If you have been reading about ACTH fragment 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 2026-02-17. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide | ACTH(4-7) analogue |
| Sequence | Met-Glu-His-Phe-Pro-Gly-Pro | Free N terminus, unmodified side chains |
| Molecular weight | 813.9 Da | Free base; salt forms differ |
| Appearance | White to off-white powder | Lyophilised solid |
| Solubility | Freely soluble in water | Hydrophilic; polar solvents preferred |
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.
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。
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.
The compound is registered in Russia as a pharmaceutical product, most commonly formulated as a nasal solution, and has been used in that setting since the 1990s. Outside that jurisdiction it is generally handled as a research chemical rather than an approved medicine. Regulatory status therefore differs sharply between countries, and material sold internationally may not correspond to the Russian pharmaceutical formulation. Documentation with commercial samples is typically limited to a certificate of analysis covering purity and identity, not clinical status or local legal classification.
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.
In the 1980s, Mister Donut was the largest competitor to Dunkin'. On March 31, 1987, Elie G. Saheb and his business associates acquired the trademark rights for Mister Donut in the United Kingdom and afterwards opened a Mister Donut pilot store and bakery in Fulham, London. On May 2, 1988, the Mister Donut franchise sold the trademark rights for the European market at large. By the 1980s, Mister Donut had over 550 stores in the United States and Canada. In 1989, the British corporate giant Allied-Lyons plc acquired Dunkin' Donuts from Rosenberg for a reported £196 million. After becoming a subsidiary of Allied-Lyons, Dunkin' Donuts immediately acquired Mister Donut from International Multifoods. Mister Donut stores were offered the option to convert to Dunkin', while all remaining Mister Donut franchises in the rest of the world started being operated on their own such as in Japan and El Salvador. Mister Donut sold its Middle East trademarks on October 14, 1995. In July 2005, Allied-Lyons was acquired by Pernod Ricard SA. On December 12, 2005, Pernod Ricard announced that it had agreed to sell Dunkin' Brands, which owned Dunkin' and Mister Donut, to a consortium of three US private equity firms (Thomas H. Lee Partners, the Carlyle Group and Bain Capital LLP) for US$2.43 billion. The closing of the sale occurred on March 1, 2006. In August 2012, Dunkin' Brands became completely independent of the private equity firms. As of 2017, only one Mister Donut store remains in the United States, in Godfrey, Illinois (outside of St. Louis), while there were 10,000 stores worldwide.
=== Electrophile === Vinyl halides are common coupling partners in the Stille reaction, and reactions of this type are found in numerous natural product total syntheses. Normally, vinyl iodides and bromides are used. Vinyl chlorides are insufficiently reactive toward oxidative addition to Pd(0). Iodides are normally preferred: they will typically react faster and under milder conditions than will bromides. This difference is demonstrated below by the selective coupling of a vinyl iodide in the presence of a vinyl bromide.
== Release == Portal was first released as part of The Orange Box for Windows and Xbox 360 on October 10, 2007, and for the PlayStation 3 on December 11, 2007. In addition to Portal, The Orange Box includes Half-Life 2 and its two add-on episodes, as well as Team Fortress 2. Portal's inclusion within The Orange Box was considered an experiment by Valve; having no idea of the success of Portal, the bundle provided it a "safety net" via means of these other games. Portal was kept to a modest length in case the game did not go over well with players. The game was released as a standalone retail product on April 9, 2008, with the Windows version also available as a download through Steam. In January 2008, Valve released a special demo titled Portal: The First Slice, free to any Steam user using Nvidia graphics hardware, as part of a collaboration between the two companies. The demo comes packaged with Half-Life 2: Deathmatch, Peggle Extreme, and Half-Life 2: Lost Coast. The demo includes test chambers 00 to 10 (eleven in total). Valve has since made the demo available to all Steam users. Portal is the first Valve-developed game to be added to the OS X-compatible list of games available on the launch of the Steam client for Mac on May 12, 2010, supporting Steam Play, in which buying the game on Macintosh or Windows computer makes it playable on both. As part of the promotion, Portal was offered as a free game for any Steam user during the two weeks following the Mac client's launch. Within the first week of this offer, over 1.5 million copies were downloaded through Steam.
Membrane separation processes operate without heating and therefore use less energy than conventional thermal separation processes such as distillation, sublimation, or crystallization. The separation process is purely physical and both fractions (permeate and retentate) can be obtained as useful products. Cold separation using membrane technology is widely used in the food technology, biotechnology and pharmaceutical industries. Furthermore, using membranes enables separations to take place that would be impossible using thermal separation methods. For example, it is impossible to separate the constituents of azeotropic liquids or solutes which form isomorphic crystals by distillation or recrystallization, but such separations can be achieved using membrane technology. Depending on the type of membrane, selective separation of certain individual substances or substance mixtures is possible. Important technical applications include the production of drinking water by reverse osmosis. In waste water treatment, membrane technology is becoming increasingly important. Ultra/microfiltration can be very effective in removing colloids and macromolecules from wastewater. This is needed if wastewater is discharged into sensitive waters especially those designated for contact water sports and recreation. About half of the market is in medical applications such as artificial kidneys to remove toxic substances by hemodialysis and as artificial lung for bubble-free supply of oxygen in the blood.
Sources: en.wikipedia.org
Disuccinimidyl suberate (DSS) is a six-carbon lysine-reactive non-cleavable cross-linking agent. It consists of functional groups It is a homobifunctional N-hydroxysuccinimide (NHS) ester formed by carbodiimide-activation of carboxylate molecules, with identical reactive groups at either end. The reactive groups are separated by a spacer and in this molecule it is a six carbon alkyl chain. This reagent is mainly used to form intramolecular crosslinks and preparation of polymers from monomers. It is ideal for receptor ligand cross-linking. DSS is reactive towards amine groups (primary amines) at pH 7.0-9.0. It is membrane permeable, therefore permitting intracellular cross-linking, has high purity, is non-cleavable, and is water-insoluble (it must be dissolved in a polar organic solvent such as DMF or DMSO before addition to sample.) Its reaction specificity, reaction product stability, and lack of reaction by-products make it a commonly used cross-linking agent.
=== Research === TRH has been evaluated for the treatment of various neurological disorders. It has been attempted for treatment of various epileptic disorders. TRH has been shown to improve outcomes of CNS injuries in experimental models. Efficacy for the treatment ALS and spinal muscle atrophy has not been demonstrated. Many individuals with depression exhibit a blunted endocrine response to TRH due to unknown reasons, and the response is correlated with clinical outcomes. Involvement of TRH in the pathogenesis of depression has nevertheless not been well established. TRH has undergone research for its ostensible antidepressant properties, however, results regarding efficacy have been inconsistent. One study on a small sample of people with treatment-resistant depression found short-lived anti-depressant and anti-suicidal effects when TRH was administered intrathecally. An orally bioavailable prodrug is being researched. In 2012, the U.S. Army awarded a research grant to develop a TRH nasal spray for suicide prevention amongst veterans. TRH acts as a wakefulness-promoting agent, causing awakening from sleep or sedation.
=== Video games === The Persona series of games is heavily based on Jung's theories, representing the shadow, the persona, and archetype. The Nights into Dreams series of games is heavily based on Jung's theories. Jungian concepts are present in the Xeno series, including Xenogears; its reimagination as the Xenosaga trilogy; and a graphic novel, Perfect Works, published by the game's creator. The game Control is heavily influenced by Carl Jung's ideas, particularly synchronicity and shadow selves. Alan Wake takes inspiration from Carl Jung's ideas of archetype and individuation.
Active components such as oxygen scavengers, carbon-dioxide emitters, carbon-dioxide absorbers, and ethanol emitters can help establish or maintain a desired package atmosphere. Reduced-oxygen packaging requires product-specific safety controls. A low-oxygen environment may inhibit aerobic spoilage organisms while allowing some anaerobic microorganisms to grow. Product acidity, water activity, processing, refrigeration, storage time, and package integrity must be considered together.
=== Special requirement food === The Modular Operational Rations Enhancement (MORE) is issued as a supplement to meals for troops in extreme, demanding operational environments such as high-intensity training events. The Tailored Operational Training Meal (TOTM) first entered service in May 2001. It provides a lower calorie count (an average of 997 kilocalories) for less intensive training environments, such as classroom instruction. It replaces the earlier mess-hall bagged lunches, catered meals or field kitchens for field instruction. The TOTM allows troops to become familiar with the MRE and its contents without providing an excessive amount of calories to troops who will not necessarily burn them. It uses a transparent outer plastic bag with commercial markings rather than the MRE's tan plastic bag with standard markings. There are currently 3 different lists of twelve menus, making a total of 36 different meals. Each TOTM ration case is packed with a full menu of 12 assorted meals, weighs about 20 lbs (9 kg), and is 0.95 cubic feet (27 L). The TOTM has a more limited shelf-life than the MRE, with a duration of only 12 to 18 months. The Unitized Group Ration (UGR) is a ration much like the MRE, but expanded to feed large groups. It is the successor to the older A-ration, B-ration, and T-ration. It comes packed in sealed metal trays that are heated and then opened. The Food Packet, Survival, General Purpose, Improved (FPSGPI) is given to pilots and other servicemembers that may require a small, extremely portable food ration for emergencies.
Sources: en.wikipedia.org
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.
It contains the 4-7 fragment of adrenocorticotropic hormone extended at the C terminus. That truncation removes the region associated with steroidogenic activity. The design intent was to keep neurotrophic properties while avoiding full hormonal effects.
No natural source of the intact heptapeptide is known. It is produced by solid-phase peptide synthesis. Some related ACTH fragments arise as hormone processing products, but the Pro-Gly-Pro extension is a designed addition rather than a natural sequence.
It is associated with the melanocortin receptor family, particularly subtypes found in the central nervous system. This interaction is separate from the adrenal pathway activated by full-length ACTH.