This is a working overview of ACTH(4-10), written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-07-05 and is reviewed periodically as new material appears.
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.
Regulatory status varies sharply by country. Semax is registered for medical use in Russia, where it appears in formularies as a nasal solution, and it also holds registration in a small number of neighbouring states. It has no approval from the United States Food and Drug Administration or the European Medicines Agency, and it is not a scheduled controlled substance in most jurisdictions. Elsewhere it circulates mainly as laboratory material, so purity documentation comes from suppliers rather than from a national pharmacopoeia.
Semax is a synthetic peptide created in the Soviet Union during the early 1980s by researchers working in Moscow. It was built from the short adrenocorticotropic hormone fragment known as ACTH(4-10), and the chain was then extended with three additional amino acids. The resulting molecule was named semax and entered clinical use in Russia in 1994. It is generally described as a nootropic and neuroprotective agent rather than as a hormone analogue.
| Property | Value | Notes |
|---|---|---|
| Typical purity | 95% or higher | By reversed-phase HPLC area |
| Identity method | Electrospray mass spectrometry | Confirms molecular mass |
| Purity method | Reversed-phase HPLC | Detection near 214 nm |
| Primary degradation | Methionine oxidation | Sulfoxide product, +16 Da |
| Solution storage | 2-8 °C, short term | Aliquot to avoid freeze-thaw |
Pharmacokinetic accounts emphasize rapid breakdown. After intravenous dosing the intact peptide disappears from blood within minutes, and nasal delivery produces low but measurable concentrations. Metabolites rather than the parent molecule may account for part of the observed activity, although the relative contribution is unresolved. Dosing in the literature varies widely and no optimal schedule has been agreed. These gaps are regularly cited as a reason the findings have not produced broad clinical adoption beyond the original research setting.
Proposed mechanisms center on neurotrophic signaling rather than on classical melanocortin receptor activation. Rodent experiments have reported shifts in the expression of brain-derived neurotrophic factor and nerve growth factor after administration, together with changes in the associated receptor systems. Several authors argue that the peptide acts largely through its degradation products and their interaction with peptidergic pathways, but this remains a hypothesis rather than a settled finding. No single molecular target has been identified in a way that the field broadly accepts.
Published research covers ischemic stroke, traumatic brain injury, cognitive impairment, optic nerve conditions and attention-related measures. Much of the human evidence comes from small trials conducted in one country, which limits how far the results generalize. Animal models supply the larger share of the data, and effects seen in rodents do not transfer automatically to people. Reviews have noted that methodological reporting is often incomplete, making it difficult to pool results or compare treatment schedules across studies.
The C-terminal Pro-Gly-Pro extension is not incidental. Proline-rich tails are known to resist several common peptidases, and the published literature attributes the longer half-life of Semax, relative to unmodified ACTH fragments, to this feature. The modification also removes the melanocyte-stimulating and corticosteroidogenic activity that characterizes longer ACTH-derived sequences. Because the molecule is small and hydrophilic, it is typically formulated as an aqueous solution for intranasal or parenteral delivery. Acetylation or amidation at the termini appears in closely related research peptides and shifts the mass by a fixed increment.
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.
Identity and purity are commonly assessed by reversed-phase high-performance liquid chromatography, with ultraviolet detection near 214 nanometers for the peptide backbone. Mass spectrometry, either electrospray or matrix-assisted laser desorption, confirms molecular mass and detects truncation or modification products. Amino acid analysis can verify composition. Because the sequence contains no strongly absorbing aromatic residue apart from phenylalanine, detection wavelengths are chosen carefully. Purity values above 95 percent are typical for research-grade material.
Quality documentation for research-grade peptide usually includes a certificate of analysis stating purity, identity, and residual counterion content. Batch-to-batch variation in purity and salt form is a recognized issue, and comparisons across suppliers require attention to the exact counterion, for example acetate versus trifluoroacetate. Sequence verification by tandem mass spectrometry provides stronger evidence than a single mass measurement. For any study reporting biological results, the analytical method and the measured purity should be stated explicitly. Independent verification of supplier claims is considered good practice.
Semax is a synthetic seven-amino-acid peptide whose sequence extends the ACTH(4-10) fragment with a C-terminal proline-glycine-proline tripeptide. The commonly cited sequence is Met-Glu-His-Phe-Pro-Gly-Pro, giving a molecular formula near C37H51N9O10S and a molecular weight close to 813.9 g/mol. It belongs to the broader class of synthetic ACTH fragments studied for central nervous system effects rather than for adrenal steroid stimulation. In practice the material appears as a lyophilized white powder for laboratory work or as a dilute saline solution in clinical settings.
Development is attributed to researchers at the Institute of Molecular Genetics in Moscow during the early 1980s, building on earlier Soviet work with ACTH fragments. Russian regulatory approval followed for intranasal use, and the compound has remained commercially available there for decades. Most published human data originate from Russian and, later, some Eastern European clinical reports, which are not always accessible in English translation. Outside that region the material is generally handled as a research chemical rather than a licensed medicine.
Regulatory status differs sharply between jurisdictions. In Russia the peptide is registered as a prescription nasal preparation, while agencies such as the United States Food and Drug Administration have not approved it for any indication. Products sold elsewhere are typically labeled for laboratory research only, and such labels shift responsibility for safe handling to the purchaser. Because the same name covers pharmaceutical-grade nasal drops and bulk research powder, identity and purity documentation becomes the main practical concern when comparing sources.
The risk of having a myocardial infarction increases with older age, low physical activity, and low socioeconomic status. Heart attacks appear to occur more commonly in the morning hours, especially between 6 am and noon. Evidence suggests that heart attacks are at least three times more likely to occur in the morning than in the late evening. Shift work is also associated with a higher risk of MI. One analysis has found an increase in heart attacks immediately following the start of daylight saving time. Women who use combined oral contraceptive pills have a modestly increased risk of myocardial infarction, especially in the presence of other risk factors. The use of non-steroidal anti-inflammatory drugs (NSAIDs), even for as short as a week, increases risk. Endometriosis in women under the age of 40 is an identified risk factor. Patients with intravenous devices (such as a PICC line, Central Venous Catheter, and ECMO, among others) have an increased risk of DVT and thrombosis, therefore increasing the risk of a myocardial infarction and other problems caused by blood clots such as strokes. Air pollution is also an important modifiable risk. Short-term exposure to air pollution such as carbon monoxide, nitrogen dioxide, and sulfur dioxide (but not ozone) has been associated with MI and other acute cardiovascular events. For sudden cardiac deaths, every increment of 30 units in Pollutant Standards Index correlated with an 8% increased risk of out-of-hospital cardiac arrest on the day of exposure. Extremes of temperature are also associated.
=== Reunion === The Doobies did not work together for the next five years, though various members got together in different configurations for annual Christmas season performances for the patients and staff at the Stanford Children's Hospital in the Bay area. Simmons released a commercially disappointing solo album, Arcade, in April 1983. During the mid-1980s, Johnston toured U.S. clubs with a band called Border Patrol, which did not release any recordings. Hossack and (briefly) Simmons worked with the group. Around 1986, Johnston and Simmons began working on an album together (according to a 1989 interview with Simmons) but abandoned the project soon after with no known finished tracks. In 1983, Knudsen and McFee formed the band Southern Pacific and recorded four albums that found success in the country charts (former Creedence Clearwater Revival bassist Stu Cook joined the band in 1986 and former Pablo Cruise guitarist David Jenkins in 1988). Out of print for many years, Simmons' Arcade was reissued on compact disc in 2007 by specialty label Wounded Bird Records, which is also the home of Southern Pacific's and Tom Johnston's catalogs. Post-Doobies, McDonald became established as a solo artist. His voice dominated adult contemporary radio throughout the 1980s, and he experienced a renaissance of popularity in the 21st century as an interpreter of Motown classics. The reformation of the Doobie Brothers was not intentional. On a personal quest for a worthy cause and after conquering his drug addiction, Knudsen became active in the Vietnam Veterans Aid Foundation.
Sulfur (specifically octasulfur, S8) is used in pharmaceutical skin preparations for the treatment of acne and other conditions. It acts as a keratolytic agent and also kills bacteria, fungi, scabies mites, and other parasites. Precipitated sulfur and colloidal sulfur are used, in form of lotions, creams, powders, soaps, and bath additives, for the treatment of acne vulgaris, acne rosacea, and seborrhoeic dermatitis. Many drugs contain sulfur. Early examples include antibacterial sulfonamides, known as sulfa drugs. A more recent example is mucolytic acetylcysteine. Sulfur is a part of many bacterial defense molecules. Most β-lactam antibiotics, including the penicillins, cephalosporins and monobactams contain sulfur.
The Cortlandt Street station on the New York City Subway's IRT Broadway–Seventh Avenue Line was also in close proximity to the World Trade Center complex, and the entire station, along with the surrounding track, was reduced to rubble. The station was rebuilt and reopened to the public on September 8, 2018.
== Cherenkov counting == High-energy beta emitters, such as phosphorus-32 and yttrium-90 can also be counted in a scintillation counter without the cocktail, instead using an aqueous solution containing no scintillators. This technique, known as Cherenkov counting, relies on Cherenkov radiation being detected directly by the photomultiplier tubes. Cherenkov counting benefits from the use of plastic vials which scatter the emitted light, increasing the potential for light to reach the photomultiplier tube.
Sources: en.wikipedia.org
==== US policy vs EU policy ==== The US Food and Drug Administration (FDA) approves the use of meloxicam in cats only in injectable form and only as a one-time injection given before surgery. It does not approve meloxicam oral suspension for cats and it does not approve meloxicam spray for cats because after reviewing numerous reports of meloxicam side effects in cats, it has identified many cases of acute renal failure and death and has added the following boxed warning to the prescription label: "Repeated use of meloxicam in cats has been associated with acute renal failure and death. Do not administer additional injectable or oral meloxicam to cats. See Contraindications, Warnings, and Precautions for detailed information." In contrast, in the European Union and other continents or countries, the use of the drug in cats is allowed with no such warning. The product instruction leaflet for meloxicam for cats in the form of oral suspension 0.5 mg/ml states that: "Typical adverse reactions of NSAIDs such as loss of appetite, vomiting, diarrhoea, faecal occult blood, apathy, and renal failure have occasionally been reported. These side effects are in most cases transient and disappear following termination of the treatment but in very rare cases may be serious or fatal."
An advertising poster featuring a picture of Michelangelo's David is removed from the Glasgow Subway at the request of the owners of the advertising space because of its nudity. It is replaced with an edited version hiding the crotch region. 20 May – The Annual General Meeting of the General Assembly of the Church of Scotland hears that hundreds of churches may have to close as a result of falling numbers of attendees and income. 21 May – Ten people are injured, and two are taken to hospital, after a bus crashes into a bridge in Glasgow and has its roof torn off. 22 May The Scottish Government offers junior doctors in Scotland a 14.5% pay rise. Margaret Ferrier loses her appeal against a proposed 30 day ban from the House of Commons over her breach of COVID-19 rules in September 2020. 24 May Following a hearing at the High Court in Edinburgh, Rhys Bennett is sentenced to life imprisonment with a minimum of 24 years for the rape and murder of Jill Barclay as she walked home in Aberdeen in September 2022. A group of eight former SNP councillors in North Lanarkshire form a new political party, Progressive Change NL, which becomes North Lanarkshire Council's second largest opposition party. 25 May – Responding to the outcome of a review of Police Scotland, its chief constable, Sir Ian Livingstone, says the force is institutionally sexist, racist and discriminatory.
=== Natural occurrence === Hawthorn flowers have a heavy, complicated scent, the distinctive part of which is triethylamine, which is also one of the first chemicals produced by a dead human body when it begins to decay. Due to the scent, it is considered unlucky in British culture to bring hawthorn into a house. Gangrene and semen are also said to possess a similar odour.
In order to better assess radiation protection, the number of X-ray examinations, including the dose, has been recorded annually in Germany since 2007. However, the Federal Statistical Office does not have complete data for conventional X-ray examinations. In 2014, the total number of X-ray examinations in Germany was estimated to be about 135 million, of which about 55 million were dental X-ray examinations. The average effective dose from x-ray examinations per inhabitant in Germany in 2014 was about 1.55 mSv (about 1.7 x-ray examinations per inhabitant per year). The proportion of dental X-rays is 41%, but accounts for only 0.4% of the collective effective dose. In Germany, Section 28 of the X-ray Ordinance (RöV) has required since 2002 that the attending physician must have an X-ray pass available for X-ray examinations and offer it to the patient. The pass contains information about the patient's X-rays to avoid unnecessary examinations and to allow comparison with previous images. With the entry into force of the new Radiation Protection Ordinance on December 31, 2018, this obligation no longer applies. In Austria and Switzerland, x-ray passports have so far been available voluntarily. In principle, there must always be both a justifiable indication for the use of X-rays and the informed consent of the patient. In the context of medical treatment, informed consent refers to the patient's agreement to all types of interventions and other medical measures. § 630d Act of (in German)
== Select publications == Meindl, Kathrin; Schmiederer, Timo; Schneider, Kathrin; Reicke, Andreas; Butz, Diane; Keller, Simone; et al. (February 2010). "Labyrinthopeptine – eine neue Klasse carbacyclischer Lantibiotika". Angewandte Chemie (in German). 122 (6): 1169–1173. doi:10.1002/ange.200905773. Schadt, Heiko S.; Schadt, Simone; Oldach, Florian; Süssmuth, Roderich D. (February 18, 2009). "2-Amino-2-deoxyisochorismate Is a Key Intermediate in Bacillus subtilis p-Aminobenzoic Acid Biosynthesis". Journal of the American Chemical Society. 131 (10). doi:10.1021/ja809283u. Dettner, Frank; Hänchen, Anne; Schols, Dominique; Toti, Luigi; Nußer, Antje; Süssmuth, Roderich D. (February 2009). "Totalsynthese des antiviralen Peptidantibiotikums Feglymycin". Angewandte Chemie (in German). 121 (10): 1888–1893. doi:10.1002/ange.200804130. Bister, Bojan; Bischoff, Daniel; Ströbele, Markus; Riedlinger, Julia; Reicke, Andreas; Wolter, Falko; et al. (May 2004). "Abyssomicin C—A Polycyclic Antibiotic from a Marine Verrucosispora Strain as an Inhibitor of the p ‐Aminobenzoic Acid/Tetrahydrofolate Biosynthesis Pathway". Angewandte Chemie International Edition. 43 (19): 2574–2576. doi:10.1002/anie.200353160. Bister, Bojan; Bischoff, Daniel; Nicholson, Graeme J.; Valdebenito, Marianne; Schneider, Kathrin; Winkelmann, Günther; et al. (August 2004). "The structure of salmochelins: C-glucosylated enterobactins of Salmonella enterica §". Biometals. 17 (4): 471–481. doi:10.1023/B:BIOM.0000029432.69418.6a.
Sources: en.wikipedia.org
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.
In solution, hydrolysis of peptide bonds and oxidation of the methionine residue are the principal concerns. Oxidation converts methionine to its sulfoxide form, shifting the mass by sixteen daltons. Both processes are slowed by cold storage and by avoiding alkaline conditions.
A certificate documents what the supplier measured on a specific lot, not how a laboratory will use the material. Independent verification of identity and purity is common practice. Acceptance criteria should be defined before a batch is ordered.
Registered medical products are most often 0.1% nasal drops. Research suppliers ship lyophilized powder, usually in milligram quantities, which is dissolved before use. The active peptide is the same in both cases; presentation and excipients differ.