Everything below concerns Lyophilized powder. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2025-08-15. Numbers and descriptions here follow the published literature rather than marketing material.
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.
The compound is registered in Russia as a pharmaceutical product, most commonly formulated as a nasal solution, and has been used in that setting since the 1990s. Outside that jurisdiction it is generally handled as a research chemical rather than an approved medicine. Regulatory status therefore differs sharply between countries, and material sold internationally may not correspond to the Russian pharmaceutical formulation. Documentation with commercial samples is typically limited to a certificate of analysis covering purity and identity, not clinical status or local legal classification.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It corresponds to the ACTH(4-7) fragment extended at the C-terminus by a Pro-Gly-Pro tripeptide, an addition intended to slow enzymatic breakdown. The molecular formula is C37H51N9O10S and the molecular mass is approximately 814 daltons. In the literature it is often described as an ACTH(4-10) analog, although that label reflects a naming convention as much as a precise structural relationship. The compound was developed in Russia and remains most closely associated with that research tradition.
Laboratory descriptions of the material are consistent across suppliers. It appears as a white to off-white lyophilized powder that dissolves readily in water and in polar organic solvents such as dimethyl sulfoxide. Aqueous solutions are clear and colorless at low concentrations. Because the peptide contains methionine, oxidation at the sulfur atom is a recognized degradation pathway, and handling notes usually call for protected, desiccated storage. Reported purity for research-grade lots is generally above 95 percent as measured by reversed-phase high-performance liquid chromatography.
| 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 |
Practical handling follows from those properties. Bulk material is best divided into single-use portions soon after receipt, because each thaw exposes the whole container to moisture and temperature cycling. Vials should be allowed to reach room temperature before opening to prevent condensation on the powder. Low-binding plasticware reduces loss of dilute solutions, and sterile filtration is used when a preparation must remain free of microbial growth. Records of batch number, reconstitution date and storage history are what allow a later analytical result to be interpreted meaningfully.
Identity and purity of Semax are established mainly by reversed-phase high-performance liquid chromatography coupled with mass spectrometry. The chromatographic trace gives a purity estimate as a percentage of total peak area, while electrospray or matrix-assisted laser desorption ionization confirms the molecular mass against the calculated value. Amino acid analysis and sequence-specific fragmentation provide further confirmation when a supplier's chain of custody is unclear. Vendors frequently quote a purity figure without stating the detection wavelength or the integration method, which limits how far one number can be compared with another.
The C-terminal Pro-Gly-Pro extension is not incidental. Proline-rich tails are known to resist several common peptidases, and the published literature attributes the longer half-life of Semax, relative to unmodified ACTH fragments, to this feature. The modification also removes the melanocyte-stimulating and corticosteroidogenic activity that characterizes longer ACTH-derived sequences. Because the molecule is small and hydrophilic, it is typically formulated as an aqueous solution for intranasal or parenteral delivery. Acetylation or amidation at the termini appears in closely related research peptides and shifts the mass by a fixed increment.
Reported pharmacological work centers on neurotrophic signaling, including changes in BDNF and NGF expression in hippocampal tissue in animal models. Human data come largely from studies conducted in Russia, and how well those results generalize to other populations remains an open question. Regulatory status differs sharply by jurisdiction: Semax is a registered prescription medicine in Russia, while it holds no approved marketing status in the United States or the European Union. Outside such jurisdictions it is generally handled as a research chemical, which affects both documentation and quality expectations.
Semax is a synthetic heptapeptide whose sequence is Met-Glu-His-Phe-Pro-Gly-Pro. It was developed as a fragment analog of adrenocorticotropic hormone, modeled specifically on the ACTH(4-10) region. The first four residues reproduce that fragment, while a Pro-Gly-Pro tripeptide is appended at the C-terminus. Work on the compound originated in Russia, where it entered clinical use as an intranasal preparation. Its sequence places it among short regulatory peptides studied for effects on the central nervous system rather than on the adrenal axis.
Solid semax is typically supplied as a lyophilised powder that is hygroscopic and sensitive to moisture, light, and repeated temperature cycling. Long-term storage of the dry peptide is generally recommended at approximately -20 degrees Celsius, while shorter working periods may use refrigeration at 2 to 8 degrees Celsius. Vials should remain tightly closed and desiccated when brought to room temperature, because condensation can damage the material before it is weighed. Dividing a batch into aliquots is preferable to thawing one container repeatedly.
Dissolution is normally performed in water, phosphate-buffered saline, or normal saline, since the peptide is freely soluble in aqueous media and is rarely handled with strong organic solvents. Solution pH should be kept near neutral, because extreme acidity or alkalinity accelerates backbone hydrolysis and encourages oxidation of the methionine side chain. Once dissolved, the material is less stable than the dry powder and is commonly divided into single-use portions and frozen. Buffers containing primary amines, such as Tris, are often avoided because of possible side reactions.
=== Chalcogen === Serine, homoserine, O-methylhomoserine and O-ethylhomoserine possess a hydroxymethyl, hydroxyethyl, O-methylhydroxymethyl and O-methylhydroxyethyl side chain; whereas cysteine, homocysteine, methionine and ethionine possess the thiol equivalents. The selenol equivalents are selenocysteine, selenohomocysteine, selenomethionine and selenoethionine. Amino acids with the next chalcogen down are also found in nature: several species such as Aspergillus fumigatus, Aspergillus terreus, and Penicillium chrysogenum in the absence of sulfur are able to produce and incorporate into protein tellurocysteine and telluromethionine.
The following table summarizes several budgetary statistics for the fiscal year 2015-2021 periods as a percent of GDP, including federal tax revenue, outlays or spending, deficits (revenue – outlays), and debt held by the public. The historical average for 1969-2018 is also shown. With U.S. GDP of about $21 trillion in 2019, 1% of GDP is about $210 billion. Statistics for 2020-2022 are from the CBO Monthly Budget Review for FY 2022.
== Chemistry == Tertiapin peptide is composed of 21 amino acids with the sequence: Ala-Leu-Cys-Asn-Cys-Asn-Arg-Ile-Ile-Ile-Pro-His-Met-Cys-Trp-Lys-Lys-Cys-Gly-Lys-Lys. The methionine residue is sensitive to oxidation, reducing the ability to block the ionic channels. Methionine can be substituted by glutamine in order to prevent the oxidation. The new synthesized peptide is named Tertiapin-Q and does not show any functional change as compared to the original peptide, which makes it a more suitable research tool.
Fibroblast growth factor 19 is a protein that in humans is encoded by the FGF19 gene. It functions as a hormone, regulating bile acid synthesis, with effects on glucose and lipid metabolism. Reduced synthesis, and blood levels, may be a factor in chronic bile acid diarrhea and in certain metabolic disorders.
Adrenomedullin (ADM) is a peptide hormone that plays an important role in various physiological processes throughout the human body. Initially discovered in 1993 from a pheochromocytoma, a tumor of the adrenal medulla, this 52-amino acid peptide is now recognized for its diverse effects, including vasodilation, regulation of blood pressure, and maintenance of the vascular system. ADM is widely expressed in tissues and also found in the circulation, exerting its influence on the cardiovascular, lymphatic, and endocrine systems, as well as demonstrating anti-inflammatory and tissue-protective properties. In humans, ADM is encoded by the ADM gene. A similar peptide named adreomedullin2 was reported in rats in 2004, which exhibits a similar function.
Sources: en.wikipedia.org
Hormonal therapy in oncology is hormone therapy for cancer and is one of the major modalities of medical oncology (pharmacotherapy for cancer), others being cytotoxic chemotherapy and targeted therapy (biotherapeutics). It involves the manipulation of the endocrine system through exogenous or external administration of specific hormones, particularly steroid hormones, or drugs which inhibit the production or activity of such hormones (hormone antagonists). Because steroid hormones are powerful drivers of gene expression in certain cancer cells, changing the levels or activity of certain hormones can cause certain cancers to cease growing, or even undergo cell death. Surgical removal of endocrine organs, such as orchiectomy and oophorectomy can also be employed as a form of hormonal therapy. Hormonal therapy is used for several types of cancers derived from hormonally responsive tissues, including the breast, prostate, endometrium, and adrenal cortex. Hormonal therapy may also be used in the treatment of paraneoplastic syndromes or to ameliorate certain cancer- and chemotherapy-associated symptoms, such as anorexia. Perhaps the most familiar example of hormonal therapy in oncology is the use of the selective estrogen-response modulator tamoxifen for the treatment of breast cancer, although another class of hormonal agents, aromatase inhibitors, now have an expanding role in that disease.
Only a few troops were directly registered and the practice was soon discontinued with new "mixed" groups being encouraged to join the WOSM member organization of their country of residence. In 1955, only two such groups were still active, a troop in Iraq that disbanded that year, and the first group to be so registered, the International Troop 1 in Yokohama. The only remaining directly registered Troop is the International Boy Scouts, Troop 1 located in Yokohama, Japan. Temporary recognition was extended to Scouts in displaced persons camps after World War II. In 1947, at WOSM's 11th conference the "Displaced Persons Division" of WOSM's bureau was established to register and support Scouts in displaced person camps in Austria, Northern Italy, and Germany. These Scouts did not receive the right of WOSM membership but gained recognition as Scouts under WOSM's bureau until they took up residence in a country that had a recognized national Scout organization, which they could join. The D.P. Division was closed on 30 June 1950.
Fishmeal and oil from residues instead of whole fish have a different composition with more ash and less protein, which may limit its potential use for aquaculture. As the salmon farming industry expands, it requires more wild forage fish for feed, at a time when seventy-five percent of the world's monitored fisheries are already near to or have exceeded their maximum sustainable yield. The industrial-scale extraction of wild forage fish for salmon farming then impacts the survivability of the wild predator fish who rely on them for food. An important step in reducing the impact of aquaculture on wild fish is shifting carnivorous species to plant-based feeds. Salmon feeds, for example, have gone from containing only fishmeal and oil to containing 40 percent plant protein. The USDA has also experimented with using grain-based feeds for farmed trout. When properly formulated (and often mixed with fishmeal or oil), plant-based feeds can provide proper nutrition and similar growth rates in carnivorous farmed fish. Another impact aquaculture production can have on wild fish is the risk of fish escaping from coastal pens, where they can interbreed with their wild counterparts, diluting wild genetic stocks. Escaped fish can become invasive, out-competing native species.
=== Homology === GsMTx-4 shares less than 50% of its sequence homology with all other known peptide toxins. The highest percentage of sequence homology is shared with other tarantula toxins that block voltage-gated calcium channels and voltage-gated potassium channels. The ICK, as well as the residues F4, D13, and L20, are conserved in these tarantula toxins.
=== Immunology === Immunology is the branch of medicine that deals with the immune system, a network of biological systems that protects humans from diseases. The immune system detects and responds to pathogens, such as viruses, bacteria, and parasites, as well as cancer cells and foreign bodies. Humans have two major immune subsystems: The innate immune system, which provides a preconfigured response (e.g. defensins, complement system) to broad groups of situations and stimuli; and the adaptive immune system, which provides a tailored response to each stimulus by developing an immunological memory of molecules previously encountered. Mechanisms common to both subsystems, include phagocytosis, humoural immunity, cell-mediated immunity.
Sources: en.wikipedia.org
Blood is drawn into a test tube containing liquid sodium citrate, which acts as an anticoagulant by binding the calcium in a sample. The blood is mixed, then centrifuged to separate blood cells from plasma (as prothrombin time is most commonly measured using blood plasma). In newborns, a capillary whole blood specimen is used. A sample of the plasma is extracted from the test tube and placed into a measuring test tube (Note: for an accurate measurement, the ratio of blood to citrate needs to be fixed and should be labeled on the side of the measuring test tube by the manufacturing company; many laboratories will not perform the assay if the tube is underfilled and contains a relatively high concentration of citrate—the standardized dilution of 1 part anticoagulant to 9 parts whole blood is no longer valid). Next an excess of calcium (in a phospholipid suspension) is added to the test tube, thereby reversing the effects of citrate and enabling the blood to clot again. Finally, in order to activate the extrinsic / tissue factor clotting cascade pathway, tissue factor (also known as factor III) is added and the time the sample takes to clot is measured optically. Some laboratories use a mechanical measurement, which eliminates interferences from lipemic and icteric samples.
Three enzymes present in different organisms and tissues are known to catalyse the oxidation of the pyrrole ring in tryptophan, giving the N-formyl deriative which is subsequently hydrolysed to kynurenine. These are tryptophan dioxygenase, indoleamine 2,3-dioxygenase and indoleamine 2,3-dioxygenase 2.
Similar to water, graphite oxide easily incorporates other polar solvents, e.g. alcohols. However, intercalation of polar solvents occurs significantly different in Brodie and Hummers graphite oxides. Brodie graphite oxide is intercalated at ambient conditions by one monolayer of alcohols and several other solvents (e.g. dimethylformamide and acetone) when liquid solvent is available in excess. Separation of graphite oxide layers is proportional to the size of alcohol molecule. Cooling of Brodie graphite oxide immersed in excess of liquid methanol, ethanol, acetone and dimethylformamide results in step-like insertion of an additional solvent monolayer and lattice expansion. The phase transition detected by X-ray diffraction and differential scanning calorimetry (DSC) is reversible; de-insertion of solvent monolayer is observed when sample is heated back from low temperatures. An additional methanol and ethanol monolayer is reversibly inserted into the structure of Brodie graphite oxide under high pressure conditions. Hummers graphite oxide is intercalated with two methanol or ethanol monolayers at ambient temperature. The interlayer distance of Hummers graphite oxide in an excess of liquid alcohols increases gradually upon temperature decrease, reaching 19.4 and 20.6 Å at 140 K for methanol and ethanol, respectively. The gradual expansion of the Hummers graphite oxide lattice upon cooling corresponds to insertion of at least two additional solvent monolayers.
== Acquisitions == In July 2016, Relief acquired FirstString Research, a clinical-stage biotech firm based in Charleston, South Carolina, US. In January 2021, Relief acquired German-based firm AdVita in a €25 million agreement to further their research into inhaled treatments for Acute respiratory distress syndrome. In May 2021, Relief acquired Swiss biotech firm Applied Pharma Research (APR), including its existing portfolio and all pipeline products, for CHF 72 million ($79 million).
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.
It is registered as a pharmaceutical product in Russia, where it is typically supplied as a nasal solution. In most other countries it is not an approved drug and is traded as a research chemical instead. Approval status depends entirely on the jurisdiction involved.