Everything below concerns reverse-phase HPLC. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2026-01-26. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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.
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 |
|---|---|---|
| Route studied | Intranasal | Predominant route in published reports |
| Circulation stability | Short, minutes scale | Peptidases cleave it; the tail slows the process |
| Analytical method | RP-HPLC with mass spectrometry | Used for identity and purity assessment |
| Reported outcome domains | Anxiety and cognitive measures | Derived from small, mostly regional trials |
| Regulatory status | Marketed in Russia | Availability outside that market is limited |
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 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.
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.
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.
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.
Russia claimed to have taken the village of Klishchiivka in Donetsk Oblast for the second time since the start of the invasion in 2022. Russian drone strikes on power facilities in Sumy cut power to over half a million consumers in Sumy, Chernihiv, and Kharkiv Oblasts. Ukraine claimed to have shot down a Russian Su-25 jet near Pokrovsk. A police officer was killed in a Russian drone strike near Vovchansk. A Russian court sentenced a resident of Chita to 12 years' imprisonment for spying for Ukraine. The United Kingdom accused China of supplying lethal aid to Russia. The SBU announced it had upgraded its Sea Baby USV to launch Grad rockets.
== Centers and Institutes for Advanced Research & Education == Center for Advanced Photonics Research Center for Biophysics and Computational Biology Center for Computational Genetics and Genomics Center for Data Analytics and Biomedical Informatics Center for Materials Theory Institute for Computational Molecular Science Sbarro Health Research Organization
Symptoms of overdose include respiratory depression, drowsiness leading to coma and sometimes to death, drooping of skeletal muscles, low heart rate, and decreasing blood pressure. At the hospital, individuals with hydromorphone overdose are provided supportive care, such as assisted ventilation to provide oxygen and gut decontamination using activated charcoal through a nasogastric tube. Opioid antagonists, such as naloxone, also may be administered concurrently with oxygen supplementation. Naloxone works by reversing the effects of hydromorphone, and is administered only in the presence of significant respiratory depression and circulatory depression. Sugar cravings associated with hydromorphone use are the result of a glucose crash after transient hyperglycemia following injection, or a less profound lowering of blood sugar over a period of hours, in common with morphine, heroin, codeine, and other opioids.
== Research == (2R,6R)-HNK is under development by the National Institute of Mental Health (NIMH) in the United States for the treatment of depression. As of late 2019, it is in phase I clinical trials for this indication. It is also under development under the developmental code name SPL-801-B by Cybin for depressive disorders.
=== COVID 19 === The COVID 19 pandemic marked a new chapter in Hetero’s public health contributions. In March 2020, as the pandemic took hold, Hetero donated INR 10 crore to the Telangana government’s COVID relief fund, composed of 5 crores in direct funding and 5 crores in essential medicines including Hydroxychloroquine Sulphate, Lopinavir/Ritonavir and Oseltamivir. During this period, Hetero also began supplying medicines to countries such as the United States, Italy, Spain, Israel, and Algeria. In May 2020, Hetero entered a licensing agreement with Gilead Sciences to manufacture and distribute a generic version of Remdesivir in 127 countries. The Drug Controller General of India granted manufacturing and marketing approval on 21 June 2020, making Covifor the first generic Remdesivir approved in India. An initial consignment of 20000 Vials was distributed within India across major cities including Hyderabad, Delhi, Mumbai, Kolkata and Chennai, priced at ₹5400 per vial. By August 2020, Hetero had supplied approximately 800000 doses of Remdesivir in India alone, treating more than 100000 patients. In the same month, Hetero received authorization from the South African Health Products Regulatory Authority (SAHPRA) to import 'Remdesivir' in South Africa for the treatment for Covid-19, and committed to supplying 60000 vials a month. In July 2020, Hetero received approval from the DCGI to manufacture and market a generic version of Favipiravir tablets under the name Favivir, which is used to treat patients with mild to moderate COVID-19 symptoms.
Sources: en.wikipedia.org
==== Distribution ==== Trazodone is not sequestered into any tissue. The medication is 89 to 95% protein-bound. The volume of distribution of trazodone is 0.8 to 1.5 L/kg. Trazodone is highly lipophilic.
=== Venezuela === On 18 August 2025, Maduro said the US "has gone mad and has renewed its threats to Venezuela's peace and tranquility" and "announced the planned deployment of more than 4.5 million militia members" around Venezuela. The Economist was skeptical of the announcement, stating, "Election receipts show he received fewer than 3.8m votes last year; it is improbable that more people would fight to defend him than would vote for him." The International Institute for Strategic Studies estimated the militia had 343,000 members as of 2020. The BBC reported that many of the recently mobilized militia are "mostly made up of volunteers from poor communities, although public sector workers have reported being pressured into joining them as well." On 25 August, Maduro "said 15,000 'well armed and trained' men had been deployed to states near the Colombian border," per The Economist.
== Alternatives == Other algorithms and software for searching in structure databases are CFM-ID, ICEBERG, MetFrag, MS-FINDER, MetaboScape® (Bruker), MassHunter (Agilent) or Compound Discoverer™ (Thermo Fisher Scientific).
== Medical uses == Pegcetacoplan is indicated (approved by FDA and EMA) to treat adults with paroxysmal nocturnal hemoglobinuria. In February 2023, the US FDA indication was updated to include the treatment of people with geographic atrophy secondary to age-related macular degeneration. The medication is given through a subcutaneous infusion for paroxysmal nocturnal hemoglobinuria and through intravitreal injection for age-related macular degeneration.
Sources: en.wikipedia.org
This micelle controlled technique provides for unique opportunities for solving complicated separation problems. Despite the poor efficiency of MLC, it has been successfully used in many applications. The use of MLC in the future appears to be extremely advantages in the areas of physiological fluids, pharmaceuticals, and even inorganic ions. The technique has proven to be superior over ion-pairing and ion-exchange for many applications. As new approaches are developed to combat the poor efficiency of MLC, its application is sure to spread and gain more acceptance.
=== Notable cases === In 1987, fifteen-year-old Mickey Hays, who had progeria, appeared along with Jack Elam in the documentary I Am Not a Freak. Elam and Hays first met during the filming of the 1986 film The Aurora Encounter, in which Hays was cast as an alien. The friendship that developed lasted until Hays died in 1992, on his 20th birthday. Elam said, "You know I've met a lot of people, but I've never met anybody that got next to me like Mickey." Harold Kushner, who among other things wrote the book When Bad Things Happen to Good People, had a son, Aaron, who died at the age of 14 in 1977 of progeria. Margaret Casey, a 29-year-old woman with progeria who was then believed to be the oldest survivor of the premature aging disease, died on Sunday, May 26, 1985. Casey, a freelance artist, was admitted to Yale New Haven Hospital on the night of May 25 with respiratory problems, which caused her death. Sam Berns was an American activist with the disease. He was the subject of the HBO documentary Life According to Sam. Berns also gave a TEDx talk titled "My Philosophy for a Happy Life" on December 13, 2013. Hayley Okines was an English progeria patient who spread awareness of the condition. Leon Botha, the South African painter and DJ who was known, among other things, for his work with the hip-hop duo Die Antwoord, lived with progeria. He died in 2011, aged 26. Alexandra Peraut is a Catalan girl with progeria; she has inspired the book Una nena entre vint milions ('A girl in 20 million'), a children's book to explain progeria to youngsters.
The effects of drugs displacing each other and changing the clinical effect (though important in some examples) is vastly overestimated usually and a common example incorrectly used to display the importance of this effect is the anticoagulant warfarin. Warfarin is highly protein-bound (>95%) and has a low therapeutic index. Since a low therapeutic index indicates that there is a high risk of toxicity when using the drug, any potential increases in warfarin concentration could be very dangerous and lead to hemorrhage. In horses, it is very true that if warfarin and phenylbutazone are administered concurrently, the horse can develop bleeding issues which can be fatal. This is often explained as being due to the effect of phenylbutazone ejecting warfarin from its plasma protein, thus increasing the concentration of free warfarin and increasing its anticoagulant effect. However, the real problem is that phenylbutazone interferes with the liver's ability to metabolize warfarin so free warfarin cannot be metabolized properly or excreted. This leads to an increase in free warfarin and the resulting bleeding problems.
Sources: en.wikipedia.org
Reports describe effects on GABA-A receptor expression, monoamine turnover, and neurotrophic factor levels. These are proposed mechanisms drawn mainly from animal models. No single molecular target has been established.
Intranasal delivery is the route described in most published work. It is used because the peptide is degraded quickly once it reaches circulation. Direct evidence of brain penetration in humans is lacking.
Most trials are small, regionally concentrated, and often lack rigorous blinding or placebo control. Independent replication is limited. Reviews in English generally rate the evidence as preliminary.
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.