intranasal delivery comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Updated 2025-12-24. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide | Tuftsin analogue with a C-terminal Pro-Gly-Pro tail |
| Amino acid sequence | Thr-Lys-Pro-Arg-Pro-Gly-Pro | Abbreviated TKPRPGP in most catalogues |
| Molecular mass | About 752 Da | Value for the free peptide |
| Solubility | Freely soluble in water | Aqueous solutions are kept cold and used promptly |
| Typical storage | -20 °C, dry, protected from light | Applies to the lyophilised powder before reconstitution |
Reverse-phase high-performance liquid chromatography with ultraviolet detection near 214 nanometres is the standard purity method. Mass spectrometry, typically electrospray ionisation, confirms identity through the expected mass-to-charge pattern. Amino acid analysis can verify composition independently. Chiral purity requires separate techniques such as derivatisation followed by chromatographic separation, and such data are rarely reported for research-grade material.
Quantification in biological matrices relies on liquid chromatography coupled to tandem mass spectrometry with stable-isotope internal standards. Low plasma concentrations and adsorption to container surfaces both complicate measurement. Solid-phase extraction is often needed to reduce matrix interference before injection. Reported limits of quantification differ widely between laboratories, which makes direct comparison of pharmacokinetic results difficult and limits meta-analysis.
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.
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.
Eukaryotic translation termination factor 1 (eRF1), also referred to as TB3-1 or SUP45L1, is a protein that is encoded by the ERF1 gene. In Eukaryotes, eRF1 is an essential protein involved in stop codon recognition in translation, termination of translation, and nonsense mediated mRNA decay via the SURF complex.
Throughout history, a variety of poisons have been used to commit murder, including arsenic, nightshade, hemlock, strychnine, and curare. Until the early 19th century, there were no methods to accurately determine if a particular chemical was present, and poisoners were rarely punished for their crimes. In 1836, one of the first major contributions to forensic chemistry was introduced by British chemist James Marsh. He created the Marsh test for arsenic detection, which was subsequently used successfully in a murder trial. It was also during this time that forensic toxicology began to be recognized as a distinct field. Mathieu Orfila, the "father of toxicology", made great advancements to the field during the early 19th century. A pioneer in the development of forensic microscopy, Orfila contributed to the advancement of this method for the detection of blood and semen. Orfila was also the first chemist to successfully classify different chemicals into categories such as corrosives, narcotics, and astringents. The next advancement in the detection of poisons came in 1850 when a valid method for detecting vegetable alkaloids in human tissue was created by chemist Jean Stas. Stas's method was quickly adopted and used successfully in court to convict Count Hippolyte Visart de Bocarmé of murdering his brother-in-law by nicotine poisoning. Stas was able to successfully isolate the alkaloid from the organs of the victim. Stas's protocol was subsequently altered to incorporate tests for caffeine, quinine, morphine, strychnine, atropine, and opium.
== History == The band was launched by vocalist Thomas Anselmi and guitarist Christian Thorvaldson, former members of the short-lived and controversial band Slow, with new bassist Eric Marxsen and drummer Pete Bourne. The band was formed in 1987, when Anselmi and Thorvaldson settled on that name after having collaborated under the short-lived band names Mo and Christian Thorvaldson's Freeze-Dried Dog since the demise of Slow. Initially, the band spelled its name as the symbol ©, pronounced as "Circle C". Under that name, they released a self-titled debut album via Geffen Records in 1991. That album sold poorly, and the band was dropped from Geffen. After a few years of struggling to continue in the music industry, they were signed to BMG Music, releasing their second album Love Story in 1996 under the name Copyright. The singles "Transfiguration" and "Radio" were released from that album. Love Story was a shortlisted Juno Award nominee for Best Alternative Album at the Juno Awards of 1998. The album The Hidden World followed in 2001, with the song "Rock Machine" being released as a single. The band disbanded not long after.
On June 23, 2021, the NPR station CapRadio reported that Newsom and Cal Fire had falsely claimed in January 2020 that 90,000 acres (36,000 ha) of land at risk for wildfires had been treated with fuel breaks and prescribed burns; the actual treated area was 11,399 acres (4,613 ha), an overstatement of 690%. According to CapRadio, the fuel breaks of the 35 "priority projects" Newsom had touted, which were meant to ensure the quick evacuation of residents while preventing traffic jams and a repeat of events in the 2018 fire that destroyed the town of Paradise, where at least eight evacuees burned to death in their vehicles, were struggling to mitigate fire spread in almost every instance while failing to prevent evacuation traffic jams. The same day CapRadio revealed the oversight, leaked emails showed that Newsom's handpicked Cal Fire chief had ordered the removal of the original statement. In another report in April 2022, CapRadio found a program, hailed in 2020 by the Newsom administration to fast-track environmental reviews on high-priority fire prevention projects, had failed to make progress. KXTV released a series of reports chronicling PG&E's liabilities after committing 91 felonies in the Santa Rosa and Paradise fires. Newsom was accused of accepting campaign donations from PG&E in order to change the CPUC's ruling on PG&E's safety license. The rating change allowed PG&E to avoid billions of dollars in extra fees.
== External links == lipopolysaccharide-binding+protein at the U.S. National Library of Medicine Medical Subject Headings (MeSH) This article incorporates text from the United States National Library of Medicine, which is in the public domain.
Sources: en.wikipedia.org
Seaborg was notified and the team left to sleep. Additional analysis and further experimentation showed the produced mendelevium isotope to have the expected mass of 256 and decay by electron capture to fermium-256 (half-life 157.6 minutes), the source of the observed fission.
== P == p53 - package - palindromic sequence - palmitoyl acyltransferase - Parkinson's disease - Partial cleavage stimulation factor domain - pBR322 - PCR - pedigree - peptide - peptide-transporting ATPase - peptide bond - phage - phagemid - phenotype - phenylacetaldoxime dehydratase - PhIP-Seq - phosphatase, alkaline - phosphatidylcholine 12-monooxygenase - phosphatidylcholine desaturase - phosphatidylinositol a-mannosyltransferase - phosphodiester bond - phospholipid acyltransferase - phosphonate-transporting ATPase - phosphorylation - physical map - plant calmodulin-binding domain - plasmid - plastoquinol/plastocyanin reductase - point mutation - poly-A track - polyA tail - polyacrylamide gel - polyclonal antibodies - polydactyly - polymerase - polymerase chain reaction - polymorphism - polynucleotide kinase - polypeptide - polyvinyl-alcohol dehydrogenase (acceptor) - positional cloning - positional sequencing - post-transcriptional regulation - post-translational modification - post-translational processing - post-translational regulation - PRE - precursor mRNA - primary immunodeficiency - primary transcript - primer - primer extension - probe - processivity - progesterone 5alpha-reductase - promoter - pronucleus - prostate cancer - protease - proteasome - proteasome ATPase - protein - Protein translocation - proto-oncogene - pseudobaptigenin synthase - pseudogene - pseudoknot - pseudorevertant - pulse sequence database - pulsed field gel electrophoresis - purine - PyrC leader - PyrD leader - pyrimidine
=== Mexican women === Immigration of Mexican citizens into the United States caused much controversy in how well they had adjusted to the American life and culture. Because of this, starting in the early 20th century, they were deemed as a significant problem to the community as they were believed to be mentally weak due to their prolonged adjustment to the American culture. The increase of city populations also led to the belief that mental health degraded, as more mental breakdowns seemed prevalent. This discrimination against Mexican and Mexican-Americans led to eugenics laws in which women were targeted and utilized in sterilization procedures. Starting in the year 1909, women of Mexican descent were used as targets for the eugenics movement to reinforce population control and purity. Women of all ages were victims of the many sterilization acts performed in hospitals, correction facilities, and asylums, but younger women were especially targeted. Pacific Colony (later known as Lanterman Developmental Center), a home designated for the mentally defective in LA, California, took in many young women and classified them as mentally defective and sexually delinquent starting in 1944. According to laws in California justifying sterilization acts, staff at this clinic deemed it was in the best interests of society to go forth with the procedure on some of the women who were sent here. In Los Angeles, between 1969 and 1973, Mexican and Chicana (Mexican-American) women were also disproportionately targeted by involuntary sterilizations.
With superparamagnetic beads, the sample is placed in a magnetic field so that the beads can collect on the side of the tube. This procedure is generally complete in approximately 30 seconds, and the remaining (unwanted) liquid is pipetted away. Washes are accomplished by resuspending the beads (off the magnet) with the washing solution and then concentrating the beads back on the tube wall (by placing the tube back on the magnet). The washing is generally repeated several times to ensure adequate removal of contaminants. If the superparamagnetic beads are homogeneous in size and the magnet has been designed properly, the beads will concentrate uniformly on the side of the tube and the washing solution can be easily and completely removed. After washing, the precipitated protein(s) are eluted and analyzed by gel electrophoresis, mass spectrometry, western blotting, or any number of other methods for identifying constituents in the complex. Protocol times for immunoprecipitation vary greatly due to a variety of factors, with protocol times increasing with the number of washes necessary or with the slower reaction kinetics of porous agarose beads.
=== Women === Hyperandrogenism, especially high levels of testosterone, can cause serious adverse effects if left untreated. High testosterone levels are associated with other health conditions such as obesity, hypertension, amenorrhea (cessation of menstrual cycles), and ovulatory dysfunction, which can lead to infertility. Prominent signs of hyperandrogenism are hirsutism (unwanted growth of hair, especially in the abdominal region and on the back), adult acne, deepening of the voice, and alopecia (balding). Hyperandrogenism has also been observed to increase insulin tolerance, which can lead to type two diabetes and dyslipidemia, such as high cholesterol. These effects may have psychological impacts, sometimes leading to social anxiety and depression, especially in adolescent girls and young women. Paired with obesity and hirsutism, it can cause the individual to have low self-esteem.
Sources: en.wikipedia.org
Selank is a seven-amino-acid peptide built from the tuftsin sequence plus a Pro-Gly-Pro tail. It is produced by chemical synthesis rather than extracted from a natural source. The free peptide is usually supplied as a lyophilised powder or in an aqueous formulation.
Tuftsin is a natural tetrapeptide derived from the Fc portion of immunoglobulin G. Selank retains that tetrapeptide at its N-terminus and adds three residues to improve resistance to enzymatic breakdown. The relationship is structural, and the two molecules are not interchangeable in experimental work.
It holds a product registration in Russia for intranasal use as an anxiolytic. Registrations of that kind are not automatically accepted by regulators elsewhere. In most other countries it is treated as an unapproved substance or a research material.
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.