Intranasal route is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Last reviewed on 2026-05-31. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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 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.
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.
| 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 |
Clinical evidence comes mainly from small studies conducted in Russia, several of which were open-label or lacked robust blinding. Reported outcomes include lower anxiety scores, changes in attention measures, and effects on asthenic states following illness. Sample sizes are typically in the tens of participants, and independent replication outside the region is scarce. Reviews published in English generally note the limited methodological quality of the underlying trials. Whether the compound produces clinically meaningful effects under rigorous conditions remains unresolved.
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.
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.
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro, frequently abbreviated as TKPRPGP. It was designed as a structural analogue of tuftsin, a naturally occurring tetrapeptide released by enzymatic cleavage of the immunoglobulin heavy chain. The two additional proline residues at the C-terminal end extend the parent chain and change how the molecule behaves in solution. The free peptide has a calculated molecular mass of approximately 751.9 g/mol and is generally supplied as a lyophilised white to off-white powder.
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.
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.
=== Marketing controversy === In 2001, Eli Lilly's chairman, president and CEO, Sidney Taurel, told shareholders: "No medicine better symbolizes our mission than Xigris," calling it "one of our industry's genuine breakthroughs." Xigris was designed to fight sepsis, a condition that kills more than 200,000 Americans annually. It was the only approved drug for sepsis, and it costs $8,000 to treat a single patient. Lilly hoped it would be a blockbuster, with sales of at least a billion dollars a year. But, after five years on the market, sales were only $200 million. Eli Lilly used the Belsito & Company PR firm in a marketing campaign to promote Xigris. A report accused the company of initiating false reports of a shortage of the drug to boost sales. Belsito and Company spread the word that the drug was being "rationed" and physicians were being 'systematically forced' to decide who would live and who would die. As part of this effort, Lilly provided a group of physicians and bioethicists with a $1.8 million grant to form the Values, Ethics, and Rationing in Critical Care (VERICC) Task Force, purportedly to address ethical issues raised by rationing in the intensive care unit. Finally, the Surviving Sepsis Campaign was established, in theory to raise awareness of severe sepsis and generate momentum toward the development of treatment guidelines. This marketing campaign was especially troublesome because Xigris has been linked to increased risk of serious bleeding in patients who used it as well as other concerns.
=== 1950–1980: Pivot to pharmaceutical research and global expansion === Due to price declines for penicillin, Pfizer searched for new antibiotics with greater profit potential. Pfizer discovered oxytetracycline in 1950, and this changed the company from a manufacturer of fine chemicals to a research-based pharmaceutical company. Pfizer developed a drug discovery program focused on in vitro synthesis to augment its research in fermentation technology. In 1959, the company established an animal health division with a 700-acre (280 ha) farm and research facility in Terre Haute, Indiana. By the 1950s, Pfizer had established offices in Belgium, Brazil, Canada, Cuba, Mexico, Panama, Puerto Rico, and the United Kingdom. In 1960, the company moved its medical research laboratory operations out of New York City to a new facility in Groton, Connecticut. In 1980, Pfizer launched Feldene (piroxicam), a prescription anti-inflammatory medication that became Pfizer's first product to reach $1 billion in revenue. In 1965, John Powers, Jr. became chief executive officer (CEO) of the company, succeeding John McKeen. As the area surrounding its Brooklyn, NY plant fell into decline in the 1970s and 1980s, the company formed a public-private partnership with New York City that encompassed the construction of low- and middle-income housing, the refurbishment of apartment buildings for the homeless and the establishment of a charter school. In 1972, Edmund T. Pratt Jr. became CEO of the company, succeeding John Powers, Jr.
A hormone receptor is a receptor molecule that binds to a specific hormone. Hormone receptors are a wide family of proteins made up of receptors for thyroid and steroid hormones, retinoids and Vitamin D, and a variety of other receptors for various ligands, such as fatty acids and prostaglandins. Hormone receptors are of mainly two classes. Receptors for peptide hormones tend to be cell surface receptors built into the plasma membrane of cells and are thus referred to as trans membrane receptors. An example of this is Actrapid. Receptors for steroid hormones are usually found within the protoplasm and are referred to as intracellular or nuclear receptors, such as testosterone. Upon hormone binding, the receptor can initiate multiple signaling pathways, which ultimately leads to changes in the behavior of the target cells. Hormonal therapy and hormone receptors play a very large part in breast cancer treatment (therapy is not limited to only breast cancer). By influencing the hormones, the cells' growth can be changed along with its function. These hormones can cause cancer to not survive in the human body.
All work in Berlin ceased by July. Hahn and his family moved to the house of a textile manufacturer there. Life became precarious for those married to Jewish women. One was Philipp Hoernes, a chemist working for Auergesellschaft, the firm that mined the uranium ore used by the project. After the firm let him go in 1944, Hoernes faced being conscripted for forced labour. At the age of 60, it was doubtful that he would survive. Hahn and Nikolaus Riehl arranged for Hoernes to work at the KWIC, claiming that his work was essential to the uranium project and that uranium was highly toxic, making it hard to find people to work with it. Hahn was aware that uranium ore was fairly safe in the laboratory and could be mined safely using the correct equipment and procedures, but the 2,000 female slave labourers from the Sachsenhausen concentration camp who mined it in Oranienburg suffered agonising deaths because their Nazi slavedrivers wilfully neglected their safety. Another physicist with a Jewish wife was Heinrich Rausch von Traubenberg. Hahn certified that his work was important to the war effort, and that his wife Maria, who had a doctorate in physics, was required as his assistant. After he died on 19 September 1944, Maria faced being sent to a concentration camp. Hahn mounted a lobbying campaign to get her released, but to no avail, and she was sent to the Theresienstadt Ghetto in January 1945. She survived the war, and was reunited with her daughters in England.
Pitting also may be caused by a variety of systemic diseases, including reactive arthritis and other connective tissue disorders, sarcoidosis, pemphigus, alopecia areata, and incontinentia pigmenti. Because pitting is caused by defective layering of the superficial nail plate by the proximal nail matrix, any localized dermatitis (e.g., atopic dermatitis or chemical dermatitis) that disrupts orderly growth in that area also can cause pitting.
Sources: en.wikipedia.org
Ion mobility spectrometry (IMS) is a technique of ion separation in gaseous phases based on their differences in ion mobility when an electric field is applied providing spatial separation prior to MS analysis. With the introduction of DESI as an ion source for ion mobility mass spectrometry, applications for IMS have expanded from only vapor-phase samples with volatile analyses to also intact structures and aqueous samples. When coupled to a time-of-flight mass spectrometer, analysis of proteins is also possible. These techniques work in tandem to one another to investigate ion shapes and reactiveness after ionization. A key characteristic of this setup is its ability to separate the distribution of ions generated in DESI prior to mass spectrometry analysis.
The citric acid cycle is a metabolic pathway that connects carbohydrate, fat, and protein metabolism. The reactions of the cycle are carried out by eight enzymes that completely oxidize acetate (a two carbon molecule), in the form of acetyl-CoA, into two molecules each of carbon dioxide. Through catabolism of sugars, fats, and proteins, the two-carbon organic product acetyl-CoA is produced which enters the citric acid cycle. The reactions of the cycle also convert three equivalents of nicotinamide adenine dinucleotide (NAD+) into three equivalents of reduced NAD (NADH), one equivalent of flavin adenine dinucleotide (FAD) into one equivalent of FADH2, and one equivalent each of guanosine diphosphate (GDP) and inorganic phosphate (Pi) into one equivalent of guanosine triphosphate (GTP). The NADH and FADH2 generated by the citric acid cycle are, in turn, used by the oxidative phosphorylation pathway to generate energy-rich ATP. One of the primary sources of acetyl-CoA is from the breakdown of sugars by glycolysis which yield pyruvate that in turn is decarboxylated by the pyruvate dehydrogenase complex generating acetyl-CoA according to the following reaction scheme:
Analytical solution methods for non-adhesive contact problem can be classified into two types based on the geometry of the area of contact. A conforming contact is one in which the two bodies touch at multiple points before any deformation takes place (i.e., they just "fit together"). A non-conforming contact is one in which the shapes of the bodies are dissimilar enough that, under zero load, they only touch at a point (or possibly along a line). In the non-conforming case, the contact area is small compared to the sizes of the objects and the stresses are highly concentrated in this area. Such a contact is called concentrated, otherwise it is called diversified. A common approach in linear elasticity is to superpose a number of solutions each of which corresponds to a point load acting over the area of contact. For example, in the case of loading of a half-plane, the Flamant solution is often used as a starting point and then generalized to various shapes of the area of contact. The force and moment balances between the two bodies in contact act as additional constraints to the solution.
=== Actin binding === Thymosin β4 was initially perceived as a thymic hormone. However this changed when it was discovered that it forms a 1:1 complex with G (globular) actin, and is present at high concentration in a wide range of mammalian cell types. When appropriate, G-actin monomers polymerize to form F (filamentous) actin, which, together with other proteins that bind to actin, comprise cellular microfilaments. Formation by G-actin of the complex with β-thymosin (= "sequestration") opposes this. Due to its profusion in the cytosol and its ability to bind G-actin but not F-actin, thymosin β4 is regarded as the principal actin-sequestering protein in many cell types. Thymosin β4 functions like a buffer for monomeric actin as represented in the following reaction: F-actin ↔ G-actin + Thymosin β4 ↔ G-actin/Thymosin β4 Release of G-actin monomers from thymosin β4 occurs as part of the mechanism that drives actin polymerization in the normal function of the cytoskeleton in cell morphology and cell motility. The sequence LKKTET, which starts at residue 17 of the 43-aminoacid sequence of thymosin beta-4, and is strongly conserved between all β-thymosins, together with a similar sequence in WH2 domains, is frequently referred to as "the actin-binding motif" of these proteins, although modelling based on X-ray crystallography has shown that essentially the entire length of the β-thymosin sequence interacts with actin in the actin-thymosin complex.
== Further reading == Martin, Christopher S.; Chung, Tammy; Langenbucher, James W. (2017). "Part 1: Defining and Characterizing the Nature and Extent of Substance Use Disorders – Historical and Cultural Perspectives on Substance Use and Substance Use Disorders". In Sher, Kenneth J. (ed.). The Oxford Handbook of Substance Use and Substance Use Disorders: Volume 1. Oxford Library of Psychology. Oxford and New York: Oxford University Press. pp. 27–59. doi:10.1093/oxfordhb/9780199381678.013.001. ISBN 978-0-19-938167-8. LCCN 2016020729. Anthony, James; Barondess, David A.; Radovanovic, Mirjana; Lopez-Quintero, Catalina (2017). "Part 1: Psychiatric Comorbidity – Polydrug Use: Research Topics and Issues". In Sher, Kenneth J. (ed.). The Oxford Handbook of Substance Use and Substance Use Disorders: Volume 2. Oxford Library of Psychology. Oxford and New York: Oxford University Press. pp. 27–59. doi:10.1093/oxfordhb/9780199381708.013.006. ISBN 978-0-19-938170-8. LCCN 2016020729. Hernández-Serrano, Olga; Gras, Maria E.; Font-Mayolas, Sílvia; Sullman, Mark J. M. (2016). "Part VI: Dual and Polydrug Abuse – Chapter 83: Types of Polydrug Usage". In Preedy, Victor R. (ed.). Neuropathology of Drug Addictions and Substance Misuse, Volume 3: General Processes and Mechanisms, Prescription Medications, Caffeine and Areca, Polydrug Misuse, Emerging Addictions and Non-Drug Addictions. Cambridge, Massachusetts: Academic Press, imprint of Elsevier. pp. 839–849. doi:10.1016/B978-0-12-800634-4.00083-4. ISBN 978-0-12-800634-4.
Sources: en.wikipedia.org
==== United States ==== In 1987, Berkeley, California, banned CFC food containers. The following year, Suffolk County, New York, became the first U.S. jurisdiction to ban polystyrene in general. However, legal challenges by the Society of the Plastics Industry kept the ban from going into effect until at last it was delayed when the Republican and Conservative parties gained the majority of the county legislature. In the meantime, Berkeley became the first city to ban all foam food containers. As of 2006, about one hundred localities in the United States, including Portland, Oregon, and San Francisco had some sort of ban on polystyrene foam in restaurants. For instance, in 2007 Oakland, California, required restaurants to switch to disposable food containers that would biodegrade if added to food compost. In 2013, San Jose became reportedly the largest city in the country to ban polystyrene foam food containers. Some communities have implemented wide polystyrene bans, such as Freeport, Maine, which did so in 1990. In 1988, the first U.S. ban of general polystyrene foam was enacted in Berkeley, California. On 1 July 2015, New York City became the largest city in the United States to attempt to prohibit the sale, possession, and distribution of single-use polystyrene foam (the initial decision was overturned on appeal). In San Francisco, supervisors approved the toughest ban on "Styrofoam" (EPS) in the US which went into effect 1 January 2017. The city's Department of the Environment can make exceptions for certain uses like shipping medicines at prescribed temperatures.
== Diagnosis == In terms of the diagnosis of Ullrich congenital muscular dystrophy upon inspection follicular hyperkeratosis, may be a dermatological indicator, additionally also serum creatine kinase may be mildly above normal. Other exams/methods to ascertain if the individual has Ullrich congenital muscular dystrophy are:
Benzodiazepines have robust efficacy in the short-term management of generalized anxiety disorder (GAD) when standardized measures of anxiety are used as the outcome variable, but did not demonstrate a favorable dropout rate compared to placebo in one meta-analysis. A newer meta-analysis showed that benzodiazepines are significantly more effective than serotonergic agents, regardless of treatment length. More research is needed, but unfortunately, newer randomized controlled trials are scarce for the off patent benzodiazepines. According to National Institute for Health and Clinical Excellence (NICE), benzodiazepines can be used in the immediate management of GAD, if necessary. However, they should not usually be given for longer than 2–4 weeks. The only medications NICE recommends for the longer-term management of GAD are antidepressants. Likewise, the Canadian Psychiatric Association (CPA) recommends benzodiazepines alprazolam, bromazepam, lorazepam, and diazepam only as a second-line choice, if the treatment with two different antidepressants was unsuccessful. Although they are second-line agents, benzodiazepines can be used for a limited time to relieve severe anxiety and agitation. CPA guidelines state that after 4–6 weeks the effect of benzodiazepines may decrease to the level of placebo, and that benzodiazepines are less effective than antidepressants in alleviating ruminative worry, the core symptom of GAD, but that in some cases, a prolonged treatment with benzodiazepines as the add-on to an antidepressant may be justified.
== History == Pfizer brought the drug to market as Vfend. A generic version of the tablet form of voriconazole was introduced in the US in 2011 after Pfizer and Mylan settled litigation under the Hatch-Waxman Act; a generic version of the injectable form was introduced in 2012. In Europe, patent protection expired in 2011, and pediatric administrative exclusivity expired in 2016.
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.
Purity is usually reported as an HPLC area percentage, most often measured at 214 nm. Identity is confirmed separately by mass spectrometry. A certificate of analysis should state both the method and the observed value.