This is a working overview of lyophilized powder, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-04-29 and is reviewed periodically as new material appears.
The proposed mechanism centres on neurotrophic signalling rather than direct receptor activation. Semax is reported to increase expression of brain-derived neurotrophic factor and nerve growth factor in several brain regions, and to shift the balance between excitatory and inhibitory neurotransmitter systems. Interaction with melanocortin receptors has been suggested because of the parent ACTH fragment. Many of these findings come from rodent studies, and the extent to which they translate to human physiology remains an open question.
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.
Identity and purity are established with standard peptide methods. Reversed-phase HPLC with ultraviolet detection near 214 nm resolves the parent peak from deletion and truncation byproducts, and reports typically quote a main-peak percentage. Mass spectrometry by electrospray or MALDI-TOF confirms the expected molecular mass, while amino acid analysis or peptide mapping can verify composition when the sequence itself is in question. A certificate of analysis that pairs a chromatogram with a mass spectrum is more informative than a purity figure alone. Counter-ion content and residual solvents are separate specifications and are frequently omitted.
Semax is normally supplied as a lyophilized powder, and that form is the most stable. Suppliers commonly recommend storage at -20 °C in a desiccated container protected from light, with short-term handling at room temperature limited to weighing and transfer. Powder that has absorbed moisture degrades faster, so vials should be warmed to ambient temperature before opening to prevent condensation on the contents. Hygroscopic behavior is typical of short hydrophilic peptides, and humidity control matters more than temperature alone for long-term retention.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C37H51N9O10S | Calculated for the free peptide |
| Molar mass | 813.9 g/mol | Anhydrous free base |
| Peptide class | Synthetic heptapeptide | ACTH(4-10) analogue |
| Parent fragment | ACTH(4-10) | Adrenocorticotropic hormone segment |
| Developmental origin | Institute of Molecular Genetics, Moscow | Work began in the 1980s |
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.
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.
Lyophilised powder is normally kept at -20 °C in a desiccated container, with some suppliers recommending -80 °C for long-term archival storage. Repeated freeze-thaw cycles are the most common cause of avoidable loss, so aliquoting before freezing reduces variability between working sessions. Dissolved peptide is far less stable than the dry solid and is usually prepared fresh or held briefly at 4 °C. Aqueous solutions support both hydrolysis of the backbone and oxidation of the N-terminal methionine, and these two routes dominate degradation under ordinary laboratory conditions.
各国监管态度分化明显。俄罗斯按处方药管理，部分东欧国家留有使用记录；欧盟与美国未批准其作为药物上市，市面流通品通常标注为研究用化学品。身份差异意味着标示含量、纯度与无菌性缺少统一核查。体育领域还牵涉反兴奋剂名录，跨境携带则受目的地药品法规约束。
Semax 是人工设计的七肽，序列为 Met-Glu-His-Phe-Pro-Gly-Pro，骨架取自促肾上腺皮质激素片段 ACTH(4-10)。它于二十世纪八十年代在苏联的分子遗传学研究机构内合成。设计目标是保留该片段与注意力和记忆相关的活性，同时剔除促皮质激素释放等内分泌作用。此后俄罗斯将其登记为药品并进入临床使用。
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.
Dissolution is normally performed in water, phosphate-buffered saline, or normal saline, since the peptide is freely soluble in aqueous media and is rarely handled with strong organic solvents. Solution pH should be kept near neutral, because extreme acidity or alkalinity accelerates backbone hydrolysis and encourages oxidation of the methionine side chain. Once dissolved, the material is less stable than the dry powder and is commonly divided into single-use portions and frozen. Buffers containing primary amines, such as Tris, are often avoided because of possible side reactions.
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.
=== Withdrawal and dependence === Withdrawal symptoms typically occur 1–2 days after abruptly stopping gabapentin (almost unambiguously due to extended use and during a very short-term rebound phenomenon) — similar to, albeit less intense than most benzodiazepines. Agitation, confusion and disorientation are the most frequently reported, followed by gastrointestinal complaints and sweating, and more rare tremor, tachycardia, hypertension and insomnia. In some cases, users experience withdrawal seizures after chronic or semi-chronic use in the absence of periodic cycles or breaks during repeating and consecutive use. All these symptoms subside when gabapentin is re-instated or tapered off gradually at an appropriate rate. On its own, gabapentin appears not to have a substantial addictive power. In human and animal experiments, it shows limited to no rewarding effects. The vast majority of people abusing gabapentin are current or former abusers of opioids or sedatives. In these persons, gabapentin can boost the opioid "high" as well as decrease commonly experienced opioid-withdrawal symptoms such as anxiety.
=== Quiboloy's arrest order and Duterte as KOJC administrator === On March 9, 2024, Duterte's longtime friend and Kingdom of Jesus Christ leader, Pastor Apollo Quiboloy, was ordered arrested by the United States Federal Bureau of Investigation after his conviction by a US District Court for alleged cases of sex trafficking, rape, fraud, and cash smuggling. No extradition request was received by the Marcos administration for Quiboloy's arrest, although a probe in the Senate was previously initiated on January 23 by Senator Risa Hontiveros, who invited Quiboloy to attend the hearings. Quiboloy demanded a fair trial as a requirement to attend, though this was rebuked by Hontiveros and Marcos. Claiming his life was under threat through what he described as a connivance between Marcos and the US government, Quiboloy went into hiding and designated Duterte as administrator of his ministry's properties. After Quiboloy refused to attend the hearings, Hontiveros cited him in contempt and recommended the Senate President to order his arrest. Arrest orders for Quiboloy were issued by the Pasig Regional Trial Court despite the efforts of Senators Robin Padilla, Cynthia Villar, and Bong Go to oppose the move. Four separate raids were eventually held in Quiboloy's properties in Davao City; though Quiboloy was not found, the raids were criticized by Duterte and his allies for its "excessive [and] unnecessary force" involving several units of police and military personnel "in full battle gear". KOJC members gathered in a rally in Liwasang Bonifacio calling for justice for Quiboloy.
== Computing and the Internet == The macOS and Linux operating systems are not immune to malware such as trojan horses or computer viruses. Specialized malware designed to attack those systems does exist (see Linux malware). However, the vast majority of viruses are developed for Microsoft Windows due to its larger market share. The deep web is not primarily full of pornography, illegal drug trade websites, and stolen bank details. This information is primarily found in a small portion of the deep web known as the "dark web". Much of the deep web consists of academic libraries, databases, and anything that is not indexed by normal search engines, including most private email accounts and direct messages. Private browsing (such as Chrome's "Incognito Mode") does not protect users from being tracked by websites, governments, or one's internet service provider (ISP), nor does it hide one's information when using devices or networks owned or maintained by one's employer, school, or other entity, such as a coffee shop. Such entities can still use information such as IP addresses and user accounts to uniquely identify users. Private browsing also does not provide additional protection against viruses or malware. It is usually only a feature to not record browsing and searching history on the browser. Submerging a phone in rice after it has suffered from water damage has not been shown to be effective in repairing it.
As such, feeling is only one of the conditions for craving (another one is ignorance). Therefore, in this Buddhist view of causality, nothing has a single cause. Bodhi agrees with this, stating that not all conditional relations in dependent arising are based on direct causal necessitation. While in some cases there is a direct necessary relationship between the phenomena outlined in the lists (birth will always lead to death), in other cases there is not. This is an important point because as Bodhi notes, "if dependent arising described a series in which each factor necessitated the next, the series could never be broken," and liberation would be impossible.
=== Oxidative addition === Oxidative addition to the 14-electron Pd(0) complex is proposed. This process gives a 16-electron Pd(II) species. It has been suggested that anionic ligands, such as OAc, accelerate this step by the formation of [Pd(OAc)(PR3)n]−, making the palladium species more nucleophillic. In some cases, especially when an sp3-hybridized organohalide is used, an SN2 type mechanism tends to prevail, yet this is not as commonly seen in the literature. However, despite normally forming a cis-intermediate after a concerted oxidative addition, this product is in rapid equilibrium with its trans-isomer.
Sources: en.wikipedia.org
Portal is a 2007 puzzle-platform game developed and published by Valve. It was originally released in a bundle, The Orange Box, for Windows, Xbox 360 and PlayStation 3, and has been ported to other systems, including Mac OS X, Linux, Android (via Nvidia Shield), and Nintendo Switch. Portal is a first person game. It consists primarily of a series of puzzles that must be solved by teleporting the player's character and simple objects using the "Aperture Science Handheld Portal Device", also referred to as the "portal gun", a device that can create portals between locations in the puzzles. The player character, Chell, is challenged and taunted by an artificial intelligence construct named GLaDOS (Genetic Lifeform and Disk Operating System) to complete each puzzle in the Aperture Science Enrichment Center using the portal gun with the promise of receiving cake when all the puzzles are completed. The Source engine's physics system allows kinetic energy to be retained through portals, requiring creative use of portals to maneuver through the test chambers. This gameplay element is based on a similar concept from the game Narbacular Drop; many of the team members from the DigiPen Institute of Technology who worked on Narbacular Drop were hired by Valve for the creation of Portal. Portal was acclaimed as one of the most original games of 2007, despite some criticism for its short duration. It received praise for its originality, unique gameplay, dark story and sense of comedy.
EOSA Promoting the safe use of Ethylene Oxide for Sterilization WebBook page for C2H4O National Institute for Occupational Safety and Health – Ethylene Oxide Topic Page CDC – NIOSH Pocket Guide to Chemical Hazards EOSA memo about Ethylene Oxide (EtO) facts Archived 15 October 2017 at the Wayback Machine
He continued updating this publication to 2010, and it with its research documents and notes, including about half a million press cuttings, is now archived at the Bishopsgate Institute. William Rothenstein (29 January 1872 – 14 February 1945), painter, printmaker, draughtsman, lecturer, writer on art; wrote several critical books and pamphlets, including Goya; the first English monograph on the artist), A Plea for a Wider Use of Artists & Craftsmen and Whither Painting; published three volumes of memoirs: Men and Memories, Vol I and II and Since Fifty. Men and Memories Volume I includes anecdotes about Oscar Wilde and many other friends of Rothenstein's, including Max Beerbohm, James Whistler, Paul Verlaine, Edgar Degas, and John Singer Sargent. Hannah Rothschild (born 22 May 1962), daughter of Jacob Rothschild, 4th Baron Rothschild, author, businesswoman, philanthropist and documentary filmmaker, has written screenplays and journalism, a biography and two novels; serves on charitable and financial boards and is first female to chair the Board of Trustees of the National Gallery in London;liaison trustee for the Tate Gallery;trustee of the Whitechapel Gallery;chair of Yad Hanadiv in Israel; directed films for Saturday Review, Arena and Omnibus; has written for The Times, The New York Times, The Observer, The Guardian, Daily Telegraph, Vanity Fair, Vogue, The Spectator and Harper's Bazaar, Financial Times, Elle, Washington Post and others.
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Sources: en.wikipedia.org
Semax is based on the ACTH(4-10) fragment, a seven-amino-acid segment of adrenocorticotropic hormone. The synthetic peptide retains the core sequence while removing regions associated with endocrine activity. This modification is intended to isolate effects on the nervous system.
It is registered for clinical use in Russia and a few other countries, typically as a nasal drop formulation. It does not hold approval from the United States Food and Drug Administration or the European Medicines Agency. Outside those markets it is generally handled as a research chemical.
The compound was developed in Moscow and the earliest studies were conducted there, so the primary literature is largely in Russian-language journals. Translation and indexing have been incomplete, which limits access for outside researchers. Independent groups have since published some work, but the total volume remains modest.
Each freeze-thaw cycle can degrade a fraction of the peptide and promote aggregation. Dividing a stock solution into single-use volumes removes repeated cycling as a variable. It also limits the time a thawed solution spends at room temperature.