intranasal delivery comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Updated 2025-08-08. Numbers and descriptions here follow the published literature rather than marketing material.
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.
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.
常规纯度与身份确认依赖反相高效液相色谱，并辅以质谱测定分子量。氨基酸组成分析可用于验证序列构成，肽图分析则能进一步定位修饰或降解产物。杂质谱通常关注缺失序列肽、截短片段和氧化产物。不同方法的检出限并不相同，因此各实验室报告的纯度数值不宜直接横向比较。
多数实验室与市售的 Semax 以冻干粉形式提供。冻干粉通常建议保存在 -20 °C 或更低温度下，同时避免光照与反复升温。短期运输有时采用冷藏条件，但长期保存仍以冷冻为主。分包操作应尽量减少开盖次数，以降低吸湿和微生物污染的风险。开封后若未一次用完，建议在干燥环境中密封并尽快放回低温储存。
| 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 |
当时的短肽研究普遍关注能否穿越血脑屏障、在低剂量下产生中枢效应，Semax 属于这一路线。鼻内给药是其主要使用方式，俄语文献报道的适应症涵盖缺血性卒中、短暂性脑缺血发作、认知功能减退以及视神经病变。这些研究大多发表在当地期刊上，样本规模与终点设置同西方试验惯例存在差异，国际同行对其临床证据的强度看法不一。
各国监管态度分化明显。俄罗斯按处方药管理，部分东欧国家留有使用记录；欧盟与美国未批准其作为药物上市，市面流通品通常标注为研究用化学品。身份差异意味着标示含量、纯度与无菌性缺少统一核查。体育领域还牵涉反兴奋剂名录，跨境携带则受目的地药品法规约束。
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.
Routine characterization relies on reversed-phase high-performance liquid chromatography to establish purity and on mass spectrometry to confirm molecular identity. Electrospray ionization and matrix-assisted laser desorption ionization are both used for mass verification. Amino acid analysis and peptide mapping can detect sequence errors. Common impurities include truncated sequences, methionine sulfoxide formed by oxidation, and deamidated products. Chromatograms are usually recorded near 214 nm, where the peptide backbone absorbs, and purity is reported as the percentage area of the principal peak.
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.
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.
Circulation time for the peptide is short because peptidases cleave it readily. The Pro-Gly-Pro tail is thought to slow breakdown compared with the bare ACTH fragment, but the gain appears modest. Absorption after intranasal dosing is limited, and only a fraction of a dose is expected to reach the central nervous system. Laboratory concentrations therefore sit well above levels achieved systemically, a gap that complicates translation from bench findings to clinical claims.
== Music video == The shoot for the music video was released on YouTube on September 30 by Mike & Rocco (reality). The video was set to premiere on January 5, 2009 but leaked on December 31, 2008 and was officially released on January 1, 2009 via MTV Jams.
== Disadvantages == However, there are some concerns associated with DBS biosampling. These include challenges related to sample volume, analyte recovery, the hematocrit effect, sample homogeneity, and the characteristics of the filter paper used.
=== Similar species === It can easily be mistaken for a variety of other members of the genus Tricholoma, such as T. auratum, T. aestuans, T. intermedium, T. sejunctum, and T. sulphureum. Other similar species include Floccularia albolanaripes and F. luteovirens.
== See also == Deputy (legislator) Member of Congress Australia and New Zealand Association of Clerks-at-the-Table, an association with the aim of advancing the professional development of parliamentarians.
=== Cells === In the lymphatic system a lymph node is a secondary lymphoid organ. Lymph nodes contain lymphocytes, a type of white blood cell, and are primarily made up of B cells and T cells. B cells are mainly found in the outer cortex where they are clustered together as follicular B cells in lymphoid follicles, and T cells and dendritic cells are mainly found in the paracortex. There are fewer cells in the medulla than the cortex. The medulla contains plasma cells, as well as macrophages which are present within the medullary sinuses. In case of diseases like cancer, macrophages within the lymph nodes may play pro-cancerous role by deleting anticancer T cells e.g., PD-L1+ macrophages in lymph nodes, facilitated by anticancer vaccines, can directly delete CD8+ T cells via extrinsinc apoptotic signalling. As part of the reticular network, there are follicular dendritic cells in the B cell follicle and fibroblastic reticular cells in the T cell cortex. The reticular network provides structural support and a surface for adhesion of the dendritic cells, macrophages and lymphocytes. It also allows exchange of material with blood through the high endothelial venules and provides the growth and regulatory factors necessary for activation and maturation of immune cells.
Sources: en.wikipedia.org
=== Monofunctional C1-tetrahydrofolate synthase === This enzyme is encoded by MTHFD1L and reversibly interconverts ADP + phosphate + 10-formyltetrahydrofolate to ATP + formate + tetrahydrofolate (EC 6.3.4.3).
=== Generic names === Gonadorelin is the generic name of the drug and its INNTooltip International Nonproprietary Name, BANTooltip British Approved Name, and JANTooltip Japanese Accepted Name, while gonadorelina is its DCITTooltip Denominazione Comune Italiana and gonadoréline is its DCFTooltip Dénomination Commune Française. The diacetate salt is known as gonadorelin acetate and this is its USANTooltip United States Adopted Name, BANMTooltip British Approved Name, and JANTooltip Japanese Accepted Name, while the hydrochloride salt is known as gonadorelin hydrochloride and this is its USANTooltip United States Adopted Name and BANMTooltip British Approved Name.
=== Dual inspired bioadhesives === By combining the catechol chemistry in marine mussels which is responsible for their ability to form strong wet adhesions, and the dissipative matrix found in the mucus of land slugs a dual bio inspired hydrogel adhesive was created. A double-bioinspired hydrogel adhesive (DBHA) thus consists of an intertwined catechol modified peptide dendrimer (G3KPC) with an anionic carboxymethyl cellulose and cationic chitosan (CC), network through covalent and noncovalent cross-linkages. This hydrogel has self healing abbilities due to the nature of the schiff base reaction, Micheal addition, and multiple noncovalent cross linkages in the gel, which allows them to re-cross link together with ease.
=== Web services for cheminformatics === CRDD developed an open source platform which allows users to predict inhibitors against novel M. Tuberculosis drug targets and other important properties of drug molecules like ADMET. Following are list of few servers.
Sources: en.wikipedia.org
=== Certification === Several bodies independently certify the production of tea, such as Rainforest Alliance, Fairtrade, UTZ Certified, and Organic. From 2008 to 2016, sustainability standards-certified tea production experienced a compound annual growth rate of about 35%, accounting for at least 19% of overall tea production. In 2016, at least 1.15 million tonnes of sustainably certified tea was produced, valued at US$2 billion. Rainforest Alliance certified tea is sold by Unilever brands Lipton and PG Tips in Western Europe, Australia and the U.S. Fairtrade certified tea is sold by a large number of suppliers around the world. UTZ Certified tea is sold by Pickwick tea.
=== Endogenous sources === ROS are produced during the processes of respiration and photosynthesis in organelles such as mitochondria, peroxisomes and chloroplasts. During the respiration process the mitochondria convert energy for the cell into a usable form, adenosine triphosphate (ATP). The process of ATP production in the mitochondria, called oxidative phosphorylation, involves the transport of protons (hydrogen ions) across the inner mitochondrial membrane by means of the electron transport chain. In the electron transport chain, electrons are passed through a series of proteins via oxidation-reduction reactions, with each acceptor protein along the chain having a greater reduction potential than the previous. The last destination for an electron along this chain is an oxygen molecule. In normal conditions, the oxygen is reduced to produce water; however, in about 0.1–2% of electrons passing through the chain (this number derives from studies in isolated mitochondria, though the exact rate in live organisms is yet to be fully agreed upon), oxygen is instead prematurely and incompletely reduced to give the superoxide radical (•O−2), most well documented for Complex I and Complex III. Another source of ROS production in animal cells is the electron transfer reactions catalyzed by the mitochondrial P450 systems in steroidogenic tissues. These P450 systems are dependent on the transfer of electrons from NADPH to P450. During this process, some electrons "leak" and react with O2 producing superoxide.
===== Causes ===== The cause of "cocaine nose" can be traced to the chemical process that occurs when cocaine hydrochloride is insufflated (snorted). As cocaine is absorbed through the nasal mucosa, the remaining hydrochloride component forms a dilute hydrochloric acid. The short half-life of cocaine, combined with binge use, may expose the nasal tissues to this acidic environment more frequently, increasing the risk of irritation and damage.
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.
一般不建议常温长期保存。多数说明指向 -20 °C 冷冻避光。常温运输通常被视为短期可接受，但会加快降解风险。