro |
| Parent compound | Tuftsin (Thr-Lys-Pro-Arg) | Selank extends tuftsin at the C-terminus |
| Compound class | Synthetic short peptide | Studied in a research setting; not a licensed drug in most markets |
Handling follows standard practice for research peptides. Material is weighed in a low-humidity environment because the powder absorbs atmospheric moisture. Purity is reported as the percentage area of the main peak in a chromatogram, with specifications commonly set at 95 percent or higher; values below that threshold indicate the presence of truncated or modified species. Residual trifluoroacetate from purification is often present and may affect mass balance. Certificates of analysis should state the analytical method, the column and gradient used, and the lot-specific retention time so that results can be compared across suppliers.
Identity and purity of selank are established with reversed-phase high-performance liquid chromatography coupled to mass spectrometry. The peptide elutes from C18 columns with acetonitrile gradients in water containing trifluoroacetic acid or formic acid, and detection is usually performed by ultraviolet absorbance near 214 nm. Electrospray ionization in positive mode gives a doubly protonated ion near m/z 377, consistent with a mass of about 752 Da. Amino acid analysis or tandem mass spectrometry of fragment ions confirms the sequence. Because the molecule has no aromatic residues, it lacks a usable 280 nm chromophore, so low-wavelength detection or mass spectrometry is required.
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.
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.
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.
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.
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.
Mass cytometry is a high-dimensional single-cell analysis technique that integrates flow cytometry with time of flight mass spectrometry. It is used for the determination of the properties of cells (cytometry). In this approach, antibodies are conjugated with isotopically pure elements, and these antibodies are used to label cellular proteins. Cells are nebulized and sent through an argon plasma, which ionizes the metal-conjugated antibodies. The metal signals are then analyzed by a time-of-flight mass spectrometer. The approach overcomes limitations of spectral overlap in flow cytometry by utilizing discrete isotopes as a reporter system instead of traditional fluorophores which have broad emission spectra.
Think tanks have been important allies for United States presidents since the Reagan administration, writing and suggesting policies to implement, and providing staff for the administration. For recent conservative presidents, think tanks such as The Heritage Foundation, the Hoover Institution, and the American Enterprise Institute (AEI) were closely associated with the Reagan administration. The George H. W. Bush administration worked closely with AEI, and the George W. Bush administration worked closely with AEI and the Hoover Institution. The Trump administration works closely with the Heritage Foundation. For recent liberal presidents, the Progressive Policy Institute and its parent the Democratic Leadership Council were closely associated with the Clinton administration, and the Center for American Progress was closely associated with the Obama and Biden administrations. Think tanks help shape both foreign and domestic policy. They receive funding from private donors, and members of private organizations. By 2013, the largest 21 think tanks in the US spent more than US$1 billion per year. Think tanks may feel more free to propose and debate controversial ideas than people within government. The progressive media watchdog Fairness and Accuracy in Reporting (FAIR) has identified the top 25 think tanks by media citations, noting that from 2006 to 2007 the number of citations declined 17%. The FAIR report reveals the ideological breakdown of the citations: 37% conservative, 47% centrist, and 16% liberal.
This amount increased significantly during the 1999–2003 period, when the costs generated by the reconstruction of the bridges represented $18,455.7 million. These costs are equivalent to 1.71% of the total INVÍAS budget for 2003. For 2004, costs for damage to road infrastructure dropped substantially to $680 million. The partial interruption of the roads directly affects the transport sector, food, and other private guilds, which in turn assume costs for these damages. However, generally these have not been quantified because of the difficulty they pose for being directly calculated. This presents the generalized problem of quantifying the costs associated with conflict. This is explained, in part, by the tendency in the various economic sectors not to denounce these types of actions that, in one way or another, interrupt the normal functioning of economic activities.
== Diagnostic testing == Numerous studies confirming a strong correlation between elevated Lp(a) and heart disease have led to the consensus that Lp(a) is an important independent predictor of cardiovascular disease. Animal studies have shown that Lp(a) may directly contribute to atherosclerotic damage by increasing plaque size, inflammation, instability, and smooth muscle cell growth. Genetic data also support the theory that Lp(a) causes cardiovascular disease. The European Atherosclerosis Society recommends that patients with a moderate or high risk of cardiovascular disease should have their Lp(a) levels checked. Any patient with one of the following risk factors should be screened:
== Hadamard transform time-of-flight mass spectrometry == Hadamard transform time-of flight mass spectrometry (HT-TOFMS) is a mode of mass analysis used to significantly increase the signal-to-noise ratio of a conventional TOFMS. Whereas traditional TOFMS analyzes one packet of ions at a time, waiting for the ions to reach the detector before introducing another ion packet, HT-TOFMS can simultaneously analyze several ion packets traveling in the flight tube. The ions packets are encoded by rapidly modulating the transmission of the ion beam, so that lighter (and thus faster) ions from all initially released packets of mass from a beam get ahead of heavier (and thus slower) ions. This process creates an overlap of many time-of-flight distributions convoluted in form of signals. The Hadamard transform algorithm is then used to carry out the deconvolution process which helps to produce a faster mass spectral storage rate than traditional TOFMS and other comparable mass separation instruments.
Sources: en.wikipedia.org
== Administration == Prajmaline can be administered orally, parenterally or intravenously. Three days after the last dose, a limited effect has been observed. Therefore, it has been suggested that treatment of arrhythmias with Prajmaline must be continuous to see acceptable results.
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Paper chromatography is a technique that involves placing a small dot or line of sample solution onto a strip of chromatography paper. The paper is placed in a container with a shallow layer of solvent and sealed. As the solvent rises through the paper, it meets the sample mixture, which starts to travel up the paper with the solvent. This paper is made of cellulose, a polar substance, and the compounds within the mixture travel further if they are less polar. More polar substances bond with the cellulose paper more quickly, and therefore do not travel as far.
Semmelweis, who in the 1840s formulated his rules for handwashing in the hospital, prior to the advent of germ theory, attributed disease to "decomposing animal organic matter". His ideas were rejected and his book on the topic condemned by the medical community. After Lister, however, doctors started sanitising their hands in the 1870s. Robert Koch, a pioneer in medical microbiology, worked on cholera, anthrax and tuberculosis. In his research into tuberculosis, Koch finally proved the germ theory, for which he received a Nobel Prize in 1905. In Koch's postulates, he set out criteria to test if an organism is the cause of a disease, and these postulates are still used today. Ferdinand Cohn is said to be a founder of bacteriology, studying bacteria from 1870. Cohn was the first to classify bacteria based on their morphology. Though it was known in the nineteenth century that bacteria are the cause of many diseases, no effective antibacterial treatments were available. In 1910, Paul Ehrlich developed the first antibiotic, by changing dyes that selectively stained Treponema pallidum—the spirochaete that causes syphilis—into compounds that selectively killed the pathogen. Ehrlich, who had been awarded a 1908 Nobel Prize for his work on immunology, pioneered the use of stains to detect and identify bacteria, with his work being the basis of the Gram stain and the Ziehl–Neelsen stain. A major step forward in the study of bacteria came in 1977 when Carl Woese recognised that archaea have a separate line of evolutionary descent from bacteria.
=== Gibbs–Donnan effect === In ion exchange chromatography, the Gibbs–Donnan effect is observed when the pH of the applied buffer and the ion exchanger differ, even up to one pH unit. For example, in anion-exchange columns, the ion exchangers repeal protons so the pH of the buffer near the column differs is higher than the rest of the solvent. As a result, an experimenter has to be careful that the protein(s) of interest is stable and properly charged in the "actual" pH. This effect comes as a result of two similarly charged particles, one from the resin and one from the solution, failing to distribute properly between the two sides; there is a selective uptake of one ion over another. For example, in a sulphonated polystyrene resin, a cation exchange resin, the chlorine ion of a hydrochloric acid buffer should equilibrate into the resin. However, since the concentration of the sulphonic acid in the resin is high, the hydrogen of HCl has no tendency to enter the column. This, combined with the need of electroneutrality, leads to a minimum amount of hydrogen and chlorine entering the resin.
Sources: en.wikipedia.org
== Reception and publication == Fleming's discovery was initially regarded as unimportant. Even as he showed his culture plates to his colleagues, all he received was an indifferent response. He described the discovery on 13 February 1929 before the Medical Research Club. His presentation, titled "A medium for the isolation of Pfeiffer's bacillus", did not receive any particular attention. In 1929, Fleming reported his findings to the British Journal of Experimental Pathology on 10 May 1929, and published them in the next month's issue. His article failed to attract any serious attention. Fleming himself was quite unsure of the medical application of his work and was more concerned with its application for bacterial isolation, as he concluded:
=== Genetics === PMOS has a clear genetic component and high heritability. Evidence of the genetic basis comes from family and twin studies, as well as from large genome-wide association studies. The correlation in PMOS occurrence between identical twin sisters was found to be twice as high as that between non-identical twins, suggesting a significant genetic influence. Twenty-five different genetic loci have been found to correlate with PMOS in genome-wide association studies, of which thirteen were replicated in at least one other study. Variants in genes involved in insulin signaling and androgen synthesis, including those affecting ovarian steroidogenesis, have also been associated with increased susceptibility to PMOS. Genes near some of these loci imply neuroendocrine and metabolic dysfunction, but the role of other genes is not yet clear. Men with a family history of PMOS also display some of the symptoms associated with it. For instance, brothers of women with PMOS show a higher likelihood of high AMH levels, insulin resistance, and abnormal lipid levels in the blood. Men with the genetic risk factors associated with PMOS also have higher levels of obesity, type-2 diabetes, male pattern hair loss, and cardiovascular disease. Not all similarities between family members are likely due to genetics, as PMOS and obesity in mothers can have an impact on fetal development, making it more likely for men to get metabolic disorders with age.
In 1946 and 1947, penicillin factories were established in Belarus, Ukraine, Poland, Italy and Yugoslavia with physical plant and expertise from Canada through the United Nations Relief and Rehabilitation Administration (UNRRA), of which Canadian Lester B. Pearson was the head of its supply committee. UNRRA was wound up in 1948, and its penicillin responsibilities were transferred to the World Health Organization (WHO). In Italy, Domenico Marotta negotiated with UNRRA for a penicillin plant to be built near the Sapienza University of Rome. This took longer than expected and construction did not commence until 1948. In the meantime, Chain came to the Istituto Superiore di Sanità to deliver a series of lectures on penicillin and Marotta took the opportunity to recruit him as a colleague. Chain suggested that instead of building a pilot plant, they use the UNRRA money to build an institute for research into penicillin. This became the largest of its kind in the world, with over one hundred chemists, biochemists, microbiologists and technicians, and was soon at the forefront of research into semisynthetic penicillin.
=== Ecological crisis === Yemen's political instability has been compounded and partly caused by the severe ecological crisis in the country. As of 2023, the average Yemeni has access to only 86 m3 of renewable freshwater per year for all uses, (62 gallons per day) compared to a Middle Eastern regional average of approximately 631 m3, both of which are significantly below the internationally defined threshold for water stress of 1,700 m3 per capita per year. Yemen's groundwater is the main source of water in the country but the water tables have dropped severely, leaving the country without a viable source of water. For example, in Sanaa, the water table was 30 meters below surface in the 1970s but had dropped to 1200 meters below surface by 2012. The groundwater has not been regulated by Yemen's governments. Even before the revolution, Yemen's water situation had been described as increasingly dire with some environmental analysts warning that Yemen could be among the first countries to face extreme water scarcity if current trends continue. Agriculture in Yemen takes up about 90% of water in Yemen even though it only generates 6% of GDP - however a large portion of Yemenis are dependent on small-scale subsistence agriculture. Half of agricultural water in Yemen is used to grow khat, a narcotic that most Yemenis chew. This means that in such a water-scarce country as Yemen, where half the population is food-insecure, 45% of the water withdrawn from the ever-depleting aquifers is used to grow a crop that feeds nobody.
Sources: en.wikipedia.org
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro, designed as a metabolically stabilized analogue of the endogenous tetrapeptide tuftsin. It has been studied mainly against anxiety-related and cognitive endpoints rather than as an approved medicine in most jurisdictions.
Tuftsin contains four residues, while selank carries an additional Pro-Gly-Pro segment at the carboxyl end. That extension is intended to reduce enzymatic cleavage. Comparative pharmacokinetic data in humans remain limited.
No single receptor target is widely accepted as the definitive mediator of the reported effects. Proposed contributors include GABAergic modulation, shifts in monoamine turnover, and altered neuropeptide degradation. The mechanism is treated in the literature as unresolved.
Dry powder is best kept sealed, protected from light, and held at minus 20 degrees Celsius or below. Desiccant packaging helps limit moisture uptake because the material is hygroscopic. A sealed vial should be allowed to equilibrate to room temperature before opening to reduce condensation.