TP-7 raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
This page was last updated on 2025-08-11 and is reviewed periodically as new material appears.
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.
Dry powder is normally held at -20 degrees Celsius or lower, in a sealed container with desiccant and protection from light. Reconstituted solutions are usually kept at 2 to 8 degrees Celsius for short periods and frozen for longer ones. Proline residues at several positions are generally associated with some resistance to peptidase attack, but chemical stability still declines at neutral to alkaline pH and at elevated temperature. Exact shelf-life figures are product-specific and are not standardised across suppliers.
Identity and purity are usually assessed by reversed-phase high-performance liquid chromatography, with mass spectrometry used to confirm molecular mass and sequence information. Amino acid analysis and peptide mapping may supplement these methods. Certified reference standards are scarce, and many commercial lots are sold as research chemicals without a pharmacopoeial monograph. Regulatory treatment differs by country: Selank is a registered prescription medicine in Russia, while in the European Union and the United States it is not an approved drug and may fall under research-chemical or unapproved-product frameworks.
| 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 |
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 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.
Published work on this peptide almost always uses intranasal delivery, with drops or a spray applied to the nasal mucosa. Some animal experiments have used subcutaneous or intraperitoneal injection, and a smaller number have compared routes directly. Oral administration is not a focus of the literature, because short peptides of this size are broken down by digestive enzymes and cross intestinal barriers poorly. How much of an intranasal dose reaches the bloodstream intact in humans remains an open question.
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.
Leisure activities were found to have the largest impact on individuals because these activities were the most self-directed of the three domains, as adolescents had the choice of activity, and were more likely to be able to align it with their true selves. The study found that subjective experiences were more important than the activities themselves and that adolescents reported higher levels of well-being. They reported that when adolescents express themselves through self-defining activities across multiple domains, they have a clearer image of themselves, of what they want to achieve and higher wellness. Goal-setting was found to be a unique predictor; when adolescents work towards goals set by themselves and accomplish them, they are likely to have a clearer emerging identity and higher well-being. Researchers found that more adolescents were happy when they were involved in self-chosen activities because the activities were chosen in line with their true self.
=== Movement of NAPLs in the unsaturated zone === The unsaturated zone involves a porous media which consists of small particles, around which exist a thin film of water which acts as a membrane. The rest of the space between these particles consists of air. Thus, NAPLs can either remain as an immiscible hydrocarbon, dissolve into water, adsorb onto solid porous material, or vaporize into gaseous form. This four-phase model is highly variable and can even change within a particular site during different stages of site remediation. As such, it is important to continuously monitor the phase distribution on a case-by-case basis. Each of these phases differs in terms of their mobility and their available remediation techniques. The most mobile phases of NAPL are the volatilized/gaseous phase and the solubilized/aqueous phase, while the least mobile phases of NAPL are the adsorbed/solid phase and the immiscible liquid phase. Because of these complexities, flow is more difficult to measure in the unsaturated zone than in the saturated zone. Contamination of the unsaturated zone is dangerous because of both the potential to seep into the saturated zone, where aquifers are contained, and the potential to harm ecological life. Whether or not the NAPL reaches the saturated zone is determined by a parameter called residual saturation. Residual saturation is caused by capillary action, which immobilizes NAPLs and restricts their infiltration into the saturated zone.
Loop diuretics: furosemide, bumetanide, torsemide, ethacrynic acid Thiazide diuretics: chlorothiazide, hydrochlorothiazide Thiazide-like diuretics: metolazone, indapamide, chlorthalidone Potassium-sparing diuretics: amiloride, triamterene, spironolactone, eplerenone For loop diuretics, thiazide diuretics and thiazide-like diuretics, their common side effects include hypokalemia, hyponatremia, metabolic alkalosis and hyperglycaemia. For potassium-sparing diuretics, its common side effects include hyponatremia, hyperkalemia, metabolic acidosis and sexual dysfunction specifically for spironolactone. The use of diuretics should be avoided in patients with severe dehydration, anuria (absence of urine production). Diuretics are contraindicated in cases of severe electrolyte abnormalities and should not be administered until an electrolyte balance is restored. Special attention should be given to the use of thiazide and loop diuretics as they may exacerbate diabetes and gout.
==== Withdrawn ==== Kyle Sinclair, former vice chair of the Bexar County Republican Party, candidate for the 28th district in 2024 and nominee for the 20th district in 2022 (remained on ballot, endorsed Teixeira)
Sources: en.wikipedia.org
== Related technologies == Other devices to deliver inhaled nicotine have been developed. They aim to mimic the ritual and behavioral aspects of traditional cigarettes. British American Tobacco, through their subsidiary Nicoventures, licensed a nicotine delivery system based on existing asthma inhaler technology from UK-based healthcare company Kind Consumer. In September 2014 a product based on this named Voke obtained approval from the United Kingdom's Medicines and Healthcare Products Regulatory Agency. In 2011, Philip Morris International bought the rights to a nicotine pyruvate technology developed by Jed Rose at Duke University. The technology is based on the chemical reaction between pyruvic acid and nicotine, which produces an inhalable nicotine pyruvate vapor. Philip Morris Products S.A. created a different kind e-cigarette named P3L. The device is supplied with a cartridge that contains nicotine and lactic acid in different cavities. When turned on and heated, the nicotine salt called nicotine lactate forms an aerosol.
Inflammation of the fetal membranes is called chorioamnionitis. Balanced inflammation is an important factor in maintaining fetal membranes by regulating the remodeling. However, if the inflammatory response increases above this level it can have dangerous and potentially fatal effects for the mother and child. These elevated levels of inflammatory molecules in the fetal membrane is called 'sterile inflammation'. Sterile inflammation can be caused by both microbial infection and non-infectious factors, such as senescence of fetal membranes. Senescence is associated with the aging of actively cycling and dividing cells. As the fetal membrane cells proliferate during remodelling, the telomeres (short length or non-coding DNA on the end of chromosomes that protect essential coding DNA from degradation during replication) shorten as chromosomes can not be copied end-to-end fully. Once the telomeres have reached a critical length the cell can no longer divide and can hence cause telomere-dependent replicative senescence. This should occur naturally at term (37 weeks), as it is an important factor to increase the inflammatory environment in the uterus to initiate parturition. However, fetal membrane senescence can be accelerated by oxidative stress and hence, stimulate sterile inflammation to occur prior to term; consequently, causing preterm birth.
However, the result of the fight was overturned to a No Contest and Casey was suspended for three months by the Texas Department of Licensing and Regulation after an in-competition sample provided by Casey was found to have an elevated testosterone to epi-testosterone ratio. Several experts questioned the findings and in June 2017 she was exonerated by the UFC after follow up testing showed no evidence of doping. On June 29 the UFC issued a strongly worded statement requesting that "the Texas Department of Licensing and Regulation (TDLR) immediately reverse its ruling and exonerate Cortney of any wrongdoing". In turn, on June 30, the TDLR lifted Casey's three-month suspension and reinstated her victory. Casey faced Felice Herrig on December 2, 2017 at UFC 218. She lost the bout via split decision. Casey fought against Michelle Waterson at UFC on Fox 29 in Glendale, AZ on April 14. Cortney lost the fight via split decision Casey faced Angela Hill on August 25, 2018 at UFC Fight Night 135. She won the fight via split decision. Casey next faced Cynthia Calvillo on February 17, 2019 at UFC on ESPN 1. She lost the fight by unanimous decision. Casey was expected to face Virna Jandiroba on December 7, 2019 at UFC on ESPN 7. However, Casey withdrew from the event for an undisclosed reason and she was replaced by Lívia Renata Souza Casey was scheduled to face Lara Procópio on May 16, 2020 at UFC Fight Night 175 (San Diego).
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.
Dry powder is normally held at -20 degrees Celsius or below in a sealed, light-protected container with desiccant. Brief room-temperature handling during weighing is generally tolerated. Storage instructions vary between suppliers, so the accompanying certificate of analysis should be followed.