The short version of nootropic fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-02-17. Anything still debated is marked as such rather than presented as settled.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide (ACTH fragment analog) | Not a steroid; does not belong to the melanocortin agonist drugs by marketing category |
| Molecular formula | C37H51N9O10S (commonly cited) | Reported values vary slightly with salt and counter-ion content |
| Appearance | White to off-white lyophilized powder | A single batch may appear as a loose cake or fluffy solid |
| Solubility | Freely soluble in water and aqueous buffer | Stock solutions are usually prepared in sterile water or saline |
| Typical storage | −20 °C or below, desiccated and protected from light | Seal opened vials promptly to limit moisture uptake |
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.
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.
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.
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.
The parent fragment ACTH(4-10) carries the sequence Met-Glu-His-Phe-Arg-Trp-Gly. Semax replaces the arginine and tryptophan positions with a proline-glycine-proline tail, giving Met-Glu-His-Phe-Pro-Gly-Pro. That change removes residues associated with adrenal stimulation, so the peptide does not drive cortisol release the way full ACTH does. This distinction shapes how the compound is grouped in the literature, where it sits with neuropeptides and peptide neuromodulators rather than with corticosteroids.
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.
EBAC is the estimated blood alcohol concentration (in g/L) A is the mass of alcohol consumed (g). T is the amount of time during that alcohol was present in the blood (usually time since consumption began), in hours. β is the rate at which alcohol is eliminated, averaging around 0.15 g/L/hr. Vd is the volume of distribution (L); typically body weight (kg) multiplied by 0.71 L/kg for men and 0.58 L/kg for women although estimation using TBW is more accurate. A standard drink, defined by the WHO as 10 grams of pure alcohol, is the most frequently used measure in many countries. Examples:
=== Obesity === Octreotide has been used experimentally to treat obesity, particularly obesity caused by lesions in the hunger and satiety centers of the hypothalamus, a region of the brain central to the regulation of food intake and energy expenditure. The circuit begins with an area of the hypothalamus, the arcuate nucleus, that has outputs to the lateral hypothalamus (LH) and ventromedial hypothalamus (VMH), the brain's feeding and satiety centers, respectively. The ventromedial hypothalamus is sometimes injured by ongoing treatment for acute lymphoblastic leukemia or surgery or radiation to treat posterior cranial fossa tumors. With the ventromedial hypothalamus disabled and no longer responding to peripheral energy balance signals, "Efferent sympathetic activity drops, resulting in malaise and reduced energy expenditure, and vagal activity increases, resulting in increased insulin secretion and adipogenesis." "VMH dysfunction promotes excessive caloric intake and decreased caloric expenditure, leading to continuous and unrelenting weight gain. Attempts at caloric restriction or pharmacotherapy with adrenergic or serotonergic agents have previously met with little or only brief success in treating this syndrome." In this context, octreotide suppresses the excessive release of insulin and may increase its action, thereby inhibiting excessive adipose storage.
Cancers are found to attract and rely on immune suppressors such as regulatory T cells or other cells in the tumor microenvironment to decrease the response of immune cells. Further, reducing the activity of cytotoxic T cells by sustaining expression of inhibitory receptors limits the effectiveness of immune checkpoint inhibitors. Cancers can modify the tumor microenvironment itself, creating physical and biochemical barriers to immune attack. Abnormal vasculature is a prominent way of doing this. Tumors secrete factors that attract the growth of blood vessels (angiogenesis) that encourages further methods of nutrient transport, feeding the tumor. Additionally, cancer cells can produce nerve growth factor which causes healthy neurons to develop around and within tumors. This is promotes further tumor growth because nerves produce neurotransmitters 5HT that prompt tumor cell proliferation. Essentially solid tumors are able to create networks of feedback loops, hijacking healthy cells.
=== Names === Some humanoid or drone Culture citizens have long names, often with seven or more words. Some of these words specify the citizen's origin (place of birth or manufacture), some an occupation, and some may denote specific philosophical or political alignments (chosen later in life by the citizen themselves), or make other similarly personal statements. An example would be Diziet Sma, whose full name is Rasd-Coduresa Diziet Embless Sma da' Marenhide:
The white shark has a stocky, torpedo-shaped body with a short, cone-shaped snout. Its long gill slits do not reach around the head. It has a large triangular first dorsal fin, which partly lines up with the pectoral fins, and a tiny second dorsal fin. The tail fin has two lobes of similar size and a single ridge or keel, and the anal fin is tiny. The white shark has a countershaded coloration for camouflage; being dark on top, usually blue-gray or gray-brown, with a white underside. It also has black tips on the underside of the pectoral fins. There is evidence that the species can change pigments, adding dark pigment or melanin to blotches of white over the course of months. The skin is covered in dermal denticles (tooth-like scales), which are proportionally smaller than in other sharks and have a three-to-five-ridged surface, with each ridge having tips that point backwards.
Sources: en.wikipedia.org
One of the earliest patents for a "chain sawing machine" comprising a chain of links carrying saw teeth was granted to Frederick L. Magaw of Flatlands, New York, in 1883, apparently for the purpose of producing boards by stretching the chain between grooved drums. A later patent incorporating a guide frame was granted to Samuel J. Bens of San Francisco on January 17, 1905, his intent being to fell giant redwoods. The first portable chainsaw was developed and patented in 1918 by Canadian millwright James Shand. After he allowed his rights to lapse in 1930, his invention was further developed by what became the German company Festo in 1933. The company, now operating as Festool, produces portable power tools. Other important contributors to the modern chainsaw are Joseph Buford Cox and Andreas Stihl; the latter patented and developed an electric chainsaw for use on log bucking sites in 1926 and a gasoline-powered chainsaw in 1929, and founded a company to mass-produce them. In 1927, Emil Lerp, the founder of Dolmar, developed the world's first gasoline-powered chainsaw and mass-produced them. World War II interrupted the supply of German chainsaws to North America, so new manufacturers sprang up, including Industrial Engineering Ltd (IEL) in 1939, the forerunner of Pioneer Saws Ltd and part of Outboard Marine Corporation, the oldest manufacturer of chainsaws in North America. The first one-man chainsaw was introduced in 1950, though it was relatively heavy.
The World's Water Data Page FAO Comprehensive Water Database, AQUASTAT The Water Conflict Chronology: Water Conflict Database Archived 16 January 2013 at the Wayback Machine Water science school (USGS) Portal to The World Bank's strategy, work and associated publications on water resources America Water Resources Association Archived 24 March 2018 at the Wayback Machine Water on the web Water structure and science Archived 28 December 2014 at the Wayback Machine "Why water is one of the weirdest things in the universe", Ideas, BBC, Video, 3:16 minutes, 2019 The chemistry of water Archived 19 June 2020 at the Wayback Machine (NSF special report) The International Association for the Properties of Water and Steam Archived 27 September 2022 at the Wayback Machine H2O: The Molecule That Made Us, a 2020 PBS documentary
=== Hyperinsulinemic euglycemic clamp === The gold standard for investigating and quantifying insulin resistance is the "hyperinsulinemic euglycemic clamp," so-called because it measures the amount of glucose necessary to compensate for an increased insulin level without causing hypoglycemia. It is a type of glucose clamp technique. The test is rarely performed in clinical care, but is used in medical research, for example, to assess the effects of different medications. The rate of glucose infusion commonly is referred to in diabetes literature as the GINF value. The procedure takes about two hours. Through a peripheral vein, insulin is infused at 10–120 mU per m2 per minute. In order to compensate for the insulin infusion, glucose 20% is infused to maintain blood sugar levels between 5 and 5.5 mmol/L. The rate of glucose infusion is determined by checking the blood sugar levels every five to ten minutes. The insulin sensitivity is determined by the rate of glucose infusion during the last thirty minutes of the test. If high levels (7.5 mg/min or higher) are needed, the patient is considered insulin-sensitive. Conversely, very low levels (4.0 mg/min or lower) indicate insulin resistance. Levels falling between 4.0 and 7.5 mg/min are not conclusive and suggest "impaired glucose tolerance," which is an early indication of insulin resistance. This fundamental technique can be greatly enhanced through the utilization of glucose tracers. Glucose can be labeled with either stable or radioactive atoms.
=== REM sleep behavior disorder === Melatonin is a safer alternative than clonazepam in the treatment of REM sleep behavior disorder – a condition associated with the synucleinopathies like Parkinson's disease and dementia with Lewy bodies. However, clonazepam may be more effective. In any case, the quality of evidence for both treatments is very low and it is unclear whether either is definitely effective.
Sources: en.wikipedia.org
The 2000s and 2010s saw significant development in industrial automation of molecules as well as the emergence of general synthesis systems that could synthesise a wide variety of molecules on-demand, whose operation Melanie Trobe and Martin D. Burke compared to that of a 3D printer.
=== Meperidine === Meperidine is a synthetic opiate, part of the arylpiperidine class. It is a strong μ-receptor agonist with 1/10th the potency of morphine. It has historically also been used to treat rigors, and has a half-life of three to four hours. It is hepatically metabolized to the active metabolites of normeperidine, normepiridinic acid, and medperidinic acid. Normeperidine may accumulate to toxic levels in patients with renal impairment with repeated doses, and can cause CNS excitation and seizures.
== Research == Remdesivir was originally created and developed by Gilead Sciences in 2009, to treat hepatitis C and respiratory syncytial virus (RSV). It did not work against hepatitis C or RSV, but was then repurposed and studied as a potential treatment for Ebola virus disease and Marburg virus infections. According to the Czech News Agency, this new line of research was carried out under the direction of scientist Tomáš Cihlář. A collaboration of researchers from the Centers for Disease Control and Prevention (CDC) and Gilead Sciences subsequently discovered that remdesivir had antiviral activity in vitro against multiple filoviruses, pneumoviruses, paramyxoviruses, and coronaviruses. Preclinical and clinical research and development was done in collaboration between Gilead Sciences and various US government agencies and academic institutions. During the mid-2010s, the Mintz Levin law firm prosecuted various patent applications for remdesivir on behalf of Gilead Sciences before the United States Patent and Trademark Office (USPTO). The USPTO granted two patents on remdesivir to Gilead Sciences on 9 April 2019: one for filoviruses, and one which covered both arenaviruses and coronaviruses.
Sources: en.wikipedia.org
It is a short synthetic peptide built from seven amino acids: methionine, glutamic acid, histidine, phenylalanine and three prolines. The sequence derives from the 4-10 fragment of adrenocorticotropic hormone with an added proline-glycine-proline tail. No plant or animal extract is involved; the material is produced by solid-phase peptide synthesis.
It was developed in the Soviet Union during the early 1980s by groups at the Institute of Molecular Genetics in Moscow. Russian approval for intranasal use followed, and it has been marketed there since. Western laboratories encountered it mainly through translated literature and, later, through online research-chemical trade.
It holds a Russian registration as a prescription nasal product but has no approval from the European Medicines Agency or the United States Food and Drug Administration. Buyers outside Russia usually receive material sold strictly for laboratory research. That distinction matters because research-grade and pharmaceutical-grade products carry different documentation and testing expectations.
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.