A practical reference on prohibited list: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
This page was last updated on 2026-07-25 and is reviewed periodically as new material appears.
Structurally, Melanotan-2 retains the core recognition motif of alpha-melanocyte-stimulating hormone while adding a lactam bridge that links two side chains and constrains the molecule into a ring. This modification lowers susceptibility to enzymatic degradation. The compound acts as an agonist at melanocortin receptors, particularly subtypes associated with melanin production. Because the same receptor family influences several physiological processes, researchers note that its activity is not confined to pigmentation alone. Receptor selectivity continues to be examined in published studies.
Melanotan-2 is a synthetic cyclic heptapeptide designed as an analogue of alpha-melanocyte-stimulating hormone, a naturally occurring peptide involved in pigmentation signalling. Its sequence incorporates modified residues that increase potency and extend biological activity relative to the native hormone. The compound binds receptors of the melanocortin family and is examined mainly in laboratory research. It does not occur naturally and exists only as a manufactured chemical entity produced by solid-phase synthesis.
Regulatory treatment varies by country. In the United States, melanotan-2 is not approved for any indication, and products marketed for human use fall outside the approved drug framework. Some other jurisdictions have placed it under prescription controls or listed it as a prohibited or restricted substance. Online listings frequently describe the material as a research chemical, a category that does not carry the same manufacturing and labelling requirements as approved medicines.
Solid peptide material is generally stable when kept cold and dry. Common practice is storage at -20 degrees Celsius or lower, with desiccant and protection from light. Repeated freeze-thaw cycles and exposure to moisture are associated with degradation, aggregation, or loss of material. Once dissolved, stability depends on solvent, concentration, and temperature, and solutions are usually treated as short-lived unless stability data support longer periods. Handling notes typically emphasise minimising time at ambient temperature.
| Property | Value | Notes |
|---|---|---|
| Molecular formula | C50H69N15O9 | Synthetic cyclic heptapeptide |
| Molecular mass | Approximately 1024 g/mol | Depends on counter-ion content |
| Appearance | White to off-white powder | Commonly supplied as a lyophilised solid |
| Solubility | Freely soluble in water | Also dissolves in common aqueous buffers |
| Typical storage | -20 degrees Celsius, desiccated | Protect from light and repeated freeze-thaw |
Receptor-binding studies classify melanotan II as a non-selective melanocortin agonist. It interacts with MC1R, MC3R, MC4R and MC5R, with reported affinities in the low nanomolar range and no strong subtype preference. Activation of MC1R on dermal melanocytes shifts pigment synthesis toward eumelanin, the dark polymer deposited in melanosomes and transferred to keratinocytes. Because the same peptide engages MC4R in the hypothalamus, it also appears in animal work on food intake and erectile response, which is why it is discussed in both pigment and metabolic research. Which receptor populations dominate after systemic exposure in humans is not fully established.
Published pharmacokinetic information is limited and comes mainly from small studies rather than registrational trials. Plasma half-life is usually described as short, on the order of tens of minutes, followed by rapid tissue distribution and clearance of the intact peptide. Metabolites and low concentrations of parent compound have been reported in urine, a detail relevant to anti-doping and forensic testing. Whether repeated exposure changes receptor sensitivity or clearance over time remains an open question. Values differ noticeably between analytical assays, so published numbers should be read as approximate rather than definitive.
Melanotan II is a synthetic cyclic heptapeptide with the sequence Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH2, corresponding to a molecular formula of C50H69N15O9 and a monoisotopic mass near 1024 daltons. It was designed as a structural analogue of alpha-melanocyte-stimulating hormone, a peptide hormone produced by cleavage of proopiomelanocortin. A lactam bridge between the aspartate and lysine side chains closes the ring, and the C-terminal amide removes a free carboxyl group. Both modifications increase resistance to enzymatic degradation compared with the linear parent hormone. Four substitutions distinguish it from afamelanotide, the linear analogue studied under the name melanotan I.
Regulatory treatment of this peptide varies by country. It holds no marketing authorization as a medicine in the United States, the European Union, or most other jurisdictions. Some countries classify products containing it as prescription-only or unlicensed medicines, which restricts lawful supply. Authorities have issued public notices warning that unregulated products may contain undeclared or incorrect ingredients. The molecule also appears on prohibited lists for competitive sport. These measures address supply oversight rather than any approved therapeutic role.
Published research on the compound remains limited. Much of the human data comes from small, early-stage studies rather than large controlled trials, and several questions about effects and variability between individuals remain open. Investigators have examined receptor activity, pigment pathways, and related physiological responses in laboratory and animal models. Findings from those models do not automatically translate to human outcomes. Reviews frequently note the scarcity of rigorous clinical evidence and call for better-characterized study material.
Melanotan II binds several melanocortin receptor subtypes rather than a single target. MC1R on melanocytes drives melanin synthesis, while MC3R and MC4R participate in energy balance, appetite, and sexual response pathways. This lack of selectivity explains why reported effects extend beyond skin darkening. Substitutions at positions four and seven, including norleucine and D-phenylalanine, increase potency and resistance to peptidases. Understanding which receptor mediates which effect remains an active area of investigation.
Published human data come mostly from small, short studies rather than large controlled trials. Reported outcomes include increased skin pigmentation and, in some reports, effects on appetite and libido, but sample sizes are small and follow-up is limited. Whether long-term use produces durable pigment changes or adverse effects is not established. Because products sold outside pharmacies are not standardized, the actual content of any given vial is often unknown. Independent testing of such material is uncommon.
Melanotan II is a synthetic cyclic heptapeptide analog derived from the core sequence of alpha-melanocyte-stimulating hormone. Researchers at the University of Arizona synthesized it during the 1980s while studying pigmentation and appetite signaling. The compound is not an approved medicine in any major jurisdiction and appears mainly in laboratory and research-chemical settings. Its structure incorporates a lactam bridge between side chains, which constrains the ring and slows enzymatic breakdown relative to the natural hormone.
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.
Reversed-phase high-performance liquid chromatography is the routine method for purity assessment. Peptides absorb near 214 nm because of the peptide bond, and a gradient of acetonitrile in water separates the intact peptide from deletion sequences, oxidised products, and earlier-eluting fragments at neutral pH. Electrospray ionisation mass spectrometry provides an orthogonal check: the measured mass must agree with the theoretical value. Amino acid analysis and peptide mapping confirm structure but are used less often. Reference standards remain scarce because the peptide is not described in any pharmacopoeia.
== Rankings and selectivity == U.S. News & World Report ranked the School of Medicine 74th (2022–23) in the Best Research category and 90th (2022–23) in the Primary Care category nationally. In 2020, the MD program received over 6,100 applications for 182 seats. The incoming class had an average GPA of 3.75 and MCAT score of 512, which is the 85th percentile nationally. Over 87.4% matriculants were NYS residents, the remaining 12.6% were "out of state".
=== Other uses and occurrences === Pyrolysis is used to turn organic materials into carbon for the purpose of carbon-14 dating. Pyrolysis liquids from slow pyrolysis of bark and hemp have been tested for their antifungal activity against wood decaying fungi, showing potential to substitute the current wood preservatives while further tests are still required. However, their ecotoxicity is very variable and while some are less toxic than current wood preservatives, other pyrolysis liquids have shown high ecotoxicity, what may cause detrimental effects in the environment. Pyrolysis of tobacco, paper, and additives, in cigarettes and other products, generates many volatile products (including nicotine, carbon monoxide, and tar) that are responsible for the aroma and negative health effects of smoking. Similar considerations apply to the smoking of marijuana and the burning of incense products and mosquito coils. Pyrolysis occurs during the incineration of trash, potentially generating volatiles that are toxic or contribute to air pollution if not completely burned. Laboratory or industrial equipment sometimes gets fouled by carbonaceous residues that result from coking, the pyrolysis of organic products that come into contact with hot surfaces.
=== Insecticide === Isolated myristicin has proven an effective insecticide against many agricultural pests, including Aedes aegypti mosquito larvae, Spilosoma obliqua (hairy caterpillars), Epilachna varivestis (Mexican bean beetles), Acyrthosiphon pisum (pea aphids), mites, and Drosophila melanogaster (fruit flies). Myristicin was shown to be an effective repellent, and to cause mortality via direct and systemic exposure. It also displayed a synergistic effect when administered to insects in combination with existing insecticides.
=== Electrochemical skin conductance === Electrochemical skin conductance (ESC) is an objective, quantitative, non-invasive method for the assessment of sudomotor function that utilizes chronoamperometry (the application of rectangular direct current (DC) pulses of varying voltage amplitudes) to electrically stimulate eccrine sweat glands, and reverse iontophoresis (the migration of electrolytes from the human sweat to the electrodes) for quantitative measurement of the resulting flow of Cl- ions. ESC can be measured with the use of a medical device called Sudoscan. A novel electrochemical model of the skin was devised, reproducing the behavior of chloride ions and the properties of their ion channel to develop a computational tool for measuring chloride ion flow through a sweat gland in response to an imposed voltage. In vitro electrochemical studies were then carried out in conventional three-electrode cells to identify the origin of currents measured upon the application of low voltage potentials with variable amplitudes to stainless steel electrodes applied to the skin during clinical tests. These studies also evaluated the influence of different parameters in sweat (e.g., urea, lactate) on the obtained currents. These studies formed the basis for the ESC methodology of measuring sudomotor function. The flow of Cl− ions in the sweat secreted from the activated sweat glands are captured by the anode. This process is repeated twice for the feet and twice for the hands with the right and left electrodes alternating as the anode and cathode.
Sickle cell disease exhibits characteristics of either homozygous hemoglobin S, also known as Hb S, or Hb S paired with another hemoglobin variant. In diagnosing patients with sickle cell, HbA2 is taken into account alongside a complete blood count, family history, and clinical data.
Sources: en.wikipedia.org
Due to their numerous sources indoors, concentrations of VOCs indoors are consistently higher (up to ten times higher) than outdoors. VOCs are emitted by thousands of indoor products. Examples include: paints, varnishes, waxes and lacquers, paint strippers, cleaning and personal care products, pesticides, building materials and furnishings, office equipment such as copiers and printers, correction fluids and carbonless copy paper, graphics and craft materials including glues and adhesives, permanent markers, and photographic solutions. Human activities such as cooking and cleaning can also emit VOCs. Cooking can release long-chain aldehydes and alkanes when oil is heated and terpenes can be released when spices are prepared and/or cooked. Cleaning products contain a range of VOCs, including monoterpenes, sesquiterpenes, alcohols and esters. Once released into the air, VOCs can undergo reactions with ozone and hydroxyl radicals to produce other VOCs, such as formaldehyde. Some VOCs are emitted directly indoors, and some are formed through the subsequent chemical reactions. The total concentration of all VOCs (TVOC) indoors can be up to five times higher than that of outdoor levels. New buildings experience particularly high levels of VOC off-gassing indoors because of the abundant new materials (building materials, fittings, surface coverings and treatments such as glues, paints and sealants) exposed to the indoor air, emitting multiple VOC gases.
The sequence of a gene can be altered in a number of ways. Gene mutations have varying effects on health depending on where they occur and whether they alter the function of essential proteins. Mutations in the structure of genes can be classified into several types.
Metroglas (Switzerland) manufactures electrochemical and optical sensors for laboratory and process analysis. Metrohm Process Analytics (Netherlands) develops and manufactures online analyzers for the process industry. Metrohm Autolab (Netherlands) develops modular electrochemical measuring instruments, especially for spectroelectrochemistry, corrosion, and battery research. Metrohm DropSens (Spain) produces tools for electrochemical analysis, especially screen-printed electrodes and portable electrochemical instruments. Innovative Photonic Solutions (USA) develops stabilized laser sources for Raman spectroscopy. Metrohm Spectro (USA) manufactures Raman instruments and components, including lasers and high-performance semiconductor diode light source systems. As of 2021, the company generated revenue of more than 400 million Swiss francs. As of 2024, Metrohm employs around 3,200 people worldwide, including approximately 700 at its headquarters in Herisau.
Watson was retrospectively ruled ineligible for the award by the commission, and the medal then awarded to the next-highest vote-getters, Richmond's Trent Cotchin and then-Hawthorn player Sam Mitchell (who had just been traded to the West Coast Eagles at the time), under the normal rules regarding ineligible players in Brownlow Medal counts. Watson had pre-empted the decision by announcing on 11 November 2016 that he would hand back the medal.
Sources: en.wikipedia.org
=== Closing equity gaps === Turner co-authored a paper in 2019 summarising the findings of a retrospective cohort study of New Zealand children (born 2006–2015), which identified that hospitalisation rates for infectious diseases since 1989 had increased disproportionately for Maori and Pacific children and those who were socioeconomically most deprived, but that those children who received the pneumococcal conjugate vaccine (PVC) between 2008 and 2014, were less likely to be hospitalized. The paper concludes that the use of PVC was associated with "reductions in ethnic and socioeconomic disparities in hospitalization". Turner co-authored another report on a research study that showed foreign-born migrant children living in New Zealand had an overall lower vaccination rate than NZ-born migrant and non-migrant children. It was acknowledged that there needed to be an improvement in the way such data were gathered, highlighting the importance of having "better national surveillance and migrant-specific data related to vaccination coverage to help uncover health inequities among children living in NZ and inform immunisation policy and practice". A follow-up paper on this research highlighted that to get a better understanding of migrant health, data must be disaggregated to locate hidden trends, provide information about subsets and make vulnerable groups more visible. Much of Turner's research and writing has been on the importance of people getting accurate information about immunisation, particularly to reassure parents that vaccines were safe.
The potential of epitaxial graphene on SiC for metrology has been shown since 2010, displaying quantum Hall resistance quantization accuracy of three parts per billion in monolayer epitaxial graphene. Over the years precisions of parts-per-trillion in the Hall resistance quantization and giant quantum Hall plateaus have been demonstrated. Developments in the encapsulation and doping of epitaxial graphene have led to the commercialization of epitaxial graphene quantum resistance standards. Novel uses for graphene continue to be researched and explored. One such use is in combination with water-based epoxy resins to produce anticorrosive coatings. The van der Waals nature of graphene and other two-dimensional (2D) materials also permits van der Waals heterostructures and integrated circuits based on Van der Waals integration of 2D materials. Graphene is utilized in detecting gasses and chemicals in environmental monitoring, developing highly sensitive biosensors for medical diagnostics, and creating flexible, wearable sensors for health monitoring. Graphene's transparency also enhances optical sensors, making them more effective in imaging and spectroscopy.
== Factors that influence results == Apart from the semen quality itself, there are various methodological factors that may influence the results, giving rise to inter-method variation. Compared to samples obtained from masturbation, semen samples from collection condoms have higher total sperm counts, sperm motility, and percentage of sperm with normal morphology. For this reason, they are believed to give more accurate results when used for semen analysis. If the results from a man's first sample are subfertile, they must be verified with at least two more analyses. At least two to four weeks must be allowed between each analysis. Results for a single man may have a large amount of natural variation over time, meaning a single sample may not be representative of a man's average semen characteristics. In addition, sperm physiologist Joanna Ellington believes that the stress of producing an ejaculate sample for examination, often in an unfamiliar setting and without any lubrication (most lubricants are somewhat harmful to sperm), may explain why men's first samples often show poor results while later samples show normal results. A man may prefer to produce his sample at home rather than at the clinic. The site of semen collection does not affect the results of a semen analysis. If produced at home, the sample should be kept as close to body temperature as possible, as exposure to cold or warm conditions can affect sperm motility.
Sources: en.wikipedia.org
It is a synthetic cyclic heptapeptide and an analogue of alpha-melanocyte-stimulating hormone. The molecule is produced by chemical synthesis rather than extracted from a biological source.
It is shorter than the native hormone and carries a cyclic constraint that improves stability. These changes raise receptor potency and slow breakdown relative to the naturally occurring peptide.
Published accounts date its development to the 1980s, when researchers were generating analogues of melanocyte-stimulating hormone. That work aimed to produce more stable compounds for studying pigmentation biology.
Laboratory confirmation typically combines retention time matching on a chromatographic system with mass measurement. A reference standard of known identity is needed for a meaningful comparison. Sequence-level techniques can add further confirmation.