lyophilisation raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
This page was last updated on 2026-05-01 and is reviewed periodically as new material appears.
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.
Identity and purity are confirmed with reversed-phase high-performance liquid chromatography, typically monitored at 214 nanometres where the peptide bond absorbs. Mass spectrometry, either electrospray or MALDI-TOF, verifies molecular mass against the theoretical value and detects truncation or adduct formation. Amino acid analysis and peptide mapping provide additional confirmation when required. The most frequently reported impurities are deletion sequences from incomplete coupling, methionine sulfoxide from oxidation, and dimeric species formed through non-covalent aggregation. Impurity profiles depend strongly on the synthesis and purification route chosen by the producer.
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.
| 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 |
The compound was developed in the 1980s at the Institute of Molecular Genetics in Moscow, where it emerged from research on short ACTH fragments and their effects on the central nervous system. Russian pharmaceutical listings describe it as a nootropic and neuroprotective agent, most often formulated as nasal drops. It is not a marketed medicine in the United States or the European Union, and no pharmacopoeial monograph covers it. Consequently, most published clinical experience with the substance originates from a small number of research centres, mainly in Russia and neighbouring countries.
Pharmacological accounts link semax to melanocortin signalling and to modulation of neurotrophic factor expression, particularly brain-derived neurotrophic factor and nerve growth factor. Much of this evidence comes from rodent studies using intranasal delivery, a route chosen because it allows peptides to reach the central nervous system with limited systemic exposure. Whether the same mechanisms operate in humans at comparable magnitude remains an open question. The precise receptor or receptors responsible for the reported behavioural and neuroprotective effects have not been conclusively identified.
Clinical reports describe use in ischaemic stroke, transient ischaemic attack, optic nerve conditions, and cognitive complaints, but most of these studies are small and were conducted in a single region. Systematic reviews have generally described the evidence base as limited in size and variable in methodological quality. Randomised controlled data suitable for international regulatory assessment are scarce. As a result, major treatment guidelines outside Russia do not include the peptide, and interest in it remains largely research-driven rather than routine clinical.
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.
== Funding == The programme is funded through Thailand’s national budget, primarily under allocations from the Ministry of Education and the Ministry of Agriculture and Cooperatives. Annual budgets typically range between 10 and 15 billion baht depending on student enrolment and milk prices. In fiscal year 2024, the total cost was approximately 14 billion baht.
Liquid water is present on Earth, covering 71% of its surface. Liquid water is also occasionally present in small amounts on Mars. Scientists believe liquid water is present in the Saturnian moons of Enceladus, as a 10-kilometre thick ocean approximately 30–40 kilometers below Enceladus' south polar surface, and Titan, as a subsurface layer, possibly mixed with ammonia. Jupiter's moon Europa has surface characteristics which suggest a subsurface liquid water ocean. Liquid water may also exist on Jupiter's moon Ganymede as a layer sandwiched between high pressure ice and rock.
Funding for research into type 1 diabetes originates from the government, industry (e.g., pharmaceutical companies), and charitable organizations. Government funding in the United States is distributed via the National Institutes of Health, and in the UK via the National Institute for Health and Care Research or the Medical Research Council. The Juvenile Diabetes Research Foundation (JDRF), founded by parents of children with type 1 diabetes, is the world's largest provider of charity-based funding for type 1 diabetes research. Other charities include the American Diabetes Association, Diabetes UK, Diabetes Research and Wellness Foundation, Diabetes Australia, and the Canadian Diabetes Association.
=== Saxon era === A minster was founded in the 8th century at Westbury on Trym and is mentioned in a charter of 804. In 946 an outlaw named Leof killed Edmund I in a brawl at a feast in the royal palace at Pucklechurch, which lies about six miles from Bristol. The town of Bristol was founded on a low hill between the rivers Frome and Avon at some time before the early 11th century. The main evidence for this is a coin of Aethelred issued c. 1010. This shows that the settlement must have been a market town and the name Brycg stowe indicates "place by the bridge". It is believed that the Bristol L (the tendency for the local accent to add a letter L to the end of some words) is what changed the name Brycg stowe to the current name Bristol. It appears that St Peter's church, the remains of which stand in modern Castle Park, may have been another minster, possibly with 8th-century origins. By the time of Domesday the church held three hides of land, which was a sizeable holding for a mere parish church. The Anglo-Saxon Chronicle records that in 1052 Harold Godwinson took ship to Brycgstow and later in 1062 he took ships from the town to subdue the forces of Gruffydd ap Llywelyn of Wales, indicating the status of the town as a port. Brycg stowe was a major centre for the Anglo-Saxon slave trade. Men, women and children captured in Wales or northern England were traded through Bristol to Dublin as slaves. From there the Viking rulers of Dublin would sell them on throughout the known world.
Sources: en.wikipedia.org
One of their most challenging scenes made, was the opening scene of the first episode for which they depicted the nearly total destruction of New York City. For the creation of the effects, every department had to contribute to produce high-quality hyper-real 2D and 3D elements and detailed set extensions combined with matte paintings. Also, several shots involving dozens of high-resolution render layers, though it posed data management challenge.
=== Fossil record === The earliest widely accepted animal fossils are rather modern-looking cnidarians, possibly from around 580 million years ago, although fossils from the Doushantuo Formation can only be dated approximately. The identification of some of these as embryos of animals has been contested, but other fossils from these rocks strongly resemble tubes and other mineralized structures made by corals. Their presence implies that the cnidarian and bilaterian lineages had already diverged. Although the Ediacaran fossil Charnia used to be classified as a jellyfish or sea pen, more recent study of growth patterns in Charnia and modern cnidarians has cast doubt on this hypothesis, leaving the Canadian polyp Haootia and the British Auroralumina as the only recognized cnidarian body fossils from the Ediacaran. Auroralumina is the earliest known animal predator. Few fossils of cnidarians without mineralized skeletons are known from more recent rocks, except in Lagerstätten that preserved soft-bodied animals. A few mineralized fossils that resemble corals have been found in rocks from the Cambrian period, and corals diversified in the Early Ordovician. These corals, which were wiped out in the Permian–Triassic extinction event about 252 million years ago, did not dominate reef construction since sponges and algae also played a major part. During the Mesozoic era, rudist bivalves were the main reef-builders, but they were wiped out in the Cretaceous–Paleogene extinction event 66 million years ago, and since then the main reef-builders have been scleractinian corals.
However, Trump and Markwayne Mullin reverse this position the next day. Trump pays E. Jean Carroll $6.5 million, three years after being found liable of sexually assaulting her in the E. Jean Carroll v. Donald J. Trump lawsuit. New York becomes the first state to impose a moratorium on data centers. July 15 – 2026 Iran war: President Trump threatens attacks on Iranian power plants and bridges unless Iran resumes negotiations, while considering expanded military operations including the possible invasion of Kharg Island. CENTCOM reinstates its blockade of Iranian ports and conducts further strikes against coastal defences and missile facilities near the Strait of Hormuz. July 16 2026 Iran war: The White House maintains that Iran is still in talks with the US and hopes to negotiate an agreement. CENTCOM says it had expanded strikes into northern Iran on targets including military logistics infrastructure to "further degrade Iranian military capabilities". The Wisconsin Department of Health Services reports the first hospitalization of the summer in Wisconsin in connection with the cyclosporiasis outbreak. July 17 2026 Iran war: US-led coalition forces in Iraq intercept several drones above Erbil. The U.S. states that it struck Iran's infrastructure including subterranean arsenals for seventh consecutive night.
The breeder reactor as its name implies creates larger quantities of 239Pu or 233U (the fissile isotopes) than it consumes. The Clean And Environmentally Safe Advanced Reactor (CAESAR), a nuclear reactor concept that would use steam as a moderator to control delayed neutrons, will potentially be able to use 238U as fuel once the reactor is started with Low-enriched uranium (LEU) fuel. This design is still in the early stages of development.
== GLP-1 and neuropeptide Y multi-agonists == In 2023, researchers disclosed the discovery of multiple peptides that activated the GLP-1 receptor, neuropeptide Y receptor Y1, and neuropeptide Y receptor Y2. Since neuropeptide Y receptors were a previous anti-obesity target, it is hoped that the combination might be more efficacious than GLP-1 receptor agonists.
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.
Reversed-phase HPLC gives the main purity figure, most often with UV detection near 214 nanometres. Mass spectrometry then confirms the molecular mass. Together the two methods distinguish a correct sequence from a closely related impurity.