The short version of reverse-phase HPLC fits in a sentence. The long version — which is the one that helps — is below.
This page was last updated on 2026-08-01 and is reviewed periodically as new material appears.
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.
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.
Lyophilized material is generally stable for extended periods when kept dry at or below minus twenty degrees Celsius. Working solutions are less stable, and common practice is to aliquot and freeze them so that repeated freeze-thaw cycles are avoided. Aqueous solutions are sensitive to pH extremes and to microbial growth, so short-term storage at refrigerator temperature is typical. Oxidation and hydrolysis are the principal degradation routes. Reconstitution with sterile water or a mild buffer is standard, and solutions should be protected from light.
Regulatory treatment varies by jurisdiction. In Russia the compound is a registered prescription product, while in the European Union and the United States it is generally handled as a research chemical without a marketing authorization. Suppliers therefore operate outside pharmaceutical oversight, and buyers rely on supplier documentation for purity and identity claims. Chain of custody and third-party testing are the main verification tools. Analysts note that the absence of a pharmacopoeial monograph for research-grade material limits standardization across vendors.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide | Tuftsin analogue |
| Sequence | Thr-Lys-Pro-Arg-Pro-Gly-Pro | Single-letter form: TKPRPGP |
| Molecular formula | C33H57N11O9 | Calculated for the free peptide |
| Molecular weight | About 751.9 g/mol | Derived from the sequence |
| Appearance | White to off-white powder | Typical lyophilised form |
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.
Development took place at the Institute of Molecular Genetics of the Russian Academy of Sciences, where a series of short peptides were designed in the 1980s and 1990s. Selank was selected from variants of tuftsin that showed resistance to plasma peptidases. Russian regulatory approval covers it as an anxiolytic agent given intranasally. Outside that market the compound is normally handled as a research chemical rather than a medicine, and no widely recognised international pharmacopoeial monograph exists. The name Selank is a coined trade designation rather than a systematic chemical name.
Enzymatic stability motivates the extra three residues at the carboxyl end. Native tuftsin is cleaved quickly by circulating aminopeptidases and carboxypeptidases, which limits its duration of action and its usefulness as a tool compound. Extending the chain with proline-rich segments is a common design tactic because proline constrains the backbone and slows proteolysis. The same Pro-Gly-Pro motif appears in other Russian-developed peptides of the era. Whether the full seven-residue chain is required for activity, or whether it acts mainly as a prodrug releasing tuftsin, remains unresolved.
Mephedrone and the cathinones marked somewhat of a turning point for designer drugs, turning them from little known, ineffective substances sold in head shops to powerful substances able to compete with classical drugs on the black market. Mephedrone especially experienced a somewhat meteoric rise in popularity in 2009 and the resulting media panic resulted in its prohibition in multiple countries. Following this there was a considerable emergence of other cathinones which attempted to mimic the effects of mephedrone, and with a newly attracted customer base, plenty of money to drive innovation. Subsequently, the market rapidly expanded, with more and more substances being detected every year. In 2009, the EMCDDA's early warning system discovered 24 new drugs. In 2010, it found another 41; in 2011, another 49; and in 2012, there were 73 more. In 2013, a further 81 were identified: a total of 268 new drugs in just four years. These have not been limited to cathinones, with 35% being cannabinoids and the rest being composed of stimulants, benzodiazepines, psychedelics, dissociatives and to a lesser extent, every other class of drugs, even ibogoids and nootropics. The largest group of drugs being monitored by the EMCDDA is synthetic cannabinoids, with 209 different synthetic cannabinoids reported between 2008 and 2021 - including 11 new cannabinoids identified for the first time in 2020.
Aldehyde dehydrogenase, mitochondrial is an enzyme that in humans is encoded by the ALDH2 gene located on chromosome 12. ALDH2 belongs to the aldehyde dehydrogenase family of enzymes. Aldehyde dehydrogenase is the second enzyme of the major oxidative pathway of alcohol metabolism. ALDH2 has a low Km for acetaldehyde, and is localized in mitochondrial matrix. The other liver isozyme, ALDH1, localizes to the cytosol. Most White people have both major isozymes, while approximately 36% of East Asians have the cytosolic isozyme but not a functional mitochondrial isozyme. As of 2023, it is estimated that as many as 709 million people (8.8% of the global population) carry the ALDH2*2 (E504K) mutation. A remarkably higher frequency of acute alcohol intoxication among East Asians than among Whites could be related to this absence of a catalytically active form of ALDH2. The increased exposure to acetaldehyde in individuals with the catalytically inactive form may also confer greater susceptibility to many types of cancer.
The mass violence of the sans-culottes created a lasting impact during the Reign of Terror. These revolutionaries allied themselves most readily with those in power who promised radical change. The sans-culottes believed in a complete upheaval of the government, pushing for the execution of any that were considered corrupt by the leaders, even going as far as wanting "the enemies of the republic [to] hang-main and the guillotine to stand like the first patriots, the finisher of the law." The support of the sans-culottes could be used as a political weapon to get rid of enemies of the Revolution. The key to Robespierre's Terror lay in their willingness and ability to mobilize. Thus, the Committee leaders used speeches to gain their support. In a speech On the Principles of Political Morality. Robespierre proclaimed: "It has been said that terror was the mainspring of despotic government. Does your government, then, resemble a despotism? Yes, as the sword which glitters in the hands of liberty's heroes resembles the one with which tyranny's lackeys are armed." Robespierre expressed a desire for liberty that the sans-culottes admired. They pushed the committee for radical changes and often found a voice with Robespierre.
=== Weight loss and regain === As of 2007, there was no evidence showing that weight loss is directly correlated with ingesting capsaicin. Well-designed clinical research had not been performed because the pungency of capsaicin in prescribed doses under research prevented subjects from complying in the study. A 2014 meta-analysis of further trials found weak evidence that consuming capsaicin before a meal might slightly reduce the amount of food consumed, and might drive food preference toward carbohydrates.
Sources: en.wikipedia.org
=== 13 August === Three people were killed in an RSF drone strike on an event organized by the Sudan Shield Forces in Tambul, Gezira State. The RSF accused the SAF of carrying out an airstrike that destroyed the Ministry of Urban Planning building in Ed Daein and injured several people.
The Research Quality Association (RQA) is a not for profit membership association. Formerly known a Quality Assurance Group UK (QAG UK) and the British Association of Research Quality Assurance (BARQA), the association changed its name to RQA in December 2012 in order to be able to act in a more global role.
In contrast to LAPs, where cyclodehydration occurs via the action of two distinct proteins responsible for leader peptide binding and cyclodehydrative catalysis, these are fused into a single protein (G protein) in cyanobactin and thiopeptide biosynthesis. However, in thiopeptides, an additional protein, designated the Ocin-ThiF-like protein (F protein) is necessary for leader peptide recognition and potentially recruiting other biosynthetic enzymes.
== History == Martin Freund and (Jakob) Edmund Speyer of the University of Frankfurt in Germany published the first synthesis of oxycodone from thebaine in 1916. When Freund died, in 1920, Speyer wrote his obituary for the German Chemical Society. Speyer, born to a Jewish family in Frankfurt am Main in 1878, became a victim of the Holocaust. He died on 5 May 1942, the second day of deportations from the Lodz Ghetto; his death was noted in the ghetto's chronicle. The first clinical use of the drug was documented in 1917, the year after it was first developed. It was first introduced to the U.S. market in May 1939. In early 1928, Merck introduced a combination product containing scopolamine, oxycodone, and ephedrine under the German initials for the ingredients SEE, which was later renamed Scophedal (SCOpolamine, ePHEDrine, and eukodAL) in 1942. It was last manufactured in 1987 but can be compounded. This combination is essentially an oxycodone analogue of the morphine-based "twilight sleep", with ephedrine added to reduce circulatory and respiratory effects. The drug became known as the "Miracle Drug of the 1930s" in Continental Europe and elsewhere and it was the Wehrmacht's choice for a battlefield analgesic for a time. The drug was expressly designed to provide what the patent application and package insert referred to as "very deep analgesia and profound and intense euphoria" as well as tranquillisation and anterograde amnesia useful for surgery and battlefield wounding cases.
Daptomycin, sold under the brand name Cubicin among others, is a lipopeptide antibiotic used in the treatment of systemic and life-threatening infections caused by Gram-positive organisms. Daptomycin was removed from the World Health Organization's List of Essential Medicines in 2019. The World Health Organization classifies daptomycin as critically important for human medicine.
Sources: en.wikipedia.org
The sequence is Thr-Lys-Pro-Arg-Pro-Gly-Pro, commonly written as TKPRPGP. It shares the first four residues with tuftsin and carries three prolines in the chain. The proline-rich tail is the main structural feature that separates it from the parent tetrapeptide.
Selank is a synthetic analogue built on the tuftsin tetrapeptide Thr-Lys-Pro-Arg. Extra proline residues were added to the C-terminus during design work. That modification is intended to make the peptide less vulnerable to rapid enzymatic degradation.
Transliteration from Russian produces variant spellings such as Selanc. Many suppliers avoid the trade-style name entirely and list the peptide sequence. Comparing sequences rather than names is the reliable way to confirm two entries describe the same molecule.
Purity is usually reported as an HPLC area percentage, most often measured at 214 nm. Identity is confirmed separately by mass spectrometry. A certificate of analysis should state both the method and the observed value.