If you have been reading about Semax 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 2026-05-03. Where a claim depends on a specific study, the study is described rather than over-claimed.
Development is attributed to researchers at the Institute of Molecular Genetics in Moscow during the early 1980s, building on earlier Soviet work with ACTH fragments. Russian regulatory approval followed for intranasal use, and the compound has remained commercially available there for decades. Most published human data originate from Russian and, later, some Eastern European clinical reports, which are not always accessible in English translation. Outside that region the material is generally handled as a research chemical rather than a licensed medicine.
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.
Terminology around the compound varies by source. It appears in catalogues and papers as Semax, as the heptapeptide ACTH(4-7)-Pro-Gly-Pro, and under various alphanumeric laboratory codes used by individual suppliers. These names refer to the same sequence but may imply different salt forms, purity grades, or counter-ions. Peptide databases usually list the free base mass, while product descriptions sometimes report acetate or trifluoroacetate salts with a different formula weight. Because naming conventions for research peptides are not standardised across vendors, checking the declared sequence and measured mass is more reliable than relying on a trade name alone.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Its design combines the ACTH(4-7) core fragment with a C-terminal Pro-Gly-Pro extension, a modification intended to improve stability and prolong activity. The molecule is hydrophilic, carries no lipid chains or glycosylation, and has a theoretical mass just over 810 daltons in its free form. All seven residues are proteinogenic amino acids, so no non-natural building blocks appear in the backbone. A free N-terminal methionine and C-terminal proline define the unmodified parent peptide.
| 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 |
该化合物于二十世纪八十年代在俄罗斯被开发，相关工作由俄罗斯科学院分子遗传学研究所的研究团队主导。开发目标并非复制 ACTH 的完整激素活性，而是寻找保留其神经作用方向、同时去除促肾上腺皮质激素释放效应的短肽片段。研究记录显示，这一方向促成了多个相关短肽的合成与筛选，而 Semax 是其中被研究最广泛的一个。当地文献常以 Семакс 这一名称指代它。
研究兴趣主要集中在神经营养因子相关的路径上，包括脑源性神经营养因子与神经生长因子的表达变化。部分实验报告称在特定条件下观察到这些因子的水平上升，但具体信号通路和剂量依赖关系仍未完全厘清。多数公开数据来自细胞模型和动物实验，人体对照研究数量有限。因此，该化合物的作用机制在文献中属于活跃讨论，而非已经确立的定论。
However, some studies have found it to have a high variability, poor reproducibility, and low diagnostic sensitivity. It is also sensitive to various factors such as caffeine and medications, and the iontophoresis procedure may cause skin irritation and discomfort. QSART requires highly specialized equipment needing regular calibration, a humidity- and temperature-controlled room, and trained personnel.
Mass spectrometry (MS) is a near universal detection technique that is recognized throughout the world as the gold standard for identification of manycompounds. MS is an analytical technique in which chemical species are ionized and sorted before detection, and the resulting mass spectrum is used to identify the ions' parent molecules. This makes MS, unlike other detection techniques (such as fluorescence), label-free; i.e. there is no need to bind additional ligands or groups to the molecule of interest in order to receive a signal and identify the compound.
== Further reading == Archives National Library of Scotland, correspondence and papers The National Archives Public Record Office (TNA: PRO), reports on Germany, MH79/358 National Archives of Scotland, correspence with Lord Lothian Rowett Research Institute, Aberdeenshire, corresp. and papers relating to Rowett Research Institute Likenesses from the National Portrait Gallery Lida Moser, photograph, 1949, National Portrait Gallery (NPG) [see illus.] B. Schotz, bronze head, 1950, Hunterian Museum and Art Gallery, Glasgow W. Stoneman, bromide print, 1953, NPG Elliott & Fry, photograph, NPG Elliott & Fry, vintage print, 1942, NPG photograph, repro. in Kay, Memoirs FRS Hansard 1803–2005: contributions in Parliament by John Boyd Orr
Serbs = 6,331,527 (67.96%) Albanians = 1,303,032 (13.99%) Yugoslavs = 441,941 (4.75%) Hungarians = 390,468 (4.19%) Muslims = 215,166 (2.31%) Croats = 149,368 (1.60%) Romani = 110,956 (1.19%) Macedonians = 48,986 (0.53%) Slovenes = 12,006 (0.13%)
=== Odor === Many thiols have strong odors resembling that of garlic. The odors of thiols, particularly those of low molecular weight, are often strong and repulsive. The spray of skunks consists mainly of low-molecular-weight thiols and derivatives. These compounds are detectable by the human nose at concentrations of only 10 parts per billion. Human sweat contains (R)/(S)-3-methyl-3-sulfanylhexan-1-ol (3M3SH), detectable at 2 parts per billion and having an onion-like (S enantiomer) and fruity, grapefruit-like odor (R enantiomer). (Methylthio)methanethiol (MeSCH2SH; MTMT) is a strong-smelling volatile thiol, also detectable at parts per billion levels, found in male mouse urine. Lawrence C. Katz and co-workers showed that MTMT functioned as a semiochemical, activating certain mouse olfactory sensory neurons, and attracting female mice. Copper has been shown to be required by a specific mouse olfactory receptor, MOR244-3, which is highly responsive to MTMT as well as to various other thiols and related compounds. A human olfactory receptor, OR2T11, has been identified which, in the presence of copper, is highly responsive to the gas odorants (see below) ethanethiol and t-butyl mercaptan as well as other low molecular weight thiols, including allyl mercaptan found in human garlic breath, and the strong-smelling cyclic sulfide thietane. Thiols are also responsible for a class of wine faults caused by an unintended reaction between sulfur and yeast, as well as the "skunky" odor of beer that has been exposed to ultraviolet light. Not all thiols have unpleasant odors.
Sources: en.wikipedia.org
Diethyl ether, or simply ether (abbreviated as eth. or Et2O) is an organic compound with the chemical formula (CH3CH2)2O, belonging to the ether class. It is a colourless, highly volatile, sweet-smelling (termed "ethereal odour"), and extremely flammable liquid. It is a common solvent and was formerly used as a general anesthetic.
== External links == Observations Support Homochirality Theory. Photonics TechnologyWorld November 1998. Origins of Homochirality Archived 2010-08-21 at the Wayback Machine. Conference in Nordita Stockholm, February 2008.
=== Neurotoxicity === In the setting of prolonged use, high dosage, and/or kidney dysfunction, hydromorphone has been associated with neuroexcitatory symptoms such as tremor, myoclonus, agitation, and cognitive dysfunction. This toxicity is less than that associated with other classes of opioids such as the pethidine class of synthetics in particular.
== History == Ripasudil (in the form of ripasudil hydrochloride hydrate) was approved by the PMDA of Japan on September 26, 2014. Glanatec, the trade name of the approved formulation, takes the form of an eye drop solution of 0.4% ripasudil, equivalent to 4 g of ripasudil per 1000 mL of solution. The solution is developed, marketed, and distributed by Kowa Pharmaceuticals, but the compound itself was discovered by D. Western Therapeutics Institute, a company who specializes in protein kinase inhibitory compounds. In September 2002, Kowa Company entered a licensing agreement with D. Western Therapeutics Institute, Inc. with regard to global rights of ripasudil. Under this agreement, D. Western Therapeutics Institute is eligible to receive milestone payments from Kowa. Kowa Company was issued a US patent (No. 8,193,193, entitled ‘‘Agent for prevention or treatment of glaucoma’’) on June 5, 2012 for the use of ripasudil in patients with glaucoma. As of June 25th, 2013, Glanatec is a registered U.S. federal trademark attributed to Kowa.
Sources: en.wikipedia.org
=== Processing === Water is removed from the sample in successive stages by the use of increasing concentrations of alcohol. Xylene is used in the last dehydration phase instead of alcohol - this is because the wax used in the next stage is soluble in xylene where it is not in alcohol allowing wax to permeate (infiltrate) the specimen. This process is generally automated and done overnight. The wax infiltrated specimen is then transferred to an individual specimen embedding (usually metal) container. Finally, molten wax is introduced around the specimen in the container and cooled to solidification so as to embed it in the wax block. This process is needed to provide a properly oriented sample sturdy enough for obtaining a thin microtome section(s) for the slide. Once the wax embedded block is finished, sections will be cut from it and usually placed to float on a water bath surface which spreads the section out. This is usually done by hand and is a skilled job (histotechnologist) with the lab personnel making choices about which parts of the specimen microtome wax ribbon to place on slides. A number of slides will usually be prepared from different levels throughout the block. After this the thin section mounted slide is stained and a protective cover slip is mounted on it. For common stains, an automatic process is normally used; but rarely used stains are often done by hand.
== Construction == Incandescent light bulbs consist of an air-tight glass enclosure (the envelope, or bulb) with a filament of tungsten wire inside the bulb, through which an electric current is passed. Contact wires and a base with two (or more) conductors provide electrical connections to the filament. Incandescent light bulbs usually contain a stem or glass mount anchored to the bulb's base that allows the electrical contacts to run through the envelope without air or gas leaks. Small wires embedded in the stem in turn support the filament and its lead wires. An electric current heats the filament to typically 2,000 to 3,300 K (1,730 to 3,030 °C; 3,140 to 5,480 °F), well below tungsten's melting point of 3,695 K (3,422 °C; 6,191 °F). Filament temperatures depend on the filament type, shape, size, and amount of current drawn. The heated filament emits light that approximates a continuous spectrum. The useful part of the emitted energy is visible light, but most energy is given off as heat in the near-infrared wavelengths.
CH3C(O)CO2− + HCO3− + ATP → −O2CCH2C(O)CO2− + ADP + Pi Occurring in the mesophyll of plants, this process proceeds via phosphoenolpyruvate, catalysed by phosphoenolpyruvate carboxylase. Oxaloacetate can also arise from trans- or de- amination of aspartic acid.
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.
It is a synthetic seven-amino-acid peptide built from the ACTH(4-7) sequence plus a Pro-Gly-Pro tail. It belongs to the family of short ACTH fragments studied for nervous-system effects. Its backbone contains only standard amino acids.