Semax raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2026-08-01. Anything still debated is marked as such rather than presented as settled.
Purity assessment relies mainly on reversed-phase high-performance liquid chromatography, which separates the target heptapeptide from truncated sequences, deletion analogues, and oxidised forms. Mass spectrometry, usually coupled to liquid chromatography, confirms identity through the expected molecular ion and reveals modifications such as methionine sulfoxide formation. Amino acid analysis can verify composition, and tandem mass spectrometry supports sequence confirmation. Ultraviolet detection near 254 to 280 nanometres is convenient because the phenylalanine and histidine residues absorb in that region. Nuclear magnetic resonance is rarely used for routine release testing.
Common degradation pathways include oxidation of the methionine side chain, hydrolysis of the peptide backbone, and aggregation under unfavourable pH or concentration. Stability studies typically monitor the main peak by chromatography and report total related substances as a percentage. Because no official monograph exists, acceptance criteria vary between laboratories, and reported purity values are not directly comparable across suppliers. Analysts therefore document the method, column, and detection wavelength alongside each result, and open questions remain about how much biological activity the oxidised forms retain.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Typical analytical method | Reversed-phase HPLC with UV detection | Separates target peptide from truncated and oxidised forms |
| Identity confirmation | LC-MS or ESI-MS | Compares observed and calculated molecular ion |
| Primary degradation route | Methionine oxidation | Forms the sulfoxide; monitored as an early-eluting peak |
| Short-term storage | 2 to 8 degrees Celsius | Applies to working vials and reconstituted portions |
| Common synonyms | ACTH(4–10) analogue, MEHFPGP | Descriptive names used in laboratory catalogues |
The mechanisms attributed to semax are inferred from animal and cell studies rather than traced to one confirmed target. The most frequently cited pathway involves increased expression of brain-derived neurotrophic factor and nerve growth factor in hippocampal and cortical tissue. Some work points to engagement of melanocortin receptors, particularly MC4, which the parent ACTH fragment can activate. Effects on dopaminergic and serotonergic signalling have also been reported. No single account explains all observed results, and the relative weight of each pathway remains unsettled.
Published studies examine a fairly narrow set of endpoints. Rodent experiments commonly measure maze learning, infarct volume after induced ischemia, and tissue levels of neurotrophic factors. Clinical reports from Russian centres describe attention, memory and recovery scores in patients after stroke or transient ischemic attack. Most of those human studies are small and few have been repeated by independent groups. Outcome measures differ between studies, which limits direct comparison.
Semax is a synthetic heptapeptide whose sequence is Met-Glu-His-Phe-Pro-Gly-Pro. The first four residues correspond to the ACTH(4-10) fragment, while the terminal Pro-Gly-Pro extension was added to improve metabolic stability. Its molecular formula is C37H51N9O10S and its monoisotopic mass is approximately 813.9 Da. The compound is classified as a peptide research chemical and as a registered pharmaceutical product in Russia, but it does not hold marketing approval in the European Union or the United States. Naming conventions vary across supplier catalogs.
Development of the compound took place in the Soviet Union during the 1980s, largely through peptide research groups affiliated with the Shemyakin-Ovchinnikov Institute and Moscow State University. Investigators screened fragments of adrenocorticotropic hormone for activity on the central nervous system while attempting to separate cognitive effects from hormonal ones. The shortened sequence was selected because it retained behavioral activity in animal models without stimulating corticosteroid release. Early publications described the molecule as an ACTH(4-10) analog.
Published research on this peptide originates mainly from Russian laboratories, and the wider international literature is comparatively thin. Studies have used rodent models of stroke, hypoxia, and memory tasks, with a smaller number of human trials reported. Reported outcomes include changes in attention and memory measures, along with effects on neurotrophic factor expression in some experiments. Small sample sizes, inconsistent dosing protocols, and limited independent replication are widely noted limitations, so the strength of the clinical evidence remains an open question.
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.
Semax is a synthetic heptapeptide developed in the Soviet Union during the 1980s by researchers at the Institute of Molecular Genetics in Moscow. It was designed as a truncated analog of adrenocorticotropic hormone, retaining only the fragment spanning residues four through ten. Investigators sought a peptide that would preserve the cognitive effects associated with ACTH while eliminating the hormonal stimulation of the adrenal cortex. The compound entered clinical use in Russia during the following decade.
Russian regulatory authorities approved the peptide for nasal administration, and it remains listed in the national pharmacopoeia under several trade names. Documented indications include acute ischemic stroke, transient ischemic attacks, traumatic brain injury, and certain ophthalmological and neurological conditions. Physicians also prescribe it for cognitive complaints in older patients, although the evidence base for that use is thinner. Outside Russia and a few neighboring states, the substance is not an approved medicine and is sold instead as a research chemical.
Later generations of the molecule include an N-acetylated form and an amidated form, both marketed online alongside the parent peptide. These variants differ in terminal chemistry and stability, and they are frequently discussed in the same breath even though they have not been compared in controlled trials. Supply outside formal healthcare systems comes largely from laboratories that synthesize peptides to order. Purity and identity of these materials vary widely, and no single body oversees the international trade.
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Imino acids are structurally related to amino acids, which have amino group instead of imine—a difference of single vs double-bond between nitrogen and carbon. The simplest example is dehydroglycine. D-Amino acid oxidase is an enzyme that is able to convert amino acids into imino acids. Also the direct biosynthetic precursor to the amino acid proline is the imino acid (S)-Δ1-pyrroline-5-carboxylate (P5C).
However, the "absolute zero" on the Kelvin temperature scale was originally defined in terms of the second law of thermodynamics, which Thomson himself described in 1852. Thomson did not assume that this was equal to the "zero-volume point" of Charles's law, merely said that Charles's law provided the minimum temperature which could be attained. The two can be shown to be equivalent by Ludwig Boltzmann's statistical view of entropy (1870). However, Charles also stated:
of the absorbing species is known. However, it is possible to overcome this difficulty and measure the temperature simultaneously. There are number of ways to measure the temperature. A widely applied method, which can measure the temperature simultaneously, uses the fact that the line strength
Sources: en.wikipedia.org
== Toxicity == Toxicity data in humans are limited, although laboratory studies indicate that certain compounds in the bark and roots or their extracts may cause adverse effects when consumed in excess. Supplementation with M. oleifera leaf extract is potentially toxic at levels exceeding 3,000 mg/kg of body weight, but safe at levels below 1,000 mg/kg. A study on albino mice found that high levels (>5,000mg/kg) of consumption could impair renal function. M. oleifera may interfere with prescription drugs affecting cytochrome P450 (including CYP3A4) and may inhibit the antihyperglycemic effect of sitagliptin. In November 2025, Food Standards Australia New Zealand (FSANZ) rejected an application to approve Moringa oleifera leaves, immature pods, and oil as a novel food. The decision cited insufficient evidence to confirm its safety for human consumption as a food. As a result (confirmed in May 2026 via Department of Agriculture notices), Moringa is not permitted as food or a food ingredient for retail sale in Australia.
== Characteristics == The leaves, known as tējapattā or tejpattā (तेजपत्ता) in Hindi, tejpāt (तेजपात/তেজপাত) in Nepali, Maithili, and Assamese, tejpātā (তেজপাতা) in Bengali, vazhanayila/edanayila (വഴനയില/എടനഇല) in Malayalam, kaḍu dhālchini (kn:ಕಾಡು ದಾಲ್ಚಿನ್ನಿ) in Kannada, tamalpatra (તમલપત્ર) in Gujarati, and tamālpatra (तमालपत्र) in Marathi and in original Sanskrit, are used extensively in the cuisines of India, Nepal, and Bhutan, particularly in the Mughlai cuisine of North India and Nepal and in tsheringma herbal tea in Bhutan. They are called biryāni āku/baghāra āku (బిర్యానీ ఆకు/బగార ఆకు) in Telugu and tejåpåtrå/tejåpåtårå (ତେଜପତ୍ର/ତେଜପତର) in Odia. The Lepcha of Sikkim call them naap saor koong.
Head of Change and Labs, Information and Digital Directorate, Foreign, Commonwealth and Development Office. For services to British Foreign Policy. Dr. Rosemary Joy Trevelyan. Director, The Tropical Biology Association. For services to Environmental Science and International Conservation. Pamela Vipond. Deputy Director, Olympic Solidarity, the International Olympic Committee. For services to Sport. Paul Walker. Co-Founder and Co-Director, Wildtracks, Belize. For services to Conservation and Biodiversity in Belize. Zoe Elizabeth Walker. Co-Founder and Co-Director, Wildtracks, Belize. For services to Conservation and Biodiversity in Belize. David Justin Warmback. Honorary Consul, Durban, South Africa. For services to British Nationals in South Africa. Christopher Michael Wicker. President and Trustee, Hertford British Hospital Charity; Secretary General, Save the Valletta Skyline Appeal. For services to Charity and to British Nationals in France and Malta. Steven Leonard Williams. Kyaninga Child Development Centre and Kyaninga Forest Foundation, Uganda. For services to Disabled Children and Local Communities in Western Uganda.
Sources: en.wikipedia.org
Dry powder is usually kept at about -20 degrees Celsius for long-term storage and at 2 to 8 degrees Celsius for short working periods. Containers should stay sealed and protected from light and moisture to limit degradation.
Oxidation of the methionine residue to the sulfoxide is a frequently reported change, and it usually appears as an earlier-eluting peak in reversed-phase chromatography. Backbone hydrolysis products can also accumulate in aqueous solution.
Liquid chromatography coupled with mass spectrometry is the usual approach, because the observed molecular ion can be compared with a calculated mass of about 813.9 Da. Retention time alone does not establish identity.
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.