This is a working overview of TP-7, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-07-07 and is reviewed periodically as new material appears.
Handling follows standard practice for research peptides. Material is weighed in a low-humidity environment because the powder absorbs atmospheric moisture. Purity is reported as the percentage area of the main peak in a chromatogram, with specifications commonly set at 95 percent or higher; values below that threshold indicate the presence of truncated or modified species. Residual trifluoroacetate from purification is often present and may affect mass balance. Certificates of analysis should state the analytical method, the column and gradient used, and the lot-specific retention time so that results can be compared across suppliers.
Identity and purity of selank are established with reversed-phase high-performance liquid chromatography coupled to mass spectrometry. The peptide elutes from C18 columns with acetonitrile gradients in water containing trifluoroacetic acid or formic acid, and detection is usually performed by ultraviolet absorbance near 214 nm. Electrospray ionization in positive mode gives a doubly protonated ion near m/z 377, consistent with a mass of about 752 Da. Amino acid analysis or tandem mass spectrometry of fragment ions confirms the sequence. Because the molecule has no aromatic residues, it lacks a usable 280 nm chromophore, so low-wavelength detection or mass spectrometry is required.
Peptide bonds in selank are susceptible to hydrolysis under strongly acidic or basic conditions, and the terminal proline residues are vulnerable to exopeptidase activity in biological samples. Lyophilized powder stored dry at -20 °C typically remains stable for extended periods, whereas aqueous solutions degrade faster and may lose measurable purity within days to weeks depending on pH, temperature, and microbial load. Repeated freeze-thaw cycles promote aggregation and adsorption to container surfaces. For analytical work, solutions are usually prepared fresh, kept cold, and used within a single working day.
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.
| Property | Value | Notes |
|---|---|---|
| Identity confirmation | Reversed-phase HPLC retention time versus reference standard | Retention depends on column, gradient, and ion-pairing agent |
| Mass confirmation | Electrospray or MALDI mass spectrometry | Doubly protonated ion near m/z 377 is consistent with about 752 Da |
| Typical purity specification | 95 percent or higher by chromatographic peak area | Lower values suggest truncated or modified peptide species |
| Storage of lyophilized powder | -20 °C, desiccated, protected from light | Powder tolerates long storage better than solution |
| Storage of solution | 2-8 °C for short periods | Freeze-thaw cycling promotes aggregation and surface adsorption |
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.
Reported activity for Selank centers on anxiolytic and nootropic effects. Russian clinical reports describe use in anxiety and in cognitive or attention-related complaints. Most of this evidence comes from studies conducted by the same research groups that developed the peptide. Independent replication in other countries remains limited, and no major Western regulatory agency has approved the compound for any indication. The gap between local reports and external verification is a recurring point in discussions of the peptide.
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 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.
== Reception == In 2015, Entertainment Weekly highlighted the scene where Kirk reads the United States Constitution, as one of the most important moments in that character's life. WhatCulture ranked this episode the 15th worst episode of the Star Trek franchise. In 2016, SyFy included this episode in a group of Star Trek franchise episodes they felt were commonly disliked but "deserved a second chance". In 2017, this episode was rated the 8th worst episode of the Star Trek franchise up to that time, by ScreenRant. In 2018, CBR included this episode on a ranking of episodes they stated were "So Bad They Must Be Seen". CBS News listed "The Omega Glory" as one of the worst episodes of the original series. In 2017, Den of Geek ranked this episode as the 5th worst Star Trek episode of the original series.
Alfred Russel Wallace's 1879 book Australasia, Ian Todd's 1974 book Island Realm: A Pacific Panorama and Dean Kohlhoff's 2002 book Amchitka and the Bomb: Nuclear Testing in Alaska all associate the Aleutian Islands with the Oceania region due to their status as remote islands in the Pacific. The islands, having biogeographical and ethnocultural affinities to North America, are not ordinarily considered a part of the region.
== Higher order multifunctionality == In the case of the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH), in addition to the large number of alternate functions it has also been observed that it can be involved in the same function by multiple means (multifunctionality within multifunctionality). For example, in its role in maintenance of cellular iron homeostasis GAPDH can function to import or extrude iron from cells. Moreover, in case of its iron import activities it can traffic into cells holo-transferrin as well as the related molecule lactoferrin by multiple pathways.
== Portraits == The National Portrait Gallery, London lists 17 portraits of Dorothy Hodgkin including an oil painting of her at her desk by Maggi Hambling and a photograph portrait by David Montgomery. Graham Sutherland made preliminary sketches for a portrait of Dorothy Crowfoot Hodgkin in 1978. One sketch is in the collection of the Science History Institute and another at the Royal Society in London. The portrait was never finished. A portrait of Dorothy Hodgkin by Bryan Organ was commissioned by private subscription to become part of the collection of the Royal Society. Accepted by the president of the society on 25 March 1982, it was the first portrait of a woman Fellow to be included in the Society's collection.
=== Pentomic organization === In 1957, the division implemented the pentomic organization, officially Reorganization of the Airborne Division (ROTAD), to better prepare for tactical nuclear war in Europe. Five battle groups, each with a headquarters and service company, five rifle companies and a mortar battery, replaced the division's three regiments of three battalions each. The division's battle groups were:
Sources: en.wikipedia.org
TCM is said to be based on such texts as Huangdi Neijing (The Inner Canon of the Yellow Emperor), and Compendium of Materia Medica, a sixteenth-century encyclopedic work, and includes various forms of herbal medicine, acupuncture, cupping therapy, gua sha, massage (tui na), bonesetter (die-da), exercise (qigong), and dietary therapy. TCM is widely used in the Sinosphere. One of the basic tenets is that the body's qi is circulating through channels called meridians having branches connected to bodily organs and functions. There is no evidence that meridians or vital energy exist. Concepts of the body and of disease used in TCM reflect its ancient origins and its emphasis on dynamic processes over material structure, similar to the humoral theory of ancient Greece and ancient Rome. The demand for traditional medicines in China is a major generator of illegal wildlife smuggling, linked to the killing and smuggling of endangered animals. The Chinese authorities have engaged in attempts to crack down on illegal TCM-related wildlife smuggling.
==== Discovering supercivilizations ==== In the article On the Inevitability and the Possible Structure of Supercivilizations published in 1985, Kardashev evokes the possible scenarios and the means of investigation available to humanity for the detection of hypothetical extraterrestrial supercivilizations. The Soviet astronomer reminds us that we search for these supercivilizations on the basis of our own development criteria, and that predictions are possible only for extraterrestrial worlds close to our technological level, the others being beyond our intellectual representation. Nevertheless, it seems useful to him to conceive models of supercivilizations based at the same time on imagination and on our present scientific knowledge. Since the laws of physics are immutable, even if new laws are discovered in the future, they will not abolish those already known. According to Kardashev, theoretical models of supercivilizations must meet two basic assumptions. The first is that the range of supercivilization activities that obey the laws of physics is limited only by natural and scientific constraints, while the second is that the evolution of supercivilization activities cannot be interrupted or limited by intrinsic, inherent contingencies, such as large-scale social conflicts. For Kardashev, unlike other scientists, supercivilizations cannot self-destruct or retrogress.
An Indian study of seven bee species and nine plant species found 45 yeast species from 16 genera colonise the nectaries of flowers and honey stomachs of bees. Most were members of the genus Candida; the most common species in honey bee stomachs was Dekkera intermedia, while the most common species colonising flower nectaries was Candida blankii. Although the mechanism is not fully understood, it was found that A. indica flowers more if Candida blankii is present. In another example, Spathaspora passalidarum, found in the digestive tract of bess beetles, aids the digestion of plant cells by fermenting xylose. Many fruits produce different types of sugars that attract yeasts, which ferment the sugar and turns it into alcohol. Fruit eating mammals find the scent of alcohol attractive as it indicates a ripe, sugary fruit which provides more nutrition. In turn, the mammals helps disperse both the fruit's seeds and the yeast's spores. Yeast and small hive beetle have mutualistic relationship. While small hive beetle is attracted by the pheromone released by the host honeybee, yeast can produce a similar pheromone which have the same attractive effect to the small hive beetle. Therefore, yeast facilitates SHB's infestation if the beehive contains yeast inside.
==== Anti-inflammatory activity ==== Studies examining honokiol as a protective therapy against focal cerebral ischemia-reperfusion injury have identified a number of anti-inflammatory pathways. Neutrophil infiltration of injured tissues can cause further damage and issues with healing. In in vitro studies, honokiol reduced fMLP (N-formyl-methionyl-leucyl-phenylalanine) and PMA (phorbol-12-myristate-13-acetate) induced neutrophil firm adhesion which is an integral step for infiltration. Honokiol inhibits ROS production in neutrophils. Honokiol also blocks inflammatory factor production in glial cells through the inhibition on NF-κB activation. This mechanism is believed to suppress production of NO, tumor necrosis factor-α (TNF-α), and RANTES/CCL5.
There is a dose-dependent increase in the QT interval and the corrected QT interval (QTc). Because of this, many practitioners will initiate dofetilide therapy only on individuals under telemetry monitoring or if serial EKG measurements of QT and QTc can be performed.
Sources: en.wikipedia.org
Identity is confirmed by matching the retention time in reversed-phase chromatography against a reference standard and by measuring the molecular mass with mass spectrometry. Tandem mass spectrometry or amino acid analysis can verify the sequence of the seven residues. Because the peptide contains no aromatic amino acids, detection at 280 nm is not useful.
Lyophilized powder is normally stored desiccated at -20 °C, protected from light and moisture. Powder kept under these conditions is generally stable for long periods. Solutions are less stable and are usually prepared immediately before use.
A purity value from one chromatographic method does not capture every possible impurity. Related peptides with similar retention behavior, counterions, and residual solvents may not appear in the same analysis. Independent testing with an orthogonal method provides stronger assurance of identity and content.
Sealed, desiccated storage at -20 °C or colder is the standard recommendation for research-grade material. Vials should reach room temperature before they are opened, which limits condensation. Repeated temperature cycling is discouraged.