aliquot is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Last reviewed on 2026-02-03. Where a claim depends on a specific study, the study is described rather than over-claimed.
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。
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.
| Property | Value | Notes |
|---|---|---|
| 外观 | 白色至类白色粉末 | 常见于冻干制剂 |
| 溶解度 | 易溶于水 | 在极性溶剂中一般也可溶 |
| 建议储存温度 | -20 °C | 冻干粉，避光密封 |
| 常见分析手段 | 反相高效液相色谱 | 常与质谱联用 |
| 主要降解路径 | 水解与氧化 | 溶液状态更显著 |
Solid material is normally kept at minus 20 degrees Celsius in a sealed, desiccated container. Reconstituted solutions are less stable and are usually divided into single-use aliquots before freezing. Repeated freeze-thaw cycles are avoided because they promote aggregation and loss of activity. Light exposure is minimized by using amber glassware or foil wrapping. Published stability data for this peptide are sparse, so recommended storage conditions rest mainly on general practice for short synthetic peptides rather than on dedicated study.
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.
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.
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.
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.
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.
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.
=== Role in the immune system === Because the epithelium is often under external stress and is somewhat delicate, the lamina propria hosts many immune cells. In the intestinal tract the immune system must have tolerance to the normal intestinal flora, yet respond to pathogenic microorganisms. Imbalance of this causes inflammation diseases such as inflammatory bowel disease. The lamina propria’s richness in macrophages and lymphoid cells makes it a key place for immune responses to occur. It forms part of the barrier that protects internal tissues from external pathogenic microorganisms, especially from the gastrointestinal tract.
It is thought that in developed countries, the wealthy are able to afford more nutritious food, they are under greater social pressure to remain slim, and have more opportunities along with greater expectations for physical fitness. In undeveloped countries the ability to afford food, high energy expenditure with physical labor, and cultural values favoring a larger body size are believed to contribute to the observed patterns. Attitudes toward body weight held by people in one's life may also play a role in obesity. A correlation in BMI changes over time has been found among friends, siblings, and spouses. Stress and perceived low social status appear to increase risk of obesity. Smoking has a significant effect on an individual's weight. Those who quit smoking gain an average of 4.4 kilograms (9.7 lb) for men and 5.0 kilograms (11.0 lb) for women over ten years. However, changing rates of smoking have had little effect on the overall rates of obesity. In the United States, the number of children a person has is related to their risk of obesity. A woman's risk increases by 7% per child, while a man's risk increases by 4% per child. This could be partly explained by the fact that having dependent children decreases physical activity in Western parents. In the developing world urbanization is playing a role in increasing rate of obesity. In China overall rates of obesity are below 5%; however, in some cities rates of obesity are greater than 20%. In part, this may be because of urban design issues (such as inadequate public spaces for physical activity).
=== Gastrointestinal === Isotretinoin may cause non-specific gastrointestinal symptoms including nausea, diarrhea, and abdominal pain. The drug is associated with inflammatory bowel disease (IBD)—ulcerative colitis, but not Crohn's disease. There are also reports of people developing irritable bowel syndrome (IBS) and worsening of existing IBS.
== Routes of administration == Buccal Mucosa (inner cheek): Suitable for buccal administration. Labial Mucosa (inner lips): Suitable for buccal drug administration. Sublingual Mucosa (under tongue): Ideal for sublingual administration due to high permeability. Sublabial Mucosa (under lower lip): Suitable for sublabial administration due to good vascularization.
Sources: en.wikipedia.org
== History == 1979-1988: Research scientist and Senior research scientist of First Institute of Biochemistry, Semmelweis University Medical School and Hungarian Academy of Sciences 1988-1994: Head of Peptide Research Laboratory, Associate Professor of Biochemistry, Joint Research Organization of the Hungarian Academy of Sciences and Semmelweis University Medical School, The First Institute of Biochemistry 1994-2008: Head of Peptide Biochemistry Research Group and Rational Drug Design Laboratory, Professor of Biochemistry, Department of Medicinal Chemistry, Semmelweis Medical University 1992-1999: Scientific advisor of Sugen 1999-2005: Scientific advisor of Axxima Pharmaceuticals 1999–present: CEO and CSO of Vichem Chemie Research Ltd. 2001-2012: Chairman of Rational Drug Design Laboratories Co-operation Research Center, Semmelweis University 2002-2008: Curator of Office for Subsidised Research Units of Hungarian Academy of Sciences 2008-2012: Head of Signal Transduction Therapy Laboratory at Semmelweis University 2012–present: Head of Pathobiochemistry Research Group of Hungarian Academy of Sciences at Semmelweis University, Department of Medical Chemistry
Use of juice of Mikania as a curative agent for itches is reported from Malaysia. However, in all such cases, therapeutic evidence are scarce or lacking. In Africa, Mikania leaves are used as a vegetable for making soups. The weed is used as a cover crop in rubber plantations in Malaysia. It is also planted on slopes to prevent soil erosion. Mikania green manure has been reported to increase the yield of rice in Mizoram, India. Recent studies have shown that Mikania is not suitable for mulching and composting due to its high water content.
== Other research == In October 2021, Relief announced that its collaboration partner, Texas-based Acer Therapeutics, had successfully filed for a New Drug Application with US FDA for their drug ACER-001, for the treatment of Urea Cycle Disorders (UCDs) and Maple syrup urine disease. In September 2021, APR launched a chewable tablet for the treatment of Phenylketonuria, called PKU GOLIKE KRUNCH, in Germany and Italy. APR are also developing Nexodyn, a drug which aids in the management of hard-to-heal ulcers requiring long periods of treatment. Relief is actively developing RLF-100 for non-COVID-19 related acute and chronic lung diseases, such as Pulmonary sarcoidosis.
Sources: en.wikipedia.org
=== GLC (1981–1985) === The equivalent American Mazda GLC (Great Little Car) appeared in the 1981 model year, although the rear-wheel drive wagon also continued to be offered. It was only offered with a single engine – the twin-barrel 1.5-litre with 68 hp (51 kW)—and lasted through 1985, after which it was replaced by the next-generation Mazda 323. With this, the GLC nameplate was retired. The BD was the only front-wheel drive Mazda vehicle using the GLC name. Originally it was offered with three- or five-door bodywork, in standard, Custom, Custom L, or Sport equipment levels. The five-door only came as a Custom and was sold only in Hawaii and Puerto Rico. All cars received exposed rectangular sealed-beam units. The later four-door saloon, introduced for 1983, was available in Custom, Custom L, and Sport models. The Sport received blacked out trim, a steering wheel borrowed from the RX-7, full instrumentation, and a special rear interior which closely integrates the side trim with the rear seat design – an early iteration of a design philosophy taken to its extreme with the 1988 Persona and the 1990 Eunos Cosmo. Unlike the sporting 323s in other markets, the Sport only received special hubcaps, rather than alloy wheels. For 1982, the Sport was made to live up to its name a little bit more, with the installation of a front anti-roll bar and cast aluminum wheels. The five-door GLC gained a fully carpeted trunk for 1982.
== Development and applications == nanoCLAMPs were developed in the laboratories of Nectagen. nanoCLAMP phage display libraries were constructed that contained variations on 16 surface amino acids in three loops with function diversities of approximately 109 variants. These libraries have been screened for binders to target proteins and peptides, typically yielding between 1 and 30 unique binders to the target. Purified nanoCLAMPs containing a single C-terminal cysteine can be easily conjugated to halo-acetyl activated agarose resins under native or denaturing conditions, and the resulting thioether bond renders the resins leach-proof. Targets can be purified to apparent homogeneity in a single-step. The polyol-responsive nature of the resins allows the targets to be eluted with 0.75 M ammonium sulfate and 40% propylene glycol at pH 7.9, conditions which have been shown to preserve native structure and protein complexes. nanoCLAMPs have been produced that target green fluorescent protein (GFP), mCherry, SUMO (SMT3), NusA, avidin, NeutrAvidin, maltose-binding protein (MBP), thioredoxin 1, beta-galactosidase, SlyD, and others. Typical binding capacities of resins range from 1 to 4 mg/ml resin. Because nanoCLAMPs readily refold, nanoCLAMP resins can be regenerated multiple times using guanidinium chloride to clean the resin.
10 Ca(OH)2 + 6 H3PO4 → Ca10(PO4)6(OH)2 + 18 H2O The ability to synthetically replicate hydroxyapatite has invaluable clinical implications, especially in dentistry. Each technique yields hydroxyapatite crystals of varied characteristics, such as size and shape. These variations have a marked effect on the biological and mechanical properties of the compound, and therefore these hydroxyapatite products have different clinical uses.
=== Utah === On March 13, 2024, Utah Governor Spencer Cox signed the Artificial Intelligence Policy Act (S.B 149). This legislation went into effect on May 1, 2024. It established liability, notably for companies that do not disclose their use of generative AI when required by state consumer protection laws, or when users commit criminal offense using generative AI. It also created the Office of Artificial Intelligence Policy and the Artificial Intelligence Learning Laboratory Program.
Sources: en.wikipedia.org
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。
公开资料对此没有统一答案。普遍建议现配现用，或冷藏并在数日内用完。含甲硫氨酸的序列更易氧化，放置时间越长风险越高。
反相高效液相色谱是最常用的手段，配合质谱确认分子量。氨基酸组成分析和肽图分析可补充序列层面的验证。
It originated at the Institute of Molecular Genetics in Moscow during the 1980s. The work was carried out by a Russian research group that specialized in peptide neuropharmacology.