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 2025-09-15 and is reviewed periodically as new material appears.
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.
Peptide bonds in selank are susceptible to hydrolysis under strongly acidic or basic conditions, and the terminal proline residues are vulnerable to exopeptidase activity in biological samples. Lyophilized powder stored dry at -20 °C typically remains stable for extended periods, whereas aqueous solutions degrade faster and may lose measurable purity within days to weeks depending on pH, temperature, and microbial load. Repeated freeze-thaw cycles promote aggregation and adsorption to container surfaces. For analytical work, solutions are usually prepared fresh, kept cold, and used within a single working day.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Identity confirmation | Reversed-phase HPLC retention time versus reference standard | Retention depends on column, gradient, and ion-pairing agent |
| Mass confirmation | Electrospray or MALDI mass spectrometry | Doubly protonated ion near m/z 377 is consistent with about 752 Da |
| Typical purity specification | 95 percent or higher by chromatographic peak area | Lower values suggest truncated or modified peptide species |
| Storage of lyophilized powder | -20 °C, desiccated, protected from light | Powder tolerates long storage better than solution |
| Storage of solution | 2-8 °C for short periods | Freeze-thaw cycling promotes aggregation and surface adsorption |
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.
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.
The compound was designed at the Institute of Molecular Genetics of the Russian Academy of Sciences during the 1980s and 1990s. The stated design goal was to retain the immunomodulatory and central nervous system activity attributed to tuftsin while improving resistance to enzymatic breakdown. Adding a proline-rich tail to the short parent peptide was a deliberate strategy, because proline residues restrict the conformations available to many peptidases. The same laboratory produced Semax, an ACTH fragment analog, and both compounds were developed in parallel as short, enzymatically stabilized peptides intended for intranasal use.
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.
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.
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.
The city currently has a large number of rail and road work sites. Although this activity has increased as a result of the 2006 Winter Olympics, parts of it had long been planned. Some of the work sites deal with general roadworks to improve traffic flow, such as underpasses and flyovers, but two projects are of major importance and will radically change the shape of the city. One is the Spina Centrale ('Central Spine') project which includes the doubling of a major railway crossing the city, the Turin-Milan railway locally known as Passante Ferroviario di Torino ('Turin Railway Bypass'). The railroad previously ran in a trench, which will now be covered by a major boulevard running from north to south of Turin, in a central position along the city. Porta Susa, on this section, will become Turin's main station to substitute the terminus of Porta Nuova with a through station. Other important stations are Stura, Rebaudengo, Lingotto and Madonna di Campagna railway stations, though not all of them belong to the layout of the Spina Centrale.
=== 13 December === Robert Magowan, a British lieutenant general and former commander of the Royal Marines, revealed that the Royal Marines were involved several times in "secret operations" in Ukraine, in "extremely sensitive context", involving "a high level of political and military risk". Denis Pushilin, Acting head of Donetsk's People of Republic claimed that half of Donetsk Oblast was under Russian control.
== Function == Histatins are antimicrobial and antifungal proteins, and have been found to play a role in wound-closure. A significant source of histatins is found in the serous fluid secreted by Ebner's glands, salivary glands at the back of the tongue, and produced by acinus cells. Here they offer some early defense against incoming microbes. The three major histatins are 1, 3, and 5, which contains 38, 32, and 24 amino acids, respectively. Histatin 2 is a degradation product of histatin 1, and all other histatins are degradation products of Histatin 3 through the process of post-translational proteolysis of the HTN3 gene product. Therefore there are only two genes, HTN1 and HTN3. The N-terminus of histatin 5 allows it to bind with metals, and this can result in the production of reactive oxygen species. Histatins disrupt the fungal plasma membrane, resulting in release of the intracellular content of the fungal cell. They also inhibit the growth of yeast, by binding to the potassium transporter and facilitating in the loss of azole-resistant species. The antifungal properties of histatins have been seen with fungi such as Candida glabrata, Candida krusei, Saccharomyces cerevisiae, and Cryptococcus neoformans. Histatins also precipitate tannins from solution, thus preventing alimentary adsorption. Histatins are a family of small, histidine-rich, cationic peptides found in human saliva. They are part of the innate immune system and play critical roles in oral health, including antifungal activity, wound healing, and cell migration.
=== Midlands Black Rhino Conservancy === The Mid West Rhinos maintain close links with the Midlands Black Rhino Conservancy. The conservancy is made up of several adjoining farms that give free rein to a number of the severely endangered Black Rhino. Each year the Mid West Rhinos stage the Midlands Black Rhino Conservancy T20 tournament. The tournament has grown from humble beginnings and now boasts participating teams from South Africa and Zambia. The proceeds from the tournament and other fundraising activities go directly to the conservancy.
Sources: en.wikipedia.org
Letsie I, who succeeded Moshoeshoe in 1870, viewed the annexation as merely a treaty of alliance and protection. Basuto chiefs therefore actively challenged the efforts of British authorities to enact major reforms without prior consultations. On 31 December 1870, Sir Henry Barkly was appointed as the new High Commissioner for Southern Africa. The British had long entertained the idea of incorporating Basutoland into the Cape Colony, and Barkly immediately pushed for annexation on the premise of the financial costs incurred by the colony's policing of Basutoland. The bill confirming the annexation was approved by the Cape Parliament on 11 August 1871.
Robertsonian translocation (ROB) A type of chromosomal translocation by which double-strand breaks at or near the centromeres of two acrocentric chromosomes cause a reciprocal exchange of segments that gives rise to one large metacentric chromosome (composed of the long arms) and one extremely small chromosome (composed of the short arms), the latter of which is often subsequently lost from the cell with little effect because it contains very few genes. The resulting karyotype shows one fewer than the expected total number of chromosomes, because two previously distinct chromosomes have essentially fused together. Carriers of Robertsonian translocations are generally not associated with any phenotypic abnormalities, but do have an increased risk of generating meiotically unbalanced gametes.
The observation of the longest carbon nanotubes grown so far, around 0.5 metre (550 mm) long, was reported in 2013. These nanotubes were grown on silicon substrates using an improved chemical vapor deposition (CVD) method and represent electrically uniform arrays of single-walled carbon nanotubes. The shortest carbon nanotube can be considered to be the organic compound cycloparaphenylene, which was synthesized in 2008 by Ramesh Jasti. Other small molecule carbon nanotubes have been synthesized since.
Sources: en.wikipedia.org
=== Stockpiling and sourcing of drugs === A 2017 study found that four U.S. states that allow capital punishment are stockpiling lethal-injection drugs that are in short supply and may be needed for life-saving medical procedures elsewhere. The federal level also involves the stockpiling of lethal-injection drugs, raising questions about their source. At least one alleged supplier, Absolute Standards, is neither registered with the FDA, nor registered as a controlled substances manufacturer with the DEA, and has seen investigations over its alleged involvement.
==== National League runs scored record (2000) ==== In a presentation of rankings of active major leaguers prior to the 2000 season, Sports Illustrated slotted Bagwell second among position players behind Ken Griffey Jr., and The Sporting News placed him sixth among all players, including pitchers. Bagwell christened the team's 2000 move to Enron Field (later renamed Minute Maid Park) with the stadium's first-ever hit and first two runs driven in, in a 6–5 exhibition victory over the New York Yankees on March 30. His two-run, ninth-inning home run against Trevor Hoffman in San Diego on June 10 won the contest for Houston, 7–6, and stopped a 10-game road losing streak. On August 14 in Philadelphia, he homered twice and tied a club record with seven RBI in a 14–7 win, shared by Rafael Ramírez and Pete Incaviglia. Five days later against Milwaukee, Bagwell again homered twice for the 299th and 300th of his career; the second home run broke an eighth-inning tie to give Houston a 10–8 win. He joined Hank Aaron, Joe DiMaggio, Frank Robinson and Ted Williams as the fifth player in major league history to record 300 home runs, 1,000 RBI and 1,000 runs scored in his first ten seasons. Bagwell finished the 2000 season with a career-high 47 home runs, .310 average, .424 OBP, .615 SLG (the second-best mark of his career) for a 152 OPS+. His 152 runs scored was the highest total in a season since Lou Gehrig in 1936, and his 295 runs scored from 1999 to 2000 set a National League two-season record.
When this was made illegal, the cathinone was modified, and the new products were sold by the Israeli company Neorganics. The products had names such as Neodoves pills, but the range was discontinued in January 2008 after the Israeli government made mephedrone illegal. The Psychonaut Research Project, an EU organisation that searches the internet for information regarding new drugs, first identified mephedrone in 2008. Their research suggested the drug first became available to purchase on the internet in 2007, made available through British contacts, contact unknown, when it was also discussed on internet forums. Mephedrone was first seized in France in May 2007, after police sent a tablet they assumed to be ecstasy to be analysed, with the discovery published in a paper titled "Is 4-methylephedrone, an "Ecstasy" of the twenty-first century?" Mephedrone was reported as having been sold as ecstasy in the Australian city of Cairns, along with ethylcathinone, in 2008. An annual survey of regular ecstasy users in Australia in 2010 found 21% of those surveyed had used mephedrone, with 17% having done so in the previous six months. The price they paid per gram varied from A$16 to $320. Europol noted they became aware of it in 2008, after it was found in Denmark, Finland and the UK. The Drug Enforcement Administration noted it was present in the United States in July 2009. By May 2010, mephedrone had been detected in all 22 EU member states that reported to Europol, as well as in Croatia and Norway.
Sources: en.wikipedia.org
Identity is confirmed by matching the retention time in reversed-phase chromatography against a reference standard and by measuring the molecular mass with mass spectrometry. Tandem mass spectrometry or amino acid analysis can verify the sequence of the seven residues. Because the peptide contains no aromatic amino acids, detection at 280 nm is not useful.
Lyophilized powder is normally stored desiccated at -20 °C, protected from light and moisture. Powder kept under these conditions is generally stable for long periods. Solutions are less stable and are usually prepared immediately before use.
A purity value from one chromatographic method does not capture every possible impurity. Related peptides with similar retention behavior, counterions, and residual solvents may not appear in the same analysis. Independent testing with an orthogonal method provides stronger assurance of identity and content.
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.