A practical reference on TP-7: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2026-02-28. Anything still debated is marked as such rather than presented as settled.
Measuring peptide exposure inside the brain is technically difficult. Selank is degraded rapidly in plasma, and assays must separate intact peptide from fragments, which favors targeted mass spectrometry over immunoassays alone. Reported half-lives are short, on the order of minutes, so effects observed hours later are attributed to downstream signaling rather than to the parent compound. Blood-brain barrier permeability is debated and rarely quantified directly. Gaps include absent dose-response characterization, inconsistent reporting of purity, and almost no pharmacokinetic data from human participants.
Selank is studied chiefly as an animal-model anxiolytic with proposed secondary effects on memory and immune signaling. Reported mechanisms include modulation of the GABA-A receptor complex, inhibition of enkephalin-degrading enzymes, and shifts in monoamine turnover within limbic structures. Some experiments describe increased expression of brain-derived neurotrophic factor in the hippocampus after repeated dosing. No single molecular target has been confirmed, and the peptide does not bind any receptor with the selectivity typical of a conventional small-molecule drug. Mechanism therefore remains a set of hypotheses rather than an established pathway.
Laboratory work relies on standard behavioral paradigms. Rodents are tested in the elevated plus maze, open field, and passive avoidance tasks, with outcomes compared against diazepam or vehicle controls. Intranasal dosing is used most often because it bypasses first-pass metabolism, though intraperitoneal and intravenous routes also appear in published protocols. Biochemical endpoints include tissue BDNF concentrations, cytokine levels, and monoamine metabolites. Human data are limited to small Russian trials reporting reduced anxiety scores; most were not prospectively registered, and few employed independent outcome assessment.
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.
| Property | Value | Notes |
|---|---|---|
| Principal proposed target | GABA-A receptor complex | Hypothesis derived mainly from animal pharmacology |
| Common behavioral assay | Elevated plus maze | Rodent test for anxiety-like behavior |
| Reported molecular marker | Hippocampal BDNF expression | Measured by immunoassay or mRNA quantification |
| Typical dosing route | Intranasal | Chosen to reduce first-pass metabolism |
| Reported plasma half-life | Minutes | Based on limited peptide stability data |
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.
Selank is a hydrophilic peptide and dissolves readily in water and in aqueous buffers. The lyophilised powder is typically a white to off-white solid. Because short peptides are prone to hydrolysis and oxidation, handling benefits from limiting exposure to heat, moisture and strong light. Working solutions are commonly prepared in sterile water or saline, and repeated freeze-thaw cycles are avoided to reduce aggregation and loss of activity. These practices reflect general laboratory convention rather than published stability specifications.
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.
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 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.
==== Marine algae ==== The factors affecting δD of algal lipids are: δD of water, algal species (up to 160%), lipid type (up to 170%), salinity (+0.9±0.2% per PSU), growth rate (0 ~ −30% per day) and temperature (−2 ~ −8% per °C). In a study by Zhang et al. (2009), the δDs of fatty acids in Thalassiosira pseudonana chemostat cultures were −197.3‰, −211.2‰ and −208.0‰ for C14, C16 and C18 fatty acids respectively. The δD of C16 fatty acid in the algae A. e. unicocca at 25°C, was determined using the empirical equation y = 0.890x − 91.730, where x is the δD of water at harvest. For another algal species, B. v. aureus, the equation was y = 0.869x − 74.651. The degree of D/H fractionation in most algal lipids increases with increasing temperature and decreases with increasing salinity. The growth rates have different impacts on the D/H fractionation depending on the species types.
=== Disputes with other politicians === In October 2023, Ford publicly stated that MPP Sarah Jama had a "long and well-documented history of antisemitism" and "hateful views", and that she "publicly support[ed] the rape and murder of innocent Jewish people," and called for her to resign. In response, Jama served Ford's office a cease and desist letter and threatened to sue him for libel. In April 2024, Doug Ford called for the reversal of the Speaker's ban on wearing keffiyeh in the legislature, which was imposed after an unidentified MPP complained about Sarah Jama donning a Palestinian keffiyeh at the start of the Gaza war. The motion to overrule the ban did not receive unanimous consent and remained in effect. In August 2026, it was reported that Ford's Progressive Conservative Party had sent a party official to follow Ontario Liberal Party leader Bonnie Crombie while she vacationed in Jamaica shortly after her election in 2023.
==== Removing yellowing from aged plastics ==== Hydrogen peroxide may be used in combination with a UV-light source to remove yellowing from white or light grey acrylonitrile butadiene styrene (ABS) plastics to partially or fully restore the original color. In the retrocomputing scene, this process is commonly referred to as retrobright.
The International Supply Chain Education Alliance (ISCEA) is a certifying body. Founded in 2003 and currently holding over 100,000 members, ISCEA has its World HQ office in Beachwood, OH, USA and regional offices in LATAM, EMEA and APAC. ISCEA is the governing body for the Ptak Prize. Besides Certified Supply Chain Manager (CSCM) certification, ISCEA has developed several professional certification programs that include: Certified Supply Chain Analyst (CSCA), Certified Lean Master (CLM), Certified RFID Supply Chain Manager (RFIDSCM), Certified Demand Driven Planner (CDDP), Certified HealthCare Supply Chain Analyst (CHSCA); and Certified Lean Six Sigma Yellow Belt (CLSSYB), Green Belt (CLSSGB) and Black Belt (CLSSBB).
Common treatments to remove contaminants include treatments with ethanol and formaldehyde, the latter of which is very common; ethanol solutions help remove compounds bonded to the alginate, and formaldehyde solutions help prevent enzymatic or microbial reactions. The algae is then treated with an acidic solution to help disrupt cell walls, which converts the alginate salts into insoluble alginic acid; a subsequently applied alkaline solution (pH 9-10), usually sodium carbonate, converts it back into water-soluble sodium alginate, which is then precipitated. It is also possible to extract the alginate directly with an alkaline treatment, but this is less common. Alginic acid is usually precipitated, through different techniques, with either an alcohol (usually ethanol), calcium chloride, or hydrochloric acid. After the alginin is precipitated into a fine paste, it is dried, ground to the desired grain size, and finally purified through a variety of techniques. Commercial alginate for biomedical and pharmaceutical use is extracted and purified through more rigorous techniques, but these are trade secrets.
Sources: en.wikipedia.org
Letsie I officially remained loyal to the Cape, while tacitly supporting the rebellion by confiscating land from Basuto loyalists and accepting Austen's severed head as a peace offering from Transkeian chief Tlokwa. According to Basuto oral tradition, Letsie I purposefully cultivated the image of a weak and unintelligent leader, while covertly communicating with the rebel leaders and encouraging the continuation of the rebellion. Basuto loyalist leaders like Jonathan Molapo surrendered their weapons on Letsie's orders so as to maintain control of the country in case the rebels were defeated. During the course of the war, Griffith continued to believe in Letsie's loyalty, blaming his inability to control his chiefs for the war. In January the outbreak of the First Boer War put further pressure on the Cape's already limited resources. By that time, the Cape war expenditure had reached £3 million. Fearing that Free State burghers might defect to the South African Republic, Cape authorities refused to allow new Boer volunteers to join the Basutoland campaign. The same month, the Basuto sued for peace with the assistance of opposition parliamentarian Jacobus Wilhelmus Sauer. As the maize harvest season neared, the Basuto began to fear that further fighting would lead to starvation in the following year. Under the terms put forward by the Basuto, they would retain their guns and autonomous rule.
The exception is the gasoline engine powered unit, which requires a much higher level of training and topside supervision for safe use. The air-line breathing air compressor compresses clean atmospheric air and stores it in a receiver tank, using an overpressure valve to limit the pressure. The air passes through a filter and the air hose to the diver's demand valve. Small 12 volt diaphragm compressors are used for recreational hookah, with a delivery of around 1.8 bars (26 psi), which severely limits the depth to which air can be supplied. The rubber diaphragm pump usually requires no oil lubricant and delivers oil-free air. Piston compressors for hookah deliver air at higher pressures, up to about 9 bars (130 psi), and are usually driven by a small 4-stroke petrol engine. They are usually oil lubricated, using a breathing air rated mineral or synthetic oil without toxic additives. This type of compressor requires a filter to clean the air before delivery to the diver. Delivery pressure for 12 metres (39 ft) is about 20 to 35 pounds per square inch (1.4 to 2.4 bar) using a hookah regulator. Depths of 40 metres (130 ft) require up to 9 bars (130 psi). The pressure relief valve will blow off excess air delivered at low demand, to protect the system from overpressure loads, while delivering sufficient air for higher exertion. The air line hose should be rated for breathing air, with a bore of 8 to 10 millimetres (0.31 to 0.39 in). It is usually buoyant to minimise snagging on the bottom, particularly if not tended from the surface.
==== DNAPL behavior in the saturated zone ==== The liquid phases of DNAPLs will continue to move vertically downward through the saturated zone until either their volume is exhausted by residual saturation or their path is intercepted by the layer of low permeability, at which point the DNAPLs will begin to migrate horizontally. if the lower permeability boundary is bowl-shaped, the DNAPL can form a pond-like reservoir. Contrarily, both the residually saturated and adsorbed DNAPL phases are relatively immobile and more difficult to remove. DNAPL movement in the saturated zone can also be influenced by anthropogenic activity, including unsealed boreholes and improperly sealed sampling holes and monitoring wells.
Most sequencing approaches use an in vitro cloning step to amplify individual DNA molecules, because their molecular detection methods are not sensitive enough for single molecule sequencing. Emulsion PCR isolates individual DNA molecules along with primer-coated beads in aqueous droplets within an oil phase. A polymerase chain reaction (PCR) then coats each bead with clonal copies of the DNA molecule followed by immobilization for later sequencing. Emulsion PCR is used in the methods developed by Marguilis et al. (commercialized by 454 Life Sciences), Shendure and Porreca et al. (also known as "polony sequencing") and SOLiD sequencing, (developed by Agencourt, later Applied Biosystems, now Life Technologies). Emulsion PCR is also used in the GemCode and Chromium platforms developed by 10x Genomics.
Sources: en.wikipedia.org
Intranasal administration predominates in both animal and human research because it avoids hepatic first-pass metabolism. Injectable and intraperitoneal routes appear in animal work mainly for comparison.
Behavioral endpoints include time spent in open arms of the elevated plus maze and avoidance latencies. Biochemical endpoints include BDNF concentration, cytokine levels, and monoamine metabolite ratios in brain tissue.
Most published studies are small, originate from a limited number of laboratories, and lack independent replication. Dose-response relationships, measured brain exposure, and long-term outcomes are not well characterized.
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.