This is a working overview of Semax, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-01-17 and is reviewed periodically as new material appears.
Semax is a synthetic heptapeptide whose sequence is Met-Glu-His-Phe-Pro-Gly-Pro. The first four residues correspond to the ACTH(4-10) fragment, while the terminal Pro-Gly-Pro extension was added to improve metabolic stability. Its molecular formula is C37H51N9O10S and its monoisotopic mass is approximately 813.9 Da. The compound is classified as a peptide research chemical and as a registered pharmaceutical product in Russia, but it does not hold marketing approval in the European Union or the United States. Naming conventions vary across supplier catalogs.
Development of the compound took place in the Soviet Union during the 1980s, largely through peptide research groups affiliated with the Shemyakin-Ovchinnikov Institute and Moscow State University. Investigators screened fragments of adrenocorticotropic hormone for activity on the central nervous system while attempting to separate cognitive effects from hormonal ones. The shortened sequence was selected because it retained behavioral activity in animal models without stimulating corticosteroid release. Early publications described the molecule as an ACTH(4-10) analog.
Routine characterization relies on reversed-phase high-performance liquid chromatography to establish purity and on mass spectrometry to confirm molecular identity. Electrospray ionization and matrix-assisted laser desorption ionization are both used for mass verification. Amino acid analysis and peptide mapping can detect sequence errors. Common impurities include truncated sequences, methionine sulfoxide formed by oxidation, and deamidated products. Chromatograms are usually recorded near 214 nm, where the peptide backbone absorbs, and purity is reported as the percentage area of the principal peak.
Verification of a supplied batch generally combines a certificate of analysis with independent testing, because certificates are self-reported documents. A typical package includes a chromatographic trace, a mass spectrum, and a stated water or counter-ion content. Batch-to-batch consistency matters more than a single purity figure when results are compared across experiments. No single mandatory standard governs research-grade peptide release, so laboratories are expected to define their own acceptance criteria. Residual trifluoroacetate from purification is a frequently overlooked counter-ion.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Seven-residue peptide |
| Molecular mass | 813.9 Da | Monoisotopic value |
| Appearance | White to off-white powder | Lyophilized form |
| Solubility | Freely soluble in water | Also soluble in saline and polar solvents |
| Storage (dry) | -20 °C or lower | Desiccated, protected from light |
Later generations of the molecule include an N-acetylated form and an amidated form, both marketed online alongside the parent peptide. These variants differ in terminal chemistry and stability, and they are frequently discussed in the same breath even though they have not been compared in controlled trials. Supply outside formal healthcare systems comes largely from laboratories that synthesize peptides to order. Purity and identity of these materials vary widely, and no single body oversees the international trade.
Semax is a synthetic heptapeptide developed in the Soviet Union during the 1980s by researchers at the Institute of Molecular Genetics in Moscow. It was designed as a truncated analog of adrenocorticotropic hormone, retaining only the fragment spanning residues four through ten. Investigators sought a peptide that would preserve the cognitive effects associated with ACTH while eliminating the hormonal stimulation of the adrenal cortex. The compound entered clinical use in Russia during the following decade.
Russian regulatory authorities approved the peptide for nasal administration, and it remains listed in the national pharmacopoeia under several trade names. Documented indications include acute ischemic stroke, transient ischemic attacks, traumatic brain injury, and certain ophthalmological and neurological conditions. Physicians also prescribe it for cognitive complaints in older patients, although the evidence base for that use is thinner. Outside Russia and a few neighboring states, the substance is not an approved medicine and is sold instead as a research chemical.
Published studies are dominated by animal models of stroke, ischemia, and cognitive impairment, with a smaller number of human trials conducted in Russia. Many of the human reports are small, single-center, and published in Russian-language journals, which limits independent scrutiny. Outcome measures vary between studies and often rely on clinician-rated scales rather than objective biomarkers. Systematic reviews have noted the methodological weaknesses and called for larger, preregistered trials before firm conclusions can be drawn.
Claims about enhanced focus, memory, or mood in healthy people rest mostly on anecdotal reports and community discussion rather than on controlled data. It remains unclear whether any cognitive benefit observed in patients recovering from brain injury would extend to uninjured users. Dose-response relationships, long-term safety, and interactions with other drugs are not well characterized in the peer-reviewed literature. Questions about optimal route of administration and treatment duration likewise remain open.
==== In midlife ==== The midlife crisis may mark the first reliable drop in happiness during an average human's life. Evidence suggests most people generally become happier with age, with the exception of the years 40 – 50, which is the typical age at which a crisis might occur. Researchers specify that people in both their 20s and 70s are happier than during midlife, although the extent of happiness changes at different rates. For example, feelings of stress and anger tend to decline after age 20, worrying drops after age 50, and enjoyment very slowly declines in adulthood but finally starts to rise after age 50. Well-being in late life is more likely to be related to other contextual factors including proximity to death. However, most of this terminal decline in well-being could be attributed to other changes in age-normative functional declines including physical health and function. Also, there is growing debate that assumptions that a single population estimate of age-related changes in well-being truly reflects the lived experiences of older adults has been questioned. The use of growth mixture modelling frameworks has allowed researchers to identify homogenous groups of individuals who are more similar to each other than the population based on their level and change in well-being and has shown that most report stable well-being in their late life and in the decade prior to death.
== Applications of SSMS == Spark source mass spectrometry has been used for trace analysis and multielement analysis applications for highly conducting, semiconducting, and nonconducting materials. Some examples of SSMS applications are the trace element analysis of high-purity materials, multielement analysis of elements in technical alloys, geochemical and cosmochemical samples, biological samples, industrial stream samples, and radioactive material.
=== Retail editions === Half-Life 2 was simultaneously released through Steam, CD, and on DVD in several editions. Customers could order three versions: the" bronze" version includes only Half-Life 2 and Counter-Strike: Source, whereas the "silver" and "gold" editions also include Half-Life: Source and Day of Defeat: Source (ports of the original Half-Life and the Day of Defeat mod to the new engine). The "Gold Edition" additionally includes merchandise, such as a baseball cap, a strategy guide and a CD containing the soundtrack. The boxed retail copies come as standard and collector's editions. The collector's edition includes a T-shirt and sample of the Prima strategy guide. Both the disc and Steam versions require Steam to be installed and active for play to occur. None of the 2004 releases came with an instruction manual, though a reference card was included to guide people through installation and setup. In September 2005, Electronic Arts distributed a "Game of the Year Edition" of Half-Life 2, including Half-Life: Source.
=== Electrospray ionization mass spectrometry === Electrospray ionization mass spectrometry is a very versatile technique, consisting in a transfer of the formed complexes from the injected solution to the gas phase by a soft ionization process without strongly perturbing the complex stability. In addition, a small amount of the prepared solution needs to be injected to obtain the speciation spectra. Speciation of several metal ions can be investigated in monophasic solutions at increasing ligand concentration in order to explore all potential complexes. Collision Induced Dissociation (CID) analysis can be also performed to assess the kinetic stability of the formed complexes by discovering the main fragmentation pathway of the ligand. Besides, the protonation effect on the complexation mechanism can be observed by performing analysis on monophasic solutions at increasing nitric acid concentration. Corroboration of the major complexes involved into the extraction process is generally found by performing experiments on biphasic solutions upon extraction tests. Despite versatility of this spectroscopic technique that directly provides information by changing the ligand to metal ratios, its qualitative nature due to instrumental set-up and potential changes in solution chemistry could partially affect species distribution and its ion abundance. For these reasons, corroboration for the speciation results needs to be found by other spectroscopic techniques.
Sources: en.wikipedia.org
In December 1978, Gaddafi stepped down as Secretary-General of the GPC, announcing his new focus on revolutionary rather than government activities; this was part of his new emphasis on separating the apparatus of the revolution from government. Although no longer in a formal government post, he adopted the title of "Leader of the Revolution" and continued as commander-in-chief of the armed forces. Historian Dirk Vandewalle stated that despite the Jamahariya's claims to being a direct democracy, Libya remained "an exclusionary political system whose decision-making process" was "restricted to a small cadre of advisers and confidantes" surrounding Gaddafi. Libya started constructing a welfare state. In March 1978, the government issued guidelines for housing redistribution, attempting to ensure every adult owned their own home. Most families were banned from owning more than one house, while former rental properties were expropriated by the state and sold to the tenants at a heavily subsidized price. In September, Gaddafi called for the People's Committees to eliminate the "bureaucracy of the public sector" and the "dictatorship of the private sector"; the People's Committees took control of several hundred companies, converting them into worker cooperatives run by elected representatives. In March 1979, the GPC announced the separation of government and revolution, the latter being represented by new Revolutionary Committees, who operated with the People's Committees in schools, universities, unions, the police force, and the military.
==== Viral transduction ==== Viral transduction is a method that uses viral vectors and is used for the stable introduction of genes into the target cells. In this method, the viral vector (virion) infects host cells that by directly transporting DNA into the nucleus of the cell. Two common types of viruses used for transduction are adenoviruses, which tend to be transient, and lentiviruses, which integrate the DNA into the genome. Lentiviral vectors have also been an attractive viral tool because they can transduce in non-dividing cells, allowing for stable transfer in a large range of host cell types.
===== Oceania ===== New Zealand - DMT is classified as a Class A drug under the Misuse of Drugs Act 1975. Australia - DMT is listed as a Schedule 9 prohibited substance in Australia under the Poisons Standard (October 2015). A Schedule 9 drug is outlined in the Poisons Act 1964 as "Substances which may be abused or misused, the manufacture, possession, sale, or use of which should be prohibited by law except when required for medical or scientific research, or for analytical, teaching or training purposes with approval of the CEO". Between 2011 and 2012, the Australian federal government was considering changes to the Australian Criminal Code that would classify any plants containing any amount of DMT as "controlled plants". DMT itself was already controlled under current laws. The proposed changes included other similar blanket bans for other substances, such as a ban on any and all plants containing mescaline or ephedrine. The proposal was not pursued after political embarrassment on realisation that this would make the official floral emblem of Australia, Acacia pycnantha (golden wattle), illegal. The Therapeutic Goods Administration and federal authority had considered a motion to ban the same, but this was withdrawn in May 2012 (as DMT may still hold potential entheogenic value to native and/or religious people). Under the Misuse of Drugs Act 1981 6.0g (3/16oz) of DMT is considered enough to determine a court of trial and 2.0g (1/16oz) is considered intent to sell and supply. In December 2004, the U.S.
== Series overview == Blue Ridge is set in a small Appalachian town in the Blue Ridge Mountains, located in North Carolina. The series follows on from the aftermath of the events of the 2020 film of the same name. A former Green Beret named Jesse Wise has become the town sheriff in order to be closer to his ex‑wife, Ellie and their teenage daughter, Maddie. Although Wise hopes for a quiet life, the community is repeatedly rocked by murders, arson, kidnappings, drug trafficking, and other violent crimes that expose deep‑seated feuds, and long‑buried secrets. The first season aired in spring 2024, and begins with the suspicious fire at the local police station. It shattered Wise's fragile stability as he attempts to juggle family and work life. Investigations into the fire draw him into a series of investigations that pit him against powerful local families and traveling criminals. The series ends with Wise's family in grave danger during a kidknapping at the police station and a tense standoff as attempts are made to rescue the family. Justin Wise's central dilemma deepens in the second season, following the hostage crisis. He took the mountain job for a quieter life and to be closer to Elli and Maddie, but things aren't working out as planned. Instead, both women are actively helping him on the job, with Maddie helping crack a theater murder and Elli joining him in a mountain rescue. While this brings the family closer together, it becomes clear how regularly they are put in danger.
Fellowship of the Australian Academy of Science is made up of about 500 Australian scientists. Scientists judged by their peers to have made an exceptional contribution to knowledge in their field may be elected to Fellowship of the Academy. Fellows are often denoted using the post-nominal FAA (Fellow of the Australian Academy of Science). A small number of distinguished foreign scientists with substantial connections to Australian science are elected as Corresponding Members. Fellows are appointed for life; this table also contains deceased fellows.
Sources: en.wikipedia.org
== Medical use == Silicone gel sheeting is the gold-standard and non-invasive treatment for hypertrophic and keloid scars. During skin injury repair, dermal cells proliferate and migrate from the skin tissue to the wound, producing collagen and causing contraction of the placement dermis. These scars are proliferative due to chronic inflammation and overproduction of abnormal collagen. Common clinical presentations of these scars are raised, thickened, red, or dark-colored. Patients may also experience pain and itching. Hypertrophic scars are elevated scars that remain in the region of the original lesion following mechanical traumas, burns, and necrotizing infections. These scars typically develop in locations under tension, such as shoulders, ankles, knees, and the neck. Hypertrophic scars are generally confined to the boundaries of the original wound and tend to diminish over time.
=== Post-traumatic stress disorder === Two SSRIs are FDA-approved for PTSD: paroxetine and sertraline. The 2023 VA/DoD guideline for PTSD recommends the SSRIs sertraline and paroxetine as first-line pharmacological treatments when trauma-focused therapy is unavailable or not preferred; evidence for other SSRIs is insufficient, and medications are recommended to be tailored to each patient's individual needs. A 2022 Cochrane review found that SSRIs improve PTSD symptoms in 58% of patients compared with 35% on placebo (RR 0.66) and are considered first-line treatment.
Ertapenem, sold under the brand name Invanz, is a carbapenem antibiotic medication used for the treatment of infections of the abdomen, the lungs, the upper part of the female reproductive system, and the diabetic foot. The most common side effects include diarrhoea, nausea, headache, and problems around the area where the medicine is infused. It can significantly reduce the concentrations of valproic acid, an anti-seizure medication, in the blood to the point where it loses its effectiveness. Ertapenem was approved for medical use in the United States in November 2001, and in the European Union in April 2002. It is marketed by Merck.
The ilvGMEDA operon encodes the ilvGM (ALS II) pair as well as a branched-chain-amino-acid transaminase (ilvE), dihydroxy-acid dehydratase (ilvD), and threonine ammonia-lyase (ilvA). It is regulated by feedback inhibition in the form of transcriptional attenuation. That is, transcription is reduced in the presence of the pathway's end-products, the branched-chain amino acids. The ilvBNC operon encodes the ilvBN (ALS I) pair and a ketol-acid reductoisomerase (ilvC). It is similarly regulated, but is specific to isoleucine and leucine; valine does not affect it directly. Both the ilvGMEDA and ilvBNC operons are derepressed during shortages of the branched-chain amino acids by the same mechanism that represses them. Both of these operons as well as the third, ilvIH, are regulated by leucine-responsive protein (Lrp).
Sources: en.wikipedia.org
It is a synthetic peptide of seven amino acids. Its backbone corresponds to a fragment of adrenocorticotropic hormone extended at the carboxyl end. The material is distributed as a lyophilized solid for laboratory use.
The extension was introduced to slow enzymatic breakdown of the peptide in biological systems. Natural ACTH fragments are degraded rapidly by peptidases. Adding the tripeptide was intended to extend the window during which the molecule remains intact.
Most published work consists of animal experiments conducted in a small number of laboratories. Human data are limited in number and size. Whether the observed effects translate into reliable clinical benefit is still unresolved.
Dry powder is normally held at -20 °C or lower, away from light and moisture. Sealed vials can also be kept at 2-8 °C for shorter intervals. Warming to room temperature before opening prevents condensation.