Selank 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.
Updated 2025-08-28. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular class | Synthetic heptapeptide | Stabilized analog of tuftsin |
| Sequence | Thr-Lys-Pro-Arg-Pro-Gly-Pro | Single-letter form: TKPRPGP |
| Molecular formula | C33H57N11O9 | Monoisotopic mass about 751.9 Da |
| Appearance | White to off-white powder | Typically supplied as lyophilized solid |
| Solubility | Freely soluble in water | Also soluble in common polar solvents |
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.
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.
Reversed-phase high-performance liquid chromatography is the standard technique for estimating peptide purity. The result is a peak-area percentage, which describes how much of the detected material elutes as the main peak in one run. Mass spectrometry confirms the molecular mass and can reveal truncated, adducted, or otherwise modified species. Amino acid analysis or tandem mass spectrometry can address sequence fidelity when identity is in doubt. None of these measurements, taken alone, establishes that a sample is fit for any specific purpose.
Lyophilized selank is normally supplied as a dry powder and is considered stable for extended periods when kept cold and dry. Moisture uptake is the main practical threat, because absorbed water promotes both hydrolysis and aggregation in the solid state. Vials are usually warmed to room temperature before opening so that condensation does not form on the powder. Supplier documentation commonly specifies -20 °C for routine storage, with -80 °C used for material intended to be archived for years.
Once dissolved, the peptide is markedly less stable than the dry powder. Aqueous solutions are subject to backbone hydrolysis and to microbial growth when they are handled without sterile technique. Buffered solutions near neutral pH are common for short-term laboratory work, while acidic conditions are sometimes used to improve solubility. Analytical laboratories generally prepare working solutions fresh rather than storing them, and a residual water film left in a reopened vial can seed degradation even when the container appears dry.
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.
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.
Solubility behavior is a practical concern for handling. Selank dissolves readily in water and in common aqueous buffers, which simplifies preparation of working solutions. The choice of solvent, ionic strength, and pH can influence aggregation over time, particularly at higher concentrations. Aqueous solutions are typically sterile-filtered before use. Because stability depends on several variables, storage and handling notes should be treated as general guidance rather than fixed rules, and specific values are best confirmed against a certificate of analysis for each batch.
Characterization of Selank in a laboratory setting relies on standard peptide methods. Reverse-phase high-performance liquid chromatography separates the target from related impurities and provides a purity figure, commonly reported as 95 percent or higher. Mass spectrometry, typically electrospray ionization or matrix-assisted laser desorption, confirms the molecular mass and helps detect truncation or modification. Amino acid analysis can verify composition when a sequence-level check is needed. These techniques together establish identity and purity for a given lot.
Lyophilized Selank, the dry powder form, is generally stored frozen at minus 20 degrees Celsius or colder for long-term keeping. The solid is hygroscopic and should stay sealed, dry, and protected from light. Once dissolved, the peptide is less stable and is usually held refrigerated at 2 to 8 degrees Celsius for short periods. Repeated freezing and thawing is avoided because it can promote aggregation and loss of activity. Buffers and pH choice also affect how long a solution remains usable.
He claimed that on 3 August the third side began to participate in the clashes between the Georgian and South Ossetian forces, firing on both the Georgians and South Ossetians. Illarionov said that the Ossetians do not deny the Georgian reports that the Ossetians violated the ceasefire declared on 7 August by Saakashvili. According to him, by August 2008 South Ossetia had become the most militarised territory per capita in the world, surpassing even North Korea. He also said that the Georgians apparently did not have any plan to invade South Ossetia, only a plan to defend the Georgian villages in South Ossetia. In November 2008, Russian organisation Memorial said there was abundant evidence of mutual shelling before 7 August 2008. The head of Memorial, Oleg Orlov, was in South Ossetia and Georgia for two weeks. He said that firing started on August 1 along the Georgian-South Ossetian border. Orlov said that South Ossetians had attacked Georgian civilians inside South Ossetia and they had used the Tskhinvali headquarters of Russian peacekeeping force as their base. Orlov said that Russia had provoked the Georgian military operation. He added, "But Russian peacekeepers also didn't do their job properly. We know the Russian side gave arms to the Ossetians and that they used them to fire towards Georgia from Russian peacekeeping positions well before August 7." Orlov reported that Russia had begun building the road connecting Tskhinvali with Akhalgori in the spring 2008, long before the war, and it was already completely finished.
==== Ovarian function ==== In 2021, a phase I non-randomized clinical trial, the first in humans, evaluated the safety and potential benefits of injecting autologous adipose-derived stem cells (ADSCs) into the ovaries of women with premature ovarian failure (POF). Nine patients received varying doses of ADSCs (5, 10, or 15 million cells), and were followed for up to 12 months. The results showed that there were no serious side effects reported, menstruation resumed in 4 out of 9 patients, serum FSH levels decreased in 4 patients, indicating some hormonal improvement. Additionally, ovarian volume, AMH, and antral follicle count (AFC) showed variable results with no significant differences between groups. The study concluded that intra-ovarian ADSC therapy appears safe and feasible, with some signs of improved ovarian function, though results were inconsistent. Larger randomized trials are needed for confirmation.
The more serious resistance in the départements was crushed by declaring a state of siege and by the "mixed commissions". The plebiscite of 20 December ratified by a huge majority the coup d'état in favour of the prince-president, who alone reaped the benefit of the excesses of the Republicans and the reactionary passions of the monarchists.
Sources: en.wikipedia.org
In children, orthodontic treatment to expand the volume of the nasal airway, such as nonsurgical rapid palatal expansion, is common. Since the palatal suture is fused in adults, regular RPE using tooth-borne expanders cannot be performed. Mini-implant-assisted rapid palatal expansion (MARPE) has been recently developed as a non-surgical option for the transverse expansion of the maxilla in adults. This method increases the volume of the nasal cavity and nasopharynx, leading to increased airflow and reduced respiratory arousals during sleep. Changes are permanent with minimal complications.
Nevus or naevus (pl. nevi or naevi) is a nonspecific medical term for a visible, circumscribed, chronic lesion of the skin or mucosa. The term originates from naevus, which is Latin for "birthmark"; however, a nevus can be either congenital (present at birth) or acquired. Common terms (mole, birthmark, beauty mark, etc.) are used to describe nevi, but these terms do not distinguish specific types of nevi from one another.
=== Astrobiology === To understand the prospects for life to exist elsewhere in the universe, astrobiologists are interested in measuring the chemical composition of extraplanetary bodies. Because of their small size and wide-ranging functionality, microfluidic devices are suited for these remote sample analyses. From an extraterrestrial sample, the organic content can be assessed using microchip capillary electrophoresis and selective fluorescent dyes. These devices are capable of detecting amino acids, peptides, fatty acids, and simple aldehydes, ketones, and thiols. These analyses coupled together could allow detection of the key components of life, and inform the search for functioning extraterrestrial life.
== Function == Members of the ADAM family are cell surface proteins with a unique structure, possessing both potential adhesion and protease domains. Sheddase, a generic name for the ADAM metallopeptidase, functions primarily to cleave membrane proteins at the cellular surface. Once cleaved, the sheddases release soluble ectodomains with an altered location and function. Although a single sheddase may "shed" a variety of substances, multiple sheddases can cleave the same substrate resulting in different consequences. This gene encodes an ADAM family member that cleaves many proteins including TNF-alpha and E-cadherin. ADAM10 (EC#: 3.4.24.81) is a sheddase, and has a broad specificity for peptide hydrolysis reactions. ADAM10 cleaves ephrin, within the ephrin/eph complex, formed between two cell surfaces. When ephrin is freed from the opposing cell, the entire ephrin/eph complex is endocytosed. This shedding in trans had not been previously shown, but may well be involved in other shedding events. In neurons, ADAM10 is the most important enzyme, with α-secretase activity for proteolytic processing of the amyloid precursor protein. ADAM10, along with ADAM17, cleaves the ectodomain of the triggering receptor expressed on myeloid cells 2 (TREM2), to produce soluble TREM2 (sTREM2), which has been proposed as a CSF and sera biomarker of neurodegeneration. ADAM10 belongs to subfamily A, the most ancestral subfamily of ADAM proteins, which is shared by all major groups of animals, choanoflagellates, fungi, and green algae from the class Mamiellophyceae.
Sources: en.wikipedia.org
=== Analogues === 4-AcO-DMT is closely related to psilocin (4-HO-DMT) and psilocybin (4-PO-DMT). It is a lower homologue of 4-AcO-MET, 4-AcO-DET, 4-AcO-MiPT, and 4-AcO-DiPT. Other analogues of 4-AcO-DMT include 4-AcO-DPT, 4-MeO-DMT, and 4-PrO-DMT (O-propionylpsilocin). Other related prodrugs of psilocin besides 4-AcO-DMT, 4-PrO-DMT, and psilocybin include CT-4201, EB-002, RE-109 (4-GO-DMT), and MSP-1014.
Moderate alcohol consumption, one standard drink per day, by breastfeeding mothers is not known to significantly affect infants; however, the American Academy of Pediatrics strongly discourages more than two standard drinks per day. Even one or two drinks, including beer, may reduce milk intake by 20 to 23%, leading to increased agitation and poor sleep patterns. Regular heavy drinking (more than two drinks daily) can shorten breastfeeding duration and cause issues in infants, such as excessive sedation, fluid retention, and hormonal imbalances. Additionally, higher alcohol consumption may negatively impact children's academic achievement. When breastfeeding, alcohol may be consumed in moderation and does not require "Pumping-and-Dumping" (pumping and discarding breastmilk). Alcohol crosses from the blood to the breastmilk by diffusion. Thus, the concentration of alcohol in the breastmilk is approximately equal to the concentration in the maternal bloodstream at any given time. As the mother's liver processes the alcohol, more and more alcohol is pulled out of the breastmilk and back into the bloodstream. Thus, it is suggested to wait 2 hours after drinking before nursing or pumping. In the case of infrequent binge drinking, it has been shown that infants consume through breastmilk only a fraction of the alcohol their mothers have ingested. While a minute, clinically insignificant amount of alcohol may be absorbed into the infant's bloodstream, it is unlikely that this amount would cause any noticeable cognitive or neuromotor effects.
Primary processes involve initial charge separation through absorption of photons by the matrix and pooling of the energy to form matrix ion pairs. Primary ion formation occurs through absorption of a UV photon to create excited state molecules by
During his 2022 gubernatorial campaign, Moore criticized the Hogan administration for a "failure of executive leadership" on fighting climate change. He supports the renewable energy goals set by the state's Clean Energy Jobs Act of 2019, which called for a 50% reduction in greenhouse gas emissions and an electrification of the state's vehicle fleet by 2030, and has said the state should pursue "more ambitious goals" beyond carbon neutrality. He also proposed regulations to achieve 100% clean energy use by 2035 and net zero carbon emissions by 2045, electrify the state's fleet, and prioritize environmental-justice funding. Moore also said that he would establish a "cap-and-invest" program in Maryland, which would tax polluters to provide revenue for clean energy infrastructure and relief in communities of color, and promised to hire a "climate czar" in his administration, whom he appointed in November 2023. In July 2025, Moore signed an executive order ordering his administration to utilize the Maryland Department of the Environment's EnviroScreen tool, which allows users to view data on pollution burdens and health metrics by census tract, to inform their policy work and agency decisions. The order also created an interagency advisory council to develop environmental justice strategic plans in collaboration with thirteen state agencies and contained provisions calling on state agencies to accelerate their efforts in removing barriers preventing farmers from accessing land and financing.
=== Toning === Toners help balance the skin's pH and are typically used after cleansing but prior to moisturizing. They can have a number of benefits, depending on their formula and should be chosen to suit an individuals skin needs, such as reducing pores (using toners that have salicylic acid) for oily and acne skin types, brightening complexion (with toners that have vitamin C), soothing inflammation (via toners with ingredients such as aloe vera) for sensitive skin types or using toners that include retinol for aging skin, which can help to improve fine lines.
Sources: en.wikipedia.org
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.
It was developed in Russia, at the Institute of Molecular Genetics of the Russian Academy of Sciences, during the 1990s. Most published research originates from Russian institutions. Independent international replication remains limited.
Tuftsin is a natural tetrapeptide with the sequence Thr-Lys-Pro-Arg that participates in immune signaling. Selank extends that sequence with Pro-Gly-Pro at the C-terminus. The added residues are linked to greater resistance to enzymatic breakdown.
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.