The short version of aliquot fits in a sentence. The long version — which is the one that helps — is below.
Reviewed 2026-02-16. Anything still debated is marked as such rather than presented as settled.
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.
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.
Development took place during the 1980s at institutes of the Russian Academy of Sciences, where peptide fragments of ACTH were screened for cognitive and neuroprotective effects. The compound received regulatory approval in Russia as a nasal preparation, marketed for conditions such as ischemic stroke, transient ischemic attacks, and optic nerve disorders. Registration in other countries has not followed. Most published clinical reports originate from a small number of Russian research groups, and independent replication outside that setting remains limited. The regulatory status therefore differs sharply between Russia and the rest of the world.
Laboratory work points toward modulation of neurotrophic signaling, particularly expression of brain-derived neurotrophic factor and nerve growth factor in hippocampal tissue. Studies also describe effects on monoamine turnover, inflammatory mediators, and oxidative markers. These observations come mainly from animal models and cultured cells, so the causal chain in humans is not firmly established. Whether the reported molecular changes translate into measurable clinical benefit is an open question. Reviews generally present the mechanism as plausible rather than demonstrated.
Clinical evidence consists largely of small trials with modest sample sizes, often without independent replication. Reported endpoints include cognitive scores, recovery after stroke, and visual function, but study designs vary widely and few trials meet contemporary reporting standards. Systematic reviewers have noted a high risk of bias in several of these reports. No large multicenter trial conducted outside Russia has been published. The compound is therefore best described as investigational in most jurisdictions, with its clinical role still unresolved.
| Property | Value | Notes |
|---|---|---|
| Typical purity | ≥95% by HPLC | Research-grade material |
| Detection wavelength | 214 nm | Peptide bond absorbance |
| Reconstitution medium | Sterile water or saline | Prepare fresh or aliquot immediately |
| Storage (solution) | -80 °C, single-use aliquots | Avoid repeated freeze-thaw cycles |
| Common salt form | Acetate or trifluoroacetate | Affects mass and solubility |
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.
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.
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.
Milk ejection reflex/Letdown reflex: in lactating (breastfeeding) mothers, oxytocin acts at the mammary glands, causing milk to be 'let down' into lactiferous ducts, from where it can be excreted via the nipple. Suckling by the infant at the nipple is relayed by spinal nerves to the hypothalamus. The stimulation causes neurons that produce oxytocin to fire action potentials in intermittent bursts; these bursts result in oxytocin pulses from the neurosecretory nerve terminals of the pituitary gland. Uterine contraction: important for cervical dilation before birth, oxytocin causes contractions during the second and third stages of labor. Oxytocin release during breastfeeding causes mild but often painful contractions during the first few weeks of lactation. This also assists the uterus in clotting the placental attachment point postpartum. However, in knockout mice lacking the oxytocin receptor, reproductive behavior and birth are normal. In male rats, oxytocin may induce erections. A burst of oxytocin is released during ejaculation in several species, including human males; its suggested function is to stimulate contractions of the reproductive tract, aiding sperm release. Human sexual response: Oxytocin levels in plasma rise during sexual stimulation and orgasm. At least two uncontrolled studies have found increases in plasma oxytocin at orgasm in both men and women. Plasma oxytocin levels are increased around the time of self-stimulated orgasm and are still higher than baseline when measured five minutes after self arousal.
In some jurisdictions, designer drugs may fall under analog acts which impose restrictions upon substances which are substantially chemically or pharmacologically similar to existing controlled substances.
The first floral wire service, established by a group of 15 US florists in 1910, was Florists' Telegraph Delivery Service (FTD). The group was formed as a cooperative and was mutually owned by its members. Members exchanged orders via telegraph messages and hence the name 'wire service' was used to identify the order exchange business model. In 1965, with the introduction of international order sending, FTD changed its name to Florists' Transworld Delivery. In the 1920s, a group of British florists formed a similar 'Flowers by Wire' group. This group, also a business cooperative and affiliated with FTD, began operating under the name Interflora in 1953. By the 1970s, most European countries had their own Interflora units. In addition to the cooperatives, independently owned and operated for-profit companies built their own proprietary networks including Teleflora and 1-800-Flowers with their BloomNet division.
=== Monolayer sheets === In 2013 a group of Polish scientists presented a production unit that allows the manufacture of continuous monolayer sheets. The process is based on graphene growth on a liquid metal matrix. The product of this process was called High Strength Metallurgical Graphene. In a new study published in Nature, the researchers have used a single-layer graphene electrode and a novel surface-sensitive non-linear spectroscopy technique to investigate the top-most water layer at the electrochemically charged surface. They found that the interfacial water response to the applied electric field is asymmetric concerning the nature of the applied field.
Autoimmune disorder, such as systemic lupus erythematosus (SLE), rheumatoid arthritis, and Sjögren's syndrome Chronic liver disease, such as cirrhosis Certain medications, including thiazide diuretics and opiates Genetic factors: There may be a genetic component
Sources: en.wikipedia.org
=== Ion funnel === Ion funnels are RF devices which have been used for decades to focus ion currents into narrow beams. In PTR-MS they have been introduced in 2012 by Barber et al. when they presented a PTR-MS setup with a PTR reaction region incorporating an ion funnel. Although the focusing properties of the ion funnel improved the sensitivity of the setup by a factor of >200 (compared to operating in DC only mode, i.e. with the ion funnel turned off) for some compounds, the sensitivities of other compounds were only improved by a factor of <10. That is, because of the highly compound dependent instrumental response one of the main advantages of PTR-MS, namely that concentration values can be directly calculated, is lost and a calibration measurement is needed for each analyte of interest. Furthermore, with this approach unusual fragmentation of analytes has been observed which complicates interpretation of measurement results and comparison between different types of instruments even more. A different concept has been introduced by the company IONICON Analytik GmbH. (Innsbruck, AT) where the ion funnel is not predominantly part of the reaction region but mainly for focusing the ions into the transfer region to the TOF mass spectrometer. In combination with the above-mentioned method of controlling the ion chemistry this enables a considerable increase in sensitivity and thus also an improvement of the detection limit, while keeping the ion chemistry well-defined and thus avoiding problems with quantification and interpretation of the results.
== History == On 28 November 2016, the university came into existence via Haryana Vidhan Sabha legislature. On 18 April 2017, Chief Minister Manohar Lal Khattar's administration renamed it after the Maharana Pratap.
From then, Alicent's party was known as the "greens" and Rhaenyra's supporters were labeled the "blacks". At the great ceremonial tourney on that day, Viserys and Daemon reunited after several years apart, as Daemon handed Viserys his crown from the Stepstones. The reunion lasted only for six months, as Viserys exiled Daemon once again for reasons unclear, though Septon Eustace claims that Daemon had seduced Rhaenyra and took her maidenhead. Viserys attempted to stabilize relations between the blacks and greens through various gatherings and respective apologies to each other, asserting that he loved Rhaenyra and Alicent equally. In 113 AC, Viserys attempted to find a betrothal for Rhaenyra, believing that the time was right for her to marry. Following the advice of his council, Viserys betrothed her to Laenor Velaryon as a way of stabilizing his tense relationship with Lord Corlys Velaryon. Rhaenyra did not want to marry Laenor, but accepted the match when Viserys threatened to change the order of succession should she refuse. The two married in 114 AC, though it is rumored that they never had their marriage consummated as Laenor was rumored to be homosexual. Rhaenyra gave birth to her sons Prince Jacaerys ("Jace"), Prince Lucerys ("Luke"), and Prince Joffrey Velaryon in 114, 115, and 117 AC while Alicent gave birth to her third son Prince Daeron Targaryen in 114 AC, shortly after Jace.
==== Gender and sex bias ==== In 2014, it was announced that the NIH is directing scientists to perform their experiments with both female and male animals, or cells derived from females as well as males if they are studying cell cultures, and that the NIH would take the balance of each study design into consideration when awarding grants. The announcement also stated that this rule would probably not apply when studying sex-specific diseases (for example, ovarian or testicular cancer).
The velocity of the charged particle after acceleration will not change since it moves in a field-free time-of-flight tube. The velocity of the particle can be determined in a time-of-flight tube since the length of the path (d) of the flight of the ion is known and the time of the flight of the ion (t) can be measured using a transient digitizer or time to digital converter. Thus,
Sources: en.wikipedia.org
== Medical uses == In the EU, migalastat is indicated for the long-term treatment of people aged 16 years of age and older with a confirmed diagnosis of Fabry disease (alpha-galactosidase A deficiency) and who have an amenable mutation. In the US, migalastat is indicated for the treatment of adults with a confirmed diagnosis of Fabry disease and an amenable galactosidase alpha gene (GLA) variant based on in vitro assay data. An "amenable" mutation is one that leads to misfolding of the enzyme, but otherwise would not significantly impair its function. Based on an in vitro test, Amicus Therapeutics has published a list of 269 amenable and nearly 600 non-amenable mutations. About 35 to 50% of people with Fabry have an amenable mutation.
== Pharmacokinetics == Tofisopam is also claimed to be a PDE10A inhibitor, which may provide an alternative mechanism of action for its various therapeutic effects, and this action has been proposed to make tofisopam potentially useful as a treatment for schizophrenia. Tofisopam has been shown to act as an inhibitor of the liver enzyme CYP3A4, and some researches suspect that this could cause dangerous drug interactions with other medications metabolised by this enzyme, although the clinical significance of these findings remains unclear.
The Pradhan Mantri Matsya Sampada Yojana (PMMSY) (http://pmmsy.dof.gov.in/) is an initiative launched by the Government of India to establish a comprehensive framework and reduce infrastructural gaps in the fisheries sector. The scheme was announced by the Finance Minister, Nirmala Sitharaman while presenting the Union budget for 2019–20 in the parliament of India on 5 July 2019. The government intends to place India in the first place in fish production and processing by implementing Neeli Kranti (transl. Blue Revolution). This scheme is in line with governments aim to double the farmers' income by 2022–23.
Ricin ( RY-sin) is a lectin (a carbohydrate-binding protein) and a highly potent toxin produced in the seeds of the castor plant, Ricinus communis. The median lethal dose (LD50) of ricin for mice is around 22 micrograms per kilogram of body mass via intraperitoneal injection. Oral exposure to ricin is far less toxic. An estimated lethal oral dose in humans is approximately one milligram per 2 kilogram of body mass. Ricin is a toxalbumin and was first discovered by Peter Hermann Stillmark, the founder of lectinology. Ricin is chemically similar to robin.
Sources: en.wikipedia.org
Solid peptide is best kept frozen at about minus 20 degrees Celsius in a sealed container with desiccant. It should be allowed to reach room temperature before opening to prevent condensation. Repeated warming and cooling of the same vial is discouraged.
Reversed-phase liquid chromatography establishes purity, while mass spectrometry confirms molecular mass. The two techniques are normally used together. Retention time alone is not sufficient evidence of identity.
Different counterions change the mass per unit of peptide and can shift chromatographic behavior. Two samples of equal stated purity may therefore not be directly comparable. Reports should specify the counterion whenever quantitative comparisons are made.
Semax is a synthetic seven-amino-acid peptide derived from a fragment of corticotropin. It is used in Russia as a nasal preparation, while elsewhere it is studied as a research compound. It is not approved as a medicine in most countries.