If you have been reading about lyophilized powder 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.
Updated 2026-02-10. 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. It corresponds to the ACTH(4-7) fragment extended at the C-terminus by a Pro-Gly-Pro tripeptide, an addition intended to slow enzymatic breakdown. The molecular formula is C37H51N9O10S and the molecular mass is approximately 814 daltons. In the literature it is often described as an ACTH(4-10) analog, although that label reflects a naming convention as much as a precise structural relationship. The compound was developed in Russia and remains most closely associated with that research tradition.
Laboratory descriptions of the material are consistent across suppliers. It appears as a white to off-white lyophilized powder that dissolves readily in water and in polar organic solvents such as dimethyl sulfoxide. Aqueous solutions are clear and colorless at low concentrations. Because the peptide contains methionine, oxidation at the sulfur atom is a recognized degradation pathway, and handling notes usually call for protected, desiccated storage. Reported purity for research-grade lots is generally above 95 percent as measured by reversed-phase high-performance liquid chromatography.
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。
从分子层面看,Semax 是线性七肽,没有二硫键、糖基或脂链修饰,N 端为游离氨基,C 端为游离羧基。分子含组氨酸与谷氨酸侧链,因此在水和甲醇等极性溶剂中溶解良好,在非极性溶剂中溶解有限。计算分子量约为 814 Da,与其质子化离子的质荷比吻合,可用于质谱确认。
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Contains one methionine sulfur atom |
| Molecular mass | Approximately 814 Da | Consistent with a seven-residue peptide |
| Appearance | White to off-white powder | Typical lyophilized form |
| Solubility | Freely soluble in water | Also soluble in dimethyl sulfoxide |
| Typical storage | -20 °C, desiccated | Limits methionine oxidation |
Published research on this peptide originates mainly from Russian laboratories, and the wider international literature is comparatively thin. Studies have used rodent models of stroke, hypoxia, and memory tasks, with a smaller number of human trials reported. Reported outcomes include changes in attention and memory measures, along with effects on neurotrophic factor expression in some experiments. Small sample sizes, inconsistent dosing protocols, and limited independent replication are widely noted limitations, so the strength of the clinical evidence remains an open question.
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.
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.
Semax binds to melanocortin receptors and is thought to influence neuronal survival and plasticity rather than to act through the adrenal axis. Laboratory work has shown increased expression of brain-derived neurotrophic factor and nerve growth factor in treated tissue. Changes in c-Fos, a marker of neuronal activation, have also been reported. Because the peptide is rapidly degraded by peptidases, its effects are generally attributed to downstream signaling cascades rather than to sustained receptor occupancy.
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.
The compound was developed during the 1980s at the Institute of Molecular Genetics in Moscow as part of research on fragments of adrenocorticotropic hormone. Early work examined short ACTH-derived sequences that retained neurotrophic effects while lacking the endocrine activity of the full hormone. Semax entered clinical use in Russia during the 1990s, where it received registration for several neurological indications. Outside that region it remained primarily a laboratory research material rather than an approved therapeutic. English-language literature on it grew more slowly and frequently cited the original Russian studies.
Purity assessment relies mainly on reversed-phase high-performance liquid chromatography, which separates the target heptapeptide from truncated sequences, deletion analogues, and oxidised forms. Mass spectrometry, usually coupled to liquid chromatography, confirms identity through the expected molecular ion and reveals modifications such as methionine sulfoxide formation. Amino acid analysis can verify composition, and tandem mass spectrometry supports sequence confirmation. Ultraviolet detection near 254 to 280 nanometres is convenient because the phenylalanine and histidine residues absorb in that region. Nuclear magnetic resonance is rarely used for routine release testing.
Common degradation pathways include oxidation of the methionine side chain, hydrolysis of the peptide backbone, and aggregation under unfavourable pH or concentration. Stability studies typically monitor the main peak by chromatography and report total related substances as a percentage. Because no official monograph exists, acceptance criteria vary between laboratories, and reported purity values are not directly comparable across suppliers. Analysts therefore document the method, column, and detection wavelength alongside each result, and open questions remain about how much biological activity the oxidised forms retain.
Solid semax is typically supplied as a lyophilised powder that is hygroscopic and sensitive to moisture, light, and repeated temperature cycling. Long-term storage of the dry peptide is generally recommended at approximately -20 degrees Celsius, while shorter working periods may use refrigeration at 2 to 8 degrees Celsius. Vials should remain tightly closed and desiccated when brought to room temperature, because condensation can damage the material before it is weighed. Dividing a batch into aliquots is preferable to thawing one container repeatedly.
3 January 1919: to avoid anarchy in Greater Poland, the Commission of the NRL decides to take over control of the spontaneous uprising but also decides that the decision should be kept secret. 4 January 1919: The Commission of the NRL decrees a new president of the Province of Poznań, Wojciech Trąmpczyński. German authorities call for boycotting him. 5 January 1919: Czarnków, Jutrosin, Kruszwica, Nakło, Nowy Tomyśl, Miejska Górka, Rawicz, Strzelno and Wolsztyn are captured by the Poles. 6 January 1919 The Poles capture Ławica Airport, Poznań, with all aircraft undamaged. Fighting near Czersk and Kościerzyna in Pomerania. Inowrocław captured. 7 January 1919 The Poles divide captured lands into seven Military Districts (Okręg Wojskowy). The Germans recapture Chodzież and Czarnków. 8 January 1919 The Commission of the NRL takes all civil and military authority without declaring territorial range of that power. It also promotes General Józef Dowbor-Muśnicki to commander-in-chief of the uprising forces. The Poles recapture Chodzież Battle of Chodzież and Czarnków. They also win the Battle of Ślesin and capture Sieraków. 9 January 1919 The NRL officially announces that it takes control over Greater Poland. Beginning of polonisation of administration, most former anti-Polish officials being fired. In powiats, German landrats are subordinated to Polish starostas, which take all their power. Poles lose Nakło. Polish airmen bomb military airfield in Frankfurt (Oder) 10 January 1919: fights on southern front near Kąkolewo, Leszno and Rydzyna. Poles capture Sarnowa.
=== Molecular absorption === Theoretically graphene makes an excellent sensor due to its 2D structure. The fact that its entire volume is exposed to its surrounding environment makes it very efficient to detect adsorbed molecules. However, similar to carbon nanotubes, graphene has no dangling bonds on its surface. Gaseous molecules cannot be readily adsorbed onto graphene surfaces, so intrinsically graphene is insensitive. The sensitivity of graphene chemical gas sensors can be dramatically enhanced by functionalization, for example, coating the film with a thin layer of certain polymers. The thin polymer layer acts like a concentrator that absorbs gaseous molecules. The molecule absorption introduces a local change in electrical resistance of graphene sensors. While this effect occurs in other materials, graphene is superior due to its high electrical conductivity (even when few carriers are present) and low noise, which makes this change in resistance detectable.
== Intellectual influences == Like most theorists of the Frankfurt School, Adorno was influenced by the works of Hegel, Marx, and Freud. Their major theories fascinated many left-wing intellectuals in the first half of the 20th century. Lorenz Jäger speaks critically of Adorno's "Achilles' heel" in his political biography: that Adorno placed "almost unlimited trust in finished teachings, in Marxism, psychoanalysis, and the teachings of the Second Viennese School."
There are various government and trade association regulatory bodies for acupuncture in the United Kingdom, the United States, Saudi Arabia, Australia, New Zealand, Japan, Canada, and in European countries and elsewhere. The World Health Organization recommends that an acupuncturist receive 200 hours of specialized training if they are a physician and 2,500 hours for non-physicians before being licensed or certified; many governments have adopted similar standards. In Hong Kong, the practice of acupuncture is regulated by the Chinese Medicine Council, which was formed in 1999 by the Legislative Council. It includes a licensing exam, registration, and degree courses approved by the board. Canada has acupuncture licensing programs in the provinces of British Columbia, Ontario, Alberta and Quebec; standards set by the Chinese Medicine and Acupuncture Association of Canada are used in provinces without government regulation. Regulation in the US began in the 1970s in California, which was eventually followed by every state but Wyoming and Idaho. Licensing requirements vary greatly from state to state. The needles used in acupuncture are regulated in the US by the Food and Drug Administration. In some states acupuncture is regulated by a board of medical examiners, while in others by the board of licensing, health or education. In Japan, acupuncturists are licensed by the Minister of Health, Labour and Welfare after passing an examination and graduating from a technical school or university.
Sources: en.wikipedia.org
== Further reading == ASTM E 111, "Standard Test Method for Young's Modulus, Tangent Modulus, and Chord Modulus" The ASM Handbook (various volumes) contains Young's Modulus for various materials and information on calculations. Online version (subscription required)
Soviet power, unlike that of Hitlerite Germany, is neither schematic nor adventuristic. It does not work by fixed plans. It does not take unnecessary risks. Impervious to logic of reason, and it is highly sensitive to logic of force. For this reason it can easily withdraw—and usually does when strong resistance is encountered at any point. Kennan's cable was hailed in the State Department as "the appreciation of the situation that had long been needed." Kennan himself attributed the enthusiastic reception to timing: "Six months earlier the message would probably have been received in the State Department with raised eyebrows and lips pursed in disapproval. Six months later, it would probably have sounded redundant." Clark Clifford and George Elsey produced a report elaborating on the Long Telegram and proposing concrete policy recommendations based on its analysis. This report, which recommended "restraining and confining" Soviet influence, was presented to Truman on September 24, 1946.
Yeast is the microorganism that is responsible for fermentation in beer. Yeast metabolises the sugars extracted from grains, which produces alcohol and carbon dioxide, and thereby turns wort into beer. In addition to fermenting the beer, yeast influences the character and flavour. The dominant types of yeast used to make beer are Saccharomyces cerevisiae, known as ale yeast, and Saccharomyces pastorianus, known as lager yeast; Brettanomyces ferments lambics, and Torulaspora delbrueckii ferments Bavarian weissbier. Before the role of yeast in fermentation was understood, fermentation involved wild or airborne yeasts, and a few styles such as lambics still use this method today. Emil Christian Hansen, a Danish biochemist employed by the Carlsberg Laboratory, developed pure yeast cultures which were introduced into the Carlsberg brewery in 1883, and pure yeast strains are now the main fermenting source used worldwide.
South Korean president Lee Jae Myung criticized the campaign via X, stating that it insulted the victims and the residents of Gwangju. Starbucks Korea apologized and its CEO, Son Jeong-Hyun, was fired. Starbucks Korea planned to shutter all its stores in South Korea for half a day on June 22 for its staff to attend a history lesson to increase historical awareness and social sensitivities.
==== Hallucinogenic ==== Several studies have implicated CCK as a cause of visual hallucinations in Parkinson's disease. Mutations in CCK receptors in combination with mutated CCK genes potentiate this association. These studies also uncovered potential racial/ethnic differences in the distribution of mutated CCK genes.
Sources: en.wikipedia.org
=== Endocrine === The drug may cause adrenal insufficiency so the level of the adrenocortical hormones should be monitored while taking it. Oral ketoconazole at a dosage range of 400 to 2,000 mg/day has been found to result in a rate of gynecomastia of 21%.
The human body's immune response to a surgically installed foreign object—breast implant, cardiac pacemaker, orthopedic prosthesis—is to encapsulate it with scar tissue capsules of tightly woven collagen fibers, in order to maintain the integrity of the body by isolating the foreign object, and so tolerate its presence. Capsular contracture—which should be distinguished from normal capsular tissue—occurs when the collagen-fiber capsule thickens and compresses the breast implant; it is a painful complication that might distort either the breast implant, or the breast, or both. Capsular contracture is diagnosed through a visual and physical examiniation according to level of increasing severity based on the Baker Grade scale: Baker Grade I, Baker Grade II, Baker Grade III, and Baker Grade IV.
In the summer of 1793 the sans-culottes, the Parisian enragés especially, accused even the most radical Jacobins of being too tolerant of greed and insufficiently universalist. From this far-left point of view, all Jacobins were at fault because all of them tolerated existing civil life and social structures. The sans-culottes also populated the ranks of paramilitary forces charged with physically enforcing the policies and legislation of the revolutionary government, a task that commonly included violence and the carrying out of executions against perceived enemies of the revolution. During the peak of their influence, the sans-culottes were seen as the truest and most authentic sons of the French Revolution, held up as living representations of the revolutionary spirit. During the height of revolutionary fervor, such as during the Reign of Terror when it was dangerous to be associated with anything counter-revolutionary, even public functionaries and officials actually from middle or upper-class backgrounds adopted the clothing and label of the sans-culottes as a demonstration of solidarity with the working class and patriotism for the new French Republic. But by early 1794, as the bourgeois and middle-class elements of the revolution began to gain more political influence, the fervent working-class radicalism of the sans-culottes rapidly began falling out of favour within the National Convention.
Teratogenicity The teratogenic effects of aflatoxin B1 in rabbits have been reported to include reduced fetal weights, wrist drop, enlarged eye socket, agenesis of caudal vertebrae, micropthalmia, cardiac defects, and lenticular degeneration, among others. Immunotoxicity Studies in fish showed aflatoxin B1 to have significant immunosuppressive effects including reduced serum total globulin and reduced bactericidal activities.
In addition to the classical nuclear AR, bicalutamide has been assessed at the membrane androgen receptors (mARs) and found to act as a potent antagonist of ZIP9 (IC50 = 66.3 nM), whereas it does not appear to interact with GPRC6A. The affinity of bicalutamide for the AR is relatively low as it is approximately 30 to 100 times lower than that of DHT, which is 2.5- to 10-fold as potent as an AR agonist as testosterone in bioassays and is the main endogenous ligand of the receptor in the prostate gland. However, typical clinical dosages of bicalutamide result in circulating levels of the drug that are thousands of times higher than those of testosterone and DHT, allowing it to powerfully prevent them from binding to and activating the receptor. This is especially true in the case of surgical or medical castration, in which testosterone levels in the circulation are approximately 95% reduced and DHT levels in the prostate gland are about 50 to 60% reduced. In women, levels of testosterone are substantially lower (20- to 40-fold) than in men, so much smaller doses of bicalutamide (e.g., 25 mg/day in the hirsutism studies) are necessary. Blockade of the AR by bicalutamide in the pituitary gland and hypothalamus results in prevention of the negative feedback of androgens on the hypothalamic–pituitary–gonadal axis (HPG axis) in males and consequent disinhibition of pituitary luteinizing hormone (LH) secretion. This, in turn, results in an increase in circulating LH levels and activation of the gonadal production of testosterone and by extension production of estradiol.
Sources: en.wikipedia.org
It is registered as a pharmaceutical product in Russia, where it is typically supplied as a nasal solution. In most other countries it is not an approved drug and is traded as a research chemical instead. Approval status depends entirely on the jurisdiction involved.
Most published work uses intranasal administration, matching the route of the registered Russian formulation. Some animal experiments use intravenous or intraperitoneal injection. The route matters because the intact peptide is cleared rapidly from blood, so exposure differs between methods.
A purity value describes the share of the powder accounted for by the target peptide, usually by high-performance liquid chromatography. It does not confirm that the sequence is correct, which requires mass spectrometry or amino acid analysis. Purity and identity are separate checks.
电喷雾或基质辅助激光解吸电离质谱是常用手段,测得的质子化离子质荷比可换算为分子量。结果与理论值落在合理误差内,才支持结构一致的判断。