Melanotan II raises a handful of sensible questions. This page answers them in order, starting with the fundamentals and moving to applications.
Reviewed 2026-06-21. Anything still debated is marked as such rather than presented as settled.
Pharmacologically, melanotan-2 behaves as a non-selective agonist across the melanocortin receptor family. Binding at MC1R on dermal melanocytes promotes eumelanin synthesis, which underlies the tanning response described in early human work. Activity at the centrally expressed MC4R receptor is associated with reported effects on appetite and erectile function. Because the peptide does not discriminate strongly among receptor subtypes, attributing any single observed effect to one receptor pathway is generally not possible without selective antagonists or receptor knockout models.
Research interest has centred on photoprotection and pigmentation, with a smaller body of work on appetite and sexual function. Published human data remain limited to small, frequently uncontrolled studies, and the compound has never received marketing approval from a national medicines regulator. Most laboratory work treats it as a pharmacological tool for probing melanocortin signalling in cell culture or animal models. Whether pigmentation changes observed in people translate into measurable protection against ultraviolet-induced DNA damage remains an open question.
Melanotan-2 is a synthetic cyclic heptapeptide designed as an analogue of alpha-melanocyte-stimulating hormone, the naturally occurring peptide involved in pigmentation signalling. Its sequence is conventionally written as Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH2, with a lactam bridge joining the aspartate side chain to the lysine side chain. The empirical formula is C50H69N15O9 and the monoisotopic mass lies near 1023.5 daltons. N-terminal acetylation and the D-configured phenylalanine both increase resistance to enzymatic breakdown compared with the parent hormone.
Reported observations after unregulated use include shifts in skin pigmentation and, in some accounts, unintended changes to moles and other lesions. Whether these outcomes are causally linked to the compound, and how often they occur, remain open questions because controlled data are scarce. The absence of standardised dosing and verified product purity complicates interpretation. Researchers have called for better surveillance and analytical characterisation of samples obtained outside regulated channels. Conclusions drawn from anecdotal evidence should be treated as provisional.
Melanotan-2 has not received marketing authorisation from major regulatory agencies for any therapeutic indication. Several jurisdictions classify it as a prescription-only medicine or a controlled substance when supplied for human use. Because approved products do not exist, material sold online usually sits outside pharmaceutical supply chains and formal quality oversight. Regulators have issued public notices describing the compound as unapproved. Enforcement varies, and the legal position differs between countries, which complicates any single general statement about its status.
| Property | Value | Notes |
|---|---|---|
| Common synonyms | Melanotan II; MT-II; N-acetyl-norleucyl-cyclo[Asp-His-D-Phe-Arg-Trp-Lys] amide | Naming follows peptide convention; the numeral distinguishes it from melanotan-1 |
| Molecular formula | C50H69N15O9 | Includes the lactam bridge; no counter-ion assumed |
| Monoisotopic mass | 1023.53 Da | Free base; salts and counter-ions shift the observed value |
| Appearance | White to off-white lyophilised powder | Batch-to-batch colour variation is not itself proof of impurity |
| Typical analytical method | RP-HPLC purity determination with ESI-MS identity confirmation | Retention time alone does not establish sequence identity |
Two structural changes distinguish the synthetic peptide from the natural hormone. A norleucine residue replaces methionine at one position, and a D-configured phenylalanine replaces the natural L-form at another. Both substitutions slow enzymatic breakdown, which extends the molecule's persistence relative to the parent hormone. The lactam bridge further constrains the backbone into a stable conformation. These features are standard design strategies in peptide chemistry and are not unique to this compound; they appear across many research peptides built for improved stability.
The compound was developed in the late 1980s and early 1990s by academic researchers investigating melanocortin signaling and pigmentation. Early work explored whether synthetic analogs could reproduce effects of the natural hormone under controlled conditions. The molecule never advanced through the full regulatory pathway required for approval as a medicine. From the mid-2000s onward it appeared in unregulated consumer markets, often distributed through informal channels. That gap between research origins and commercial availability shapes how the compound is discussed today.
Regulatory treatment varies by country. In the United States the peptide is not approved as a medicine, and products offered for human use may be treated as unapproved new drugs; some states also restrict sale. Australia, the United Kingdom, and European Union member states apply comparable restrictions to unapproved peptide products. Border agencies have seized shipments labelled as research chemicals. Classification may change over time, and the legal position for personal importation is not clearly settled in most published guidance.
Lyophilised melanotan-2 is supplied as a solid, which is more stable than a solution. The material is hygroscopic, so weighing is done quickly, in low humidity, with the container kept sealed. Reconstitution usually uses water for injection or bacteriostatic water, added down the wall of the vial to limit foaming. A reconstituted solution is held at 2 to 8 °C and kept away from light. Repeated freezing and thawing of the same vial is avoided because ice crystal formation and concentration effects degrade the peptide.
The compound was developed in the late 1980s and 1990s by academic researchers investigating photoprotection. The rationale held that stimulating melanin production might reduce ultraviolet damage to skin and lower skin cancer risk. Early work examined receptor binding, pigment response, and short-term tolerability in small studies. That program did not produce an approved drug, and formal development stalled after early-phase trials. Whether induced pigmentation confers meaningful photoprotection remains an open question.
Outside regulated medicine, melanotan II circulates through online vendors as a research chemical, often marketed for tanning. Products sold this way vary widely in purity, concentration, and labeling accuracy, and independent testing has documented discrepancies. Published reports describe both pigment effects and adverse reactions, including nausea, flushing, and darkening of existing moles. Long-term safety data are sparse, and no large controlled trial has established a risk profile. Questions about cumulative effects on melanocytes remain unresolved in the literature.
Identity testing for a cyclic peptide of this size usually relies on reversed-phase high-performance liquid chromatography coupled to mass spectrometry. The mass spectrum confirms molecular weight, while the chromatographic trace indicates the proportion of related impurities. Tandem mass spectrometry can provide sequence-level information when fragmentation data are compared against a reference standard. Nuclear magnetic resonance is sometimes used to confirm the lactam bridge, although it requires more material and greater operator expertise than routine chromatographic methods.
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.
=== Acid hydrolysis === Acid hydrolysates are produced from various edible protein sources, with soy, corn, wheat, and casein being the most common. For the production of aHVP, the proteins are hydrolyzed by cooking with a diluted (15–20%) hydrochloric acid, at a temperature between 90 and 120 °C for up to 8 hours. After cooling, the hydrolysate is neutralized with either sodium carbonate or sodium hydroxide to a pH of 5 to 6. During hydrolysis, extraneous polymeric material known as humin, which forms from the interaction of carbohydrate and protein fragments, is generated and subsequently removed by filtration and then further refined. The source of the raw material, concentration of the acid, the temperature of the reaction, the time of the reaction, and other factors can all affect the organoleptic properties of the final product. Activated carbon treatment can be employed to remove both flavor and color components, to the required specification. Following a final filtration, the aHVP may, depending upon the application, be fortified with additional flavoring components. Thereafter, the product can be stored as a liquid at 30–40% dry matter, or alternatively it may be spray dried or vacuum dried and further used as a food ingredient. One hundred pounds (45 kg) of material containing 60% protein will yield 100 pounds of aHVP, which contains approximately 40 pounds (18 kg) of salt. This salt gain occurs during the neutralization step.
Theodore Ryder (September 14, 1916 – March 8, 1993), often called Ted or Teddy Ryder, was, at the age of five, one of the first twelve people with diabetes in the world to be treated using insulin. When he died in 1993 at the age of 76, he became the world's first person to live 70 years with diabetes and probably the longest documented case of sustained insulin treatment in medical history. He was also the last survivor of the first twelve diabetes patients treated with insulin.
=== Marginal notes === Like that of all French municipalities, Parisian civil records have been updated over time. Since October 28, 1922, birth records have included the dates and places of birth of the parents. Marginal notes have gradually been added to birth records, including the dates and places of marriage and legitimations since the law of August 17, 1897, divorce information since March 10, 1932, and the dates and places of death since the ordinance of March 29, 1945.
The two opposing glutamates add and subtract protons from C1 and C2 and their respective oxygens, O1 and O2. The first half of the reaction transfers a proton from C1 to O2, whereas the second half transfers a proton from O1 to C2. The former reaction may be carried out by either of the opposing glutamates, depending on the initial chirality of C1 in the hemithioacetal substrate; however, the second half is stereospecific and is carried out by only one of the opposing glutamates. It is worthy to note that the first theoretically confirmed mechanism for the R-substrate of glyoxalase one published recently. The catalytic mechanism of Glyoxalase has been studied by density functional theory, molecular dynamics simulations and hybrid QM/MM methods. The reason for the special specificity of the enzyme (it accepts both enantiomers of its chiral substrate but converts them to the same enantiomer of the product) is the higher basicity and flexibility of one of the active site glutamates (Glu172).
Sofpironium bromide, sold under the brand names Ecclock and Sofdra among others, is a medication used to treat hyperhidrosis (excessive sweating). Sofpironium bromide is an anticholinergic agent that is applied to the skin. It was approved for medical use in Japan in 2020, and in the United States in June 2024.
Sources: en.wikipedia.org
Historic England. "Bawdsey Chain Home Station (1309533)". Research records (formerly PastScape). Retrieved 9 October 2015. Historic England. "Great Bromley Chain Home Station (1476819)". Research records (formerly PastScape). Retrieved 9 October 2015. Historic England. "Canewdon Chain Home Station (1412472)". Research records (formerly PastScape). Retrieved 9 October 2015. Historic England. "Dunkirk Chain Home Station (1377189)". Research records (formerly PastScape). Retrieved 9 October 2015. Historic England. "High Street Chain Home Station (1476863)". Research records (formerly PastScape). Retrieved 9 October 2015. Historic England. "Pevensey Chain Home Station (1476551)". Research records (formerly PastScape). Retrieved 9 October 2015. Historic England. "Rye Chain Home Station (1476520)". Research records (formerly PastScape). Retrieved 9 October 2015. Historic England. "Ventnor Chain Home Station (1306901)". Research records (formerly PastScape). Retrieved 9 October 2015. Early Radar Memories Archived 2 September 2010 at the Wayback Machine Memories of Sgt. Jean Semple, one of Britain's pioneer radar operators RAF Bawdsey Chain Home Radar Station at Subterranean Britain RAF Radar Museum RAF High Street picture Life at Darsham Deprecated link archived 19 April 2013 at archive.today – BBC Great Baddow Chain Home Mast & Radar Anniversary Chain Home Radar – A Personal Reminiscence, M Scanlan, GEC Review, 1993 Early radar development in the UK at purbeckradar.co.uk 60 (Signals) Group, Fighter Command Archived 16 November 2017 at the Wayback Machine (pdf)
=== English === Order, Sons of St. George - Organized after the Civil War by Englishmen in the anthracite coal-mining region of Pennsylvania to counter the Molly Maguires. The organization "took permanent shape" at Scranton in 1871. Membership was open to "Englishmen, their sons, and grandsons, wherever born". Beneficiary membership was limited to those between 18 and 50; those over 50 were allowed honorary membership. The Order required belief in a Supreme Being, reverence for the Holy Bible, and loyalty to one's adopted country. By 1896 the order had about 35,000 members in the United States, Canada, and Hawaii. Ritual based on the legend of St. George included a "language of words, signs and grips" that the member learned upon initiation which could identify him to other members of the order. The Orders emblem was St. George conquering the dragon. The system of sick benefits varied by the lodge and the inclination of members. There was also a funeral benefit for members and their wives and a benevolent fund for brethren and "any worthy Englishman in distress". Some lodges also provided physicians and medicine for sick members. There was also a female auxiliary, the Daughters of St. George, but it was not officially recognized by the Supreme Lodge. In 1923 the Order was accused of promoting pro-British propaganda in textbooks used in New York by a representative of Mayor John Francis Hylan. Sons of England Benevolent Society - Fraternal order for Canadians of English descent.
The surgeon replaces missing parts with tissue of like quality and quantity; nasal lining with mucosa, cartilage with cartilage, bone with bone, and skin with skin that best match the native skin color and skin texture of the damaged nasal subunit. For such surgical repairs, skin flaps are preferable to skin grafts, because skin flaps generally are the superior remedy for matching the color and the texture of nasal skin, better resist tissue contracture, and provide better vascularisation of the nasal skeleton; thus, when there is sufficient skin to allow tissue harvesting, nasal skin is the best source of nasal skin. Furthermore, despite its notable scarring propensity, the nasal skin flap is the prime consideration for nasal reconstruction, because of its greater verisimilitude. The most effective nasal reconstruction for repairing a defect (wound) of the nasal skin, is to re-create the entire nasal subunit; thus, the wound is enlarged to comprehend the entire nasal subunit. Technically, this surgical principle permits laying the scars in the topographic transition zone(s) between and among adjacent aesthetic subunits, which avoids juxtaposing two different types of skin in the same aesthetic subunit, where the differences of color and texture might prove too noticeable, even when reconstructing a nose with skin flaps. Nonetheless, in the final stage of nasal reconstruction—replicating the "normal nose" anatomy by subcutaneous sculpting, the surgeon does have technical allowance to revise the scars, and render them (more) inconspicuous.
=== Timeline === Mixue Ice Cream & Tea began in 1997 when Zhang Hongchao opened the first location under the Mixue name. After six relocations, the first successful Mixue Ice Cream & Tea store opened in 2003. Around 2005 or 2006, the company introduced soft serve ice cream at the price of just CN¥1, this quickly became a best-seller and its first signature product. In 2007, Mixue began franchising after opening a new ice cream shop. The following year, it established Mixue Ice Cream & Tea Trading Co., Ltd. to manage its growing network of franchises. Mixue took its first step outside of China on September 5, 2018, with a store opening in Hanoi, Vietnam. Later that year, in November, it launched a new brand mascot, Snow King. Between May 24 and 26, 2019, the company hosted an "ice cream music festival" at Opalala Water Park in Zhengzhou, drawing over 30,000 visitors. On June 24, 2020, Mixue celebrated the opening of its 10,000th store in Yuanyang County, Henan, Xinxiang. The same year, it expanded into Indonesia with a branch in Cihampelas Walk, Bandung. In 2022, Mixue made significant purchases of over 9,000 tonnes (8,900 long tons; 9,900 short tons) of tea, benefiting around 50,000 tea farmers, while also supporting over 11,000 franchisees and generating more than 500,000 jobs. It launched a CN¥6.5 million scholarship program across five universities in Henan and expanded into additional Southeast Asian markets, opening stores in Singapore, Thailand, Cambodia, Philippines, Laos, and Myanmar. By the end of 2022, Mixue had also entered South Korea and Japan.
Sources: en.wikipedia.org
=== Benzene toxicity === Benzene poisoning can increase risk of hematological cancers and other disorders. The mechanism of benzene metabolism and how it affects toxicity has not been completely understood. A general observation is that there is high variation in the extent of damage due to benzene poisoning. A possible explanation is the accumulation of phenols and hydroquinone in the target organ—the bone marrow—and subsequent oxidation of these metabolites to reactive quinone metabolites via a number of possible pathways. A case-control study conducted in China showed that patients with two copies of the NQO1 C609T (NQO1*2 polymorphism) mutation had a 7.6-fold increased risk of benzene poisoning compared to those who carried one or two wild-type NQO1 alleles.
=== Cryo-EM Facility === The cryo-EM facility at the Life Sciences Institute offers a wide range of advanced microscopes and technologies for cryo-electron microscopy, cryo-electron tomography, and correlative light and electron microscopy (CLEM).
In a study on dinosterol side chain synthesis in the marine heterotrophic dinoflagellate, Crypthecodinium cohnii, the dinoflagellates were cultured with methionine-[CD3]. GC-MS analysis revealed that the C-23 methyl group contained three deuterium atoms that were introduced by transmethylation from methionine. The C-24 methyl group contained only two deuterium atoms, consistent with a 24-methylenesterol intermediate, which is reduced to the resulting 24-methyl side chain. This mechanism has been previously reported in fungi, a chrysophyte alga and a diatom. Importantly, no deuterium was incorporated into cholesterol or cholesta-5,7-dien-3β-ol, which are the major 4-methyl-sterols in Crypthecodinium cohnii. A suggested biosynthetic mechanism for side chain alkylations at C-23 and C-24 in dinosterol has been proposed.
Dr. Gian Parkash Gopal. Founder, Oxford Hindu Temple and Community Centre Project. For services to the Hindu Community and to Multi-Faith Cohesion in Oxfordshire. Elizabeth Jane Gorb. Director of Apprenticeships, Manchester Metropolitan University. For services to Education and Skills. Permjit Gosal (Pam Gosal), MSP. Member of the Scottish Parliament for West Scotland. For services to Business, to Racial Equality and to Charity in Milton Keynes. David James Connelly Graham. National Director, Care Leavers Association. For services to Care Leavers. Sarah Jane Vandevelde Graham. Founder, Hilltops Ukrainian Support Community. For services to Ukrainian Refugees. The Reverend Canon Terence Kevin Declan Graham, DL. Rector, St Bartholomew's Church, Belfast. For services to the Reserve Forces and to the community in Belfast. Julie Grant. Deputy Director, News and Digital, Scottish Government. For services to Scotland on the Demise of Her Majesty Queen Elizabeth II. Dr. Simon Jonathon Grant. Technical Director, Thomas Swan. For services to Diversity in the Chemical Industry. Belinda Elizabeth Gray. Founder, Art for Cure. For services to Breast Cancer Charities. Julie Heather Gray. Founder, Adventure Activities for All Abilities. For services to Children with Impairments in Nottinghamshire. Neil Jonathan Greenwood. Executive Director, Finance and Corporate Services, Natural History Museum. For services to Museums. Robert Terence Grey. Lately Boxing Gym Owner and Trainer, Gwent Amateur Boxing Club. For services to Amateur Boxing in Swansea. Dr. John Michael Grimshaw.
In physics and chemistry, binding energy is the smallest amount of energy required to remove a particle from a system of particles or to disassemble a system of particles into individual parts. In the former meaning the term is predominantly used in condensed matter physics, atomic physics, and chemistry, whereas in nuclear physics the term separation energy is used. A bound system is typically at a lower energy level than its unbound constituents. According to relativity theory, a ΔE decrease in the total energy of a system is accompanied by a decrease Δm in the total mass, where Δmc2 = ΔE.
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It is a synthetic cyclic heptapeptide analogue of alpha-melanocyte-stimulating hormone, containing seven amino acids with a lactam ring and a D-configured phenylalanine residue. It is supplied as a lyophilised powder for laboratory research.
The natural hormone is a linear tridecapeptide that is rapidly degraded in circulation. Melanotan-2 is shortened, cyclised, N-terminally acetylated, and carries a D-amino acid substitution, all of which slow enzymatic breakdown.
No national medicines regulator has approved melanotan-2 for therapeutic or cosmetic use. In several jurisdictions it is treated as an unapproved prescription medicine, and its legal classification differs from country to country.
Major regulatory agencies have not approved it for any indication. Some countries permit it only under prescription frameworks, while others classify it as a controlled substance.