If you have been reading about heptapeptide 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 2026-07-20. 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.
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.
== Function == Dermcidin is a secreted protein that is subsequently processed into mature peptides of distinct biological activities. The C-terminal peptide is constitutively expressed in sweat and has antibacterial and antifungal activities. The N-terminal peptide, also known as diffusible survival evasion peptide, promotes neural cell survival under conditions of severe oxidative stress. A glycosylated form of the N-terminal peptide may be associated with cachexia (muscle wasting) in cancer patients.
A standardised set of terminology is used in anatomy to describe relative and absolute location and movement of anatomical parts. The standard anatomical position is the orientation that anatomical terms of location and motion are typically used in reference to. In humans, this refers to the body in a standing position with arms at the side and palms facing forward. Other positions referenced in medicine include prone (lying facing down) and supine (lying facing up).
== Usage and consumption == Chocolate is sold in chocolate bars, which come in dark chocolate, milk chocolate and white chocolate varieties. Some bars that are mostly chocolate have other ingredients blended into the chocolate, such as nuts, raisins, or crisped rice. Chocolate is used as an ingredient in a huge variety of bars, which typically contain various confectionary ingredients (e.g., nougat, wafers, caramel, nuts) which are coated in chocolate.
In practice, existing TA units found themselves stripped of regular training staffs and often many of their own officers and NCOs to form and train the new units, long before their own units were fully trained. As a result, some TA divisions had made little progress by the time the Second World War began; others, who had started from a stronger position, were able to complete this work within a matter of weeks.
Sources: en.wikipedia.org
Church records of christenings, marriages and burials Voter or citizenship rolls Records of wills and deceased estates Land tenure records Tax lists Muster lists for militia service The internet has stimulated amateur one-place studies, especially in England, since websites allow large volumes of historic material to be published easily. One-place studies of urban parishes are less common, since urban populations were migratory and analysis is more difficult when few of the families remain present for the whole period under study.
Thy-1 or CD90 (Cluster of Differentiation 90) is a 25–37 kDa heavily N-glycosylated, glycophosphatidylinositol (GPI) anchored conserved cell surface protein with a single V-like immunoglobulin domain, originally discovered as a thymocyte antigen. Thy-1 can be used as a marker for a variety of stem cells and for the axonal processes of mature neurons. Structural study of Thy-1 led to the foundation of the Immunoglobulin superfamily, of which it is the smallest member, and led to some of the initial biochemical description and characterization of a vertebrate GPI anchor and also the first demonstration of tissue specific differential glycosylation.
=== Phase 3 === Benzoyl peroxide/tretinoin (IDP-120) – combination of benzoyl peroxide (undefined mechanism of action) and tretinoin (retinoid) Berdazimer sodium (SB-204; MAP3-NONOate; NVN1000) – nitric oxide releasing agent Denifanstat (ASC–40; TVB-2640) – fatty acid synthetase complex inhibitor GED 0507-34-Levo (GED-0507; GED-0507-34; N-acetyl-GED-0507-34; NAC-GED-0507) – peroxisome proliferator-activated receptor gamma (PPARγ) modulator
=== Dosimetry === The radiation absorbed dose is the amount energy absorbed per unit weight of the target material. Dose is used because, when the same substance is given the same dose, similar changes are observed in the target material(Gy or J/kg). Dosimeters are used to measure dose, and are small components that, when exposed to ionizing radiation, change measurable physical attributes to a degree that can be correlated to the dose received. Measuring dose (dosimetry) involves exposing one or more dosimeters along with the target material. For purposes of legislation doses are divided into low (up to 1 kGy), medium (1 kGy to 10 kGy), and high-dose applications (above 10 kGy). High-dose applications are above those currently permitted in the US for commercial food items by the FDA and other regulators around the world, though these doses are approved for non commercial applications, such as sterilizing frozen meat for NASA astronauts (doses of 44 kGy) and food for hospital patients. The ratio of the maximum dose permitted at the outer edge (Dmax) to the minimum limit to achieve processing conditions (Dmin) determines the uniformity of dose distribution. This ratio determines how uniform the irradiation process is.
where the initial state is the acid solution with no Ca2+ (not taking into account possible CO2 dissolution) and the final state is the solution with saturated Ca2+. For strong acid concentrations, all species have a negligible concentration in the final state with respect to Ca2+ and A− so that the neutrality equation reduces approximately to 2[Ca2+] = [A−] yielding [Ca2+] ≈ 0.5 [A−]. When the concentration decreases, [HCO−3] becomes non-negligible so that the preceding expression is no longer valid. For vanishing acid concentrations, one can recover the final pH and the solubility of CaCO3 in pure water. In the case of a weak monoacid (here we take acetic acid with pKa = 4.76) with decreasing total acid concentration [A] = [A−] + [AH], we obtain:
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.