research chemical is one of those subjects where the details matter more than the headlines. This page pulls together the background, the mechanisms, and the practical points readers ask about most.
Last reviewed on 2025-09-04. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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.
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.
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.
| Property | Value | Notes |
|---|---|---|
| Lyophilised storage | −20 °C, dry, protected from light | Vials are sealed and allowed to reach room temperature before opening |
| Reconstituted storage | 2 to 8 °C, protected from light | Short-term holding; avoid repeated freeze-thaw cycles |
| Reconstitution solvent | Water for injection or bacteriostatic water | Added slowly along the vial wall to reduce foaming and shear |
| Purity measurement | RP-HPLC with area normalisation | Acetonitrile-water gradient monitored at roughly 214 nm |
| Identity confirmation | Electrospray ionisation mass spectrometry | Observed mass compared against the calculated peptide mass |
Melanotan-2 appears on the World Anti-Doping Agency prohibited list within the peptide hormone class, and several national regulators treat it as an unapproved prescription substance. Some countries restrict importation or sale for personal use. Because the compound is widely traded as a research chemical, the practical legal picture differs between jurisdictions and shifts over time. Human safety data covering long periods are limited, and whether repeated pigmentation changes carry any lasting risk to melanocytes remains an open question.
Freeze-dried melanotan-2 is normally kept as a desiccated powder at minus twenty degrees Celsius or lower, shielded from light and moisture. Peptides of this size degrade through hydrolysis, oxidation and deamidation, and each pathway accelerates as temperature and water activity rise. Repeated freeze-thaw cycles promote aggregation and loss of material, so aliquoting a stock solution before freezing is standard laboratory practice. Once dissolved, the solution is markedly less stable than the powder. In laboratory work, solutions are generally refrigerated and used within days rather than kept for months.
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.
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.
Identity and purity are assessed with chromatographic and mass spectrometric techniques. Reversed-phase high-performance liquid chromatography separates the target peptide from related impurities and degradation products, and the resulting retention time is compared against a reference standard. Mass spectrometry, often coupled to liquid chromatography, confirms molecular mass. Amino acid analysis or peptide mapping can provide additional sequence-level confirmation when required. Results are only as reliable as the reference materials used alongside them.
Afonsoconus Tucker & Tenorio, 2013: synonym of Conus (Afonsoconus) Tucker & Tenorio, 2013 represented as Conus Linnaeus, 1758 Africonus Petuch, 1975: synonym of Conus (Lautoconus) Monterosato, 1923 represented as Conus Linnaeus, 1758 Arubaconus Petuch, 2013: synonym of Conus (Ductoconus) da Motta, 1991 represented as Conus Linnaeus, 1758 Asprella Schaufuss, 1869: synonym of Conus (Asprella) Schaufuss, 1869 represented as Conus Linnaeus, 1758 Atlanticonus Petuch & Sargent, 2012: synonym of Conus (Atlanticonus) Petuch & Sargent, 2012 represented as Conus Linnaeus, 1758 Attenuiconus Petuch, 2013: synonym of Conus (Attenuiconus) Petuch, 2013 represented as Conus Linnaeus, 1758 Austroconus Tucker & Tenorio, 2009 synonym of Conus (Austroconus) Tucker & Tenorio, 2009 represented as Conus Linnaeus, 1758 Bathyconus Tucker & Tenorio, 2009: synonym of Conasprella (Fusiconus) Thiele, 1929, represented as Conasprella Thiele, 1929 Bermudaconus Petuch, 2013: synonym of Conus (Bermudaconus) Petuch, 2013 represented as Conus Linnaeus, 1758 Boucheticonus Tucker & Tenorio, 2013: synonym of Conasprella (Boucheticonus) Tucker & Tenorio, 2013 represented as Conasprella Thiele, 1929 Brasiliconus Petuch, 2013: synonym of Conus (Brasiliconus) Petuch, 2013 represented as Conus Linnaeus, 1758 Calamiconus Tucker & Tenorio, 2009: synonym of Conus (Lividoconus) Wils, 1970 represented as Conus Linnaeus, 1758 Calibanus da Motta, 1991: synonym of Conus (Calibanus) da Motta, 1991 represented as Conus Linnaeus, 1758 Cariboconus Petuch, 2003: synonym of Conus (Dauciconus) Cotton, 1945 represented as Conus Linnaeus, 1758 Californiconus Tucker & Tenorio, 2009 Chelyconus Mörch, 1852: synonym of Conus (Chelyconus) Mörch, 1852 represented as Conus Linnaeus, 1758 Cleobula Iredale, 1930: synonym of Dendroconus Swainson, 1840 Coltroconus Petuch, 2013: synonym of Conasprella (Coltroconus) Petuch, 2013 represented as Conasprella Thiele, 1929 Conasprella Thiele, 1929: accepted name Conasprelloides Tucker & Tenorio, 2009: synonym of Conus (Dauciconus) Cotton, 1945 represented as Conus Linnaeus, 1758 † Conilithes Swainson, 1840 Continuconus Tucker & Tenorio, 2013 Conus Linnaeus, 1758: accepted name Cornutoconus Suzuki, 1972: synonym of Taranteconus Azuma, 1972 Coronaxis Swainson, 1840: synonym of Conus (Conus) Linnaeus, 1758 represented as Conus Linnaeus, 1758 Cucullus Röding, 1798: synonym of Conus (Conus) Linnaeus, 1758 represented as Conus Linnaeus, 1758 Cylinder Montfort, 1810: synonym of Conus (Cylinder) Montfort, 1810 represented as Conus Linnaeus, 1758 Cylindrella Swainson, 1840: synonym of Asprella Schaufuss, 1869synonym of Conus (Asprella) Schaufuss, 1869 represented as Conus Linnaeus, 1758 Cylindrus Batsch, 1789: synonym of Cylinder Montfort, 1810synonym of Conus (Cylinder) Montfort, 1810 represented as Conus Linnaeus, 1758 Dalliconus Tucker & Tenorio, 2009: synonym of Conasprella (Dalliconus) Tucker & Tenorio, 2009 synonym of Conasprella Thiele, 1929 Darioconus Iredale, 1930: synonym of Conus (Darioconus) Iredale, 1930 represented as Conus Linnaeus, 1758 Dauciconus Cotton, 1945: synonym of Conus (Dauciconus) Cotton, 1945 represented as Conus Linnaeus, 1758 Dendroconus Swainson, 1840: synonym of Conus (Dendroconus) Swainson, 1840 represented as Conus Linnaeus, 1758 Ductoconus da Motta, 1991: synonym of Conus (Ductoconus) da Motta, 1991 represented as Conus Linnaeus, 1758 Duodenticonus Tucker & Tenorio, 2013: synonym of Conasprella (Conasprella) Thiele, 1929 represented as Conasprella Thiele, 1929 Dyraspis Iredale, 1949: synonym of Conus (Virroconus) Iredale, 1930 represented as Conus Linnaeus, 1758 Elisaconus Tucker & Tenorio, 2013: synonym of Conus (Elisaconus) Tucker & Tenorio, 2013 represented as Conus Linnaeus, 1758 Embrikena Iredale, 1937: synonym of Conus (Embrikena) Iredale, 1937 represented as Conus Linnaeus, 1758 Endemoconus Iredale, 1931: synonym of Conasprella (Endemoconus) Iredale, 1931 represented as Conasprella Thiele, 1929 Eremiconus Tucker & Tenorio, 2009: synonym of Conus (Eremiconus) Tucker & Tenorio, 2009 represented as Conus Linnaeus, 1758 Erythroconus da Motta, 1991: synonym of Conus (Darioconus) Iredale, 1930 represented as Conus Linnaeus, 1758 Eugeniconus da Motta, 1991: synonym of Conus (Eugeniconus) da Motta, 1991 represented as Conus Linnaeus, 1758 Floraconus Iredale, 1930: synonym of Conus (Floraconus) Iredale, 1930 represented as Conus Linnaeus, 1758 Fraterconus Tucker & Tenorio, 2013: synonym of Conus (Fraterconus) Tucker & Tenorio, 2013 represented as Conus Linnaeus, 1758 Fulgiconus da Motta, 1991: synonym of Conus (Phasmoconus) Mörch, 1852 represented as Conus Linnaeus, 1758 Fumiconus da Motta, 1991: synonym of Conasprella (Fusiconus) da Motta, 1991 represented as Conasprella Thiele, 1929 Fusiconus da Motta, 1991: synonym of Conasprella (Fusiconus) da Motta, 1991 represented as Conasprella Thiele, 1929 Gastridium Modeer, 1793: synonym of Conus (Gastridium) Modeer, 1793 represented as Conus Linnaeus, 1758 Genuanoconus Tucker & Tenorio, 2009: synonym of Conus (Kalloconus) da Motta, 1991 represented as Conus Linnaeus, 1758 Gladioconus Tucker & Tenorio, 2009: synonym of Conus (Monteiroconus) da Motta, 1991 represented as Conus Linnaeus, 1758 Globiconus Tucker & Tenorio, 2009: synonym of Conasprella (Ximeniconus) Emerson & Old, 1962 represented as Conasprella Thiele, 1929 Gradiconus da Motta, 1991: synonym of Conus (Dauciconus) Cotton, 1945 represented as Conus Linnaeus, 1758 Graphiconus da Motta, 1991: synonym of Conus (Phasmoconus) Mörch, 1852 represented as Conus Linnaeus, 1758 Harmoniconus da Motta, 1991: synonym of Conus (Harmoniconus) da Motta, 1991 represented as Conus Linnaeus, 1758 Hermes Montfort, 1810: synonym of Conus (Hermes) Montfort, 1810 represented as Conus Linnaeus, 1758 Heroconus da Motta, 1991: synonym of Conus (Pionoconus) Mörch, 1852 represented as Conus Linnaeus, 1758 Isoconus Tucker & Tenorio, 2013: synonym of Conus (Splinoconus) da Motta, 1991 represented as Conus Linnaeus, 1758 Jaspidiconus Petuch, 2004: synonym of Conasprella (Ximeniconus) Emerson & Old, 1962 represented as Conasprella Thiele, 1929 Kalloconus da Motta, 1991: synonym of Conus (Kalloconus) da Motta, 1991 represented as Conus Linnaeus, 1758 Kellyconus Petuch, 2013: synonym of Conus (Kellyconus) Petuch, 2013 represented as Conus Linnaeus, 1758 Kenyonia Brazier, 1896: genus incertae sedis Kermasprella Powell, 1958: synonym of Conasprella (Endemoconus) Iredale, 1931 represented as Conasprella Thiele, 1929 Ketyconus da Motta, 1991: synonym of Conus (Floraconus) Iredale, 1930 represented as Conus Linnaeus, 1758 Kioconus da Motta, 1991: synonym of Conus (Splinoconus) da Motta, 1991 represented as Conus Linnaeus, 1758 Klemaeconus Tucker & Tenorio, 2013: synonym of Conus (Klemaeconus) Tucker & Tenorio, 2013 represented as Conus Linnaeus, 1758 Kohniconus Tucker & Tenorio, 2009: synonym of Conasprella (Kohniconus) Tucker & Tenorio, 2009 represented as Conasprella Thiele, 1929 Kurodaconus Shikama & Habe, 1968: synonym of Conus (Turriconus) Shikama & Habe, 1968 represented as Conus Linnaeus, 1758 Lamniconus da Motta, 1991: synonym of Conus (Lamniconus) da Motta, 1991 represented as Conus Linnaeus, 1758 Lautoconus Monterosato, 1923: synonym of Conus (Lautoconus) Monterosato, 1923 represented as Conus Linnaeus, 1758 Leporiconus Iredale, 1930: synonym of Conus (Leporiconus) Iredale, 1930 represented as Conus Linnaeus, 1758 Leptoconus Swainson, 1840: synonym of Conus (Leptoconus) Swainson, 1840 represented as Conus Linnaeus, 1758 Lilliconus Raybaudi Massilia, 1994: synonym of Conasprella (Lilliconus) G. Raybaudi Massilia, 1994 represented as Conasprella Thiele, 1929 Lindaconus Petuch, 2002: synonym of Conus (Lindaconus) Petuch, 2002 represented as Conus Linnaeus, 1758 Lithoconus Mörch, 1852: synonym of Conus (Lithoconus) Mörch, 1852 represented as Conus Linnaeus, 1758 Lividoconus Wils, 1970: synonym of Conus (Lividoconus) Wils, 1970 represented as Conus Linnaeus, 1758 Lizaconus da Motta, 1991synonym of Profundiconus Kuroda, 1956 Magelliconus da Motta, 1991: synonym of Conus (Dauciconus) Cotton, 1945 represented as Conus Linnaeus, 1758 Malagasyconus Monnier & Tenorio, 2015 Mamiconus Cotton & Godfrey, 1932: synonym of Endemoconus Iredale, 1931synonym of Conasprella (Endemoconus) Iredale, 1931 represented as Conasprella Thiele, 1929 Miliariconus Tucker & Tenorio, 2009: synonym of Conus (Virroconus) Iredale, 1930 represented as Conus Linnaeus, 1758 Mitraconus Tucker & Tenorio, 2013: synonym of Conus (Turriconus) Shikama & Habe, 1968 represented as Conus Linnaeus, 1758 Monteiroconus da Motta, 1991: synonym of Conus (Monteiroconus) da Motta, 1991 represented as Conus Linnaeus, 1758 Nataliconus Tucker & Tenorio, 2009: synonym of Conus (Leptoconus) Swainson, 1840 represented as Conus Linnaeus, 1758 Nimboconus Tucker & Tenorio, 2013: synonym of Conus (Phasmoconus) Mörch, 1852 represented as Conus Linnaeus, 1758 Nitidoconus Tucker & Tenorio, 2013: synonym of Conus (Splinoconus) da Motta, 1991 represented as Conus Linnaeus, 1758 Ongoconus da Motta, 1991: synonym of Conus (Splinoconus) da Motta, 1991 represented as Conus Linnaeus, 1758 Papyriconus Tucker & Tenorio, 2013: synonym of Conus (Papyriconus) Tucker & Tenorio, 2013 represented as Conus Linnaeus, 1758 Parviconus Cotton & Godfrey, 1932: synonym of Conasprella (Parviconus) Cotton & Godfrey, 1932 represented as Conasprella Thiele, 1929 Perplexiconus Tucker & Tenorio, 2009: synonym of Conasprella (Ximeniconus) Emerson & Old, 1962 represented as Conasprella Thiele, 1929 Phasmoconus Mörch, 1852: synonym of Conus (Phasmoconus) Mörch, 1852 represented as Conus Linnaeus, 1758 Pionoconus Mörch, 1852: synonym of Conus (Pionoconus) Mörch, 1852 represented as Conus Linnaeus, 1758 Plicaustraconus Moolenbeek, 2008: synonym of Conus (Plicaustraconus) Moolenbeek, 2008 represented as Conus Linnaeus, 1758 Poremskiconus Petuch, 2013: synonym of Conus (Dauciconus) Cotton, 1945 represented as Conus Linnaeus, 1758 Profundiconus Kuroda, 1956: accepted name Protoconus da Motta, 1991: synonym of Tenorioconus Petuch & Drolshagen, 2011 Protostrioconus Tucker & Tenorio, 2009: synonym of Conus (Gastridium) Modeer, 1793 represented as Conus Linnaeus, 1758 Pseudoconorbis Tucker & Tenorio, 2009: synonym of Conasprella (Pseudoconorbis) Tucker & Tenorio, 2009, represented as Conasprella Thiele, 1929 Pseudohermes Tucker & Tenorio, 2013: synonym of Conus (Virgiconus) Cotton, 1945 represented as Conus Linnaeus, 1758 Pseudolilliconus Tucker & Tenorio, 2009: synonym of Conus (Pseudolilliconus) Tucker & Tenorio, 2009 represented as Conus Linnaeus, 1758 Pseudonoduloconus Tucker & Tenorio, 2009: synonym of Conus (Pseudonoduloconus) Tucker & Tenorio, 2009 represented as Conus Linnaeus, 1758 Pseudopterygia Tucker & Tenorio, 2013: synonym of Conus (Pseudopterygia) Tucker & Tenorio, 2013 represented as Conus Linnaeus, 1758 Puncticulis Swainson, 1840: synonym of Conus (Puncticulis) Swainson, 1840 represented as Conus Linnaeus, 1758 Purpuriconus da Motta, 1991: synonym of Conus (Dauciconus) Cotton, 1945 represented as Conus Linnaeus, 1758 Pygmaeconus Puillandre & Tenorio, 2017 Pyruconus Olsson, 1967: synonym of Conus (Pyruconus) Olsson, 1967 represented as Conus Linnaeus, 1758 Quasiconus Tucker & Tenorio, 2009: synonym of Conus (Quasiconus) Tucker & Tenorio, 2009 represented as Conus Linnaeus, 1758 Regiconus Iredale, 1930: synonym of Conus (Darioconus) Iredale, 1930 represented as Conus Linnaeus, 1758 Rhizoconus Mörch, 1852: synonym of Conus (Rhizoconus) Mörch, 1852 represented as Conus Linnaeus, 1758 Rhombiconus Tucker & Tenorio, 2009: synonym of Conus (Stephanoconus) Mörch, 1852 represented as Conus Linnaeus, 1758 Rhombus Montfort, 1810: synonym of Rhombiconus Tucker & Tenorio, 2009, synonym of Conus (Stephanoconus) Mörch, 1852 represented as Conus Linnaeus, 1758 Rolaniconus Tucker & Tenorio, 2009: synonym of Conus (Strategoconus) da Motta, 1991 represented as Conus Linnaeus, 1758 Rollus Montfort, 1810 :synonym of Conus (Gastridium) Modeer, 1793 represented as Conus Linnaeus, 1758 Rubroconus Tucker & Tenorio, 2013: synonym of Conus (Rubroconus) Tucker & Tenorio, 2013 represented as Conus Linnaeus, 1758 Sandericonus Petuch, 2013: synonym of Conus (Sandericonus) Petuch, 2013 represented as Conus Linnaeus, 1758 Sciteconus da Motta, 1991: synonym of Conus (Sciteconus) da Motta, 1991 represented as Conus Linnaeus, 1758 Seminoleconus Petuch, 2003: synonym of Conus (Stephanoconus) Mörch, 1852 represented as Conus Linnaeus, 1758 Socioconus da Motta, 1991: synonym of Conus (Pionoconus) Mörch, 1852 represented as Conus Linnaeus, 1758 Splinoconus da Motta, 1991: synonym of Conus (Splinoconus) da Motta, 1991 represented as Conus Linnaeus, 1758 Spuriconus Petuch, 2003: synonym of Conus (Lindaconus) Petuch, 2002 represented as Conus Linnaeus, 1758 Stellaconus Tucker & Tenorio, 2009: synonym of Conus (Splinoconus) da Motta, 1991 represented as Conus Linnaeus, 1758 Stephanoconus Mörch, 1852: synonym of Conus (Stephanoconus) Mörch, 1852 represented as Conus Linnaeus, 1758 Strategoconus da Motta, 1991: synonym of Conus (Strategoconus) da Motta, 1991 represented as Conus Linnaeus, 1758 Strioconus Thiele, 1929: synonym of Pionoconus Mörch, 1852, synonym of Conus (Pionoconus) Mörch, 1852 represented as Conus Linnaeus, 1758 Sulciconus Bielz, 1869: synonym of Asprella Schaufuss, 1869, synonym of Conus (Asprella) Schaufuss, 1869 represented as Conus Linnaeus, 1758 Taranteconus Azuma, 1972: synonym of Conus (Stephanoconus) Mörch, 1852 represented as Conus Linnaeus, 1758 Tenorioconus Petuch & Drolshagen, 2011: synonym of Conus (Stephanoconus) Mörch, 1852 represented as Conus Linnaeus, 1758 Tesselliconus da Motta, 1991: synonym of Conus (Tesselliconus) da Motta, 1991 represented as Conus Linnaeus, 1758 Textilia Swainson, 1840: synonym of Conus (Textilia) Swainson, 1840 represented Conus Linnaeus, 1758 Thalassiconus Tucker & Tenorio, 2013: synonym of Calibanus da Motta, 1991, synonym of Conus (Calibanus) da Motta, 1991 represented as Conus Linnaeus, 1758 Theliconus Swainson, 1840: synonym of Hermes Montfort, 1810, synonym of Conus (Hermes) Montfort, 1810 represented as Conus Linnaeus, 1758 Thoraconus da Motta, 1991: synonym of Fulgiconus da Motta, 1991, synonym of Conus (Phasmoconus) Mörch, 1852 represented as Conus Linnaeus, 1758 Trovaoconus Tucker & Tenorio, 2009, synonym of Conus (Kalloconus) da Motta, 1991 represented as Conus Linnaeus, 1758 Tuckericonus Petuch, 2013: synonym of Conus (Dauciconus) Cotton, 1945 represented as Conus Linnaeus, 1758 Tuliparia Swainson, 1840: synonym of Gastridium Modeer, 1793, synonym of Conus (Gastridium) Modeer, 1793 represented as Conus Linnaeus, 1758 Turriconus Shikama & Habe, 1968, synonym of Conus (Turriconus) Shikama & Habe, 1968 represented as Conus Linnaeus, 1758 Utriculus Schumacher, 1817: synonym of Gastridium Modeer, 1793, synonym of Conus (Gastridium) Modeer, 1793 represented as Conus Linnaeus, 1758 Varioconus da Motta, 1991: synonym of Conus (Lautoconus) Monterosato, 1923 represented as Conus Linnaeus, 1758 Viminiconus Tucker & Tenorio, 2009: synonym of Conasprella (Fusiconus) da Motta, 1991 represented as Conasprella Thiele, 1929 Virgiconus Cotton, 1945: synonym of Conus (Virgiconus) Cotton, 1945 represented as Conus Linnaeus, 1758 Virroconus Iredale, 1930: synonym of Conus (Virroconus) Iredale, 1930 represented as Conus Linnaeus, 1758 Vituliconus da Motta, 1991: synonym of Conus (Strategoconus) da Motta, 1991 represented as Conus Linnaeus, 1758 Ximeniconus Emerson & Old, 1962: synonym of Conasprella (Ximeniconus) Emerson & Old, 1962 represented as Conasprella Thiele, 1929 Yeddoconus Tucker & Tenorio, 2009: synonym of Conasprella (Endemoconus) Iredale, 1931 represented as Conasprella Thiele, 1929
While it was decorated for valor in the conflict, it also triggered the only episode of open rebellion on the Italian front, in June 1917. The cause was the order to return to the trenches despite the fact that the soldiers had just been sent to the rear to rest. Many soldiers from the 142nd Regiment revolted against the officers, killing three of them along with four carabinieri. After quelling the rebellion with the help of cavalry, mobile artillery and carabinieri, the General Staff decided to punish the Brigade, as a warning against other uprisings: 28 soldiers were shot, while the survivors were sent back to the front under armed escort. The Duke investigated the causes of the rebellion while serving on the Karst Plateau. He blamed the unequal treatment versus other brigades, which enjoyed easier rest shifts. The report of General Tettoni, commander of VII Army Corps, instead blamed it on socialist propaganda and newspaper reports of the Czar's defeat in Russia. The mostly peasant soldiers had been promised an allocation of land derived from large estates after the war. The lack of political will in the implementation of this promise, together with nationalistic tensions due to the Fiume and Dalmatian question, generated a climate of resentment and social unrest, which turned into strikes, anti-government demonstrations and occupations of uncultivated land by the peasants, who organized in leagues or federations of different political colorings.
== Real-life analogues == The phase transitions without any thermal effect and into the state of lower entropy described in the book are purely fictional and impossible according to current theories of physics. In the assumption that the phase transition was described inaccurately and has thermal effects (which were not described within the novel), it would have happened without any outside intervention. The initial seed being nucleated spontaneously was due to fluctuations that are always present, the same way that the ordinary liquid-solid transitions happen. Supercooling is only possible when nucleation cannot occur, which is difficult in normal circumstances due to natural impurities in water. While multiple polymorphs of ice exist, none have the properties described in the novel, and none are stable at standard temperature and pressure. The real Ice IX has none of the properties of Vonnegut's creation, and can exist only at extremely low temperatures and high pressures. Ice VII is stable at room temperature, but only under very high pressures. The ice-nine-like phenomenon has occurred with a few other kinds of crystals, called "disappearing polymorphs". In these cases, a new variant of a crystal has been introduced into an environment, replacing many of the older form crystals with its own form. One example is the anti-AIDS medicine ritonavir, where the newer polymorph destroyed the effectiveness of the drug in solid form, requiring a change to the less efficacious liquid form.
Global Fossil Infrastructure Tracker API – the trade association of the US oil industry. (American Petroleum Institute) U.S. Energy Information Administration U.S. Department of Energy EIA – World supply and consumption Joint Organisations Data Initiative | Oil and Gas Data Transparency U.S. National Library of Medicine: Hazardous Substances Databank – Crude Oil "Petroleum" . The American Cyclopædia. 1879. "A Short History of Petroleum", Scientific American, August 10, 1878, p. 85
An ideal beam-splitter transmits and reflects 50% of the incident radiation. However, as any material has a limited range of optical transmittance, several beam-splitters may be used interchangeably to cover a wide spectral range. In a simple Michelson interferometer, one beam passes twice through the beamsplitter but the other passes through only once. To correct for this, an additional compensator plate of equal thickness is incorporated. For the mid-IR region, the beamsplitter is usually made of KBr with a germanium-based coating that makes it semi-reflective. KBr absorbs strongly at wavelengths beyond 25 μm (400 cm−1), so CsI or KRS-5 are sometimes used to extend the range to about 50 μm (200 cm−1). ZnSe is an alternative where moisture vapour can be a problem, but is limited to about 20 μm (500 cm−1). CaF2 is the usual material for the near-IR, being both harder and less sensitive to moisture than KBr, but cannot be used beyond about 8 μm (1,200 cm−1). Far-IR beamsplitters are mostly based on polymer films, and cover a limited wavelength range.
Sources: en.wikipedia.org
Americium-243, an alpha emitter, has a half-life of 7350 years, the longest of all americium isotopes. It is formed in the nuclear fuel cycle mainly by neutron capture on plutonium-242 followed by beta decay. Production increases exponentially with increasing burnup as a total of 5 neutron captures on 238U are required. If MOX-fuel is used, particularly MOX-fuel high in 241Pu and 242Pu, more americium overall and more 243Am will be produced. It decays by either emitting an alpha particle (decay energy 5.439 MeV) to become 239Np, which then quickly goes to 239Pu, or, very rarely, spontaneous fission. The fission rate is about 60% that of americium-241 or about 0.7/g/s. As for the other americium isotopes, and more generally for all alpha emitters, 243Am is carcinogenic in case of internal contamination after being inhaled or ingested. 243Am also presents a risk of external irradiation associated with the gamma ray emitted by its short-lived decay product 239Np. The external irradiation risk for the other two americium isotopes (241Am and 242mAm) is less than 10% of that for americium-243.
=== Health === Differentiating healthy versus cancerous bladder cells with metabolic footprinting. Footprinting, in combination with other techniques, for early recognition of outbreak and strain characterization. Studying aging with C. elegans exometabolomics. Extracellular metabolite analysis to evaluate pathogenic mechanism of intracellular protozoal parasite.
=== VGLUTs === Three types of vesicular glutamate transporters are known, VGLUTs 1–3 (SLC17A7, SLC17A6, and SLC17A8 respectively) and the novel glutamate/aspartate transporter sialin. These transporters pack the neurotransmitter into synaptic vesicles so that they can be released into the synapse. VGLUTs are dependent on the proton gradient that exists in the secretory system (vesicles being more acidic than the cytosol). VGLUTs have only between one hundredth and one thousandth the affinity for glutamate that EAATs have. Also unlike EAATs, they do not appear to transport aspartate.
=== The avidin-biotin system === The avidin–biotin system is a technique for studying the interaction between two biomolecules in an indirect manner, as follows: Biotin is chemically coupled to a binder molecule (e.g., a protein, DNA, hormone, etc.) without disturbing the interaction with its target molecule; avidin is then used to “sandwich” between the biotinylated binder and a reporter molecule or probe. This allows for a variety of tasks, including localization and identification of the binder or target molecule. Consequently, the avidin-biotin system can frequently replace radioactive probes. Together with Ed Bayer, Wilchek established the Avidin-biotin system as a powerful tool in biological sciences. Early in the 1970s, they exploited Avidin as a probe and developed new methods and reagents to biotinylate antibodies and other biomolecules. Today, the system is applied in research and diagnostics as well as medical devices and pharmaceuticals. Examples include western blot, ELISA, ELISPOT and pull-down assays. More recently, Wilchek participated in structural studies of the avidin–biotin complex, to characterize the unique properties of this strong interaction. The studies have culminated in the determination of the 3D structure of the avidin–biotin complex by X-ray crystallography, which aids in the design of specific artificial recognition sites.
== Biological role == Carbon dioxide is an end product of cellular respiration in organisms that obtain energy by breaking down sugars, fats and amino acids with oxygen as part of their metabolism. This includes all plants, algae and animals and aerobic fungi and bacteria. In vertebrates, the carbon dioxide travels in the blood from the body's tissues to the skin (e.g., amphibians) or the gills (e.g., fish), from where it dissolves in the water, or to the lungs from where it is exhaled. During active photosynthesis, plants can absorb more carbon dioxide from the atmosphere than they release in respiration.
Sources: en.wikipedia.org
Low temperature slows hydrolysis and oxidation, the two main routes by which the peptide backbone and side chains are modified. A lyophilised powder stored at −20 °C is more stable than one kept at room temperature, and once the material is dissolved the degradation rate rises, making refrigeration more important.
Liquid chromatography coupled to mass spectrometry is the most common approach because it combines a retention time with a mass measurement. A chromatographic peak alone cannot establish which peptide is present, so mass determination or amino acid analysis is used as an orthogonal confirmation alongside the separation.
This depends on buffer, pH, and concentration, and published stability data for this peptide are limited. In practice laboratories work through a refrigerated solution within a few weeks and discard samples that show cloudiness or visible particles. Freezing and thawing repeatedly is generally discouraged.
No. It is a synthetic analogue carrying four amino acid changes, a lactam ring and an amidated C-terminus. The natural hormone is a linear thirteen-amino-acid peptide processed from proopiomelanocortin.