If you have been reading about single-use aliquot 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.
Last reviewed on 2026-02-14. Where a claim depends on a specific study, the study is described rather than over-claimed.
Once dissolved, the peptide is considerably less stable than the solid. Aqueous solutions are usually prepared at neutral to slightly acidic pH, filtered, and divided into single-use aliquots before freezing. Repeated freeze-thaw cycles are a common cause of avoidable loss and are best prevented by never refreezing a thawed aliquot. Adsorption to plastic and glass surfaces can lower the measured concentration of dilute solutions, particularly below roughly 0.1 mg/mL. Buffer choice, salt content, and container material all influence how much peptide remains detectable after storage.
Identity and purity are established with standard peptide methods. Reversed-phase HPLC with ultraviolet detection near 214 nm resolves the parent peak from deletion and truncation byproducts, and reports typically quote a main-peak percentage. Mass spectrometry by electrospray or MALDI-TOF confirms the expected molecular mass, while amino acid analysis or peptide mapping can verify composition when the sequence itself is in question. A certificate of analysis that pairs a chromatogram with a mass spectrum is more informative than a purity figure alone. Counter-ion content and residual solvents are separate specifications and are frequently omitted.
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.
| Property | Value | Notes |
|---|---|---|
| Solid storage temperature | -20 °C or below | Desiccated and protected from light |
| Solution storage temperature | -80 °C as single-use aliquots | Avoid repeated freeze-thaw cycles |
| Purity assessment method | RP-HPLC, around 214 nm | Reported as main-peak area percent |
| Identity confirmation method | ESI-MS or MALDI-TOF | Measured mass compared with calculated mass |
| Common synonyms | ACTH(4-10) analog; Met-Glu-His-Phe-Pro-Gly-Pro | Also written as Semaxum in some sources |
溶液状态的稳定性明显低于冻干粉。肽类在水溶液中可能经历水解、氧化与聚集，其中甲硫氨酸和天冬酰胺等残基常是敏感位点。Semax 含有甲硫氨酸，因此氧化风险相对突出。工作液一般主张现配现用，或冷藏并在数日内用尽。缓冲液种类、pH 和离子强度都会影响降解速率，而关于最佳条件的公开数据并不统一。
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。
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.
Pharmacological accounts link semax to melanocortin signalling and to modulation of neurotrophic factor expression, particularly brain-derived neurotrophic factor and nerve growth factor. Much of this evidence comes from rodent studies using intranasal delivery, a route chosen because it allows peptides to reach the central nervous system with limited systemic exposure. Whether the same mechanisms operate in humans at comparable magnitude remains an open question. The precise receptor or receptors responsible for the reported behavioural and neuroprotective effects have not been conclusively identified.
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.
Verification of a supplied batch generally combines a certificate of analysis with independent testing, because certificates are self-reported documents. A typical package includes a chromatographic trace, a mass spectrum, and a stated water or counter-ion content. Batch-to-batch consistency matters more than a single purity figure when results are compared across experiments. No single mandatory standard governs research-grade peptide release, so laboratories are expected to define their own acceptance criteria. Residual trifluoroacetate from purification is a frequently overlooked counter-ion.
The new 5th district encompasses the southeastern parts of the Dallas–Fort Worth Metroplex, including Mesquite, Terrell, Palestine, Athens, Canton, Kaufman, the southern halves of Garland and Rowlett, and the Lakewood and Lake Highlands portions of Dallas. The incumbent is Republican Lance Gooden, who was re-elected with 64.1% of the vote in 2024. Donald Trump and Ted Cruz each respectively won 60.1% and 56.9% of the vote in this district in 2024.
=== Lawsuits === From 2019 to 2024, Maria Francesca Gioia, a former medical student acting as a pro se plaintiff, filed nine product liability lawsuits against Janssen Pharmaceuticals and related parties. She alleged that taking Invega Sustenna (paliperidone palmitate) caused her memory loss, hypothyroidism, Horner's syndrome, nerve damage, motor tremors, vocal tics, confusion, loss of taste and sensation, post-traumatic stress disorder, and metabolic syndrome (including hypertension, diabetes, and stroke), which ended her career as a primary care physician. All nine lawsuits were dismissed on procedural grounds: Gioia I–II for failure to state a claim, Gioia III for failure to prosecute, and Gioia IV–V for lack of subject matter jurisdiction. The court also noted that the side effects she alleged were already listed on Invega's FDA-approved warning label. In September 2024, Cassandra Fameux filed a criminal complaint alleging that her husband, a Michigan anesthesiologist, had forcibly injected her with unprescribed Invega Sustenna on multiple occasions between 2017 and 2021. A subsequent police investigation led to a recommendation that he be charged with domestic assault. In May and June 2022, Adilah Patton, a 28‑year‑old pretrial detainee in Indianapolis, was forcibly injected twice with unprescribed Invega Sustenna while in custody at the Marion County Adult Detention Center. A federal lawsuit filed on her behalf alleges that the injections were administered without a medical assessment, a prescription, or the consent of her court‑appointed guardian.
== Actions == Neurons communicate with each other through synapses, specialized contact points where neurotransmitters transmit signals. When an action potential reaches the presynaptic terminal, voltage-gated calcium channels open, allowing calcium ions to enter the terminal. This calcium influx triggers the fusion of synaptic vesicles with the presynaptic membrane, leading to the release of neurotransmitters into the synaptic cleft. These neurotransmitters then bind to receptors on the postsynaptic membrane, influencing the receiving neuron in either an inhibitory or excitatory manner. If the overall excitatory influences outweigh the inhibitory influences, the receiving neuron may generate its own action potential, continuing the transmission of information to the next neuron in the network. This process allows for the flow of information and the formation of complex neural networks.
Sources: en.wikipedia.org
Histatins are a family of histidine-rich (cationic) antimicrobial proteins found in saliva. Histatin's involvement in antimicrobial activities makes histatin part of the innate immune system. Histatin was first discovered (isolated) in 1988, with functions that are responsible in keeping homeostasis inside the oral cavity, helping in the formation of pellicles, and assist in bonding of metal ions. Histatin has multiple structures, dependent on the specific protein of interest.
=== Street Cricket === The Mid West Rhinos are embarking on another project to bring "Street Cricket" to the suburb of Mbizo. The project which was started by Sporting Chance aims to give young people an opportunity to play a simple version of cricket within their community. Street Cricket can be played with just a bat and ball and it is hoped that by operating this project, the young people will be able to learn new skills and will encourage them to take up the full version of the game. Sponsorship Whilst the funding of local cricket comes from Zimbabwe Cricket, there is still a requirement for sponsorship from external sources. The majority of funding for League cricket comes from the Cold Chain Group. The other sponsors include Lays, Bokomo, Castle and local sponsors such as Steel Makers, Cricket Tours Africa and Vinyl Stikka Signs.
== Function == The architecture of a dry shipper encompasses two primary components: an internal canister and an external protective shell. The inner canister, designed to hold biological specimens, is positioned within the vapor phase of the liquid nitrogen. This configuration ensures that the specimens are maintained at temperatures below -150 °C (302 °F) for prolonged periods. A distinctive feature of dry shippers is their ability to avert direct contact between samples and liquid nitrogen, reducing risks of contamination and ensuring consistent cryogenic conditions during transit.
...some of the actions adopted by those aiming to stop tours were despicable. Bette [Bill McLaren's wife] and I were referred to as 'racist scum' on our way down to Mansfield Park to see the South African Barbarians play in 1979 – a tour party comprising equal numbers of coloureds, blacks and whites. That, said the protesters, was just window dressing. When the Springboks last toured the UK, I was asked to provide commentary on their match against the Midland Counties (East) at Welford Road, Leicester. I remember having to walk the gauntlet up a narrow channel lined on each side by policemen holding back the mob. Those policemen were covered in spittle, had hats knocked off, were kicked in places where no man should be kicked, and yet took it all with stoic calm. I couldn't believe that people in the British Isles would behaved in that manner.... Constant noise outside the South Africans' hotels to try and prevent them sleeping was another unbelievable ploy that sickened decent people.
Sources: en.wikipedia.org
Each freeze-thaw cycle can degrade a fraction of the peptide and promote aggregation. Dividing a stock solution into single-use volumes removes repeated cycling as a variable. It also limits the time a thawed solution spends at room temperature.
A high main-peak percentage says little about identity, counter-ion content, or residual solvents. It also does not distinguish an isomer or a closely eluting analog. Mass confirmation and the accompanying documentation cover those gaps.
Salt form changes mass, solubility, and hygroscopicity, and acetate and trifluoroacetate salts behave differently in solution. Storage guidance still centers on -20 °C for powder and lower temperatures for solutions. The certificate should state which salt is present.
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.