If you have been reading about lyophilization and want a single page that covers the useful parts, this is it: definitions, context, how it is studied, and the questions that come up repeatedly.
Last reviewed on 2025-09-01. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Common route | Intranasal | Also injected in some animal work |
| Solubility class | Freely soluble in water | Solid form is hygroscopic |
| Typical storage | About -20 degrees Celsius | Keep desiccated and dark |
| Purity method | Reverse-phase HPLC | Reported as area percent |
| Confirmatory method | Mass spectrometry | Verifies expected molecular mass |
Proposed mechanisms centre on the GABAergic system. Animal and tissue studies report changes in GABA-A receptor expression and reduced activity of GABA transaminase, the enzyme that degrades GABA. Effects on monoamine turnover, including serotonin and dopamine pathways, are also described, and a separate line of work links the peptide to increased expression of brain-derived neurotrophic factor in hippocampal tissue. Most of these findings come from rodent models and cell preparations. How the individual observations combine into a single coherent mode of action is not settled.
Pharmacokinetic data are sparse and largely derived from animal work. After intranasal administration the peptide appears in plasma within minutes, and reported half-lives are short, on the order of minutes to tens of minutes. Degradation proceeds through ordinary proteolytic cleavage into constituent amino acids and smaller fragments. Direct evidence that intact Selank reaches brain tissue in meaningful amounts is limited, and the extent of blood-brain barrier penetration is debated. Some authors argue that fragments, not the parent peptide, carry much of the observed activity.
Published clinical work is concentrated in Russian-language journals and generally involves small samples without independent replication. Systematic reviews in English note the shortage of randomised, placebo-controlled trials and the difficulty of verifying methods from translated reports. Outcome measures vary between studies, which complicates pooling of results. Interest in the compound as a cognitive or anxiolytic agent therefore rests on a thinner evidence base than the volume of citations suggests. Replication in well-powered trials with preregistered endpoints would be needed before firm conclusions about efficacy can be drawn.
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.
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.
Purity assessment relies mainly on reverse-phase high-performance liquid chromatography with ultraviolet detection. Because the peptide lacks a strong chromophore, detection often uses backbone absorbance near 214 nm. Identity is confirmed by mass spectrometry, typically electrospray ionization or matrix-assisted laser desorption, comparing the measured mass against the expected value. Amino acid analysis can verify composition after acid hydrolysis. Diastereomer content and residual counterions are reported less often, although both can influence biological assays.
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.
== Etymology == The term forensic stems from the Latin word, forēnsis (3rd declension, adjective), meaning "of a forum, place of assembly". The history of the term originates in Roman times, where many judicial processes, such as trials and preliminary hearings, were held in the forum. This origin is the source of the two modern usages of the word forensic—as a form of legal evidence; and as a category of public presentation. In modern use, the term forensics is often used in place of "forensic science". The word "science", is derived from the Latin word for 'knowledge' and is today closely tied to the scientific method, a systematic way of acquiring knowledge. Taken together, forensic science means the use of scientific methods and processes for crime solving.
OHPH, also known as hydroxyprogesterone enanthate (OHPE), as well as 17α-hydroxyprogesterone heptanoate or 17α-hydroxypregn-4-ene-3,20-dione 17α-heptanoate, is a synthetic pregnane steroid and a derivative of progesterone and 17α-hydroxyprogesterone. It is a progestogen ester; specifically, it is the C17α heptanoate (enanthate) ester of 17α-hydroxyprogesterone. Analogues of OHPH include the more well-known medications hydroxyprogesterone acetate and hydroxyprogesterone caproate (hydroxyprogesterone hexanoate). The C3 benzilic acid hydrazone of OHPH, hydroxyprogesterone heptanoate benzilic acid hydrazone (OHPHBH), is known and has been studied in animals. In terms of chemical structure, OHPH is very similar to hydroxyprogesterone caproate, differing from it only in having one additional carbon in its fatty acid ester chain.
thio-phosphorylated derivatives of resorcinols and calixarenes; studying thio-phosphorylated unsaturated compounds using petrochemical and wood-chemical feedstock; generation and theoretical study of phosphabetains and their derivatives (phosphonium salts, carboxyl-containing metal complexes); searching for liquid growth-boosting fertilizer compounds based on microelements. The following majors are currently offered to students: 04.03.01 Chemistry, Bachelor's degree program; 04.05.01 Fundamental and Applied Chemistry, Specialist Degree program; 04.04.01 Chemistry, Master's degree program; 44.03.01 Pedagogical Education, Bachelor's degree program. The following master's degree programs are offered by the Institute in the academic year 2015–2016:
Abbreviations for predicted unobserved decay: α for alpha decay, B for beta decay, 2B for double beta decay, E for electron capture, 2E for double electron capture, IT for isomeric transition, SF for spontaneous fission, * for the nuclides whose half-lives have lower bound. Predicted double beta decay has only been listed when beta decay is not also possible. (This does not apply to zirconium-96, which has been observed to decay both ways.) ^ Tantalum-180m is a "metastable isotope", meaning it is an excited nuclear isomer of tantalum-180. See isotopes of tantalum. However, the half-life of this nuclear isomer is so long that it has never been observed to decay, and it thus is an "observationally stable" primordial nuclide, a rare isotope of tantalum. This is the only nuclear isomer with a half-life so long that it has never been observed to decay. It is thus included in this list. ^^ Bismuth-209 was long believed to be stable, due to its half-life of 2.01×1019 years, which is more than a billion times the age of the universe. § Europium-151 and samarium-147 are primordial nuclides with very long half-lives of 4.62×1018 years and 1.066×1011 years, respectively.
Sources: en.wikipedia.org
==== 2010-2012 ==== Georgian analyst Ghia Nodia wrote that since the report did not find the Georgian attack on Tskhinvali as justified, "This has strengthened the impression that Georgia started the war and that the Georgian president was prone to reckless actions. This was a serious victory for Russia, since Russia can ignore criticism from the West, but Georgia cannot." John B. Dunlop concluded that the EU report would conclude otherwise who and when began the war, if Andrey Illarionov's findings and documented timeline had been taken into account. Putin admitted in 2012 that Russia had plans for a war with Georgia years before August 2008 and that Russia had trained South Ossetian militias in violation of international law. According to Russian military analyst Pavel Felgenhauer, this admission raised the doubts about the "integrity" of the Tagliavini report.
Stem cells are being studied for several reasons. The molecules and exosomes released from stem cells are also being studied in an effort to make medications. In addition to the functions of the cells themselves, paracrine soluble factors produced by stem cells, known as the stem cell secretome, have been found to be another mechanism by which stem cell-based therapies mediate their effects in degenerative, autoimmune, and inflammatory diseases.
=== Solution === Many growers resorted to their own methods in attempt to resolve the issue. Chemicals and pesticides were used to no avail. In desperation, some growers positioned toads under each vine, and others allowed their poultry to roam free in the hope they would eat the insects. None of these methods were successful. After Charles Valentine Riley, Missouri's state entomologist, confirmed Planchon's theory, Leo Laliman and Gaston Bazille, two French wine growers, both suggested the possibility that if vinifera vines could be combined, by means of grafting, with the aphid-resistant American vines, then the problem might be solved. Thomas Volney Munson was consulted and provided native Texan rootstocks for grafting. Because of Munson's role, the French government in 1888 sent a delegation to Denison, Texas, to confer on him the French Legion of Honor Chevalier du Mérite Agricole. Another viticulturist, Hermann Jaeger of Neosho, Missouri, was pivotal in the rescue of the French vineyards, as well. Jaeger working with the Missouri state entomologist George Hussman, had already raised vines with resistance to the pest. Indeed, several of the rootstalk varietals T.V. Munson had developed in Texas (Mrs Munson, Muench, and Neva Munson) were grafts with the hardy Neosho hybrids Jaeger had developed in Missouri. Jaeger exported 17 boxcars of his resistant rootstock to France.
Sources: en.wikipedia.org
=== Ubiquitination and role in development === Cereblon forms an E3 ubiquitin ligase complex with damaged DNA binding protein 1 (DDB1), cullin-4A (CUL4A), and regulator of cullins 1 (ROC1). This complex ubiquitinates a number of other proteins and marks them for degradation via the proteasome. Through a mechanism which has not been completely elucidated, this ubiquitination results in reduced levels of fibroblast growth factor 8 (FGF8) and fibroblast growth factor 10 (FGF10). FGF8 in turn regulates a number of developmental processes, such as limb and auditory vesicle formation. The net result is that this ubiquitin ligase complex is important for limb outgrowth in embryos. At the molecular level, C-terminal cyclic imides have been identified as endogenous degrons recognized by cereblon. Cyclic imides can arise through spontaneous peptide-bond cleavage at asparagine or glutamine residues in aging proteins, and have long been observed in proteins such as α-crystallin. In 2022, C-terminal aspartimide and aminoglutarimide residues were shown to bind the thalidomide-binding domain of cereblon and to function as degrons promoting CRBN-dependent ubiquitination and proteasomal degradation. In the absence of cereblon, DDB1 forms a complex with DDB2 that functions as a DNA damage-binding protein. Furthermore, cereblon and DDB2 bind to DDB1 in a competitive manner.
==== Cyanohydrins and cyanogenic glycosides ==== Cyanohydrins and their glycosides, referred to as cyanogenic glycosides, are widespread in nature and occur in several thousand plant species. More than one hundred naturally occurring cyanogenic glycosides have been identified. Plants utilize cyanogenic glycosides for defense and possibly also as a nitrogen storage buffer. They are biosynthesized from a limited number of amino acids and various carbohydrates. Upon tissue damage, the glycosides come into contact with enzymes (Β-glucosidase and hydroxynitrillyase), which first release the aglycone (a cyanohydrin) and subsequently cleave it into a carbonyl compound and toxic hydrocyanic acid. Amygdalin is a glycoside of mandelonitrile and one of the most widespread cyanogenic glycosides; it occurs particularly in the seeds of the rose family (Rosaceae), including cultivated apple, apricot, peach, plum, cherry, and almond tree. Whereas amygdalin is confined to the seeds of peaches, other parts of the plant predominantly contain prunasin. Prunasin is likewise a glycoside of mandelonitrile; however, its sugar moiety is a monosaccharide (rather than a disaccharide as in amygdalin). In almonds and bitter almonds, prunasin serves as a biosynthetic precursor of amygdalin. Prunasin is also present in laurel cherry. Prunasin and sambunigrin, along with several other cyanogenic glycosides, occur in passion flower; in papaya, prunasin predominates.
Mauritius is just one example of an island state which is used as a stopover by drug smugglers intending to continue their journey onwards, often to the coast of Africa. This has been particularly problematic for Mauritius, as it has had numerous social effects for the population. Facilitators in Mauritius, and other trans-shipment states, are often paid with product which means they sell it to locals. Therefore, consumer markets develop locally, thus increasing demand and drug-dependency. Drug abuse is a significant problem within Mauritius, which is regularly evidenced by the ‘World Drug Report’. In 2008, the report illustrated that 2% of the population of Mauritius were affected by the use of opioids, such as heroin. A significant proportion of these drugs enter the country through the coastline, which has been linked to a lack of surveillance in these places and the surrounding maritime areas. Many of the illicit substances enter on private yachts, which are not regularly checked. In 2012, a steward previously involved in drug trafficking, expressed that the conditions of the maritime environment made smuggling simple as the oceans are so vast and avoiding capture is easy. A 1986 report from the CIA expressed concern over the entry of illegal drugs to Mauritius, stating that these were both consumed locally and smuggled onwards to South Africa. Therefore, this has been a long-standing problem, which has become entrenched in Mauritian society. These drugs largely originate from Pakistan, India and South Africa, and are smuggled through the Indian Ocean.
Sources: en.wikipedia.org
Most published work uses intranasal application, either as drops or as a nasal spray. Injection routes appear in a smaller set of animal experiments. Oral use is uncommon in the literature because peptide breakdown and poor absorption limit this route.
Reported human trials are few, brief and originate mainly from one country. They describe effects on anxiety-related measures, but sample sizes are small and reporting is limited. The results are widely regarded as preliminary rather than confirmed.
Reverse-phase liquid chromatography is used to assess purity and separation of related impurities. Mass spectrometry confirms that the observed molecular mass matches the expected peptide. A certificate of analysis from the supplier is the usual document of record.
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.