If you have been reading about Electrospray ionization 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 2026-02-21. Numbers and descriptions here follow the published literature rather than marketing material.
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.
Stability depends heavily on physical state. Lyophilized powder held dry, cold and dark retains its content over long periods, whereas dissolved peptide begins to change within days at room temperature. The most cited degradation route is oxidation of the methionine residue, which converts the peptide to a sulfoxide form that elutes differently on chromatography. Hydrolysis of amide bonds and adsorption onto container walls contribute smaller losses. Buffers that exclude oxygen from the headspace slow the oxidation pathway, but no single condition prevents all change indefinitely.
Practical handling follows from those properties. Bulk material is best divided into single-use portions soon after receipt, because each thaw exposes the whole container to moisture and temperature cycling. Vials should be allowed to reach room temperature before opening to prevent condensation on the powder. Low-binding plasticware reduces loss of dilute solutions, and sterile filtration is used when a preparation must remain free of microbial growth. Records of batch number, reconstitution date and storage history are what allow a later analytical result to be interpreted meaningfully.
Identity and purity of Semax are established mainly by reversed-phase high-performance liquid chromatography coupled with mass spectrometry. The chromatographic trace gives a purity estimate as a percentage of total peak area, while electrospray or matrix-assisted laser desorption ionization confirms the molecular mass against the calculated value. Amino acid analysis and sequence-specific fragmentation provide further confirmation when a supplier's chain of custody is unclear. Vendors frequently quote a purity figure without stating the detection wavelength or the integration method, which limits how far one number can be compared with another.
| 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 |
Reported pharmacological work centers on neurotrophic signaling, including changes in BDNF and NGF expression in hippocampal tissue in animal models. Human data come largely from studies conducted in Russia, and how well those results generalize to other populations remains an open question. Regulatory status differs sharply by jurisdiction: Semax is a registered prescription medicine in Russia, while it holds no approved marketing status in the United States or the European Union. Outside such jurisdictions it is generally handled as a research chemical, which affects both documentation and quality expectations.
Semax is a synthetic heptapeptide whose sequence is Met-Glu-His-Phe-Pro-Gly-Pro. It was developed as a fragment analog of adrenocorticotropic hormone, modeled specifically on the ACTH(4-10) region. The first four residues reproduce that fragment, while a Pro-Gly-Pro tripeptide is appended at the C-terminus. Work on the compound originated in Russia, where it entered clinical use as an intranasal preparation. Its sequence places it among short regulatory peptides studied for effects on the central nervous system rather than on the adrenal axis.
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.
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。
该化合物于二十世纪八十年代在俄罗斯被开发，相关工作由俄罗斯科学院分子遗传学研究所的研究团队主导。开发目标并非复制 ACTH 的完整激素活性，而是寻找保留其神经作用方向、同时去除促肾上腺皮质激素释放效应的短肽片段。研究记录显示，这一方向促成了多个相关短肽的合成与筛选，而 Semax 是其中被研究最广泛的一个。当地文献常以 Семакс 这一名称指代它。
A recent study suggested "a multifaceted global strategy is needed to prevent substandard and falsified medicines especially in childrens, emphasizing that effective prevention requires strong regulatory enforcement, improved pharmaceutical supply chains, healthcare education, international collaboration, and access to quality medicines to reduce the associated health risks and disease burden. The study suggested two novel proposals not widely discussed before are (1) a Global Pediatric Drug Quality Index, to rank countries based on regulatory strength, testing capacity, and reporting systems for pediatric medicines, and (2) a Zero-Tolerance Supply Chain Protocol combining blockchain, community surveillance, and mini-labs to enforce transparency and prevent pediatric drug counterfeiting.
==== Construction and renovation ==== In a 2022 report on workplace lead exposure trends, the US CDC notes that construction is among the top four main industries at risk for lead exposure. In Ghana, workers who paint or spray/paint have been tested with the highest prevalence of elevated blood lead levels in a study conducted on blood lead levels in high-risk occupational groups. Amongst different paint usage in Iran, a small study found that car and building painters have elevated blood lead levels, in which car painters had higher blood lead levels than building painters.
The Office of the Cayman Island's Governor stated that the British government "recognizes the importance of regional security and is committed to providing advice and capacity building to our Cayman law-enforcement partners", highlighted the mutual defense alliance between the British and American governments, and emphasized organized crime as a common threat. The United States maintains two Forward Operating Locations (FOL) on the Dutch territories of Aruba and Curaçao, stemming from a 2000 treaty. In response to escalating tensions between Venezuela and the US, the Dutch have taken a neutral position, but say treaties must be honored. Dutch Defense Minister Ruben Brekelmans stated that the treaty "permits flights from Curaçao solely for surveillance, monitoring, and the detection of drug shipments. This consent applies only to unarmed flights". According to the Curacao Chronicle, the minister indicated that the approximate 1,000 soldiers in the Dutch Antilles, as well as the Dutch Caribbean Coast Guard and accompanying aircraft, could be used "if the situation escalates". On 19 September, Prime Minister Gilmar Pisas of Curaçao stated it would renew its treaty for the Curaçao-based FOL until at least 2 November 2026. The US expressed interest in establishing a temporary military radar base in Grenada in October. Critics urged Prime Minister Dickon Mitchell to deny the request, as they feared that the US strikes were a pretext for war with Venezuela, a nation that they say "has not done ... anything" to Grenada.
Chemist Gary Molander of the University of Pennsylvania described how "[d]ozens of biotechnology and drug companies were started" based on Hirschmann's developments and that "[t]he whole biotechnology field" and new classes of medicines, such as protease inhibitors for the treatment of AIDS, were established through his approach. As head of Merck's department of new lead discovery starting in 1971 and as senior vice president for basic research in chemistry starting in 1978, serving until the retirement age of 65, when he left the firm in 1987, Hirschmann played a pivotal role in the development of many of the firm's products. Among the medications he was involved with was the development of the antiparasitic Ivermectin used for the treatment of river blindness, the statin Mevacor for reducing cholesterol in patients at risk of cardiovascular disease, the beta-lactam-family broad-spectrum antibiotic Primaxin, the synthetic androgen Proscar used for the treatment of enlarged prostate and prostate cancer and of the ACE inhibitor Vasotec for treating hypertension. Following his departure from Merck, Hirschmann taught at the University of Pennsylvania and the Medical University of South Carolina until his retirement in 2006.
Sources: en.wikipedia.org
Abrupt discontinuation of SSRIs, especially after prolonged therapy, causes a withdrawal syndrome, which may include symptoms such as nausea and vomiting, headache, dizziness, chills, body aches, paresthesias, insomnia, and brain zaps. Serotonin reuptake inhibitors should not be abruptly discontinued after extended therapy, and whenever possible, should be tapered over several weeks to minimize discontinuation-related symptoms. SSRI-associated withdrawal symptoms are not typically referred to as a dependence syndrome. However, commentators have noted that such symptoms meet the definition of a physical and psychological dependence syndrome. Paroxetine may produce discontinuation-related symptoms at a greater rate than other SSRIs, though qualitatively similar effects have been reported for all SSRIs. Discontinuation effects appear to be less for fluoxetine, perhaps owing to its long half-life and the natural tapering effect associated with its slow clearance from the body. One strategy for minimizing SSRI discontinuation symptoms is to switch the patient to fluoxetine and then taper and discontinue the fluoxetine.
19 August – Kate Osborne, the MP for Jarrow and Gateshead East, is being investigated by the Independent Parliamentary Standards Authority for her spending on travel and subsistence costs, as well as "miscellaneous costs and financial assistance" following an operation. 20 August – James Harding, the BBC's former director of news, says the broadcaster should be protected from "political interference" following comments by Culture Secretary Lisa Nandy earlier in the year, when she appeared to call for the resignation of director-general Tim Davie. Former Conservative MP Sarah Atherton leaves the party, describing it as "impotent" and something that "no longer aligns" with her "values or ideology", and announces plans to stand in the 2026 Senedd election. 22 August – MSP Jeremy Balfour resigns from the Scottish Conservatives, saying the party has "fallen into the trap of reactionary politics" under the leadership of Russell Findlay. Dame Andrea Jenkyns, Zia Yusuf, Gawain Towler, Darren Grimes, Dan Barker and Paul Nuttall join Reform UK's governing board. 23 August – Nigel Farage tells The Times that a Reform government would introduce an Illegal Migration (Mass Deportation) Bill that would cost the UK £10bn to implement. 25 August – Richard Tice, Reform UK's energy spokesman, says the party would look at the potential of fracking if in government. 26 August – Safeguarding Minister Jess Phillips tells BBC News that the screening tool used to decide which domestic abuse victims get urgent support "doesn't work".
As a result of its very low Lewis basicity, it is often used as a low-temperature solvent/diluent for superacids like magic acid (FSO3H/SbF5), allowing for highly reactive species like tert-butyl cation to be observed spectroscopically at low temperature (though tertiary carbocations do react with SO2 above about −30 °C, and even less reactive solvents like SO2ClF must be used at these higher temperatures).
In 1964, Sanders sold KFC to a group of investors led by John Y. Brown Jr. and Jack C. Massey for US$2 million (around US$17 million in 2020). The contract included a lifetime salary for Sanders and the agreement that he would be the company's quality controller and trademark. The chain had reached 3,000 outlets in 48 countries by 1970. In July 1971, Brown sold the company to the Connecticut-based Heublein, a packaged food and drinks corporation, for US$285 million (around US$1.8 billion in 2020). Sanders died in 1980, his promotional work making him a prominent figure in American cultural history. By the time of his death, there were an estimated 6,000 KFC outlets in 48 countries worldwide, with $2 billion worth of sales annually. In 1982, Heublein was acquired by R. J. Reynolds, the tobacco giant. In July 1986, Reynolds announced the sale of KFC to PepsiCo for $850 million (around US$2.0 billion in 2020). The actual sale took place in early October for $840 million. PepsiCo made the chain a part of its restaurants division alongside Pizza Hut and Taco Bell. KFC entered the Chinese market in November 1987, with an outlet in Beijing. In 1991, the KFC name was officially adopted, although it had already been widely known by that initialism. Kyle Craig, president of KFC U.S., admitted the change was an attempt to distance the chain from the unhealthy connotations of "fried".
Chlorphenamine acts primarily as a potent H1 antihistamine. It is specifically a potent inverse agonist of the histamine H1 receptor. The drug is also commonly described as possessing weak anticholinergic activity by acting as an antagonist of the muscarinic acetylcholine receptors. The dextrorotatory stereoisomer, dexchlorpheniramine, has been reported to possess Kd values of 15 nM for the H1 receptor and 1,300 nM for the muscarinic acetylcholine receptors in human brain tissue. The smaller the Kd value, the greater the binding affinity of the ligand for its target. In addition to acting as an inverse agonist at the H1 receptor, chlorphenamine has been found to act as a serotonin reuptake inhibitor (Kd = 15.2 nM for the serotonin transporter). It has only weak affinity for the norepinephrine and dopamine transporters (Kd = 1,440 nM and 1,060 nM, respectively). A study found that dexchlorphenamine had Ki values for the human cloned H1 receptor of 2.67 to 4.81 nM while levchlorphenamine had Ki values of 211 to 361 nM for this receptor, indicating that dexchlorphenamine is the active enantiomer. Another study found that dexchlorphenamine had a Ki value of 20 to 30 μM for the muscarinic acetylcholine receptor using rat brain tissue while levchlorphenamine had a Ki value of 40 to 50 μM for this receptor, indicating that both enantiomers have very low affinity for it.
Sources: en.wikipedia.org
=== Emerging diseases === In most cases, microorganisms live in harmony with their hosts via mutual or commensal interactions. Diseases can emerge when existing parasites become pathogenic or when new pathogenic parasites enter a new host.
==== Iraq War ==== Hitchens employed the term "Islamofascist" and supported the Iraq War, causing his critics to consider him a "neoconservative". Hitchens, however, refused to embrace this designation, insisting, "I'm not any kind of conservative". In 2004, Hitchens stated that neoconservative support for US intervention in Iraq convinced him that he was "on the same side as the neo-conservatives" when it came to contemporary foreign policy issues, and characterized himself as an unqualified "supporter of Paul Wolfowitz." He referred to his associations as "temporary neocon allies". In this period he opined that "the Bush administration [...] has redefined the lazy term 'conservative' to mean someone who is impatient with the status quo." In the years after the fatwa issued against Salman Rushdie in response to his novel The Satanic Verses, Hitchens became increasingly critical of what he called "excuse making" on the left. At the same time, he was attracted to the foreign policy ideas of some on the Republican-right that promoted pro-liberalism intervention, especially the neoconservative group that included Paul Wolfowitz. Around this time, he befriended the Iraqi dissident and businessman Ahmed Chalabi. Hitchens argued the case for the Iraq War in a 2003 collection of essays entitled A Long Short War: The Postponed Liberation of Iraq, and participated in public debates on the topic with George Galloway, Scott Ritter, and his brother Peter Hitchens.
=== Clinical Services === BRT's Clinical Services division is licensed by the State of Maryland Department of Health and Mental Hygiene Archived 2006-01-30 at the Wayback Machine for Molecular Biology and Molecular Genetics and is registered under the US Department of Health and Human Services' Clinical Laboratory Improvement Amendments. Test offerings include Tuberculosis testing and Bone Marrow Engraftment (chimerism) monitoring. BRT’s tuberculosis (TB) testing is performed using the Interferon-gamma release assay T-SPOT.TB. This assay is recognized by the Centers for Disease Control and Prevention as a special TB blood test with an accuracy of diagnosing active TB >80%. Bone Marrow Engraftment monitoring assesses the relative ratio of donor and recipient cell populations in the post-transplant peripheral blood or bone marrow of the patient. BRT performs this test using STR analysis, the current "gold standard," yielding a sensitivity of 95–98%.
Carpipramine (Prazinil, Defekton) is an atypical antipsychotic used for the treatment of schizophrenia and anxiety in France and Japan. In addition to its neuroleptic and anxiolytic effects, carpipramine also has hypnotic properties. It is structurally related to both tricyclics like imipramine and butyrophenones like haloperidol.
=== Intellectual property === The first polio vaccine was never patented; some have argued that similar treatment of an effective COVID‑19 vaccine could enable fair distribution. Initially, negotiations at the World Trade Organization (WTO) on the issue of waiving patent rights were blocked for months by resistance by the US, Switzerland, Norway, and the EU. Initially one observer considered the US position unlikely to change, but as of April 2021 the US administration was discussing the issue and then reversed course and announced its support for a patent waiver for COVID-19 vaccines on 5 May 2021. 400 non-profit organizations and 115 members of the European Commission have signed a letter urging the United States and Europe to side with the WTO members in the global south.
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.
Suppliers normally quote a percentage of total chromatographic peak area, most often from reversed-phase HPLC. That figure says nothing about what the remaining percentage contains, and it depends on the detection wavelength used. A mass spectrometry result is a separate and stronger check on identity.