A practical reference on Selank: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2025-12-11. Anything still debated is marked as such rather than presented as settled.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Typical purity specification | 95 percent or higher by RP-HPLC | Area percentage of the main peak |
| Identity confirmation | Electrospray ionization mass spectrometry | Observed mass compared with the theoretical value near 751.9 Da |
| Recommended dry storage | -20 °C, desiccated | -80 °C for multi-year archival material |
| Solution handling | Prepare fresh; avoid long storage | Sterile filtration reduces microbial load |
| Common synonyms | TKPRPGP; TP-7 | Sequence code and laboratory designation used interchangeably |
Published clinical evidence is limited. Most controlled trials were conducted in Russia, enrolled modest numbers of participants, and appeared in Russian-language journals, which restricts independent verification. Reported outcomes include lower anxiety scores, improved attention and memory measures, and changes in fatigue ratings. Reviews written in English note methodological limitations such as small samples and inconsistent endpoints. Whether the compound produces clinically meaningful benefit relative to established anxiolytics is therefore an open question rather than an established finding.
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro. It was designed at the Institute of Molecular Genetics of the Russian Academy of Sciences as a structural analogue of tuftsin, a naturally occurring tetrapeptide fragment of the immunoglobulin heavy chain. The added Pro-Gly-Pro tail was intended to slow enzymatic degradation and extend biological activity. In Russia it is registered as an anxiolytic nasal preparation, while regulators elsewhere have not approved it for clinical use.
Quality assessment of Selank samples typically combines purity determination with identity confirmation and counter-ion analysis. Purity is usually reported as a percentage by chromatographic area, with values above 95 percent often quoted for research-grade material. Water content and residual solvents are checked in lyophilized batches because they affect both stability and accurate mass determination. A reported purity figure does not by itself establish that a sample is the intended sequence, so orthogonal methods are needed to rule out sequence isomers or truncation products.
Characterization of Selank in laboratory settings relies on standard peptide analytical techniques. Reverse-phase high-performance liquid chromatography separates the peptide from related impurities and degradation products, while mass spectrometry confirms molecular identity through accurate mass measurement. Amino acid analysis and peptide sequencing verify the primary structure when reference material is unavailable. Because Selank is a short chain, fragmentation-based analysis produces a diagnostic ion pattern that supports confident identification.
Peptide stability depends strongly on temperature, moisture, and pH. Lyophilized Selank is generally most stable when stored cold and dry, with freezer temperatures commonly used for long-term storage. In solution, the compound is susceptible to hydrolysis and to microbial growth if it is not handled aseptically. The C-terminal proline-rich extension appears to slow enzymatic cleavage relative to tuftsin, though quantitative degradation rates vary with the matrix and the conditions tested. Published stability data specific to Selank remain sparse.
Development work on the compound began in the 1980s and 1990s at the Institute of Molecular Genetics in Moscow, within the same research programme that produced the peptide Semax. Early investigators sought a tuftsin derivative with improved resistance to enzymatic breakdown and with activity in the central nervous system after peripheral administration. Most of the primary literature from this period was published in Russian, a factor that still shapes how easily the findings can be checked by outside groups.
Naming for this compound is not fully standardised in English sources. The spelling Selanc appears in some transliterations, and catalogue entries may instead list the peptide sequence itself as the identifier. Reference material sometimes groups it with other short synthetic peptides studied for behavioural effects, which can create confusion when citations are compared. Distinguishing the exact sequence from related tuftsin analogues is therefore a practical first step when reviewing any dataset or specification sheet.
Selank is a synthetic heptapeptide with the sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro, frequently abbreviated as TKPRPGP. It was designed as a structural analogue of tuftsin, a naturally occurring tetrapeptide released by enzymatic cleavage of the immunoglobulin heavy chain. The two additional proline residues at the C-terminal end extend the parent chain and change how the molecule behaves in solution. The free peptide has a calculated molecular mass of approximately 751.9 g/mol and is generally supplied as a lyophilised white to off-white powder.
== See also == Animal nutrition Gerontology Insulin (medication) Pasteur's quadrant Senescence Technology transfer The Australian Journal of Experimental Biology and Medical Science Xenotransplantation
== History == In 1819, after the Treaty of Singapore was signed on 6 February and modern Singapore was born, Sir Stamford Raffles declared a policy that all forms are gambling are prohibited. However, the first Resident of Singapore, William Farquhar, established a gambling farm which frustrated Raffles, one of the many reasons leading to Raffles' removal of Farquhar as resident of Singapore. In 1823, after removing Farquhar, Raffles published a Regulation which banned gaming houses and cockfighting pits. Gamblers and owners of gaming houses and cockfighting pits would be punished with 80 blows with a cudgel, gaming stakes confiscated, gaming house confiscated and to wear a heavy wooden collar for a month. However, Farquhar's replacement, John Crawfurd, wrote to the Supreme Government advocating licensing gambling in Singapore and that the Chinese community had appealed to him to suspend Raffle's regulation. Licensed gambling continued to flourish under Crawfurd's governance with gambling profits doubled from 15,000 to 30,000 pounds from 1823 to 1826. In 1827, the Grand Jury made a presentation against gaming farms, Crawfurd referred them as "idiots". Gambling farms were frequently debated in the following years such that in the 1860s, the Secretary of State for the Colonies, Henry Pelham-Clinton, 5th Duke of Newcastle, launched an inquiry over the gambling farms. In 1842, the Singapore Sporting Club was founded by Scottish merchant William Henry Macleod Read to operate the Serangoon Road Race Course at Farrer Park Field.
Islam dominates in Pakistan, with about 96.35% of the population being Muslim. Pakistan ranks second globally in Muslim population, and is home to 10.5% of the world's Muslims. Karachi is the largest Muslim city in the world. The majority follow Sunni Islam, with a significant presence of Sufism, while Shia Muslims constitute a minority. Shias represent between 5–25%. The Shia population in Pakistan was estimated at 42 million in 2019. As of 2012, 12% of Pakistani Muslims self-identify as non-denominational Muslims. The Ahmadis are a minority, officially considered non-Muslims. Ahmadis face persecution, banned from calling themselves Muslims since 1974.
Due to use of the drug for date rape and recreation, in 1998 Roche modified the formulation to give lower doses, make it less soluble, and add a blue dye for easier detection in drinks. It was never marketed in the United States, and by 2016 had been withdrawn from the markets in Spain, France, Norway, Germany, and the United Kingdom.
==== Golf ==== The university's golf teams have also been notably successful. The men's team won a national championship in 1992 (NCAA Division I Men's Golf Championships), and has produced a number of successful professionals, most notably Jim Furyk. The women's team won national championships in 1996, 2000 and 2018 (NCAA Women's Golf Championship). The women's golf program has produced professionals Annika Sörenstam, Lorena Ochoa, and Erica Blasberg.
Sources: en.wikipedia.org
Marketers use well-researched techniques to try to control purchasing behavior. The layout of a supermarket is considered by some to consist of a few rules of thumb and three layout principles. The high-draw products are placed in separate areas of the store to keep drawing the consumer through the store. High impulse and high margin products are placed in the most predominant areas to grab attention. Power products are placed on both sides of the aisle to create increased product awareness, and end caps are used to receive a high exposure of a certain product whether on special, promotion or in a campaign, or a new line. The first principle of the layout is circulation. Circulation is created by arranging product so the supermarket can control the traffic flow of the consumer. Along with this path, there will be high-draw, high-impulse items that will influence the consumer to make purchases which they did not originally intend. Service areas such as restrooms are placed in a location which draws the consumer past certain products to create extra buys. Necessity items such as bread and milk are found at the rear of the store to increase the start of circulation. Cashiers' desks are placed in a position to promote circulation. In most supermarkets, the entrance will be on the right-hand side because some research suggests that consumers who travel in a counter-clockwise direction spend more. However, other researchers have argued that consumers moving in a clockwise direction can form better mental maps of the store leading to higher sales in turn.
=== May === May 5, 2011: Portugal Portugal's Minister of Finance Teixeira dos Santos warns that the upcoming bail-out package of €78 billion is expected to shift Portugal into recession for at least 2 years.
==== Rotary jet spinning ==== Rotary jet spinning is a technique used in the production of biotextiles, which involves the extrusion of polymer solutions or melts through a rapidly rotating spinneret. As the polymer solution or melt exits the spinneret, it is subjected to centrifugal forces, forming fine fibers. These fibers are collected to create a nonwoven fabric or scaffold structure suitable for various biomedical applications. Rotary jet spinning offers advantages such as producing highly porous structures with controllable fiber diameter and alignment, making it promising for tissue engineering and drug delivery applications in biomedicine.
Using only the egg yolk. Using specialized devices to whip the egg, particularly the egg white into a meringue-like foam before pouring over the rice. A cooking toy called the Kyūkyoku no TKG (Ultimate TKG) was marketed by Takara Tomy Arts in 2017 specifically for this purpose.
The introduction of the F gene of SeV in the form of a plasmid into the tumor tissue in mice by electroporation showed that the expression of the F gene increases the T cell infiltration of the tumor with CD4+ and CD8+ cells and inhibits tumor growth. It was also shown in other similar experiments that cancer cells themselves, transfected with plasmids that encode viral membrane glycoproteins with fusion function, cause the collective death of neighboring cells forming syncytium with them. Recruitment of bystander cells into the syncytium leads to significant regression of the tumor.
Sources: en.wikipedia.org
== Further reading == Watkins, Steve (29 June 2018). "Which Cincinnati public company CEO delivers the best bang for the buck? (Video)". Cincinnati Business Courier. American City Business Journals. Retrieved 31 Aug 2019. It's rare to see a CEO make less money than a CFO or an executive vice president. But that's how it worked last year at Medpace Holdings Inc....
Protein design is the rational design of new protein molecules to design novel activity, behavior, or purpose, and to advance basic understanding of protein function. Proteins can be designed from scratch (de novo design) or by making calculated variants of a known protein structure and its sequence (termed protein redesign). Rational protein design approaches make protein-sequence predictions that will fold to specific structures. These predicted sequences can then be validated experimentally through methods such as peptide synthesis, site-directed mutagenesis, or artificial gene synthesis. Rational protein design dates back to the mid-1970s. Recently, however, there were numerous examples of successful rational design of water-soluble and even transmembrane peptides and proteins, in part due to a better understanding of different factors contributing to protein structure stability and development of better computational methods.
=== Pharmacokinetics === Little information thus far has been published on the clinical pharmacokinetics of phenibut. The drug is reported to be well-absorbed. It distributes widely throughout the body and across the blood–brain barrier. Approximately 0.1% of an administered dose of phenibut reportedly penetrates into the brain, with this said to occur to a much greater extent in young people and the elderly. Following a single 250 mg dose in healthy volunteers, its elimination half-life was approximately 5.3 hours and the drug was largely (63%) excreted in the urine unchanged. Some limited information has been described on the pharmacokinetics of phenibut in recreational users taking much higher doses (e.g., 1–3 grams) than typical clinical doses. In these individuals, the onset of action of phenibut has been reported to be 2 to 4 hours orally and 20 to 30 minutes rectally, the peak effects are described as occurring 4 to 6 hours following oral ingestion, and the total duration for the oral route has been reported to be 15 to 24 hours (or about 3 to 5 terminal half-lives).
== External links == Zostavax Product Page U.S. Food and Drug Administration (FDA) Shingrix Product Page U.S. Food and Drug Administration (FDA) "Shingrix Vaccine Information Statement". U.S. Centers for Disease Control and Prevention (CDC). 15 January 2025. "Zostavax (Herpes Zoster Vaccine) Questions and Answers". Questions about Vaccines. U.S. Food and Drug Administration (FDA). 18 February 2021. Clinical trial number NCT02723773 for "A Long-term Follow-up Study (ZOE-LTFU) of Two Studies 110390 (ZOSTER-006) and 113077 (ZOSTER-022) to Assess the Efficacy, Safety, and Immunogenicity Persistence of GSK Biologicals' Herpes Zoster Subunit (HZ/su) Vaccine and Assessment of 1 or 2 Additional Doses in Two Subgroups of Older Adults" at ClinicalTrials.gov
=== Policy === Since the mid-1980s pharmaceutical companies have invested in medications for cancer or chronic disease that have greater potential to make money and have "de-emphasized or dropped development of antibiotics". On 20 January 2016 at the World Economic Forum, "80 pharmaceutical and diagnostic companies" called for "transformational commercial models" at an international level to spur research and development on antibiotics and on the use of diagnostic tests. A number of countries are considering or implementing delinked payment models for new antimicrobials whereby payment is based on value rather than volume of drug sales. This offers the opportunity to pay for valuable new drugs even if they are reserved for use in relatively rare drug resistant infections.
Sources: en.wikipedia.org
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.
A reported purity value reflects the share of the main peak in one chromatographic run and says nothing about identity. Confirming that the expected sequence is present requires a separate measurement such as mass spectrometry. Purity and identity are distinct questions.
A mass spectrum reports the molecular masses present in a sample and shows whether they match the value expected for selank, near 751.9 Da. It also flags common artifacts such as truncation or adduct formation. It does not establish correct stereochemistry or complete sequence order on its own.
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.