The short version of intranasal delivery fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-01-02. Anything still debated is marked as such rather than presented as settled.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Appearance | White to off-white powder | Lyophilised solid form |
| Solubility class | Freely soluble in water | Hydrophilic heptapeptide |
| Dry storage temperature | -20 degrees Celsius or lower | Sealed, desiccated, protected from light |
| Solution storage | 2 to 8 degrees Celsius short term | Avoid repeated freeze-thaw cycles |
| Common identification method | Reversed-phase HPLC with mass spectrometry | Confirms purity and molecular mass |
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.
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.
Proposed mechanisms center on modulation of the GABA system, but no single molecular target has been confirmed. Rodent studies report changes in GABA-A receptor expression and in the turnover of serotonin, dopamine, and norepinephrine in several brain regions. Increases in brain-derived neurotrophic factor and its receptor have also been described after repeated administration. These findings come largely from animal models, and the degree to which they describe human neurochemistry remains an open question. The mechanism is best characterized as multi-system and not fully resolved.
Pharmacokinetic data are limited. Like most short peptides, Selank is vulnerable to plasma and tissue peptidases, and its measured half-life in circulation is short, on a minutes scale. The Pro-Gly-Pro tail slows this degradation but does not eliminate it. Intranasal administration is the route described in most reports, with absorption through the nasal mucosa and a hypothesized path into the central nervous system that avoids the blood-brain barrier. Direct measurements of human brain exposure are unavailable, so distribution claims rest on inference from animal work.
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.
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.
=== Fictional characters === Link (The Legend of Zelda), in The Legend of Zelda media Link (The Matrix), in Matrix media Link, in the 1993 novel Stone Cold Link (Linkovitch Chomofsky), in the 1992 film Encino Man Link Hogthrob, in The Muppets Lancelot Link, chimpanzee, title character of Lancelot Link, Secret Chimp television series Link Larkin, in the musical Hairspray
The National Center for Complementary and Integrative Health (NCCIH) is a United States government agency which explores complementary and alternative medicine (CAM). It was created in 1991 as the Office of Alternative Medicine (OAM), and renamed the National Center for Complementary and Alternative Medicine (NCCAM) before receiving its current name in 2014. NCCIH is one of the 27 institutes and centers that make up the National Institutes of Health (NIH) within the United States Department of Health and Human Services. NCCIH has been criticized for funding and marketing pseudoscientific medicine and quackery.
It is usually well tolerated, though overdose toxicity is possible. Occasionally side effects include headache, numbness, and sleepiness. Pyridoxine overdose can cause a peripheral sensory neuropathy characterized by poor coordination, numbness, and decreased sensation to touch, temperature, and vibration. Healthy human blood levels of pyridoxine are 2.1–21.7 ng/mL. Normal doses are safe during pregnancy and breastfeeding.
=== Pharmaceuticals === Anticancer drugs that exert their pharmacological effect by interfering with menin's interactions include the approved drug revumenib and the experimental drugs bleximenib, enzomenib, icovamenib, and ziftomenib.
Sources: en.wikipedia.org
Pd complexes of RuPhos catalyze Negishi coupling of organozincs with aryl halides. This ligands tolerates hindered substrates as well as a wide range of functional groups. Its complexes also catalyze the trifluoromethylation of aryl chlorides and aminations of aryl halides.
5 July Results of the 2024 United Kingdom general election: Sir Keir Starmer becomes the prime minister of the United Kingdom, following a landslide victory for Labour in the general election. The Conservatives are reduced to just 121 seats, the lowest number of MPs in their 190-year history. Among the high-profile losses are former Prime Minister Liz Truss, former cabinet minister Sir Jacob Rees-Mogg, Commons leader Penny Mordaunt, and Defence Secretary Grant Shapps. The Liberal Democrats, led by Sir Ed Davey, achieve their best ever result with 71 seats. The Green Party achieve their best ever result, quadrupling their number of seats to four. Reform UK gain their first seats in Parliament, which includes party leader Nigel Farage taking the constituency of Clacton. The SNP suffers heavy losses, going from 48 seats to just nine. Starmer ministry: Starmer appoints his first cabinet. Angela Rayner becomes Deputy Prime Minister Rachel Reeves becomes Chancellor of the Exchequer David Lammy becomes Foreign Secretary Yvette Cooper becomes Home Secretary John Healey becomes Defence Secretary 6 July Starmer holds his first press conference as prime minister, during which he confirms that the Rwanda deportation scheme is "dead and buried". Euro 2024: After finishing 1–1 at the end of extra time, England beat Switzerland 5–3 on penalties, taking them through to the semi-finals. Andy Murray's Wimbledon career comes to an end after Emma Raducanu withdraws from the mixed doubles.
=== MtDNA of Sinhalese === Ranweera et al. (2014) found the most common mtDNA haplogroup in the Sinhalese to be, Haplogroup M and Haplogroup U (U7a), Haplogroup R (R30b) and Haplogroup G (G3a1′2). Haplogroup M represents the dispersal of modern humans around 60.000 years ago along the southern Asian coastline following a southern coastal route across Arabia and India to reach Australia short after. Haplogroup U7 is considered a West Eurasian–specific mtDNA haplogroup, believed to have originated in the Black Sea area approximately 30,000 years ago. In South Asia, U7 occurs in about 12% in Gujarat, while for the whole of India its frequency stays around 2%, and 5% in Pakistan. In the Vedda people of Sri Lanka it reaches its highest frequency of 13.33% (subclade U7a). It is speculated that large-scale immigration carried these mitochondrial haplogroups into India. Chaubey states that "considerable number of maternal lineages of Sri Lanka is shared with India, more precisely with southern part of India."
24 November – Colin Renfrew, Baron Renfrew of Kaimsthorn, 87, British archaeologist, academic and peer, member of the House of Lords (1991–2021). 1 December – Sir Richard Carew Pole, 13th Baronet, 85, British aristocrat. 2 December – Rosalie Wilkins, Baroness Wilkins, 78, British politician, member of the House of Lords (1999–2015). (death announced on this date) 8 December – Tony Lloyd, Baron Lloyd of Berwick, 95, British jurist, lord of appeal in ordinary (1993–1998), member of the House of Lords (1993–2015). 15 December – Andrew Bennett, 85, British politician, MP (1974–2005). 18 December – Patrick Conolly-Carew, 7th Baron Carew, 86, Irish equestrian and aristocrat, Member of the House of Lords as a hereditary peer (1994–1999).
== Track listing == "Strange Meridian" (Russ Gershon) – 8:28 "Premonitions" (Curtis Hasselbring) – 5:29 "The Half-Life of Desire" (Gershon) – 5:30 "He Who Hesitates" (Hasselbring) – 7:54 "Temptation" (Nacio Herb Brown, Arthur Freed) – 5:17 "Circle in the Round/I Got It Bad" (Miles Davis/Duke Ellington) – 11:18 "Red" (Robert Fripp) – 11:21
Sources: en.wikipedia.org
=== Pharmacokinetics === A single 40-mg oral dose of relugolix has been found to result in peak levels of relugolix of 29 ng/mL (47 nmol/L) after 1.5 hours. Steady-state levels are reached within 7 days with 40 mg/day relugolix administration. There is an approximate 2-fold accumulation of relugolix by 2 weeks of continuous administration. Food diminishes the oral bioavailability of relugolix by about 50%. Relugolix is a substrate for P-glycoprotein, which may have a limiting effect on its absorption and distribution. The plasma protein binding of relugolix is approximately 68 to 71% over a concentration range of 0.05 to 5 μg/mL. Relugolix is not a substrate for CYP3A4. The elimination half-life of relugolix is 36 to 65 hours across a dosage range of 20 to 180 mg/day. There is moderate to high interindividual variability in systemic exposure to relugolix. Relugolix is excreted mainly in feces (83%) and to a small degree in urine (4%). Only about 6% of a dose of relugolix is excreted unchanged.
The manner in which the company licenses its franchisees varies depending on the region, with some regional franchises, known as master franchises, responsible for selling franchise sub-licenses on the company's behalf. Burger King's relationship with its franchises has not always been harmonious. Occasional spats between the two have caused numerous issues; in several instances, the relations between the company and its licensees have degenerated into precedent-setting court cases. Burger King's Australian franchise Hungry Jack's is the only franchise to operate under a different name due to a trademark dispute with a similarly named restaurant in Adelaide, South Australia, and a series of legal cases between the two.
A 2021 case report documented a 72‑year‑old woman with Lewy body dementia who developed fatal neuroleptic malignant syndrome (NMS) after receiving a single 156 mg intramuscular injection of paliperidone palmitate; she remained comatose and died following a prolonged hospital course after palliative care measures were initiated. The use of high‑dose, high‑potency, or long‑acting injectable formulations of antipsychotics increases the risk of developing NMS. Multiple additional case reports of NMS linked to paliperidone palmitate have been published, including a 63-year-old man (2025) who survived after treatment, and cases in a 29-year-old woman who developed severe, treatment‑refractory NMS after two doses of paliperidone palmitate (2025) and a 24-year-old man (2025).
William Osler Health System, Ronald McDonald House Charities, AdvaMed, Arthritis Australia, Drugs for Neglected Diseases Initiative, GISAID, Heart and Stroke Foundation of Canada, Mount Sinai Hospital (Toronto), and Truth Initiative.
Sources: en.wikipedia.org
Dry powder is normally held at -20 degrees Celsius or below in a sealed, light-protected container with desiccant. Brief room-temperature handling during weighing is generally tolerated. Storage instructions vary between suppliers, so the accompanying certificate of analysis should be followed.
Reversed-phase HPLC establishes purity, while mass spectrometry confirms the expected molecular mass. Sequence confirmation may use tandem mass spectrometry or peptide mapping. A certificate of analysis typically reports these results alongside the analytical method applied.
In Russia it is a registered medicine available by prescription. In many other countries it is not approved for human use and is supplied only as a research chemical. Import and possession rules differ by jurisdiction, and buyers are responsible for checking local requirements.
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.