The short version of intranasal delivery fits in a sentence. The long version — which is the one that helps — is below.
This page was last updated on 2026-06-22 and is reviewed periodically as new material appears.
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.
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.
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 |
|---|---|---|
| Typical analytical method | Reversed-phase HPLC with UV detection | Separates target peptide from truncated and oxidised forms |
| Identity confirmation | LC-MS or ESI-MS | Compares observed and calculated molecular ion |
| Primary degradation route | Methionine oxidation | Forms the sulfoxide; monitored as an early-eluting peak |
| Short-term storage | 2 to 8 degrees Celsius | Applies to working vials and reconstituted portions |
| Common synonyms | ACTH(4–10) analogue, MEHFPGP | Descriptive names used in laboratory catalogues |
Proposed mechanisms center on neurotrophic signaling rather than on classical melanocortin receptor activation. Rodent experiments have reported shifts in the expression of brain-derived neurotrophic factor and nerve growth factor after administration, together with changes in the associated receptor systems. Several authors argue that the peptide acts largely through its degradation products and their interaction with peptidergic pathways, but this remains a hypothesis rather than a settled finding. No single molecular target has been identified in a way that the field broadly accepts.
Published research covers ischemic stroke, traumatic brain injury, cognitive impairment, optic nerve conditions and attention-related measures. Much of the human evidence comes from small trials conducted in one country, which limits how far the results generalize. Animal models supply the larger share of the data, and effects seen in rodents do not transfer automatically to people. Reviews have noted that methodological reporting is often incomplete, making it difficult to pool results or compare treatment schedules across studies.
Pharmacokinetic accounts emphasize rapid breakdown. After intravenous dosing the intact peptide disappears from blood within minutes, and nasal delivery produces low but measurable concentrations. Metabolites rather than the parent molecule may account for part of the observed activity, although the relative contribution is unresolved. Dosing in the literature varies widely and no optimal schedule has been agreed. These gaps are regularly cited as a reason the findings have not produced broad clinical adoption beyond the original research setting.
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.
Semax is a synthetic heptapeptide with the sequence Met-Glu-His-Phe-Pro-Gly-Pro. Its chain combines the first seven residues of corticotropin with a C-terminal proline-glycine-proline extension, a modification intended to slow enzymatic breakdown. The free peptide has a molecular mass near 813.9 daltons. It belongs to the class of ACTH-derived fragments studied for central nervous system activity rather than for adrenal steroid stimulation. This structural relationship to a natural hormone fragment is the usual starting point for describing the compound in the literature.
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.
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.
== Safety and adverse effects == In immunocompromised individuals, S. boulardii has been associated with fungemia or localized infection, which may be fatal. Overall, S. boulardii is safe for use in otherwise healthy populations and fungemia with S. boulardii has not been reported, to the best of the recent evidence in immunocompetent patients. A review of HIV-1-infected patients given therapy with S. boulardii indicated it was safe. A retrospective study on 32,000 oncohematological hospitalized patients showed no occurrence of fungal sepsis with S. boulardii use.
Many cooks and food writers use the terms broth and stock interchangeably. In 1974, James Beard (an American cook) wrote that stock, broth, and bouillon "are all the same thing". While many draw a distinction between stock and broth, the details of the distinction often differ. One possibility is that stocks are made primarily from animal bones, as opposed to meat, and therefore contain more gelatin, giving them a thicker texture. Another distinction that is sometimes made is that stock is cooked longer than broth and therefore has a more intense flavour. A third possible distinction is that stock is left unseasoned for use in other recipes, while broth is salted and otherwise seasoned and can be eaten alone.
== Signs and symptoms == MELAS is a condition that affects many of the body's systems, particularly the brain and nervous system (encephalo-) and muscles (myopathy). As such, it is commonly referred to as a mitochondrial encephalomyopathy, due to the co-occurrence of these pathologies. In most cases, the signs and symptoms of this disorder appear in childhood following a period of normal development. Children with MELAS often have normal early psychomotor development until the onset of symptoms between 2 and 10 years old. Though less common, infantile onset may occur and may present as failure to thrive, growth retardation and progressive deafness. Onset in older children typically presents as recurrent attacks of a migraine-like headache, anorexia, vomiting, and seizures. Children with MELAS are also frequently found to have short stature. Most people with MELAS have a buildup of lactic acid in their bodies, a condition called lactic acidemia. Increased acidity in the blood can lead to vomiting, abdominal pain, extreme tiredness (fatigue), muscle weakness, loss of bowel control, and difficulty breathing. Less commonly, people with MELAS may experience involuntary muscle spasms (myoclonus), impaired muscle coordination (ataxia), hearing loss, heart and kidney problems, diabetes, epilepsy, and hormonal imbalances. Lactic acidemia also promotes mitochondrial dysfunction, one of the hallmarks of MELAS pathophysiology.
In many high and middle income countries lower socioeconomic status is a strong predictor of smoking. Smoking rates in the United States have dropped by more than half from 1965 to 2016, falling from 42% to 15.5% of US adults. Australia is cutting their overall smoking consumption faster than most of the developed world, in part due to the landmark Plain Packaging Act, which standardized the appearance of cigarette packs. Other countries have considered similar measures. In New Zealand, a bill has been presented to Parliament which the government's associate health minister said "takes away the last means of promoting tobacco as a desirable product."
Sources: en.wikipedia.org
== Plot == Damon Fields is born to a single teenage mother in a trailer home in Lee County, in the Appalachian Mountains of Virginia. He is nicknamed "Demon Copperhead" for his red hair, dark skin and light eyes, inherited from his Melungeon father who drowned at a swimming hole called the Devil's Bathtub. Throughout the book, Demon is fascinated with the ocean and longs to see it one day. Demon spends much of his time with their neighbors, Mr. and Mrs. Peggot, who are raising their grandson Matt Peggot (nicknamed Maggot). Maggot and Demon are the same age and become best friends. When Demon is in elementary school, his mother begins a relationship with a trucker named Stoner, who becomes abusive. One summer, the Peggots take Demon on a trip to Knoxville, where he meets and is captivated by Maggot’s aunt June and her adopted daughter Emmy. On Demon’s trip to Knoxville, his mother marries Stoner, whose behavior becomes even more abusive. She relapses into her former drug addiction and ODs. Stoner pays for her to be sent to rehab and Demon is put in short-term foster care. His foster home is at Creaky Farms, run by Mr. Crickson who fosters another three young boys; Fast Forward, the quarterback for the Lee High School Generals football team, Swap-Out, who is mentally ill, and Tommy, who bonds with Demon over their shared love of drawing. The living conditions are squalid and Crickson forces the foster kids to assist with farm work, including tobacco harvesting.
== The leading research groups, producers and applications == One of the leading groups in academy for creating ion-trap MMS is Prof. Graham Cooks with his associate Professor Zheng Ouyang at Purdue University. They have built a series of mini mass spectrometer based on quadrupole ion trap called Mini 10, Mini 11, Mini 12. The group used Mini 10 mass spectrometer weighing 10 kg to analyze proteins, peptides and alkaloids in complex plant materials with electrospray ionization ESI and paperspray ionization. The group used low radio frequency of resonant ion ejection to increase mass range up to 17,000 Da proteins. For interfacing ESI source with MMS, a 10 cm stainless steel capillary was fabricated to transfer the ions directly into the vacuum manifold. The resulting high pressure of 20 mTorr, which is several orders of magnitude higher than that used in lab-scale mass spectrometers is compensated by using the pressure-tolerant rectilinear ion trap. One of the key component of this MMS is the commercial turbo-bump and the MS can be operated at 10−3 torr. To overcome the problem of continuous sample introduction because of the small size of the pump, the group developed a technique called discontinuous atmospheric pressure introduction (DAPI). This technique performs direct chemical analysis without sample pretreatment and enables the coupling of miniature mass spectrometers to atmospheric pressure ionization sources, including ESI, atmospheric pressure chemical ionization (APCI), and various ambient ionization sources.
=== Manufacturing === Packaging lines can have a variety of equipment types: integration of automated systems can be a challenge. All aspects of food production, including packaging, are tightly controlled and have regulatory requirements. Uniformity, cleanliness and other requirements are needed to maintain Good Manufacturing Practices. Product safety management is vital. A complete Quality Management System must be in place. Hazard Analysis and Critical Control Points is one methodology which has been proven useful. Verification and validation involves collecting documentary evidence of all aspects of compliance. Quality assurance extends beyond the packaging operations, through distribution and cold chain management.
Sources: en.wikipedia.org
Dry powder is usually kept at about -20 degrees Celsius for long-term storage and at 2 to 8 degrees Celsius for short working periods. Containers should stay sealed and protected from light and moisture to limit degradation.
Oxidation of the methionine residue to the sulfoxide is a frequently reported change, and it usually appears as an earlier-eluting peak in reversed-phase chromatography. Backbone hydrolysis products can also accumulate in aqueous solution.
Liquid chromatography coupled with mass spectrometry is the usual approach, because the observed molecular ion can be compared with a calculated mass of about 813.9 Da. Retention time alone does not establish identity.
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.