This is a working overview of mass spectrometry, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-01-01 and is reviewed periodically as new material appears.
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.
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.
Melanotan II is a synthetic peptide analog modeled on alpha-melanocyte-stimulating hormone, a naturally occurring signaling peptide involved in pigmentation. Its structure is a cyclic heptapeptide containing two non-natural substitutions, norleucine at position four and D-phenylalanine at position seven. These modifications resist enzymatic breakdown and extend the molecule's activity relative to the native hormone. The compound binds melanocortin receptors and is studied mainly as a pharmacological tool rather than a therapeutic product. It has never received approval as a medicine in any major jurisdiction.
| Property | Value | Notes |
|---|---|---|
| Appearance | White to off-white powder | Lyophilised material may be hygroscopic |
| Solubility class | Soluble in water, DMSO and DMF | Dilution into aqueous buffer can cause precipitation |
| Storage of solid | Minus 20 degrees C, desiccated, dark | Aliquot to limit repeated opening of the vial |
| Storage of solution | Minus 20 to minus 80 degrees C, aliquoted | Avoid repeated freeze-thaw cycles |
| Identity method | Reversed-phase HPLC with mass spectrometry | Retention time and mass are checked together |
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-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.
The peptide acts as a non-selective agonist at melanocortin receptors, showing affinity for MC1R, MC3R, MC4R and MC5R. Activation of MC1R on melanocytes drives the conversion of tyrosine into melanin and shifts production toward the darker eumelanin form. MC4R signalling in the central nervous system is linked to appetite and energy balance, which helps explain why reduced food intake appeared in early human studies. Effects on MC4R and on vascular tone also account for the erectile responses recorded as unexpected findings in those same trials.
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 II holds no marketing authorisation from the Food and Drug Administration, the European Medicines Agency, the UK Medicines and Healthcare products Regulatory Agency or Australia's Therapeutic Goods Administration. Products sold under that name are treated as unapproved new drugs, and their sale or import is prohibited in several jurisdictions. Other countries classify the peptide as a prescription-only medicine or place it among controlled substances, so the legal position changes with the destination market. No pharmacopoeial monograph supplies an official specification, because the material is not a licensed pharmaceutical. Consequently, products offered online are not manufactured to a shared public standard.
The peer-reviewed record is dominated by small early-phase studies, case reports and pharmacovigilance summaries rather than large randomised trials. Papers typically examine tanning response, receptor selectivity or patterns of reported adverse events. Many note that participants obtained the peptide outside a clinical setting, which limits verification of composition and administered amount. Reported events vary widely, and causality is frequently unclear because the identity and purity of self-sourced material are unknown. Open questions include whether repeated melanocortin receptor stimulation produces cumulative effects, and how often label claims match actual content.
==== Economic gains ==== In 2014, the aquaculture produced fish overtook wild caught fish, in supply for human food. This means there is a huge demand for vaccines, in prevention of diseases. The reported annual loss fish, calculates to >10 billion USD. This is from approximately 10% of all fishes dying from infectious diseases. The high annual losses increases the demand for vaccines. Even though there are about 24 traditionally used vaccines, there is still demand for more vaccines. The breakthrough of DNA-vaccines has sunk the cost of vaccines. The alternative to vaccines would be antibiotics and chemotherapy, which are more expensive and with bigger drawbacks. DNA-vaccines have become the most cost-efficient method of preventing infectious diseases. This bodes well for DNA-vaccines becoming the new standard both in fish vaccines, and in general vaccines.
Unlike classes I and II, Class III molecules have physiological roles and are encoded between classes I and II on the short arm of human chromosome 6. Class III molecules include several secreted proteins with immune functions: components of the complement system (such as C2, C4, and B factor), cytokines (such as TNF-α, LTA, and LTB), and heat shock proteins.
=== Morphology === The morphologic variations in the size, shape, volume, tissue density, pectoral locale, and spacing of the breasts determine their natural shape, appearance, and position on a woman's chest. Breast size and other characteristics do not predict the fat-to-milk-gland ratio or the potential for the woman to nurse an infant. The size and the shape of the breasts are influenced by normal-life hormonal changes (thelarche, menstruation, pregnancy, menopause) and medical conditions (e.g. breast hypertrophy). The shape of the breasts is naturally determined by the support of the suspensory Cooper's ligaments, the underlying muscle and bone structures of the chest, and by the skin envelope. The suspensory ligaments sustain the breast from the clavicle (collarbone) and the clavico-pectoral fascia (collarbone and chest) by traversing and encompassing the fat and milk-gland tissues. The breast is positioned, affixed to, and supported upon the chest wall, while its shape is established and maintained by the skin envelope. In most women, one breast is slightly larger than the other. More obvious and persistent asymmetry in breast size occurs in up to 25% of women. The base of each breast is attached to the chest by the deep fascia over the pectoralis major muscles. The base of the breast is semi-circular, however the shape and position of the breast above the surface is variable. The space between the breast and the pectoralis major muscle, called retromammary space, gives mobility to the breast.
In 1927, Max Oberlin studied the pharmacology of MDMA while searching for substances with effects similar to adrenaline or ephedrine, the latter being structurally similar to MDMA. Compared to ephedrine, Oberlin observed that it had similar effects on vascular smooth muscle tissue, stronger effects at the uterus, and no "local effect at the eye". MDMA was also found to have effects on blood sugar levels comparable to high doses of ephedrine. Oberlin concluded that the effects of MDMA were not limited to the sympathetic nervous system. Research was stopped "particularly due to a strong price increase of safrylmethylamine", which was still used as an intermediate in methylhydrastinine synthesis. Albert van Schoor performed simple toxicological tests with the drug in 1952, most likely while researching new stimulants or circulatory medications. After pharmacological studies, research on MDMA was not continued. In 1959, Wolfgang Fruhstorfer synthesized MDMA for pharmacological testing while researching stimulants. It is unclear if Fruhstorfer investigated the effects of MDMA in humans. Outside of Merck, other researchers began to investigate MDMA. In 1953 and 1954, the United States Army commissioned a study of toxicity and behavioral effects in animals injected with mescaline and several analogues, including MDMA. Conducted at the University of Michigan in Ann Arbor, these investigations were declassified in October 1969 and published in 1973.
Sources: en.wikipedia.org
=== VUV spectral identification === Gas phase species absorb and display unique spectra between 120 and 240 nm where high energy σ→σ*, n→σ*, π→π*, n → π* electronic transitions can be excited and probed. VUV spectra reflect the absorbance cross section of compounds and are specific to their electronic structure and functional group arrangement. The ability of VUV detectors to produce spectra for most compounds results in universal and highly selective compound identification. VUV spectroscopy data is highly characteristic while also providing quantitative information. Many commonly used GC detectors such as the electron capture detector (ECD), flame ionization detector (FID), and thermal conductivity detector (TCD) produce quantitative but not qualitative detail. Gas chromatography–mass spectrometry (GC-MS) generates qualitative and quantitative data but has difficulty characterizing labile and low mass compounds, as well as differentiating between isomers. GC-VUV complements MS by overcoming its limitations and providing a secondary method of confirmation. It also offers a single-instrument alternative to the use of multiple detectors for qualitative and quantitative analysis.
==== Spiritual counseling ==== Spiritual counsellors meet with people in need to offer comfort and support and to help them gain a better understanding of their issues and develop a problem-solving relation with spirituality. These types of counselors deliver care based on spiritual, psychological and theological principles.
== Music and lyrics == Guitarist-vocalist Bill Steer retrospectively said that "The first album wasn’t very focused, it was just about being fast and heavy..." He went on to say that the band did not intend the muddy sound present throughout the album: "The first one obviously is a crazy accident. It’s got a small following but we did not intend to make that record the thing that people hear now. We had different ideas and we just couldn’t execute them. We were too young, too naïve, and inexperienced. From 'Symphonies' onwards, we got better at achieving the things we wanted to achieve in the studio." Revolver said that the album's music was "hectic, brutal and sounds like it was recorded beneath a stack of wet mattresses." Invisible Oranges wrote: "Carcass’ 1988 [debut] set new standards for auditory dismemberment, channeling the sound of Napalm Death through a vomited, gore-encrusted wormhole backwards. This is the aural nightmare of the dissecting table pushed beyond the extremes previously explored by the tinny sounds of blackthrash with bowl-rupturing, gurgling low end. Ken Owen flails about so nightmarishly you can’t even really distinguish if he’s even playing drums or has merely taken the contents of mortician’s tools of the trade and thrown them out of the window of morgue into the biohazard-labeled dumpster." Lyrical themes explored on the album include vomitting, feces, wound healing, and foeticide. According to Revolver, the track "Foeticide" is a "horrific description of abortion by electrocution [...] a mad scientist frying human babies in their wombs."
Sources: en.wikipedia.org
=== Clinical and clinicopathologic research and scholarship === Jennette and his associates have performed and published clinical and clinicopathologic studies, and recommendations for the management, diagnosis, and classification of kidney diseases. He was a member of consensus groups that published recommendations for pathologic diagnosis of kidney transplant rejection, focal segmental glomerulosclerosis, IgA nephropathy, membranoproliferative glomerulonephritis, C1q nephropathy, membranous nephropathy, lupus nephritis, and ANCA glomerulonephritis. In 1994 and 2012, Jennette and his associate Falk led two international consensus conferences that standardized the names and pathologic features of different forms of vascular inflammation (vasculitis). Jennette and Falk established the Glomerular Disease Collaborative Network (GDCN) in 1985 to promote collaborative research on glomerular disease among UNC faculty in nephrology and nephropathology, along with community practice nephrologists who refer kidney biopsies to UNC for diagnosis. Clinical and clinicopathologic research projects have utilized GDCN resources, including the article published by Jennette and Falk in The New England Journal of Medicine in 1988, which reported the discovery that one major antigen target of ANCA is myeloperoxidase (MPO-ANCA) and clarified the diverse clinical and pathologic spectrum of ANCA disease, using data and samples obtained through the GDCN. In 1990, they documented that the other major antigen specificity of ANCA is proteinase 3 (PR3-ANCA).
== Preparation == Phthalimide can be prepared by heating phthalic anhydride with alcoholic ammonia giving 95–97% yield. Alternatively, it may be prepared by treating the anhydride with ammonium carbonate or urea. It can also be produced by ammoxidation of o-xylene.
In 2019, the European Medicines Agency's Pharmacovigilance Risk Assessment Committee (PRAC) recommended that product labels for all SSRIs and SNRIs, including sertraline, be updated to state that sexual dysfunction may be long-lasting even after treatment is stopped. Health Canada followed with similar label updates in 2021. In 2024, Australia's Therapeutic Goods Administration aligned all SSRI and SNRI product information to reflect this risk, noting that sertraline already carried a warning about persistent sexual dysfunction.
Sources: en.wikipedia.org
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.
Peptides are commonly isolated as acetate or trifluoroacetate salts, and the counterion contributes to total mass. Two vials with identical peptide content can therefore differ in weight and in measured response. Residual trifluoroacetate is also relevant in cell-based work because it can influence membrane behaviour.
Degradation products are often closely related to the parent molecule, making them hard to resolve with a single method. Counterion variability adds a further source of scatter between laboratories. Because no pharmacopoeial monograph exists for melanotan-2, groups rely on method-specific validation rather than a shared reference standard.
It is a synthetic cyclic peptide designed as an analog of alpha-melanocyte-stimulating hormone. It acts on melanocortin receptors and is best known from research into pigmentation. It is not an approved pharmaceutical product.