This is a working overview of Semax, written for readers who want more than a one-paragraph summary but less than a textbook.
Reviewed 2026-04-02. Anything still debated is marked as such rather than presented as settled.
Development took place during the 1980s at institutes of the Russian Academy of Sciences, where peptide fragments of ACTH were screened for cognitive and neuroprotective effects. The compound received regulatory approval in Russia as a nasal preparation, marketed for conditions such as ischemic stroke, transient ischemic attacks, and optic nerve disorders. Registration in other countries has not followed. Most published clinical reports originate from a small number of Russian research groups, and independent replication outside that setting remains limited. The regulatory status therefore differs sharply between Russia and the rest of the world.
Laboratory work points toward modulation of neurotrophic signaling, particularly expression of brain-derived neurotrophic factor and nerve growth factor in hippocampal tissue. Studies also describe effects on monoamine turnover, inflammatory mediators, and oxidative markers. These observations come mainly from animal models and cultured cells, so the causal chain in humans is not firmly established. Whether the reported molecular changes translate into measurable clinical benefit is an open question. Reviews generally present the mechanism as plausible rather than demonstrated.
Identity and purity are confirmed with reversed-phase high-performance liquid chromatography, typically monitored at 214 nanometres where the peptide bond absorbs. Mass spectrometry, either electrospray or MALDI-TOF, verifies molecular mass against the theoretical value and detects truncation or adduct formation. Amino acid analysis and peptide mapping provide additional confirmation when required. The most frequently reported impurities are deletion sequences from incomplete coupling, methionine sulfoxide from oxidation, and dimeric species formed through non-covalent aggregation. Impurity profiles depend strongly on the synthesis and purification route chosen by the producer.
Published research has focused mainly on neurological and cognitive endpoints in animal models, with proposed mechanisms involving brain-derived neurotrophic factor and related signalling pathways. A substantial share of the human data originates from a limited number of research groups, and independent replication in other countries remains sparse. Regulatory status reflects that distribution: the peptide is registered as a medicine in Russia and appears in some neighbouring markets, while elsewhere it is handled as a research chemical without approved therapeutic labelling. Questions about dose-response relationships, long-term effects, and comparability across studies are still open.
| Property | Value | Notes |
|---|---|---|
| Sequence | Met-Glu-His-Phe-Pro-Gly-Pro | Heptapeptide; ACTH(4-10) analog extended at C-terminus |
| Molecular mass | ~813.9 Da | Free peptide, unmodified |
| Appearance | White to off-white powder | Typical lyophilized solid |
| Solubility | Soluble in water and saline | Also soluble in common aqueous buffers |
| Storage (solid) | -20 °C, desiccated | Protect from moisture and repeated thawing |
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.
稳定性主要由水解与氧化两条路径支配。肽键在中性或弱酸性条件下相对稳定,遇到强碱或长时间高温则明显断裂;甲硫氨酸侧链容易被氧化成亚砜,使主峰前移并拉低实际含量。金属离子、光照和反复冻融会进一步促进降解或聚集。冻干粉在低温避光条件下可存放较长时间,配制后的水溶液通常需要冷藏并尽快用完。
纯度评估以反相高效液相色谱为主,通过主峰面积百分比给出粗略结果,再配合电喷雾质谱核对分子量。氨基酸分析可验证组成比例,手性色谱或毛细管电泳用于检查残基构型。常见杂质包括缺失序列的短肽、氧化产物与二聚体。由于多数市售品不附带完整检验报告,独立第三方检测常被用来核实标称值。
Its frankly grandiose style is transporting in its way, as is the story itself, even in this watered-down form." She also complimented the African scenery, noting that "Cry Freedom can also be admired for Ronnie Taylor's picturesque cinematography". The Variety Staff felt Washington did "a remarkable job of transforming himself into the articulte [sic] and mesmerizing black nationalist leader, whose refusal to keep silent led to his death in police custody and a subsequent coverup." On Kline's performance, they noticed how his "low-key screen presence serves him well in his portrayal of the strong-willed but even-tempered journalist." Film critic Gene Siskel of the Chicago Tribune gave the film a thumbs up review calling it "fresh" and a "solid adventure" while commenting "its images do remain in the mind ... I admire this film very much." He thought both Washington's and Kline's portrayals were "effective" and "quite good". Similarly, Michael Price writing in the Fort Worth Press viewed Cry Freedom as often "harrowing and naturalistic but ultimately self-important in its indictment of police-state politics."
Microorganisms have a much higher growth rate (algae: 2–6 hours, yeast: 1–3 hours, bacteria: 0.5–2 hours). This also allows selection for strains with high yield and good nutritional composition more quickly and easily compared to breeding. Whereas large parts of crops, such as stems, leaves and roots, are not edible, single-cell microorganisms can be used entirely. Whereas parts of the edible fraction of crops are indigestible, many microorganisms are digestible at a much higher fraction. Microorganisms usually have a much higher protein content of 30–70% in the dry mass than vegetables or grains. The amino acid profiles of many SCP microorganisms often have excellent nutritional quality, comparable to hen's eggs. Some microorganisms can build vitamins and nutrients which eukaryotic organisms such as plants cannot produce or not produce in significant amounts, including vitamin B12. Microorganisms can utilize a broad spectrum of raw materials as carbon sources including alkanes, methanol, methane, ethanol and sugars. What was considered "waste product" often can be reclaimed as nutrients and support growth of edible microorganisms. Like plants, autotrophic microorganisms are capable of growing on CO2. Some of them, such as bacteria with the Wood–Ljungdahl pathway or the reductive TCA can fix CO2 with efficiencies ranging from 2-3 times to 10 times more efficiently than plants, when also considering the effects of photoinhibition. Some bacteria, such as several homoacetogenic clostridia, are capable of performing syngas fermentation.
== Commercial performance == The album debuted at No. 145 on Billboard 200, and No. 5 on Top Dance/Electronic Albums for charts dated November 24, 2012, selling 4,000 copies in the first week. The album reached No. 77 on Billboard 200 the following week, and No. 2 on Dance/Electronic Albums. The album has sold 52,000 copies in the United States as of August 2016.
After the war, part of the Great Chain was saved for posterity and the rest relegated to the West Point Foundry furnaces near Cold Spring, New York, to be melted down. A saved portion was first displayed at the West Point ordnance compound, along with a captured mortar, as shown in a 1905 drawing. Thirteen links are displayed at Trophy Point, one for each of the Thirteen Colonies. Also included are a swivel and clevis. The exhibit is maintained and preserved by the West Point Museum. A section of boom recovered from the river in 1855 is displayed at Washington's Headquarters State Historic Site in Newburgh, New York. Two links of the original chain are also at Raynham Hall in Oyster Bay, New York, the home of Robert Townsend, a cousin of iron works owner Peter Townsend, and (as "Culper Jr") a member of George Washington’s Culper spy ring. Bilking the gullible, John C. Abbey, and later Pollepel Island owner Francis Bannerman, sold counterfeit chain links to collectors and museums.
Sources: en.wikipedia.org
Evidence of early interest in snake venom was prevalent throughout the early 20th century with one of the first big breakthroughs being in the mid-1960s. For example, Halbert Raudonat was one of the first researchers to fractionate Cobra (Naja nivea) venom using a sophisticated dialysis and paper chromatography techniques. Furthermore, Evert Karlsson and David Eaker were able to successfully purify the specific neurotoxins found in Cobra (Naja nigricollis) venom and found that those isolated polypeptides had a consistent molecular weight of around 7000. Future research in this field would eventually lead to indirect predictive models and then direct crystal structures of important many protein superfamilies. For example, Barbara Low was one of the first to release a 3D structure of the three-finger protein (TFP), Erabutoxin-b. TFPs are an example of α-Neurotoxins, they are small in structure (~60-80 amino acid length) and are a predominant component found in many snake venoms (representing up to 70%-95% of all toxins).
The Union for the Defense of the Motherland and Freedom (Russian: Союз защиты Родины и Свободы) was an underground anti-Bolshevik organization active during the early stages of the Russian Civil War. It was formally established in March 1918 under the leadership of Boris Savinkov, although the idea for the organization had emerged in late 1917. Its creation was supported by elements of the Volunteer Army, including Generals Lavr Kornilov and Mikhail Alekseev. The organization sought to coordinate anti-Bolshevik resistance and prepare armed uprisings in central Russia. It is best known for its role in organizing the Yaroslavl Uprising, the Rybinsk Uprising, the Murom Uprising, and the Elatma Uprising in 1918. Although it established branches in several Russian cities, it was largely destroyed following the suppression of these revolts. A successor organization, the People's Union for the Defense of the Motherland and Freedom, was reconstituted in exile in 1921 and continued anti-Bolshevik underground activity until it was dismantled by the Soviet secret police in 1924. Savinkov himself was arrested in 1924 and died in OGPU custody in 1925.
The Russian Partition (Polish: zabór rosyjski) constituted the former territories of the Polish–Lithuanian Commonwealth that were annexed by the Russian Empire in the course of late-18th-century Partitions of Poland. The Russian acquisition encompassed the largest share of the Polish–Lithuanian Commonwealth's population, living on 463,200 km2 (178,800 sq mi) of land constituting the eastern and central territory of the former Commonwealth. The three partitions, which took place in 1772, 1793 and 1795, resulted in the complete loss of Poland's and Lithuania's sovereignty, with their territories split between Russia, Prussia and Austria. The majority of Lithuania's former territory was annexed by the Russian Empire, except for Užnemunė (a geographical area on the left bank of the River Neman) which was annexed by Prussia. The Napoleonic Wars saw significant parts of Prussia's and Austria's partitions reconstituted as the Duchy of Warsaw (a French client state in a personal union under Saxony), most of which was then reconstituted as the Kingdom of Poland within the Russian Empire in 1815.
Thionyl chloride is an inorganic compound with the chemical formula SOCl2. It is a moderately volatile, colourless liquid with an unpleasant acrid odour. Thionyl chloride is primarily used as a chlorinating reagent, with approximately 45,000 tonnes (50,000 short tons) per year being produced during the early 1990s, but is occasionally also used as a solvent. It is toxic, reacts with water, and is also listed under the Chemical Weapons Convention as it may be used for the production of chemical weapons. Thionyl chloride is sometimes confused with sulfuryl chloride, SO2Cl2, but the properties of these compounds differ significantly. Sulfuryl chloride is a source of chlorine whereas thionyl chloride is a source of chloride ions.
Cocaine has a short elimination half-life of 0.7–1.5 hours and is extensively metabolized by plasma esterases and also by liver cholinesterases, with only about 1% excreted unchanged in the urine. The metabolism is dominated by hydrolytic ester cleavage, so the eliminated metabolites consist mostly of benzoylecgonine (BE), the major metabolite, and other metabolites in lesser amounts such as ecgonine methyl ester (EME) and ecgonine. Further minor metabolites of cocaine include norcocaine, p-hydroxycocaine, m-hydroxycocaine, p-hydroxybenzoylecgonine (pOHBE), and m-hydroxybenzoylecgonine. Depending on liver and kidney functions, cocaine metabolites are detectable in urine between three and eight days. Generally speaking benzoylecgonine is eliminated from someone's urine between three and five days. In urine from heavy cocaine users, benzoylecgonine can be detected within four hours after intake and in concentrations greater than 150 ng/mL for up to eight days later.
Sources: en.wikipedia.org
Magnetic nanoparticles (MNPs) are a class of nanoparticle that can be manipulated using magnetic fields. Such particles commonly consist of two components, a magnetic material, often iron, nickel and cobalt, and a chemical component that has functionality. While nanoparticles are smaller than 1 micrometer in diameter (typically 1–100 nanometers), the larger microbeads are 0.5–500 micrometer in diameter. Magnetic nanoparticle clusters that are composed of a number of individual magnetic nanoparticles are known as magnetic nanobeads with a diameter of 50–200 nanometers. Magnetic nanoparticle clusters are a basis for their further magnetic assembly into magnetic nanochains. The magnetic nanoparticles have been the focus of much research recently because they possess attractive properties which could see potential use in catalysis including nanomaterial-based catalysts, biomedicine and tissue specific targeting, magnetically tunable colloidal photonic crystals, microfluidics, magnetic resonance imaging, magnetic particle imaging, data storage, environmental remediation, nanofluids, optical filters, defect sensor, magnetic cooling and cation sensors.
=== Analogs === Some analog substances have been created which mimic caffeine's properties with either function or structure or both. Of the latter group are the xanthines DMPX and 8-chlorotheophylline, which is an ingredient in dramamine. Members of a class of nitrogen substituted xanthines are often proposed as potential alternatives to caffeine. Many other xanthine analogues constituting the adenosine receptor antagonist class have also been elucidated. Some other caffeine analogs:
Peripherally, mineralization can be seen to be incomplete, whereas centrally the mineralizing front shows ongoing mineralizing. The innermost layer of dentin is known as predentin, and is the initial dentin matrix that is laid down prior to mineralization. It can be distinguished by its pale color when stained with haematoxylin and eosin. The presence of odontoblastic processes here allows the secretion of matrix components. Predentin can be 10-40μm in width, depending on its rate of deposition.
Israelite presence in Canaan was also established before Joshua's conquests according to a few biblical traditions. The history of the Israelite people can be divided into these categories, according to the Hebrew Bible:
Sources: en.wikipedia.org
Semax is a synthetic seven-amino-acid peptide derived from a fragment of corticotropin. It is used in Russia as a nasal preparation, while elsewhere it is studied as a research compound. It is not approved as a medicine in most countries.
Its sequence corresponds to the 4-10 region of corticotropin extended by three residues. This fragment lacks the region responsible for adrenal steroid release, so it is explored for neural rather than hormonal effects. The relationship explains the compound's classification among ACTH-derived peptides.
It holds approval in Russia for several neurological indications as a nasal spray or drop formulation. Regulatory agencies in the United States and the European Union have not approved it. Products sold elsewhere are generally labeled for research use only.
Reversed-phase HPLC gives the main purity figure, most often with UV detection near 214 nanometres. Mass spectrometry then confirms the molecular mass. Together the two methods distinguish a correct sequence from a closely related impurity.