A practical reference on Intranasal delivery: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2025-08-16. Anything still debated is marked as such rather than presented as settled.
Proposed mechanisms centre on the GABAergic system. Animal and tissue studies report changes in GABA-A receptor expression and reduced activity of GABA transaminase, the enzyme that degrades GABA. Effects on monoamine turnover, including serotonin and dopamine pathways, are also described, and a separate line of work links the peptide to increased expression of brain-derived neurotrophic factor in hippocampal tissue. Most of these findings come from rodent models and cell preparations. How the individual observations combine into a single coherent mode of action is not settled.
Pharmacokinetic data are sparse and largely derived from animal work. After intranasal administration the peptide appears in plasma within minutes, and reported half-lives are short, on the order of minutes to tens of minutes. Degradation proceeds through ordinary proteolytic cleavage into constituent amino acids and smaller fragments. Direct evidence that intact Selank reaches brain tissue in meaningful amounts is limited, and the extent of blood-brain barrier penetration is debated. Some authors argue that fragments, not the parent peptide, carry much of the observed activity.
Animal studies have examined behaviour in tests of anxiety, memory retention and stress response, and several report changes in neurotrophic or neurotransmitter-related markers. The human evidence base is much smaller, consisting mainly of short trials conducted in Russia with limited reporting in English-language journals. Sample sizes are modest and outcome measures vary between studies, so the findings are best described as preliminary. Independent replication under modern trial standards has not been widely reported.
Outside its country of origin the compound is generally handled as a research chemical rather than an approved medicine. No regulatory approval from the United States Food and Drug Administration or the European Medicines Agency has been granted for human use. Identity and purity are normally checked by reverse-phase high-performance liquid chromatography, with mass spectrometry used to confirm the molecular mass. Lyophilised material is stored cold and desiccated, and repeated freeze-thaw cycles are avoided.
| Property | Value | Notes |
|---|---|---|
| Primary route studied | Intranasal | Also examined parenterally in animal work |
| Reported plasma half-life | Minutes to tens of minutes | Values vary widely between reports |
| Main model systems | Rodent behavioural and cell assays | Human trials are few and small |
| Principal proposed targets | GABA-A receptor, GABA transaminase | Monoamine and neurotrophic pathways also reported |
| Evidence grade | Preliminary | Limited independent replication |
Regulatory status differs sharply by region. Selank holds a Russian marketing authorization, where it is supplied mainly as nasal drops, while authorities elsewhere have not approved it for medical use. Material sold internationally is therefore usually labeled as a research chemical rather than a medicine. Peer-reviewed publications come predominantly from Russian laboratories, and sample sizes are generally small. Whether the compound produces comparable effects under independent, well-controlled replication remains an open question that the broader literature has not settled.
Selank is a synthetic heptapeptide developed in Russia as a structural analogue of tuftsin, a naturally occurring immunomodulatory tetrapeptide. Its sequence, Thr-Lys-Pro-Arg-Pro-Gly-Pro, keeps the tuftsin core at the N-terminus and appends a Pro-Gly-Pro tail. Researchers at the Institute of Molecular Genetics in Moscow synthesized the compound during the 1990s while searching for peptides with combined anxiolytic and immunomodulatory activity. The added tail was intended to resist enzymatic cleavage and prolong the molecule's presence in circulation.
The compound has a calculated molecular weight near 751.9 daltons and carries a net positive charge at physiological pH because of its arginine residue. It dissolves freely in water and in common aqueous buffers, and typically appears as a white or off-white lyophilized powder. The amide backbone makes the molecule susceptible to peptidases, which limits oral use and favors intranasal or parenteral routes. Nomenclature in the literature varies: the substance is also described by the sequence abbreviation TP-7 and by a Russian trade designation.
Dry powder is normally held at -20 degrees Celsius or lower, in a sealed container with desiccant and protection from light. Reconstituted solutions are usually kept at 2 to 8 degrees Celsius for short periods and frozen for longer ones. Proline residues at several positions are generally associated with some resistance to peptidase attack, but chemical stability still declines at neutral to alkaline pH and at elevated temperature. Exact shelf-life figures are product-specific and are not standardised across suppliers.
Identity and purity are usually assessed by reversed-phase high-performance liquid chromatography, with mass spectrometry used to confirm molecular mass and sequence information. Amino acid analysis and peptide mapping may supplement these methods. Certified reference standards are scarce, and many commercial lots are sold as research chemicals without a pharmacopoeial monograph. Regulatory treatment differs by country: Selank is a registered prescription medicine in Russia, while in the European Union and the United States it is not an approved drug and may fall under research-chemical or unapproved-product frameworks.
Gauze: Composed of woven or non-woven cotton, rayon, and polyester, gauze is highly absorbent, but removal can be uncomfortable. Films: Films are made of translucent polyurethane which is adherent to skin and semi-occlusive, allowing them to retain within the dressing but also allow for exchange of gases such as oxygen and carbon dioxide. The translucent nature of this dressing makes monitoring wounds simple. Hydrocolloids: Consist of an outer, water-impermeable layer and an inner layer made of colloid. When the inner colloid layer comes in contact with liquid, it becomes a gel allowing the dressing to maintain a moist environment while simultaneously absorbing exudate. Hydrocolloids cause minimal pain on removal but are at increased risk of skin maceration and bacterial growth. Hydrogels: An insoluble, hydrophilic material with soothing properties which is useful in treating burn wounds, dry chronic wounds, and pressure ulcers. Like hydrocolloids, hydrogels are capable of retaining excess moisture leading to skin maceration and bacterial growth. Foams: A flexible material with a hydrophobic outer layer that shields liquid from the outside environment, while having a highly absorptive inner layer which is ideal for highly exuding wounds. Foams should not be used in dryer wounds that require exudate to stay moist. Alginates: Derived from seaweed, alginates can absorb up to 15–20 times their weight in liquid and are ideal for highly exudative wounds. Like hydrocolloids, alginates form a gel when they come in contact with fluid, making removal relatively painless.
Alistair Barkley who goes on the run with Eddie when they are framed for Alistair's murder and the destruction of his laboratory Fred Ward as FBI Agent Leon Ford, who leads the investigation to discover the cause of the destruction of the laboratory; initially focusing on Eddie and Lily, he soon suspects the involvement of government organizations Kevin Dunn as FBI Agent Doyle, Ford's assistant in the investigation who helps Ford track down Eddie, Lily, and later, C-Systems Brian Cox as Lyman Earl Collier, Chairman of C-Systems Research who is behind the conspiracy to keep the hydrogen power plant a secret Joanna Cassidy as Maggie McDermott, an old friend of Eddie's who lives in an observatory in Wisconsin, where Eddie and Lily escape to after a warrant is issued for their arrest Chelcie Ross as FBI Agent Ed Rafferty Nicholas Rudall as Dr. Alistair Barkley, head of the project to develop energy from the water who is later suffocated Tzi Ma as Lu Chen, Project Manager on the Hydrogen Project and Dr. Barkley's right-hand man; when Barkley is killed, Dr. Chen is kidnapped and forced to work at C-Systems Krzysztof Pieczyński as Lucasz Screbneski, the scientist on the original project who is secretly working for C-Systems Eddie Bo Smith Jr. and Danny Goldring as Yusef Reed and Clancy Butler, Collier's right hand men for C-Systems Margaret Travolta as Anita Fermi, Shannon's personal assistant. In addition, Michael Shannon and Neil Flynn make appearances as a van driver and a Wisconsin State Police Trooper, respectively.
DiCaprio earned nominations for a Golden Globe and a BAFTA Award for the film. It broke the record for the most views (152 million hours) in a single week in Netflix history. DiCaprio next starred in Scorsese's crime drama Killers of the Flower Moon (2023) based on the book of the same name by David Grann, for which he was paid $30 million. Initially signed for the heroic part of FBI agent Thomas Bruce White Sr., DiCaprio insisted on playing the morally complex role of murderer Ernest Burkhart, leading to extensive script rewrites. Declaring it the best performance of DiCaprio's career, IndieWire's David Ehrlich wrote that "his nuanced and uncompromising turn as the cretinous Ernest Burkhart mines new wonders from the actor's long-standing lack of vanity". He received another Golden Globe nomination for his performance. DiCaprio next starred in Paul Thomas Anderson's film One Battle After Another (2025), alongside Sean Penn and Regina Hall. For his role as a washed-up ex-revolutionary, he received his seventh Academy Award acting nomination. In December 2025, DiCaprio confirmed he has been cast in an undisclosed role in Michael Mann's planned sequel to the 1995 film Heat. As of February 2026, DiCaprio began shooting What Happens at Night, helmed by Martin Scorsese, also starring Jennifer Lawrence and Mads Mikkelsen.
=== Insomnia === In all of the reported cases, the need for sleep was severely reduced and in some cases not necessary. The duration of sleep in one case decreased to about 2–4 hours per 24-hour period. Clinical features pertaining to insomnia include daytime drowsiness associated with a loss of ability to sleep, intermingled with confusional oneiric status, and the emergence of atypical REM sleep from wakefulness. The polysomnogram (PSG) picture of this disease is characterized by an inability to generate physiological sleep (key features are the suppression of the hallmarks of stage 2 non-REM sleep: spindles and K complexes) and by the emergence of REM sleep without atonia. The involvement of the thalamus and connected limbic structures in the pathology indicate the prominent role that the limbic thalamus plays in the pathophysiology of sleep. In a case documented in 1974, PSG findings documented the sustained absence of all sleep rhythms for up to a period of 4 months. Electroencephalography (EEG) in one case was dominated by "wakefulness" and “subwakefulness” states alternating or intermingled with short (< 1 min) atypical REM sleep phases, characterized by a loss of muscle atonia. The “subwakefulness” state was characterized by 4–6 Hz theta activity intermingled with fast activity and desynchronized lower voltage theta activity, behaviourally associated with sleep-like somatic and autonomic behavior.
Sources: en.wikipedia.org
Ethanol is also known chemically as alcohol, ethyl alcohol, or drinking alcohol. It is a simple alcohol with a molecular formula of C2H6O and a molecular weight of 46.0684 g/mol. The molecular formula of ethanol may also be written as CH3−CH2−OH or as C2H5−OH. The latter can also be thought of as an ethyl group linked to a hydroxyl (alcohol) group and can be abbreviated as EtOH. Ethanol is a volatile, flammable, colorless liquid with a slight characteristic odor. Aside from its use as a psychoactive and recreational substance, ethanol is also commonly used as an antiseptic and disinfectant, a chemical and medicinal solvent, and a fuel.
=== Process of definition === To define the IU for a substance, an international collaborative study is organized by the WHO Expert Committee on Biological Standardization using various assay systems in several laboratories. The main goal of the study is to reach a consensus regarding methods of analysis and the approach to standardization so that results can be compared. The study is performed using highly purified preparations of the substance, typically in lyophilized form, called international reference preparations, or IRPs. Each preparation is divided into precisely weighed samples, with each sample stored in its own ampoule labeled with a code corresponding to the source IRP. Assays are performed using these samples and are calibrated against the previously available IU standard. These results can be quite variable; the final IU value for samples of a given IRP are determined by consensus. The IRP that provides the best results and shows the best long term stability is selected to define the next IU. This IRP is then referred to as the international standard. When a standard sample comes close to depleting, a new standard will have to be found. A new batch of the substance in question is produced and calibrated against the old one, so that the unit still represents the same amount of biological activity. Many substances have undergone several such standard sample changes. The third international standard of prolactin has nearly run out and in 2016 replacement was proposed.
The drug fenethylline has played a role in the Syrian civil war. The production and sale of fenethylline generates large revenues which are likely used to fund the purchase of weapons, and fenethylline is used as a stimulant by combatants. Poverty and international sanctions that limit legal exports are contributing factors. In May 2021, The Guardian described the effects of fenethylline production in Syria on the economy as "a dirty business that is creating a near-narco-state". Drug money flowing into Syria is destabilizing legitimate businesses, positioning it as the global centre of fenethylline production, with increased industrialization, adaptation, and technical sophistication. In June 2021, Saudi authorities at Jeddah port seized 14 million fenethylline tablets hidden inside a shipment of iron plates coming from Lebanon. In the same month, Saudi authorities seized a shipment of 4.5 million fenethylline pills, smuggled inside several orange cartons, at Jeddah port. In July 2021, Saudi customs discovered 2.1 million fenethylline pills at Al-Haditha hidden in a tomato paste shipment. In December 2024, shortly after the Assad government collapsed, Syrian former-rebels found warehouses filled with Captagon alongside factory equipment to make it and also found some Captagon pills inside the copper coils of new voltage stabilisers, showing one way the former Syrian government used to smuggle Captagon out of the country.
Jackson-Pratt drain – consists of a perforated round or flat tube connected to a negative pressure collection device. The collection device is typically a bulb with a drainage port which can be opened to remove fluid or air. After compressing the bulb to remove fluid or air, negative pressure is created as the bulb returns to its normal shape. Blake drain – a round silicone tube with channels that carry fluid to a negative pressure collection device. Drainage is thought to be achieved by capillary action, allowing fluid to travel through the open grooves into a closed cross section, which contains the fluid and allows it to be suctioned through the tube. Penrose drain – a soft rubber tube. Negative pressure wound therapy – Involves the use of enclosed foam and a suction device attached; this is one of the newer types of wound healing/drain devices which promotes faster tissue granulation, often used for large surgical/trauma/non-healing wounds. Redivac drain – a high negative pressure drain. Suction is applied through the drain to generate a vacuum and draw fluids into a bottle. Shirley drain. Chest tube – is a flexible plastic tube that is inserted through the chest wall and into the pleural space or mediastinum.
=== Available forms === Elagolix is available in the form of Orilissa 150 and 200 mg oral tablets. The 150 mg tablets are light pink, oblong, and film-coated with "EL 150" debossed on one side, while the 200 mg tablets are light orange, oblong, and film-coated with "EL 200" debossed on one side. The inactive ingredients in the tablets include mannitol, sodium carbonate monohydrate, pregelatinized starch, povidone, magnesium stearate, polyvinyl alcohol, titanium dioxide, polyethylene glycol, talc, and a distinct color additive (carmine high tint in the 150 mg tablets and iron oxide red in the 200 mg tablets).
Sources: en.wikipedia.org
=== Providers and locations for ESG performance === Accredited advanced fellowship training programs in ESG and other endoscopic bariatric therapies are currently rare, and competency in ESG is typically achieved through proctoring by experts after completion of an accredited gastroenterology or surgical training program. Studies have reported that efficiency with performance of ESG and improved weight loss outcomes occur after approximately 35-38 cases. Mastery was reported in one study to occur after 55 cases. While early performance of the ESG has traditionally been carried out in university-affiliated/academic centers, ESG has been shown to be feasible and safe when performed in the community setting.
=== Protein-type CSP === Proteins are complex, high-molecular weight biopolymers. They are inherently chiral being composed of L-amino acids and possess ordered 3D-structure. They are known to bind/interact stereoselectively with small molecules reversibly, making them extremely versatile CSPs for chiral separation of drug molecules. Hermansson made use of this property to develop number of CSPs by immobilizing proteins on to silica surface. They operate under reverse phase mode (phosphate buffer and organic modifiers). Protein polymer remains in twisted form because of the different intramolecular bonding. These bonding create different type of chiral loops/grooves present in the protein molecule. Separation mechanism of proteins depends on unique combination of hydrophobic and polar interactions by which the analytes are oriented to chiral surfaces. H-bonding and charge transfer may also contribute to enantioselectivity. The mechanism of chiral distinction by proteins is mostly not well established due to their complex nature. Several proteins based CSP have been employed for chiral drug analysis including α-acid glycoprotein (enantiopac; chiral-AGP), ovomucoid protein (Ultron ES DVM), human serum albumin (HSA). α-AGP CSP (chiral AGP), has been employed for the quantification of atenolol enantiomers in biological matrices, for pharmacokinetic investigation of racemic metoprolol. The major weakness of protein based CSPs include low loading capacity, protein phases are expensive, extremely fragile, delicate to handle, very low column efficiency, cannot invert elution order.
== Structure == Carboxypeptidase A (CPA) contains a zinc (Zn2+) metal center in a tetrahedral geometry with amino acid residues in close proximity around zinc to facilitate catalysis and binding. Out of the 307 amino acids bonded in a peptide chain, the following amino acid residues are important for catalysis and binding; Glu-270, Arg-71, Arg-127, Asn-144, Arg-145, and Tyr-248. Figure 1 illustrates the tetrahedral zinc complex active site with the important amino acid residues that surround the complex. The zinc metal is a strong electrophilic Lewis acid catalyst which stabilizes a coordinated water molecule as well as stabilizes the negative intermediates that occur throughout the hydrolytic reaction. Stabilization of both the coordinated water molecule and negative intermediates are assisted by polar residues in the active site which are in close proximity to facilitate hydrogen bonding.
Size-exclusion chromatography, also known as molecular sieve chromatography, is a chromatographic method in which molecules in solution are separated by their shape, and in some cases size. It is usually applied to large molecules or macromolecular complexes such as proteins and industrial polymers. Typically, when an aqueous solution is used to transport the sample through the column, the technique is known as gel filtration chromatography, versus the name gel permeation chromatography, which is used when an organic solvent is used as a mobile phase. The chromatography column is packed with fine, porous beads which are commonly composed of dextran, agarose, or polyacrylamide polymers. The pore sizes of these beads are used to estimate the dimensions of macromolecules. SEC is a widely used polymer characterization method because of its ability to provide good molar mass distribution (Mw) results for polymers. Size-exclusion chromatography (SEC) is fundamentally different from all other chromatographic techniques in that separation is based on a simple procedure of classifying molecule sizes rather than any type of interaction.
Sources: en.wikipedia.org
Reports describe modulation of GABA signalling, changes in monoamine turnover and effects on neurotrophic factor expression. These observations come mainly from animal and cell studies. A single unifying mechanism has not been demonstrated.
The peptide enters plasma rapidly and is broken down by ordinary proteases into amino acids and shorter fragments. Reported half-lives are short. Whether meaningful amounts of the intact molecule reach the brain is an open question.
Most clinical reports are small, published in Russian and not independently replicated. English-language reviews highlight the absence of large randomised trials. Conclusions about efficacy should be treated as provisional.
Most published work uses intranasal application, either as drops or as a nasal spray. Injection routes appear in a smaller set of animal experiments. Oral use is uncommon in the literature because peptide breakdown and poor absorption limit this route.