The short version of intranasal delivery fits in a sentence. The long version — which is the one that helps — is below.
This page was last updated on 2025-11-04 and is reviewed periodically as new material appears.
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.
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.
纯度评估以反相高效液相色谱为主，通过主峰面积百分比给出粗略结果，再配合电喷雾质谱核对分子量。氨基酸分析可验证组成比例，手性色谱或毛细管电泳用于检查残基构型。常见杂质包括缺失序列的短肽、氧化产物与二聚体。由于多数市售品不附带完整检验报告，独立第三方检测常被用来核实标称值。
从分子层面看，Semax 是线性七肽，没有二硫键、糖基或脂链修饰，N 端为游离氨基，C 端为游离羧基。分子含组氨酸与谷氨酸侧链，因此在水和甲醇等极性溶剂中溶解良好，在非极性溶剂中溶解有限。计算分子量约为 814 Da，与其质子化离子的质荷比吻合，可用于质谱确认。
稳定性主要由水解与氧化两条路径支配。肽键在中性或弱酸性条件下相对稳定，遇到强碱或长时间高温则明显断裂；甲硫氨酸侧链容易被氧化成亚砜，使主峰前移并拉低实际含量。金属离子、光照和反复冻融会进一步促进降解或聚集。冻干粉在低温避光条件下可存放较长时间，配制后的水溶液通常需要冷藏并尽快用完。
| Property | Value | Notes |
|---|---|---|
| Chemical class | Synthetic heptapeptide | Analogue of the ACTH(4-10) fragment |
| Amino acid sequence | Met-Glu-His-Phe-Pro-Gly-Pro | Single-letter form MEHFPGP |
| Molecular formula | C37H51N9O10S | Free peptide, nominal mass near 814 Da |
| First registration | 1994, Russia | Nasal formulation for neurological indications |
| Typical purity grade | 95% or higher by HPLC | Research material; higher grades used as reference standards |
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.
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.
Proposed mechanisms center on neurotrophic signaling rather than on classical melanocortin receptor activation. Rodent experiments have reported shifts in the expression of brain-derived neurotrophic factor and nerve growth factor after administration, together with changes in the associated receptor systems. Several authors argue that the peptide acts largely through its degradation products and their interaction with peptidergic pathways, but this remains a hypothesis rather than a settled finding. No single molecular target has been identified in a way that the field broadly accepts.
Published research covers ischemic stroke, traumatic brain injury, cognitive impairment, optic nerve conditions and attention-related measures. Much of the human evidence comes from small trials conducted in one country, which limits how far the results generalize. Animal models supply the larger share of the data, and effects seen in rodents do not transfer automatically to people. Reviews have noted that methodological reporting is often incomplete, making it difficult to pool results or compare treatment schedules across studies.
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.
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.
Material sold for laboratory use varies widely in stated purity and documentation. A certificate of analysis should list the analytical method, the column and detector used, and the observed purity value. Independent verification by an outside laboratory is the practical way to confirm identity when documentation is absent or internally inconsistent. Regulatory status differs by country, and a product legal in one jurisdiction may be unapproved or controlled in another.
Identity and purity of semax are established with reversed-phase high-performance liquid chromatography coupled to ultraviolet detection, usually at 214 nanometres. Mass spectrometry, most often electrospray ionisation in positive mode, confirms the molecular mass and reveals truncated sequences. Amino acid analysis and peptide mapping after enzymatic digestion provide additional structural confirmation. Laboratories typically report purity as the percentage area of the main peak, a figure that does not capture isomeric or oxidised variants unless the method resolves them.
The peptide is prone to several degradation pathways. Oxidation of the methionine residue produces a sulfoxide that elutes close to the parent peak in many chromatographic systems. Hydrolysis of peptide bonds and deamidation of susceptible residues in related sequences also reduce purity over time. Lyophilised material kept dry at minus twenty degrees Celsius and shielded from light is the most stable form commonly described in laboratory practice.
Streptomycin is an antibiotic medication used to treat a number of bacterial infections, including tuberculosis, Mycobacterium avium complex, endocarditis, brucellosis, Burkholderia infection, plague, tularemia, and rat bite fever. For active tuberculosis it is often given together with isoniazid, rifampicin, and pyrazinamide. It is administered by injection into a vein or muscle. Common side effects include vertigo, vomiting, numbness of the face, fever, and rash. Use during pregnancy may result in permanent deafness in the developing baby. Use appears to be safe while breastfeeding. It is not recommended in people with myasthenia gravis or other neuromuscular disorders. Streptomycin is an aminoglycoside. It works by blocking the ability of 30S ribosomal subunits to make proteins, which results in bacterial death. Albert Schatz first isolated streptomycin in 1943 from Streptomyces griseus. It is on the World Health Organization's List of Essential Medicines. The World Health Organization classifies it as critically important for human medicine.
Dubnium is a synthetic chemical element; it has symbol Db and atomic number 105. It is highly radioactive: the most stable known isotope, dubnium-268, has a half-life of about 16 hours. This greatly limits extended research on the element. Dubnium does not occur naturally on Earth and is produced artificially. The Soviet Joint Institute for Nuclear Research (JINR) claimed the first discovery of the element in 1968, followed by the American Lawrence Berkeley Laboratory in 1970. Both teams proposed their names for the new element and used them without formal approval. The long-standing dispute was resolved in 1993 by an official investigation of the discovery claims by the Transfermium Working Group, formed by the International Union of Pure and Applied Chemistry and the International Union of Pure and Applied Physics, resulting in credit for the discovery being officially shared between both teams. The element was formally named dubnium in 1997 after the town of Dubna, the site of the JINR. Theoretical research establishes dubnium as a member of group 5 in the 6d series of transition metals, placing it under vanadium, niobium, and tantalum. Dubnium should share most properties, such as its valence electron configuration and having a dominant +5 oxidation state, with the other group 5 elements, with a few anomalies due to relativistic effects. A limited investigation of dubnium chemistry has confirmed this.
Myxosortases, homologs of the type 2 CAAX prenyl protease Rce1, are analogous protein-sorting enzymes, but they are unlikely to function as transpeptidases. It is likely, instead, that the cysteine residue in the target sequence is modified by a separate enzyme, and that modification is followed by cleavage by the myxosortase, as happens with Rce1. The exact biochemistry of the overall modification is not yet known.
Once the columns are filled with stationary phase, the mobile phase is pumped through, not continuously but, in pulses. The solvent motion created by a pulsed pumping action creates the mixing and settling that is common to most all forms of countercurrent chromatography.
=== Australia === The conservative Liberal–National Coalition issued a statement welcoming the news, with leader Sussan Ley remarking that "We should live in a world where dictators and despots face justice for their crimes." The Greens defense spokesman David Shoebridge condemned the operation as a breach of international law that "continues the world on a dangerous path of lawless aggression." Labor Against War, a political group within the ruling Labor Party, called on the government to condemn the strikes and to "immediately distance itself from the Trump administration, whose conduct is marked by [...] lawlessness at home and violent, reckless coercion abroad".
Sources: en.wikipedia.org
=== Asia === Drugs in Asia traditionally traveled the southern routes – the main caravan axes of Southeast Asia and Southern China – and include the former opium-producing countries of Thailand, Iran, and Pakistan. After the 1990s, particularly after the end of the Cold War (1991), borders were opened and trading and customs agreements were signed so that the routes expanded to include China, Central Asia, and Russia. There are, therefore, diversified drug trafficking routes available today, particularly in the heroin trade and these thrive due to the continuous development of new markets. A large amount of drugs are smuggled into Europe from Asia. The main sources of these drugs are Afghanistan, along with countries that constituted the so-called Golden Crescent. From these producers, drugs are smuggled into the West and Central Asia to its destinations in Europe and the United States. Iran is now a common route for smugglers, having been previously a primary trading route, due to its large-scale and costly war against drug trafficking. The Border Police Chief of Iran said that his country "is a strong barrier against the trafficking of illegal drugs to Caucasus, especially the Republic of Azerbaijan." The drugs produced by the Golden Triangle of Myanmar, Laos, and Thailand, on the other hand, pass through the southern routes to feed the Australian, US, and Asian markets.
=== Protein cages === The term protein cage delineates a diverse range of protein structures that are formed by the self-assembly of protein subunits into hollow macromolecular nanoparticles. These protein cages are nanoparticles that have one or more cavities present in their structure. The size of the cavity contributes to the size of the particle that the cavity can enclose, for example inorganic nanoparticles, nucleic acids, and even other proteins. The interior or chamber portion of the protein cage is usually accessible through a pore which is located in between protein subunits. The RNA exosome has nuclease active sites that are present in a cavity where 3' RNA degradation takes place; access to this cavity is controlled by a pore and this serves to prevent uncontrollable RNA decay. Some protein cages are dynamic structures that assemble and disassemble in response to external stimuli. Other examples of protein cages are clathrin cages, viral envelopes, chaperonins, and the iron storage protein ferritin.
Amitriptyline/chlordiazepoxide, sold under the brand names Limbitrol and Limbitrol DS, is a combination of amitriptyline (Elavil), a tricyclic antidepressant, and chlordiazepoxide (Librium), a benzodiazepine, which is approved for the treatment of depression associated with anxiety in the United States. It is taken orally and contains 12.5 to 25 mg amitriptyline and 5 to 10 mg chlordiazepoxide per tablet.
=== Presence in ecstasy === In his 1993 book E for Ecstasy examining the uses of the street drug ecstasy in the United Kingdom, the writer, activist, and ecstasy advocate Nicholas Saunders highlighted test results showing that certain consignments of the drug also contained selegiline. Consignments of ecstasy known as "Strawberry" contained what Saunders described as a "potentially dangerous combination of ketamine, ephedrine and selegiline," as did a consignment of "Sitting Duck" Ecstasy tablets.
Sources: en.wikipedia.org
Ornithine is a non-proteinogenic α-amino acid that plays an essential role in the urea cycle (to the extent that it is sometimes also called the Ornithine Cycle). Improper levels can cause disorders of the urea cycle, such as hyperornithinemia, hyperammonemia as well as other metabolic diseases such as gyrate atrophy and cancer. The name "ornithine" originates from the Greek word for bird (ornis or ornith-) in reference to its discovery as a benzoate ester in chicken excrement, by Max Jaffe in 1877. It is a key substrate for the biosynthesis of proline, polyamines and citrulline, but as a non-essential amino acid it is not incorporated into proteins in humans. The moiety derived from ornithine is called ornithyl.
== Characteristics == The gene encoding Braun's lipoprotein initially produces a protein composed of 78 amino acids, which includes a 20 amino acid signal peptide at the amino terminus. The mature protein is 6 kDa in size. Three monomers of Lpp assemble into a leucine zipper coiled-coil trimer. Large amounts of Braun's lipoprotein is present, more than any other protein in E. coli. Unlike other lipoproteins, it is linked covalently to the peptidoglycan. Lpp connects the outer membrane to the peptidoglycan. Lpp is anchored to the outer membrane by its amino-terminal lipid group. In E. coli, one third of Lpp proteins form a peptide bond via the side chain of its carboxy-terminal lysine with diaminopimelic acid in the peptidoglycan layer. The rest of the Lpp molecules are present in a "free" form unlinked to peptidoglycan. The free form is exposed on the surface of E. coli.
=== Lung transplant === Bronchiolitis obliterans is a common complication in lung transplants because transplanted lungs are at greater risk of alloimmunization as compared to healthy lungs. The disease is often termed bronchiolitis obliterans syndrome (BOS) in the setting of post lung transplantation and hematopoietic stem cell transplant (HSCT). Patients who develop BOS post lung transplant vary in disease latency and severity. Patients often initially have normal lung function on pulmonary function testing and have normal chest radiographs. As the disease progresses they begin to have symptoms of shortness of breath, cough, and wheezing as their lung function declines. The Journal of Heart and Lung Transplantation published updated guidelines in 2001 for grading the severity of BOS. The original guidelines and classification system were published in 1993 by the International Society for Heart and Lung Transplantation. Their scoring system is based on the changes in FEV1 in patients from their baseline. When patients are first diagnosed with BOS they have their baseline lung function established by doing pulmonary function testing at the time of diagnosis. The BOS scoring system is as follows: BOS 0: FEV1 > 90% of baseline and FEF25-75 > 75% of baseline BOS 0-p: FEV1 81-89% of baseline and/or FEF25-75 <= 75% of baseline BOS 1: FEV1 66-80% of baseline BOS 2: FEV1 51-65% of baseline BOS 3: FEV1 50% or less of baseline The scoring system shows an increased severity of the disease as the BOS number increases.
Sources: en.wikipedia.org
Registered medical products are most often 0.1% nasal drops. Research suppliers ship lyophilized powder, usually in milligram quantities, which is dissolved before use. The active peptide is the same in both cases; presentation and excipients differ.
No. The peptide is synthetic, although it is modelled on a fragment of a naturally occurring hormone. ACTH(4-10) is generated when ACTH is cleaved, but the Pro-Gly-Pro extension is not a known endogenous sequence. It is therefore a designed analogue rather than a natural metabolite.
The label reflects reported effects on attention, memory and recovery after neurological injury in regional clinical reports. Those reports are mostly small and have not been widely replicated outside the region. The classification is descriptive and does not imply a single defined mechanism.
电喷雾或基质辅助激光解吸电离质谱是常用手段，测得的质子化离子质荷比可换算为分子量。结果与理论值落在合理误差内，才支持结构一致的判断。