nootropic 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.
Last reviewed on 2026-06-06. Where a claim depends on a specific study, the study is described rather than over-claimed.
Regulatory status differs sharply between jurisdictions. In Russia the peptide is registered as a prescription nasal preparation, while agencies such as the United States Food and Drug Administration have not approved it for any indication. Products sold elsewhere are typically labeled for laboratory research only, and such labels shift responsibility for safe handling to the purchaser. Because the same name covers pharmaceutical-grade nasal drops and bulk research powder, identity and purity documentation becomes the main practical concern when comparing sources.
Semax is a synthetic seven-amino-acid peptide whose sequence extends the ACTH(4-10) fragment with a C-terminal proline-glycine-proline tripeptide. The commonly cited sequence is Met-Glu-His-Phe-Pro-Gly-Pro, giving a molecular formula near C37H51N9O10S and a molecular weight close to 813.9 g/mol. It belongs to the broader class of synthetic ACTH fragments studied for central nervous system effects rather than for adrenal steroid stimulation. In practice the material appears as a lyophilized white powder for laboratory work or as a dilute saline solution in clinical settings.
Regulatory status varies sharply by country. Semax is registered for medical use in Russia, where it appears in formularies as a nasal solution, and it also holds registration in a small number of neighbouring states. It has no approval from the United States Food and Drug Administration or the European Medicines Agency, and it is not a scheduled controlled substance in most jurisdictions. Elsewhere it circulates mainly as laboratory material, so purity documentation comes from suppliers rather than from a national pharmacopoeia.
Semax is a synthetic peptide created in the Soviet Union during the early 1980s by researchers working in Moscow. It was built from the short adrenocorticotropic hormone fragment known as ACTH(4-10), and the chain was then extended with three additional amino acids. The resulting molecule was named semax and entered clinical use in Russia in 1994. It is generally described as a nootropic and neuroprotective agent rather than as a hormone analogue.
The parent fragment ACTH(4-10) carries the sequence Met-Glu-His-Phe-Arg-Trp-Gly. Semax replaces the arginine and tryptophan positions with a proline-glycine-proline tail, giving Met-Glu-His-Phe-Pro-Gly-Pro. That change removes residues associated with adrenal stimulation, so the peptide does not drive cortisol release the way full ACTH does. This distinction shapes how the compound is grouped in the literature, where it sits with neuropeptides and peptide neuromodulators rather than with corticosteroids.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide (ACTH fragment analog) | Not a steroid; does not belong to the melanocortin agonist drugs by marketing category |
| Molecular formula | C37H51N9O10S (commonly cited) | Reported values vary slightly with salt and counter-ion content |
| Appearance | White to off-white lyophilized powder | A single batch may appear as a loose cake or fluffy solid |
| Solubility | Freely soluble in water and aqueous buffer | Stock solutions are usually prepared in sterile water or saline |
| Typical storage | −20 °C or below, desiccated and protected from light | Seal opened vials promptly to limit moisture uptake |
=== Quantitative analysis of mixtures === FD-MS can also be used for quantitative analysis when the method of internal standard is applied. There are two common modes of adding an internal standard: either addition of a homologous compound of known weight to the sample, or addition of an isotopically substituted compound of known weight to it. Many earlier applications of FD to analysis of polar and nonvolatile analytes such as polymers and biological molecules have largely been supplanted by newer ionization techniques. However, FD remains one of the only ionization techniques that can produce simple mass spectra with molecular information from hydrocarbons and other particular analytes. The most commonly encountered application of FD at the present time is the analysis of complex mixtures of hydrocarbons such as that found in petroleum fractions.
=== Ports === Half-Life 2 was released on the Xbox console by Electronic Arts in November 2005. In 2006, Valve partnered with Taito to release Half-Life 2: Survivor, an arcade game, for the Japanese market. Valve re-released Half-Life 2 as part of the 2007 compilation The Orange Box for Windows, Xbox 360 and PlayStation 3. On May 26, 2010, Half-Life 2, Episode One and Episode Two were released for Mac OS X. In 2013, Valve ported Half-Life 2 to Linux and released a free update adding support for the Oculus Rift virtual reality headset. An Nvidia Shield Tablet-exclusive port for Android was released on May 12, 2014.
=== Solvent extraction and complexation chemistry === The liquid-liquid extraction for the selective actinide partitioning (SANEX-like processes) consists of an organic phase, containing an extracting agent dissolved in a suitable solvent mixture, and an aqueous phase, containing the irradiated fuel dissolution in hot nitric acid. The two phases are vigorously mixed to promote the extraction kinetics. The centrifugation process is performed to favour the phase separation and the transfer of the formed complexes from the depleted aqueous phase (raffinate) into the organic phase (extract) where they result more soluble. This solvent separation can be performed by neutral extracting agents dissolved in the solvent. As can be seen in the equation, the solvating ligand (L) extracts the interested metal cation (M) together with its anion (A). The products of this reaction represent all the potential complexes that can form during an extraction process such as
In organisms that use chromosomal crossover to exchange DNA and recombine genes, errors in alignment during meiosis can also cause mutations. Errors in crossover are especially likely when similar sequences cause partner chromosomes to adopt a mistaken alignment; this makes some regions in genomes more prone to mutating in this way. These errors create large structural changes in DNA sequence—duplications, inversions, deletions of entire regions—or the accidental exchange of whole parts of sequences between different chromosomes, chromosomal translocation.
From late May 1900, the first successes of the Boer guerrilla strategy were at Lindley (where 500 Yeomanry surrendered), and at Heilbron (where a large convoy and its escort were captured) and other skirmishes resulting in 1,500 British casualties in less than ten days. In December 1900, De la Rey and Christiaan Beyers attacked and mauled a British brigade at Nooitgedacht, inflicting 650 casualties. As a result, the British, led by Lord Kitchener, mounted extensive searches for Christiaan de Wet, but without success. However, Boer raids on British army camps and other targets were sporadic and poorly planned, and the nature of the Boer guerrilla war itself had no long-term objectives, with the exception to harass the British. This led to a disorganised pattern of scattered engagements between the British and Boers.
Sources: en.wikipedia.org
In the case of germline editing, there is no guarantee that treatment will provide an absolute cure throughout the patient's life and/or whether those genes can be passed onto their offspring. Although CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats), a technique that allows for genes to be edited with ease may present certain benefits, but it may also cause further risks to the human body. For example, there may be technical limitations to CRISPR editing. Until advancements are made to fully equip scientists with the knowledge to understand all potential benefits and risks associated with CRISPR editing, concerns regarding the safety of its applications remain. The possibility that editing could bring about an incomplete or inaccurate genetic sequence has been reported in several experiments related to both animal and human cell line studies. Since it is almost impossible to predict a favorable outcome with certainty, this technique makes germline editing all the more difficult to promote as a definite cure for anyone suffering from terminal illnesses.
James Wallace Jorgenson is an American academic who previously held the position of William Rand Kenan Jr. Distinguished Professor of Chemistry at UNC-Chapel Hill. He is best known for his work developing capillary zone electrophoresis, and is a member of the American Academy of Arts and Sciences.
Narrated by David Malone, directed by David Hamlin, a joint-production with National Geographic made with ZDF of Germany 12 September Britain's Tornado, an Equinox Special about the 2005 Birmingham tornado 27 December The Year the Earth Went Wild, about the Earth's weather during 2005; Phil Cummins of Geoscience Australia; Bill McGuire of the Benfield Hazard Research Centre at UCL; photographer Geoff Mackley; oceanographer Simon Boxall of the National Oceanography Centre in Southampton; David Vaughan (glaciologist) of the British Antarctic Survey; the 2005 Nias–Simeulue earthquake on 28 March 2005; Kerry Sieh of Caltech; Hurricane Dennis and Hurricane Emily (2005) in Florida; storm chaser Mike Theiss; Typhoon Haitang (2005); the 28 July 2005 Ladypool Road Birmingham tornado; Ewan McCullum of the Met Office; Stuart Robinson of TORRO; structural engineer Tim Marshall; the 2005 European floods and Bern; the NOAA Hurricane Hunters on 24 August 2005; Ivor van Heerden of Louisiana State University; the Mississippi River–Gulf Outlet Canal funnelled a storm surge in Louisiana; Waveland, Mississippi on 29 August 2005; Hurricane Rita made landfall in Texas, in late September 2005; Roger Bilham of the Cooperative Institute for Research in Environmental Sciences at University of Colorado Boulder, and the Main Himalayan Thrust earthquake fault. Narrated by Mark Halliley, directed by Simon Ludgate, produced by Chris Hale, made by Pioneer Productions
== Efficacy and side effects == Counterintuitively to the drastic effect of thinly winged insect-venom on neurological processes, some toxins of these hymenopteran insects are used in the field of medicine. An example can be found in tertiapin-Q from the European honey bee (Apis mellifera) which is used in the treatment of pain, multiple sclerosis (MS), and rheumatoid arthritis. The spider wasp is also a hymenopteran insect but its pompilidotoxins are currently not linked to any existing drugs. Therefore there are also no indications for these compounds. PMTXs medical potential has been considered in the past but to no avail. Their possible characteristic to only enhance neuronal activity has already been nullified as early as in 1998 by Harsch et.al who experimentally found that α-PMTX could also disrupt the activity of rat cortical neurons irreversibly and immediately upon administration. The unpredictability of the toxin and the still rather large gap in information on the toxin, contribute to it not having been translated into medicine. However, even though pompilidotoxins are not used as drugs, they do hold a large medical value. This value comes forth from the fact that this neurotoxin of 13 amino acids is so much smaller than its fellow sodium channel-specific polypeptide toxins. For example, pompilidotoxins are much smaller than the conventionally studied sea anemone toxin that has 46 to 49 amino acids, or the α-scorpion toxin of even 60 to 65 residues.
Sources: en.wikipedia.org
It is a short synthetic peptide built from seven amino acids: methionine, glutamic acid, histidine, phenylalanine and three prolines. The sequence derives from the 4-10 fragment of adrenocorticotropic hormone with an added proline-glycine-proline tail. No plant or animal extract is involved; the material is produced by solid-phase peptide synthesis.
It was developed in the Soviet Union during the early 1980s by groups at the Institute of Molecular Genetics in Moscow. Russian approval for intranasal use followed, and it has been marketed there since. Western laboratories encountered it mainly through translated literature and, later, through online research-chemical trade.
It holds a Russian registration as a prescription nasal product but has no approval from the European Medicines Agency or the United States Food and Drug Administration. Buyers outside Russia usually receive material sold strictly for laboratory research. That distinction matters because research-grade and pharmaceutical-grade products carry different documentation and testing expectations.
Registered medical products are most often 0.1% nasal drops. Research suppliers ship lyophilized powder, usually in milligram quantities, which is dissolved before use. The active peptide is the same in both cases; presentation and excipients differ.