Everything below concerns melanocortin receptor. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.
Updated 2026-06-16. Numbers and descriptions here follow the published literature rather than marketing material.
Melanocortin receptors comprise five subtypes with distinct tissue distributions and functions. Melanotan-2 is described in the literature as a non-selective agonist that engages several of these subtypes, including MC1R, MC3R, MC4R, and MC5R. MC1R is the subtype most directly linked to melanin production in skin cells. Because the compound is not subtype-selective, its observed effects in experimental settings are generally attributed to activity across multiple receptor pathways rather than to a single target.
Melanotan-2 is a synthetic linear peptide built from seven amino acids arranged in a short chain. Its sequence is commonly written as Ac-Nle-Asp-His-D-Phe-Arg-Trp-Lys-NH2, which includes a modified N-terminus and an amidated C-terminus. The molecule belongs to the melanocortin family and acts as a receptor agonist. Structural features such as the D-phenylalanine residue and the Nle substitution are associated with increased stability against enzymatic degradation relative to the natural parent peptide.
Solid peptide kept dry at minus twenty degrees Celsius, shielded from light and moisture, is generally considered stable for extended periods. Solutions are divided into single-use aliquots and held at minus twenty or minus eighty degrees Celsius, because repeated freeze-thaw cycles promote aggregation and loss of material to container surfaces. Hydrolysis of the backbone and oxidation of tryptophan are the principal degradation routes in aqueous solution, and both accelerate at ambient temperature. Hygroscopic uptake after a vial is opened can also shift the actual mass weighed, which affects any concentration calculated from it.
Routine characterisation relies on reversed-phase high-performance liquid chromatography with ultraviolet detection near 214 nanometres, using a C18 column and a water-acetonitrile gradient containing trifluoroacetic acid. Electrospray ionisation mass spectrometry confirms the expected molecular mass and can reveal truncated or oxidised by-products that co-elute poorly. Sequence and stereochemistry require additional work, such as peptide mapping or amino acid analysis, because a chromatographic purity figure alone does not distinguish a diastereomer from the target peptide. Independent testing of research-grade material frequently shows measured content below the stated label, so a certificate of analysis is best read together with the method that produced it.
Melanotan-2 is handled in the laboratory as a lyophilised powder that dissolves readily in water, dimethyl sulfoxide and dimethylformamide, with limited solubility in ethanol. Stock solutions prepared in an organic solvent often precipitate when diluted into aqueous buffer, so gradual dilution with mixing is standard practice. The peptide carries a tryptophan residue and a histidine residue, both sensitive to oxidation and to alkaline conditions. Working solutions are therefore kept near neutral to slightly acidic pH, protected from light, and consumed within the same working session whenever that is practical.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C50H69N15O9 | Free base; salt forms differ |
| Molecular weight | Approximately 1024 g/mol | Calculated for the free base |
| Appearance | White to off-white powder | Typically supplied as a lyophilised solid |
| Solubility | Soluble in water and polar solvents | Poorly soluble in non-polar solvents |
| Typical storage | -20 degrees Celsius, dry, protected from light | Refers to the solid form |
Melanotan-2 is frequently confused with afamelanotide, a linear analogue authorised in the European Union for erythropoietic protoporphyria. The two compounds differ in chain length, ring structure and receptor selectivity, so findings for one cannot be transferred directly to the other. Published controlled human data on melanotan-2 remain sparse, and much of what circulates online derives from small studies or unpublished reports. Questions about effect size, dose-response behaviour and long-term safety therefore remain unresolved.
Melanotan-2 is a synthetic cyclic heptapeptide designed as an analogue of alpha-melanocyte-stimulating hormone. Its sequence incorporates a lactam bridge that constrains the peptide into a ring, which increases resistance to enzymatic breakdown relative to the natural hormone. Researchers at the University of Arizona synthesised the compound in the late 1980s and early 1990s while studying pigmentation pathways. It has never received marketing approval from any national medicines regulator. In the scientific literature it is usually described as a laboratory research reagent rather than a therapeutic product.
Lyophilised peptide powder is comparatively stable when kept dry, cold and protected from light. Once dissolved, the molecule is exposed to hydrolysis, oxidation and microbial growth, and degradation accelerates at higher temperatures and in alkaline solution. Repeated freeze-thaw cycles concentrate solutes and promote aggregation. Handling guidance for research peptides commonly clusters around freezer temperatures for powder and short refrigerated use for reconstituted solutions, with pH control and sterile technique applied throughout.
Verification of a purchased sample requires documentation linking a batch to a certificate of analysis, and that document should be read for the methods used rather than the headline purity figure. A single chromatographic percentage does not establish identity. Independent laboratories can perform identity and content assays, but no such test establishes that a product is suitable for human use. Claims about efficacy rest largely on small, early studies rather than on replicated controlled trials, and that gap remains open.
Early published reports described melanotan-2 as a tanning agent without sun protection, which means darkening is not the same as protection against ultraviolet radiation. Later studies explored the peptide in erectile dysfunction, hemorrhagic shock, and some skin conditions. No regulator in the United States or Europe has approved it for clinical use. Many products labelled melanotan-2 are sold without approval and their identity and purity are unverified. Its long-term safety in humans remains an open question.
Melanotan-2, also written Melanotan II, is a synthetic cyclic heptapeptide designed as an analogue of alpha-melanocyte-stimulating hormone. Its sequence is Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH2, and the lactam bridge between the aspartate and lysine side chains constrains the peptide into a ring. This structural change increases receptor affinity and metabolic stability relative to the native hormone. The compound was created in the 1980s as a research tool for studying pigmentation biology.
dropping point The temperature at which a grease changes from a semi-solid to a liquid state under standardized conditions, i.e. the upper limit at which the grease retains its structure, though not necessarily the maximum temperature at which it can be used.
England and Wales Annabel Sarah Jane Berry, lately Superintendent, Hampshire Constabulary. Jason Richard Davies, Assistant Chief Constable, South Wales Police. Ian John Dawson, lately Assistant Chief Constable, Lancashire Constabulary. Andrew James Duignan, lately Detective Constable, Merseyside Police. Karen Ross Findlay, Temporary Commander, Metropolitan Police Service. Christopher James Flanagan, lately Detective Inspector, South Yorkshire Police. Matthew William Gosling, Detective Chief Inspector, Metropolitan Police Service. Kam Hare, Inspector, Greater Manchester Police. Laura Catherine Elizabeth Hart, Special Chief Inspector, Merseyside Police. Natalie Horner, Detective Constable, Durham Constabulary. Paul Joseph Martin Keasey, Superintendent, Gloucestershire Constabulary. Edward James Ough, lately Superintendent, South Wales Police. John Price, Sergeant, West Midlands Police. Hayley Jenny Annette Sewart, Detective Chief Superintendent, Metropolitan Police Service. Benjamin Daniel Snuggs, Deputy Chief Constable, Thames Valley Police. Amanda Jane Stephenson, Detective Inspector, Metropolitan Police Service. Matthew Wesley Ward, Deputy Assistant Commissioner, Metropolitan Police Service. Owen Robert Weatherill, lately Assistant Chief Constable, Hertfordshire Constabulary and National Police Co-ordination Centre. Scotland Faroque Hussain, Temporary Assistant Chief Constable, Police Service of Scotland. Carol McGuire, Chief Superintendent, Police Service of Scotland. Stephanie Rose, Police Constable, Police Service of Scotland.
The Association for Diagnostics & Laboratory Medicine (formerly known as the American Association for Clinical Chemistry or AACC) is a global scientific society dedicated to clinical laboratory science and its application to healthcare. ADLM's current president is Octavia M. Peck Palmer, PhD, FAAC, and the association headquarters are located in Washington, D.C. (United States).
==== Other actions ==== Unlike some other opioids and opioid antagonists, buprenorphine binds only weakly to and possesses little if any activity at the sigma receptor. Buprenorphine also blocks voltage-gated sodium channels via the local anesthetic binding site, and this underlies its potent local anesthetic properties. Similarly to various other opioids, buprenorphine has also been found to act as an agonist of the toll-like receptor 4, albeit with very low affinity.
Sources: en.wikipedia.org
Furthermore, water conservation is also accomplished as insects are cold-blooded and are able to meet water requirements through their feed. Thus, insects may be an acceptable source of protein for pets. To learn more about sustainability of insect rearing, see Insect farming.
Domino's Pizza Israel was founded in 1990, and opened their first branch in 1993. They are operated by Elgad Pizza. As of August 2014, there are 33 branches throughout the state. There are four kosher franchises. The rights to own, operate, and franchise branches of the chain in Australia, New Zealand, France, Belgium, the Netherlands, Monaco, Luxembourg, Germany, Japan, Malaysia, Singapore, Taiwan and Cambodia are currently owned by Australian Domino's Pizza Enterprises, having bought the master franchises from the parent company in 1993 (Australian and New Zealand franchises). The Australian company also acquired several European and Asian franchises between 2013 and 2022. It acquired the Danish operations in 2019 but liquidated them in 2023. The master franchises for the UK and Ireland were purchased in 1993 by the British publicly listed Domino's Pizza Group (DPG), which acquired the master franchise for Germany in 2011, and Switzerland, Liechtenstein, and Luxembourg in August 2012 by buying the Swiss master franchise holder, with an option to acquire the Austrian master franchise as well. DPG opened its first Swedish location near the Mobilia shopping mall in Malmö in December 2016; three years later, in 2019, they announced that they would be selling all of their current businesses in the country. In Latin America, the first franchise was opened in 1988 in Colombia. During the next years, Domino's Pizza started operations in Mexico, Guatemala (1989), Chile (1991), Venezuela (1992), Dominican Republic (1993), Ecuador and Peru (1995).
He was also listed in GQ India's "Best Dressed Men" rankings in 2010, 2012, 2015, and 2017. In 2023, he was placed 19th in 30 All Time Famous Bollywood Actors of All Time. Moreover, he was inducted into the Gladrags Hall of Fame.
However, the biological effects of radiation due to radioactive substances were less easy to gauge. This gave the opportunity for many physicians and corporations to market radioactive substances as patent medicines. Examples were radium enema treatments, and radium-containing waters to be drunk as tonics. Marie Curie protested against this sort of treatment, warning that "radium is dangerous in untrained hands". Curie later died from aplastic anaemia, likely caused by exposure to ionizing radiation. By the 1930s, after a number of cases of bone necrosis and death of radium treatment enthusiasts, radium-containing medicinal products had been largely removed from the market (radioactive quackery).
== Accidents == Ethylene oxide is extremely flammable, and its mixtures with air are explosive. When heated it may rapidly expand, causing fire and explosion. Several industrial accidents have been attributed to ethylene oxide explosion. The autoignition temperature is 429 °C (804 °F), decomposition temperature of 571 °C (1,060 °F) at 101.3 kPa (14.69 psi), minimum inflammable content in the air is 2.7%, and maximum limit is 100%. The NFPA 704 rating is Health, 3; Flammability, 4; Instability 2. Ethylene oxide in presence of water can hydrolyze to ethylene glycol and form polyethylene oxide, which then eventually is oxidized by air and leads to hotspots that can trigger explosive decomposition. Fires caused by ethylene oxide are extinguished with conventional media including foam, carbon dioxide, or water. Suppression of this activity can be done by blanketing with an inert gas until total pressure reaches the nonexplosive range. Extinguishing of burning ethylene oxide is complicated by its ability to continue burning in an inert atmosphere and in water solutions. Fire suppression is reached only upon dilution with water above 22:1.
Sources: en.wikipedia.org
== Applications in biomedical research == LifeAct peptides have been used as a universal marker for F-actin visualization in biomedical research. An experiment conducted by Sawant et al. utilized LifeAct GFP to visualize the migration of control border cells in the ovaries of Drosophila flies, in order to determine how cells move in terms of small and large collectives during development and cancer. Lifeact labels F-actin in border cells and adjacent follicle cells allowed for the detailed examination of border cell membranes and protrusions. Studies regarding the degradation of actin cytoskeleton due to aging relied on LifeAct for the analysis of cytoskeletal organization as a function of age. Transgenic lines that expressed the LifeAct in various tissues of C. elegans were primarily used for imaging.
Erythritol (, US: ) is an organic compound, the naturally occurring achiral meso four-carbon sugar alcohol (or polyol). It is the reduced form of either D- or L-erythrose and one of the two reduced forms of erythrulose. It is used as a food additive and sugar substitute. It is synthesized from corn using enzymes and fermentation. Its formula is C4H10O4, or HO(CH2)(CHOH)2(CH2)OH. Erythritol is 60–70% as sweet as table sugar. However, erythritol is almost completely noncaloric and does not affect blood sugar or cause tooth decay. Japanese companies pioneered the commercial development of erythritol as a sweetener in the 1990s.
Majority (about 70% to 80%) is converted to bicarbonate ions (HCO3–) by the enzyme carbonic anhydrase in the red blood cells, by the reaction: CO2 + H2O → H2CO3 → H+ + HCO3– 5–10% is dissolved in blood plasma 5–10% is bound to hemoglobin as carbamino compounds Hemoglobin, the main oxygen-carrying molecule in red blood cells, carries both oxygen and carbon dioxide. However, the CO2 bound to hemoglobin does not bind to the same site as oxygen. Instead, it combines with the N-terminal groups on the four globin chains. However, because of allosteric effects on the hemoglobin molecule, the binding of CO2 decreases the amount of oxygen that is bound for a given partial pressure of oxygen. This is known as the Haldane Effect, and is important in the transport of carbon dioxide from the tissues to the lungs. Conversely, a rise in the partial pressure of CO2 or a lower pH will cause offloading of oxygen from hemoglobin, which is known as the Bohr effect.
A descriptor which is applied to any substance or process which is being investigated for clinical use but either has not commenced, or has not completed, clinical trials. Examples: candidate vaccine, candidate formulation. Case report
Sources: en.wikipedia.org
No. Melanotan-2 is manufactured synthetically. The naturally occurring peptide in the same family is alpha-melanocyte-stimulating hormone, which the body produces as part of normal endocrine and neural signalling.
Both are synthetic analogues derived from the same parent hormone. Reference descriptions usually characterise afamelanotide as more selective for the MC1R subtype, whereas melanotan-2 is reported to interact with a wider range of melanocortin receptors.
Early studies explored melanocortin signalling and pigmentation, which later led to informal use of the label tanning peptide. That label is not a regulatory category and does not imply approved status for any purpose.
Purity is normally stated as an area percentage from high-performance liquid chromatography, for example ninety-five or ninety-eight percent. That figure describes the proportion of ultraviolet-absorbing material eluting as the main peak. It says nothing about water content, counterions, residual solvents or mass fraction of the peptide itself.