The short version of reversed-phase HPLC fits in a sentence. The long version — which is the one that helps — is below.
This page was last updated on 2026-07-10 and is reviewed periodically as new material appears.
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.
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 supplied as a lyophilized powder that appears white to off-white. It dissolves readily in water, phosphate-buffered saline, and other aqueous media, which simplifies preparation of working solutions for laboratory use. The nasal products registered in Russia are dilute aqueous solutions, typically around 0.1 percent peptide by weight. Organic solvents are rarely necessary and can complicate handling. Because the peptide is hygroscopic, weighing should be performed quickly and with minimal exposure to ambient humidity.
| 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 |
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.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It is described in the literature as an analogue of the ACTH(4–10) fragment, a short N-terminal portion of adrenocorticotropic hormone that retains some neurotropic activity without the full hormonal effects of the parent peptide. The molecule carries a methionine residue at the N-terminus and two proline residues near the C-terminus, features that shape both its interactions with receptor systems and its chemical stability. The free peptide corresponds to the formula C37H51N9O10S and a molecular mass near 813.9 Da.
Claims about enhanced focus, memory, or mood in healthy people rest mostly on anecdotal reports and community discussion rather than on controlled data. It remains unclear whether any cognitive benefit observed in patients recovering from brain injury would extend to uninjured users. Dose-response relationships, long-term safety, and interactions with other drugs are not well characterized in the peer-reviewed literature. Questions about optimal route of administration and treatment duration likewise remain open.
Semax binds to melanocortin receptors and is thought to influence neuronal survival and plasticity rather than to act through the adrenal axis. Laboratory work has shown increased expression of brain-derived neurotrophic factor and nerve growth factor in treated tissue. Changes in c-Fos, a marker of neuronal activation, have also been reported. Because the peptide is rapidly degraded by peptidases, its effects are generally attributed to downstream signaling cascades rather than to sustained receptor occupancy.
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.
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.
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=== Final weeks on the Gulf Coast === Filming resumed on July 19. The sandpit fight scene between Bosworth and pro wrestler Tom Magee was shot in Bay St. Louis. It was aborted after a first attempt where Bosworth clipped Magee's cheek with a punch, and finished two weeks later on August 9. While a King Features gossip column claimed that the botch had led to a real scuffle, Bosworth himself assured that the accident had been handled in a civil manner by both. The final scene shot on the Gulf Coast was a gas station explosion on Daisy Vestry Road in Latimer on August 10.
Receptors of a particular type are linked to specific cellular biochemical pathways that correspond to the signal. While numerous receptors are found in most cells, each receptor will only bind with ligands of a particular structure. This has been analogously compared to how locks will only accept specifically shaped keys. When a ligand binds to a corresponding receptor, it activates or inhibits the receptor's associated biochemical pathway, which may also be highly specialised. Receptor proteins can be also classified by the property of the ligands. Such classifications include chemoreceptors, mechanoreceptors, gravitropic receptors, photoreceptors, magnetoreceptors and gasoreceptors.
The ABCB subfamily is composed of four full transporters and two half transporters. This is the only human subfamily to have both half and full types of transporters. ABCB1 was discovered as a protein overexpressed in certain drug resistant tumor cells. It is expressed primarily in the blood–brain barrier and liver and is thought to be involved in protecting cells from toxins. Cells that overexpress this protein exhibit multi-drug resistance.
Sources: en.wikipedia.org
== Role in cancer == Most germline or somatic mutations in the MEN1 gene predict truncation or absence of encoded menin resulting in the inability of MEN1 to act as a tumor suppressor gene. Such mutations in MEN1 have been associated with defective binding of encoded menin to proteins implicated in genetic and epigenetic mechanisms. Menin is a 621 amino acid protein associated with insulinomas which acts as an adapter while also interacting with partner proteins involved in vital cell activities such as transcriptional regulation, cell division, cell proliferation, and genome stability. Insulinomas are neuroendocrine tumors of the pancreas with an incidence of 0.4 % which usually are benign solitary tumors but 5-12 % of cases have distant metastasis at diagnosis. These familial MEN-1 and sporadic tumors may arise either due to loss of heterozygosity or the chromosome region 11q13 where MEN1 is located, or due to presence of mutations in the gene. MEN1 mutations comprise mostly frameshift deletions or insertions, followed by nonsense, missense, splice-site mutations and either part or complete gene deletions resulting in disease pathology. Frameshift and nonsense mutations result in a supposed inactive and truncated menin protein while splice-site mutations result in incorrectly spliced mRNA. Missense mutations of MEN1 are especially important as they result in a change to crucial amino acids needed in order to bind and interact with other proteins and molecules.
On 20 February 1990 the Volkskammer passed a new electoral law, reducing it in size to 400 members elected via party-list proportional representation, with no electoral threshold. Joint lists between parties were allowed, and a number of parties formed alliances for the election, including the Association of Free Democrats, Alliance 90, and an alliance between the Green Party and Independent Women's Association. Seats were calculated nationally using the largest remainder method, and distributed in multi-member constituencies corresponding to the fifteen Bezirke.
=== Biosynthetic pathway === The metabolic pathway to produce ergothioneine starts with the methylation of histidine to produce histidine betaine (hercynine). The sulfur atom is then incorporated from cysteine. The biosynthetic genes of ergothioneine have been described in detail for Mycobacterium smegmatis, Neurospora crassa, Schizosaccharomyces pombe (with homologues in Aspergillus, a genus important in food fermentation), and Caldithrix abyssi. This pathway has recently also been discovered in plants. Different groups of organisms use different approaches to sulfur-addition. Aerobic bacteria and fungi use an O2-dependent reaction that is catalyzed by a mononuclear non-heme iron enzyme, with cysteine or γ-glutamylcysteine as the sulfur source. Green sulfur bacteria and some archaea use a rhodanese-like sulfur transferase to perform oxidative polar substitution. Caldithrix uses a metallopterin-dependent bifunctional enzyme that combines an N-terminal domain similar to a tungsten-dependent acetylene hydratase and a C-terminal cysteine desulfurase domain. Homologs of the Caldithrix system are found in anaerobic bacteria and some archaea.
==== Interaction with the GTPase Associated Center ==== The GTPase Associated Center (GAC) is a region on the large ribosomal subunit that consists of two smaller regions of 23S ribosomal RNA called the L11 stalk and the sarcin-ricin loop (SRL). As a highly conserved rRNA loop in evolution, the SRL is critical in helping GTPases bind to the ribosome, but is not essential for GTP hydrolysis. There is some evidence to support that a phosphate oxygen in the A2662 residue of the SRL may help hydrolyze GTP.
Pyruvate dehydrogenase complex (PDC) is a complex of three enzymes that converts pyruvate into acetyl-CoA by a process called pyruvate decarboxylation. Acetyl-CoA may then be used in the citric acid cycle to carry out cellular respiration, and this complex links the glycolysis metabolic pathway to the citric acid cycle. Pyruvate decarboxylation is also known as the "pyruvate dehydrogenase reaction" because it also involves the oxidation of pyruvate. The levels of pyruvate dehydrogenase enzymes play a major role in regulating the rate of carbohydrate metabolism and are strongly stimulated by the evolutionarily ancient hormone insulin. The PDC is opposed by the activity of pyruvate dehydrogenase kinase, and this mechanism plays a pivotal role in regulating rates of carbohydrate and lipid metabolism in many physiological states across taxa, including feeding, starvation, diabetes mellitus, hyperthyroidism, and hibernation. The multienzyme complex is structurally and functionally related to the oxoglutarate dehydrogenase complex (OGDC), the 2-oxoadipate dehydrogenase complex (OADHC) and the branched-chain oxo-acid dehydrogenase complex (BCKDC), all of which are members of the 2-oxoacid dehydrogenase complex family. A role for insulin in the regulation of glucose homeostasis, pyruvate dehydrogenase levels, and the generation of AMP-activated protein kinase (AMPK) in the electron transport chain has been evolutionarily conserved across species.
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.
Solid peptide is best kept frozen at about minus 20 degrees Celsius in a sealed container with desiccant. It should be allowed to reach room temperature before opening to prevent condensation. Repeated warming and cooling of the same vial is discouraged.