nasal formulation is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Updated 2025-12-11. Numbers and descriptions here follow the published literature rather than marketing material.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Its chain combines the first seven residues of corticotropin with a C-terminal proline-glycine-proline extension, a modification intended to slow enzymatic breakdown. The free peptide has a molecular mass near 813.9 daltons. It belongs to the class of ACTH-derived fragments studied for central nervous system activity rather than for adrenal steroid stimulation. This structural relationship to a natural hormone fragment is the usual starting point for describing the compound in the literature.
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.
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.
Lyophilized material is chemically stable for extended periods when kept dry, cold, and protected from light. The powder is hygroscopic, so vials should be warmed to room temperature before opening to reduce condensation on the contents. Once dissolved, the peptide is far less stable because peptide bonds are susceptible to hydrolysis and the methionine residue can oxidize. Solutions are typically aliquoted and held at 2-8 °C for short intervals or frozen for longer ones, and repeated freeze-thaw cycles should be avoided.
| 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 |
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。
Semax 是一种人工合成的七肽,氨基酸序列为 Met-Glu-His-Phe-Pro-Gly-Pro,单字母缩写记作 MEHFPGP。它被归类为促肾上腺皮质激素片段 ACTH(4-10) 的结构类似物,但并不天然存在于生物体内。母体片段 ACTH(4-10) 的序列为 Met-Glu-His-Phe-Arg-Trp-Gly,Semax 替换了中间两个残基,并在羧基端延长了 Pro-Gly-Pro 三肽。这种延长被普遍认为能提升分子对肽酶的耐受性。
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.
Scientific literature on semax is unevenly distributed. A substantial share of published work originates from a small number of laboratories in Russia, while independent replication elsewhere is limited. Human data consist mostly of small trials with short follow-up, and several reported outcomes rely on subjective rating scales. Questions about how much intact peptide reaches the central nervous system after nasal administration, and how long it persists there, are still unresolved. The compound is best described as an active research subject rather than a settled pharmacological agent.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It was derived from the ACTH(4-10) fragment, a short segment of adrenocorticotropic hormone that lacks the hormonal activity associated with the full-length peptide. Researchers at the Institute of Molecular Genetics in Moscow developed the compound during the 1980s. It has been registered as a pharmaceutical product in Russia and several neighbouring countries, where it is supplied as a nasal solution, and it is also sold internationally as a research chemical.
== History == The chain was founded in Eugene by Ron Fraedrick (1928–2015), who opened the first restaurant near his alma mater, the University of Oregon, at 13th Avenue and High Street in January 1960. In 1962, the first Taco Time franchise opened in White Center, Washington. In the 1970s, the company expanded to 48 restaurants in seven Western states. In 1978, the company franchised its first international restaurant in Lethbridge, Alberta, Canada. In 1979, Taco Time Northwest became a licensee with the rights to franchise and operate the Taco Time concept independently. Taco Time Northwest's operating region includes western Washington from Longview to the Canada–United States border and the eastern Washington cities of Wenatchee and Moses Lake. In 1984, food at a location in The Dalles was allegedly poisoned by members of the Rajneesh movement in a bioterror attack. Taco Time has since expanded, now holding more than 300 franchises in the United States and Canada. They previously had locations in Kuwait, Greece, and Netherlands Antilles (Curaçao) which seem to have closed. In 2003, the company was bought by Kahala Brands of Scottsdale, Arizona.
=== Additives === The most common additive to the Stille reaction is stoichiometric or co-catalytic copper(I), specifically copper iodide, which can enhance rates up by >103 fold. It has been theorized that in polar solvents copper transmetalate with the organostannane. The resulting organocuprate reagent could then transmetalate with the palladium catalyst. Furthermore, in ethereal solvents, the copper could also facilitate the removal of a phosphine ligand, activating the Pd center. Lithium chloride has been found to be a powerful rate accelerant in cases where the X group dissociates from palladium (i.e. the open mechanism). The chloride ion is believed to either displace the X group on the palladium making the catalyst more active for transmetalation or by coordination to the Pd(0) adduct to accelerate the oxidative addition. Also, LiCl salt enhances the polarity of the solvent, making it easier for this normally anionic ligand (–Cl, –Br, –OTf, etc.) to leave. This additive is necessary when a solvent like THF is used; however, utilization of a more polar solvent, such as NMP, can replace the need for this salt additive. However, when the coupling's transmetalation step proceeds via the cyclic mechanism, addition of lithium chloride can actually decrease the rate. As in the cyclic mechanism, a neutral ligand, such as phosphine, must dissociate instead of the anionic X group. Finally, sources of fluoride ions, such as cesium fluoride, also effect on the catalytic cycle.
A third, only marginally related concept was proposed in 1923 by Gilbert N. Lewis, which includes reactions with acid–base characteristics that do not involve a proton transfer. A Lewis acid is a species that accepts a pair of electrons from another species; in other words, it is an electron pair acceptor. Brønsted acid–base reactions are proton transfer reactions while Lewis acid–base reactions are electron pair transfers. Many Lewis acids are not Brønsted–Lowry acids. Contrast how the following reactions are described in terms of acid–base chemistry:
99mTc's half-life of 6.0066 hours is considerably longer (by 14 orders of magnitude, at least) than most nuclear isomers, though not unique. This is still a short half-life relative to many other known modes of radioactive decay and it is in the middle of the range of half-lives for radiopharmaceuticals used for medical imaging. After gamma emission or internal conversion, the resulting ground-state technetium-99 then decays with a half-life of 211,000 years to stable ruthenium-99. This process emits soft beta radiation and no gamma; the radiation for this is comparatively insignificant because of the long half-life ratio and such low residual radioactivity is a desirable feature for radiopharmaceuticals.
Sources: en.wikipedia.org
The plant was ordered to be planted with great religious care at what is now known as the villa surbana, where it grew into a grove. According to Jane Clark Reeder, when Julio-Claudians had military success they would take a laurel branch from the villa.
A functional graphene integrated circuit was demonstrated—a complementary inverter consisting of one p- and one n-type transistor. However, this inverter suffered from low voltage gain. Typically, the amplitude of the output signal is about 40 times less than that of the input signal. Moreover, none of these circuits operated at frequencies higher than 25 kHz. In the same year, tight-binding numerical simulations demonstrated that the band-gap induced in graphene bilayer field effect transistors is not sufficiently large for high-performance transistors for digital applications, but can be sufficient for ultra-low voltage applications, when exploiting a tunnel-FET architecture. In February 2010, researchers announced graphene transistors with an on-off rate of 100 gigahertz, far exceeding prior rates, and exceeding the speed of silicon transistors with an equal gate length. The 240 nm devices were made with conventional silicon-manufacturing equipment. According to a January 2010 report, graphene was epitaxially grown on SiC in a quantity and with quality suitable for mass production of integrated circuits. At high temperatures, the quantum Hall effect could be measured. IBM built 'processors' using 100 GHz transistors on 2-inch (51 mm) graphene sheets. In June 2011, IBM researchers announced the first graphene-based wafer-scale integrated circuit, a broadband radio mixer. The circuit handled frequencies up to 10 GHz. Its performance was unaffected by temperatures up to 127 °C. In November researchers used 3D printing (additive manufacturing) to fabricate devices.
=== Karl Marx === Marx's Critique of Political Economy clearly shaped Adorno's thinking. As described by Jürgen Habermas, Marxist critique is, for Adorno, a "silent orthodoxy, whose categories [are revealed] in Adorno's cultural critique, although their influence is not explicitly named." Marx's influence on Adorno first came by way of György Lukács's History and Class Consciousness (Geschichte und Klassenbewußtsein). From this text, Adorno took the Marxist categories of commodity fetishism and reification. These are closely related to Adorno's concept of trade, which is central to his philosophy, not exclusively restricted to economic theory. Adorno's "exchange society" (Tauschgesellschaft), with its "insatiable and destructive appetite for expansion," is easily decoded as a description of capitalism. Furthermore, the Marxist concept of ideology is central for Adorno. Class theory, which appears less frequently in Adorno's work, also has its origins in Marxist thinking. Adorno made explicit reference to class in two of his texts: the first, the subchapter "Classes and Strata" (Klassen und Schichten), from his Introduction to the Sociology of Music; the second, an unpublished 1942 essay, "Reflections on Class Theory," published postmortem in his Collected Works.
Mushrooms with psychoactive properties have long played a role in various native medicine traditions in cultures all around the world. They have been used as sacrament in rituals aimed at mental and physical healing, and to facilitate visionary states. One such ritual is the velada ceremony. A practitioner of traditional mushroom use is the shaman or curandera (priest-healer). Psilocybin mushrooms, also referred to as psychedelic mushrooms, possess psychedelic properties. Commonly known as "magic mushrooms" or "'shrooms", they are openly available in smart shops in many parts of the world, or on the black market in countries which have outlawed their sale. Psilocybin mushrooms have been reported to facilitate profound and life-changing insights often described as mystical experiences. Recent scientific work has supported these claims, as well as the long-lasting effects of such induced spiritual experiences.
=== Glass Pasteur pipette === The two types of glass that are usually found in the laboratory and in the Pasteur pipette are borosilicate glass and soda–lime glass. Borosilicate glass is a widely used glass for laboratory apparatus, as it can withstand chemicals and temperatures used in most laboratories. Borosilicate glass is also more economical since the glass can be fabricated easily compared to other types. Soda lime glass, although not as chemically resistant as borosilicate glass, is suitable as a material for inexpensive apparatus such as the Pasteur pipette. Traditionally, glass Pasteur pipettes were made by heating lengths of glass tubing over a flame, before drawing them apart to form a long capillary. This capillary was further heated to bisect, producing two pipettes. Before the advent of rubber bulbs (also called teats) to generate a vacuum, liquid was drawn up through mouth suction. Nowadays, mouth-pipetting is either strongly discouraged or forbidden. Glass Pasteur pipettes can also be used for microscale filtration. By plugging the top (the larger aperture) with cotton or glass wool, a solution may pass through the pipette while insoluble sediment is retained. A rubber bulb may be employed to provide additional pressure if gravity is insufficient. Glass pasteur pipettes can be used to make spotters for thin layer chromatography after pulling it over a flame.
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.
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.