The short version of Intranasal delivery fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-01-18. Anything still debated is marked as such rather than presented as 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.
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.
Animal studies have examined behaviour in tests of anxiety, memory retention and stress response, and several report changes in neurotrophic or neurotransmitter-related markers. The human evidence base is much smaller, consisting mainly of short trials conducted in Russia with limited reporting in English-language journals. Sample sizes are modest and outcome measures vary between studies, so the findings are best described as preliminary. Independent replication under modern trial standards has not been widely reported.
Outside its country of origin the compound is generally handled as a research chemical rather than an approved medicine. No regulatory approval from the United States Food and Drug Administration or the European Medicines Agency has been granted for human use. Identity and purity are normally checked by reverse-phase high-performance liquid chromatography, with mass spectrometry used to confirm the molecular mass. Lyophilised material is stored cold and desiccated, and repeated freeze-thaw cycles are avoided.
| 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 |
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.
Published clinical work is concentrated in Russian-language journals and generally involves small samples without independent replication. Systematic reviews in English note the shortage of randomised, placebo-controlled trials and the difficulty of verifying methods from translated reports. Outcome measures vary between studies, which complicates pooling of results. Interest in the compound as a cognitive or anxiolytic agent therefore rests on a thinner evidence base than the volume of citations suggests. Replication in well-powered trials with preregistered endpoints would be needed before firm conclusions about efficacy can be drawn.
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.
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.
=== Immunotoxicity === Patulin was found to be immunotoxic in a number of animal and even human studies. Reduced cytokine secretion, oxidative burst in macrophages, increased splenic T lymphocytes, and increased neutrophil numbers are a few endpoints noticed. However, dietary relevant exposure would not be likely to alter immune response.
Banana Skids Climpies Double Lollies Fruity Pops Fun Gums Snap & Crackle Mr Chews Rainbow Dust Rainbow Drops Love Hearts Double Dip Tango Orange Flavour Chew Bar Stinger Tutti-Fruiti Flavour Chew Bar Crystal Fruits
==== Role in atmospheric chemistry ==== As a short-lived but very reactive carbonyl compound, HCHO is important in the oxidation chemistry of the troposphere. It is a key source of odd-hydrogen radicals (HOx = OH + HO2) that help to sustain the atmosphere's oxidative capacity. It is also an important ozone precursor. HCHO removal in the troposphere occurs primarily via photodissociation, through two main pathways: molecular and radical-forming channels, the threshold wavelengths for which are given in parentheses:
Defatted soy flour is obtained from solvent extracted flakes and contains less than 1% oil. "Natural or full-fat soy flour is made from unextracted, dehulled beans and contains about 18% to 20% oil." Its high oil content requires the use of a specialized Alpine Fine Impact Mill to grind rather than the usual hammer mill. Full-fat soy flour has a lower protein concentration than defatted flour. Extruded full-fat soy flour, ground in an Alpine mill, can replace/extend eggs in baking and cooking. Full-fat soy flour is a component of Cornell bread. Low-fat soy flour is made by adding some oil back into defatted soy flour. Fat levels range from 4.5% to 9%. High-fat soy flour can also be produced by adding back soybean oil to defatted flour, usually at 15%. Soy lecithin can be added (up to 15%) to soy flour to make lecithinated soy flour. It increases dispersibility and gives it emulsifying properties. Soy flour has 50% protein and 5% fiber. It has higher levels of protein, thiamine, riboflavin, phosphorus, calcium, and iron than wheat flour. It does not contain gluten. As a result, yeast-raised breads made with soy flour are dense in texture. Among many uses, soy flour thickens sauces, prevents staling in baked food, and reduces oil absorption during frying. Baking food with soy flour gives it tenderness, moistness, a rich color, and a fine texture. Soy grits are similar to soy flour, except the soybeans have been toasted and cracked into coarse pieces. Kinako is a soy flour used in Japanese cuisine. Section reference: Circle & Smith (1972, p. 442)
Sources: en.wikipedia.org
==== Medallists ==== The Reverend Canon William Matthew Adair. Rector, St Columba's Parish, Portadown. For services to the Church of Ireland and to the community in Portadown, County Armagh. Sean Adcock. Master Craftsman. For services to Dry Stone Walling. Rasheed Alawiye. Detective Inspector, Metropolitan Police Service. For services to Policing, and to Diversity and Inclusion. Christopher Allen. For services to the community in Chesterfield, Derbyshire. Dr. Jahangir Alom. Doctor and Campaigner, NHS. For services to Tackling Health Inequalities, particularly during Covid-19. Carl Peter Anglim. Lately Chair, Oxfordshire Youth. For services to Young People. Margaret Helen Archibald. Founder, Everyone Matters. For services to Music. Reverend Margaretha Catharina Maria Armitstead. For services to the community in Littlemore, Oxfordshire. Keith Morton Armour. Fundraiser, Children's Hospices Across Scotland. For Charitable Services. Olive Arnold. For services to the community in Bronington, Shropshire. Robert Arnott. For services to the community in Coventry. Waqas Arshad. Chair, Bradley Big Local. For services to Families with Mental Health Issues in Lancashire. Saeqa Ashraf. For services to Law Enforcement. Reverend Christine Joyce Aspinall. For services to the community in Old Trafford, Greater Manchester. Moses Olawole Ayoola. Director, Estates and Facilities, Lewisham and Greenwich NHS Trust and Guy's and St Thomas' NHS Foundation Trust. For services to Leadership in the NHS. Enid Bacon. Founder, Beck Row Preschool, Bury St Edmunds. For services to Early Education.
== Method == Electron probe microanalysis (EMPA), Synchrotron micro-XRF (SR-M-XRF), Time-of-flight secondary ion mass spectrometry (TOF-SIMS), Laser induced breakdown spectroscopy (LIBS), Atomic emission spectrometry, x-ray fluorescence spectrometry with higher energy synchrotron radiation (SR-XFS) and Laser ablation-Inductively coupled plasma mass spectrometry (LA-ICP-MS) are all methods of gold fingerprinting. The most common method is LA-ICP-MS primarily because it is quasi-nondestructive, allowing for the preservation of the samples and convenient as samples require little to no preparation. Laser ablation allows for high spatial resolution sampling while the inductively coupled plasma mass spectrometry provides high sensitivity to identify extremely small amounts of trace elements within the gold. This method can also be conducted outside of a lab with the assistance of a portable device that uses a diode pumped solid state laser and fiber-optics, making fingerprinting more convenient as it eliminates the need for transfer of gold to a specific lab. Advantages of LA-ICP-MS include reduced sample preparation, no sample size requirements, reduced spectral interference and increased sample throughput. Over the past 32 years, LA-ICP-MS has been used for archaeological, biological and forensic purposes. For example a group of gold foil fragments dating back to the 5th Century B.C.E. were analysized by LA-ICP-MS uncovering information on their manufacturing process, function and relationship to one another.
This was also the belief of geologist Palmer, who convinced Steven Jones that the helium-3 occurring naturally in Earth perhaps came from fusion involving hydrogen isotopes inside catalysts like nickel and palladium. This led their team in 1986 to independently make the same experimental setup as Fleischmann and Pons (a palladium cathode submerged in heavy water, absorbing deuterium via electrolysis). Fleischmann and Pons had much the same belief, but they calculated the pressure to be of 1027 atmospheres, when cold fusion experiments achieve a loading ratio of only one to one, which has only between 10,000 and 20,000 atmospheres. John R. Huizenga says they had misinterpreted the Nernst equation, leading them to believe that there was enough pressure to bring deuterons so close to each other that there would be spontaneous fusions.
Sources: en.wikipedia.org
=== By other animals === Humans are not always the only species to bury their dead. Chimpanzees and elephants are known to throw leaves and branches over fallen members of their family groups. In one instance, an elephant which trampled a human mother and child buried its victims under a pile of leaves before disappearing into the bushes. In 2013, a viral video caught a dog burying a dead puppy by pushing sand with its own nose. It is presumed, however, that since dogs retain the instinct to bury food, this is what is being depicted in the video. In social insects, ants and termites also bury their dead nestmates depending on the properties of the corpse and the social context. Laboratory rats had been observed using bedding material to bury dead conspecifics placed in their test chamber.
=== High school, early criminal activity, military service === Marrow moved to the Crenshaw District of Los Angeles when he was in the eighth grade. He attended Palms Junior High, which was predominantly made up of white students, and included black students who traveled by bus from South Central to attend. He then attended Crenshaw High School, which was almost entirely made up of black students. Marrow stood out from most of his friends because he did not drink alcohol, smoke tobacco, or use drugs. During Marrow's time in high school, gangs became more prevalent in the Los Angeles school system. Students who belonged to the Crips and Bloods gangs attended Crenshaw, and fought in the school's hallways. Marrow, while never an actual gang member, was affiliated with the former. Marrow began reading the novels of Iceberg Slim, which he memorized and recited to his friends, who enjoyed hearing the excerpts and told him, "Yo, kick some more of that by Ice, T", giving Marrow his nickname. Marrow and other Crips wrote and performed "Crip Rhymes". His music career started with the band of the singing group The Precious Few of Crenshaw High School. Marrow and his group opened the show, dancing to a live band. The singers were Thomas Barnes, Ronald Robinson and Lapekas Mayfield. In 1975, at the age of seventeen, Marrow began receiving Social Security benefits resulting from the death of his father and used the money to rent an apartment for $90 a month. He sold cannabis and stole car stereos to earn extra cash, but he was not making enough to support his pregnant girlfriend.
The Horizontal Working Party on Drugs (better known as Horizontal Drug Group or HDG) is a Council Working Party, a preparatory body of the Council of the European Union established in 1997, responsible for the lead and management of the work of the council and of the European Union (EU) on drug policy. The HDG meets monthly in Brussels's Europa building or in the Justus Lipsius building, and prepares all relevant legislation and political documents to be adopted by EU's Committee of Permanent Representatives (COREPER II) and subsequently by the Council, such as EU drugs strategies, action plans on drugs, and statements on drug-related aspects to be presented at international fora like the United Nations Commission on Narcotic Drugs. Since 2018, the HDG is also responsible to establish the imperative mandate for the vote on international scheduling by member state of the EU at the Commission on Narcotic Drugs. The HDG engages and closely collaborates with other EU institutions like the European Monitoring Centre for Drugs and Drug Addiction and Europol. There are frequent meetings of EU countries' national drugs coordinators held as part of HDG meetings. In addition, the HDG regularly meets with delegates from other regions and third countries within the EU's area of interest (Russia, Turkey, the Western Balkans, the United States within a so-called "Transatlantic Dialogue", Western Africa, Andes Community, and with countries from Latin America and the Caribbean within the "Technical Committee EU/LAC").
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.
Most published work uses intranasal application, either as drops or as a nasal spray. Injection routes appear in a smaller set of animal experiments. Oral use is uncommon in the literature because peptide breakdown and poor absorption limit this route.