nasal drops 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 2026-06-03. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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.
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.
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 |
|---|---|---|
| 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 |
Published research has focused mainly on neurological and cognitive endpoints in animal models, with proposed mechanisms involving brain-derived neurotrophic factor and related signalling pathways. A substantial share of the human data originates from a limited number of research groups, and independent replication in other countries remains sparse. Regulatory status reflects that distribution: the peptide is registered as a medicine in Russia and appears in some neighbouring markets, while elsewhere it is handled as a research chemical without approved therapeutic labelling. Questions about dose-response relationships, long-term effects, and comparability across studies are still open.
Lyophilised powder is normally kept at -20 °C in a desiccated container, with some suppliers recommending -80 °C for long-term archival storage. Repeated freeze-thaw cycles are the most common cause of avoidable loss, so aliquoting before freezing reduces variability between working sessions. Dissolved peptide is far less stable than the dry solid and is usually prepared fresh or held briefly at 4 °C. Aqueous solutions support both hydrolysis of the backbone and oxidation of the N-terminal methionine, and these two routes dominate degradation under ordinary laboratory conditions.
Identity and purity are confirmed with reversed-phase high-performance liquid chromatography, typically monitored at 214 nanometres where the peptide bond absorbs. Mass spectrometry, either electrospray or MALDI-TOF, verifies molecular mass against the theoretical value and detects truncation or adduct formation. Amino acid analysis and peptide mapping provide additional confirmation when required. The most frequently reported impurities are deletion sequences from incomplete coupling, methionine sulfoxide from oxidation, and dimeric species formed through non-covalent aggregation. Impurity profiles depend strongly on the synthesis and purification route chosen by the producer.
The proposed mechanism centres on neurotrophic signalling rather than direct receptor activation. Semax is reported to increase expression of brain-derived neurotrophic factor and nerve growth factor in several brain regions, and to shift the balance between excitatory and inhibitory neurotransmitter systems. Interaction with melanocortin receptors has been suggested because of the parent ACTH fragment. Many of these findings come from rodent studies, and the extent to which they translate to human physiology remains an open question.
Scientific literature on semax is unevenly distributed. A substantial share of published work originates from a small number of laboratories in Russia, while independent replication elsewhere is limited. Human data consist mostly of small trials with short follow-up, and several reported outcomes rely on subjective rating scales. Questions about how much intact peptide reaches the central nervous system after nasal administration, and how long it persists there, are still unresolved. The compound is best described as an active research subject rather than a settled pharmacological agent.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. It was derived from the ACTH(4-10) fragment, a short segment of adrenocorticotropic hormone that lacks the hormonal activity associated with the full-length peptide. Researchers at the Institute of Molecular Genetics in Moscow developed the compound during the 1980s. It has been registered as a pharmaceutical product in Russia and several neighbouring countries, where it is supplied as a nasal solution, and it is also sold internationally as a research chemical.
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.
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.
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.
Roeder and Robert Tjian, for their outstanding work on eukaryotic transcription regulation 1993 James E. Rothman and Randy Schekman, for determining the components of the secretory pathway 1992 Paul Nurse and Leland H. Hartwell, for establishing the details of the control of eukaryotic cell cycle 1991 David Botstein, Raymond L. White and Ronald W. Davis, for creating the methods by which variations in the human genome can be detected and analyzed 1990 Richard Henderson and Peter Nigel Tripp Unwin, for determining the first structure of an integral membrane protein 1989 Christiane Nüsslein-Volhard and Edward B. Lewis, for pioneering studies of eukaryotic development 1988 Sidney Altman and Thomas R. Cech, for discovering RNA catalysis 1987 Shinya Inoué, for his innovations in light microscopy 1986 Harland G. Wood, for his outstanding work on enzyme function 1985 Seymour Benzer and Sydney Brenner, for founding modern eukaryotic genetics 1984 Donald D. Brown and Robert L. Letsinger, for their seminal work on development 1983 Eric R. Kandel and Daniel E. Koshland, Jr., for pioneering contributions to sensory transduction 1982 Keith R. Porter and Alexander Rich 1981 Stanley Cohen, Rita Levi-Montalcini and Gordon H. Sato 1980 Elias J. Corey, Bengt I. Samuelsson and Frank H. Westheimer 1979 Howard Green and Beatrice Mintz 1978 César Milstein 1977 Barbara McClintock 1976 Peter D. Mitchell 1975 Bruce Ames, James A. Miller and Elizabeth C. Miller 1974 Arthur B. Pardee and H. Edwin Umbarger 1973 H. Ronald Kaback and Saul Roseman 1972 Boris Ephrussi 1971 David H. Hubel and Torsten N.
During his 2024 reelection campaign, the Electoral Courts permitted the removal of graffiti that portrayed Melo, partially submerged by flooding. The mural, dubbed Chimelo, was made by the artist Filipe Harp, and was based on an illustration by Bruno Ortiz Monllor. Chimelo was sprayed onto the wall of a cultural center in the Cidade Baixa neighborhood. In a decision rendered on 15 August, Judge Patrícia Hochheim Thomé judged that the panel had been framed as electoral propaganda in the locality or loosely covered by legislation. She ruled that the mural be removed within 24 hours, or be faced with a fine of $5,000 real in case of insubordination, and was rapidly covered up. In September of that year, however, the state Regional Electoral Court (TRE) reauthorized the reproduction of the mural. The art was understood by the Public Electoral Ministry (MPE) was to be interpreted and treated as elaborate art by a citizen who was not running as a candidate. Desembargador Nilton Tavares da Silva agreed with the notion and voted for the mural's authorization. The decision was supported by the court in a unanimous decision.
Derived from “the addition of a hydrophilic heterocyclic group to the α-amino group of ampicillin”, the structure consists of a thiazolidine ring conjoined to a β-lactam ring contained within several ring compounds. The addition of this substituent increases the compound's affinity to penicillin-binding protein PBP-3, improving activity against Gram-negative bacteria, and thus broadening its spectrum of activity. Susceptible β-lactamase producing bacteria such as Staphylococcus spp. or Haemophilus influenzae, the combination of tazobactam (which shares a similar structure to sulbactam, another β-lactamase inhibitor), and piperacillin significantly improves the stability of the drug against β-lactamases.
=== Second formation === The division was reconstituted starting in March 1945 and placed under the operational control of the 2nd Army (Army Group Vistula) in West Prussia. On 10 March 1945, the division was reformed near Schwedt with only two regiments. The "Shadow Division Hannover" was utilized for this purpose. Grenadier Regiment 1093 was not re-established, and the artillery regiment consisted of only a single battalion. Subsequently, the division was assigned to the 3rd Panzer Army and deployed on the Oder front against the Red Army. In May 1945, the 547th Volksgrenadier Division surrendered to US forces near Schwerin in Mecklenburg.
ASBMB Avanti Award for Lipid Research (1998) Elected to the American Academy of Arts and Sciences (1999) Heinrich Wieland Prize for Lipid Research (2000) Elected to the National Academy of Sciences (2001) Caledonian Prize from the Royal Society of Edinburgh (2002) Pezcoller-AACR International Award for Cancer Research (2005) Rolf Luft Award of the Karolinska Institute (2009) Pasrow Prize for Cancer Research (2011) Breakthrough Prize in Life Sciences (2013) Jacobaeus Prize for Diabetes Research, from the Karolinska Institute (2013) Elected to the Institute of Medicine of the National Academies (2014) AACR Princess Takamatsu Memorial Lectureship (2015) Ross Prize in Molecular Medicine (2015) Canada Gairdner International Award (2015) Elected to European life sciences academy EMBO (2015) The Association of American Cancer Institutes Distinguished Scientist Award (2015) Thomson Reuter's "The World's Most Influential Scientific Minds 2015". The Wolf Prize in Medicine (2016) The Hope Funds Award of Excellence in Basic Science (2016) Louisa Gross Horwitz Prize (2019) He appeared in the 60 Minutes program "Is sugar toxic?".
Sources: en.wikipedia.org
In 1998, the entire Festina team were excluded from the Tour de France following the discovery of a team car containing large amounts of various performance-enhancing drugs. The team director later admitted that some of the cyclists were routinely given banned substances. Six other teams pulled out in protest including Dutch team TVM who left the tour still being questioned by the police. The Festina scandal overshadowed cyclist Marco Pantani's tour win, but he himself later failed a test. The infamous "Pot Belge" or "Belgian mix" has a decades-long history in pro cycling, among both riders and support staff. David Millar, the 2003 World-Time Trial Champion, admitted using EPO, and was stripped of his title and suspended for two years. Roberto Heras was stripped of his victory in the 2005 Vuelta a España and suspended for two years after testing positive for EPO.
In the afternoon of 23 September, Xi Jinping boarded an Air China plane and left Beijing for Washington, D.C. He was accompanied by his wife Peng Liyuan, as well as Chinese Communist Party General Office director Cai Qi and Central Foreign Affairs Commission Office director and foreign minister Wang Yi. President Trump and First Lady Melania Trump left the White House at 16:39 EDT (UTC-4:00), and later arrived at Joint Base Andrews in Maryland. Xi's Air China plane landed at the base at 17:39, and a red carpet was placed for the Chinese delegation, who were also greeted by battery salute, three color teams carrying American and Chinese flags, and platoons from each military service. Trump personally greeted Xi, the first time the US President has greeted a foreign leader except the Pope at the base since John F. Kennedy met British prime minister Harold Macmillan in 1962. The United States Air Force Band played the national anthems of China and the United States and a 21-gun salute was fired on site. Two Rockwell B-1 Lancer bombers flew overhead to celebrate Xi's arrival. Trump walked Xi to his car, and afterwards departed to the Marine One by the presidential state car for a flight back to the White House.
Alberto E. Paniz-Mondolfi (born April 12, 1976) is a Venezuelan pathologist, epidemiologist, and molecular medicine researcher. Currently he is a pathologist and assistant professor in New York City and is affiliated with multiple hospitals in the area, including Mount Sinai Morningside and Mount Sinai West Hospitals and Mount Sinai Hospital. Also, he is the Academic Director and Founder of The Venezuelan Science Incubator (incubadorave.org), a group focused on infectious diseases research and awareness based in Venezuela.
However, on tests done on Drosophila melanogaster, nongenotoxic TCAs (amitriptyline, maprotiline, nortriptyline, and protriptyline), and genotoxic TCAs (amoxapine, clomipramine, desipramine, doxepin, imipramine, and trimipramine) were identified.
=== Produce === Unique to fresh produce cargoes, the cold chain requires to additionally maintain product specific environment parameters which include air quality levels (carbon dioxide, oxygen, humidity and others).
Sources: en.wikipedia.org
the alternation of late wood and early wood increments within the annual ring; the influence of wood rays on the radial direction; the features of the cell wall structure such as microfibril angle modifications and pits; the chemical composition of the middle lamella. Wood drying may be described as the art of ensuring that gross dimensional changes through shrinkage are confined to the drying process. Ideally, wood is dried to that equilibrium moisture content as will later (in service) be attained by the wood. Thus, further dimensional change will be kept to a minimum. It is probably impossible to completely eliminate dimensional change in wood, but elimination of change in size may be approximated by chemical modification. For example, wood can be treated with chemicals to replace the hydroxyl groups with other hydrophobic functional groups of modifying agents. Among all the existing processes, wood modification with acetic anhydride has been noted for the high anti-shrink or anti-swell efficiency (ASE) attainable without damage to wood. However, acetylation of wood has been slow to be commercialised due to the cost, corrosion and the entrapment of the acetic acid in wood. There is an extensive volume of literature relating to the chemical modification of wood. Drying timber is one method of adding value to sawn products from the primary wood processing industries.
South Korean immigration policy is relatively unique in that, as a consequence of its claim over the territory currently administered by North Korea, citizens of North Korea are regarded by the South as its own citizens by birth. As a result, North Korean refugees in China often attempt to travel to countries such as Thailand which, while not offering asylum to North Koreans, classifies them as unauthorized immigrants and deports them to South Korea instead of North Korea. At the same time, the policy has operated to prevent pro-North Korea Zainichi Koreans recognised by Japan as Chōsen-seki from entering South Korea without special permission from the South Korean authorities as, despite being regarded as citizens of the Republic of Korea and members of the Korean diaspora, they generally refuse to exercise that status.
plasmid Any small DNA molecule that is physically separated from the larger body of chromosomal DNA and can replicate independently. Plasmids are typically small (less than 100 kbp), circular, double-stranded DNA molecules in prokaryotes such as bacteria, though they are also sometimes present in archaea and eukaryotes.
== Fatty acid oxidation inhibition by malonyl-CoA == Malonyl-CoA signals glucose utilization and it controls the entry and oxidation of long-chain fatty acids (LCFA) in the mitochondria. Circulating glucose in the liver stimulates its uptake. Glucose oxidation produces citrate which can be converted to malonyl-CoA by acetyl-CoA carboxylase. Malonyl-CoA inhibits the carnitine palmitoyltransferase (CPT) that controls the entry and oxidation of LCFA. The glucose-derived malonyl-CoA prevents the oxidation of fatty acids and favors fatty acid esterification.
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 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.