Melanotan-II 10mg — 45 Sprays

Scientific identity

Melanotan-II (CAS 121062-08-6) is a synthetic cyclic melanocortin research compound. Its molecular formula is C₅₀H₆₉N₁₅O₉ and molecular weight is 1,024.20 g/mol. The sequence is Ac-Nle-c[Asp-His-D-Phe-Arg-Trp-Lys]-NH₂ — a 7-residue seven-residue compound with an N-terminal acetyl group, C-terminal primary amide, and a covalent lactam bridge between the Asp and Lys side chains constraining the molecule into a cyclic conformation.

Compound class

Synthetic cyclic melanocortin research compound; synthetic α-MSH analogue; broad-spectrum melanocortin receptor research agonist. Classified as a Research Use Only material and is not a drug, dietary supplement, food, or cosmetic.

Structural architecture

The defining structural feature of Melanotan-II is its cyclic lactam bridge — a covalent bond between the β-carboxyl side chain of Asp and the ε-amino side chain of Lys — constraining the pharmacophoric His-D-Phe-Arg-Trp core into a defined cyclic conformation. This cyclization was studied to characterize conformational requirements for melanocortin receptor binding and to investigate whether structural constraint alters receptor selectivity relative to linear α-MSH analogues.

Distinction from Melanotan-I and afamelanotide

Melanotan-I is a linear 13-amino-acid α-MSH analogue (C₇₈H₁₁₁N₂₁O₁₉, MW ~1,646.87 g/mol) — a fundamentally different molecular scaffold from the cyclic seven-residue compound Melanotan-II. Afamelanotide shares Melanotan-I's sequence and holds EMA and FDA approval as Scenesse for EPP; this regulatory status applies to the pharmaceutical product specifically and does not extend to Melanotan-II or to any Longevia Research spray. The three compounds engage the melanocortin receptor family through overlapping but distinct pharmacological profiles and are not interchangeable research tools.

Receptor profile

MC1R (melanocytes; pigmentation biology), MC3R (hypothalamus; neuroendocrine and energy-balance research), MC4R (hypothalamus; appetite regulation and energy homeostasis research), and MC5R (exocrine glands; secretory function research). Receptor-binding data represents pharmacological characterization in defined assay systems, not established clinical outcomes.

Product content: 10mg per bottle; 45 sprays per bottle.

Physical form: Liquid research spray.

Purity: Research-grade.

Analytical documentation: A batch-specific Certificate of Analysis is available on the Longevia Research website, covering compound identity, purity, and lot traceability.

Research-use classification: Research Use Only. Not approved for human or veterinary use. Not intended for administration to humans or animals.

Structural design and receptor pharmacology. Melanotan-II emerged from systematic structure-activity relationship (SAR) research — conducted primarily at the University of Arizona in the laboratory of Victor Hruby and colleagues — aimed at creating conformationally constrained α-MSH analogues to probe pharmacophore requirements for melanocortin receptor binding. The cyclic lactam bridge constrains the His-D-Phe-Arg-Trp pharmacophoric core into a defined spatial arrangement, altering the presentation of key binding residues relative to linear α-MSH analogues. Receptor pharmacology studies using competitive binding assays at cloned human melanocortin receptors have characterized Melanotan-II's binding affinity and selectivity profile across MC1R, MC3R, MC4R, and MC5R — a broader receptor activity profile than Melanotan-I, which has been studied primarily at MC1R. These data represent quantitative pharmacological characterization in defined in vitro assay systems and should not be interpreted as established physiological outcomes.

MC1R and melanogenesis research. In cell-based research, MC1R activation by α-MSH analogues including Melanotan-II has been examined in relation to a signaling cascade involving adenylate cyclase stimulation, intracellular cAMP accumulation, PKA activation, and downstream induction of MITF — a transcriptional regulator driving expression of melanogenic enzyme genes including tyrosinase, TYRP1, and DCT in melanocyte cell culture systems. Studies using primary human melanocytes, murine B16 melanoma cells, and Melan-A cell lines have examined cAMP production, tyrosinase activity, and melanin content as experimental endpoints. Animal studies using pigmented murine models with functional MC1R have investigated coat color responses to melanocortin agonist administration in vivo. These are pharmacological observations in defined experimental systems; species differences in skin architecture and melanocyte biology limit direct translation to human pigmentation physiology, and these findings should not be presented as evidence of human pigmentation outcomes from this product.

MC3R and MC4R neuroendocrine research. MC3R and MC4R are expressed in hypothalamic nuclei with established roles in energy homeostasis and neuroendocrine regulation in experimental animal models. Research using genetically modified animal models — including MC4R knockout mice, which display obesity and hyperphagia — has characterized central melanocortin signaling in energy balance at the level of animal physiology. Melanotan-II has been used as a pharmacological probe in preclinical research examining central melanocortin receptor activation, with endpoints including food intake, energy expenditure, and behavioral responses in rodents under controlled laboratory conditions. These experimental findings are specific to the animal model, administration conditions, and endpoints studied. They do not constitute clinical evidence for human physiological effects and must not be converted into consumer claims about appetite, weight, metabolism, or body composition. Selected human research has also examined aspects of central melanocortin pharmacology using Melanotan-II in defined clinical research contexts using subcutaneous injection formulations — findings from these studies are specific to the compound, formulation, population, and measured outcome and cannot be transferred to the Longevia Research spray, for which no pharmacokinetic or bioavailability data are stated.

Regulatory status. Melanotan-II does not carry regulatory approval as a pharmaceutical product in any jurisdiction. Its clinical status as a research tool is distinct from approved melanocortin therapeutics including afamelanotide/Scenesse (approved for EPP) and bremelanotide/Vyleesi, each of which underwent formal pharmaceutical development under defined regulatory pathways. The Longevia Research Melanotan-II spray has not been submitted for or received regulatory approval from any agency and is supplied strictly as a Research Use Only material for qualified laboratory investigation.

For a synthetic cyclic research peptide such as Melanotan-II, research-grade quality requires not only confirmation of amino acid composition and sequence but also verification of the cyclic architecture — specifically the lactam bridge between Asp and Lys side chains — which is an intrinsic structural feature rather than a secondary modification. A preparation that lacks the cyclization, or contains the linear precursor, would be a chemically and pharmacologically different compound. Distinguishing Melanotan-II from structurally related melanocortin analogues — including Melanotan-I, α-MSH, and other cyclic melanocortin peptides — requires analytical methods capable of resolving these differences at the molecular level.

Research-grade quality assessment for Melanotan-II appropriately involves:

Peptide identity and sequence verification: Confirmation of the correct heptapeptide sequence (Ac-Nle-c[Asp-His-D-Phe-Arg-Trp-Lys]-NH₂) using LC-MS/MS tandem mass spectrometry or equivalent analytical methods capable of resolving individual residues.

Molecular mass confirmation: High-resolution mass spectrometry (HRMS) to confirm the molecular formula C₅₀H₆₉N₁₅O₉ and molecular weight of 1024.20 g/mol — analytically distinguishing Melanotan-II from Melanotan-I (MW ~1646.87 g/mol) and related melanocortin analogues.

Cyclic structure verification: Analytical confirmation that the lactam bridge is present and intact, distinguishing the cyclic form from any uncyclized linear precursor that may arise from incomplete synthesis. Mass spectrometric methods can detect the mass shift associated with lactam formation (–H₂O relative to the open-chain precursor).

Stereochemical confirmation: Verification that D-Phe at the critical pharmacophoric position is the D-stereoisomer, using chiral analytical methods or appropriate MS-based approaches.

Terminal modification verification: Confirmation of N-terminal acetylation and C-terminal amidation as structural features of the designed compound.

Purity assessment: Reversed-phase HPLC or UHPLC to assess chemical purity and quantify related substances, synthesis-related impurities, or incomplete cyclization products.

Batch documentation and traceability: Provision of batch-specific analytical records enabling traceability from synthesis through supply.

Longevia Research's quality approach is oriented toward providing researchers with well-characterized peptides supported by appropriate analytical documentation. Researchers should consult current product documentation and available certificates of analysis for batch-specific data.

No specific purity grade, third-party certification, cGMP status, or independent laboratory verification is stated for this listing. Researchers requiring documentation of specific quality parameters should contact Longevia Research directly.

FOR RESEARCH USE ONLY. NOT FOR HUMAN CONSUMPTION. NOT FOR VETERINARY USE.

Melanotan-II 10mg — 45 Sprays, as supplied by Longevia Research, is intended exclusively for qualified laboratory and scientific research conducted by trained professionals in appropriate research settings. This product is not a drug, dietary supplement, food, or cosmetic. It has not been evaluated or approved by the U.S. Food and Drug Administration, the European Medicines Agency, or any other regulatory authority for use as a therapeutic, prophylactic, or diagnostic agent in humans or animals.

This product is not intended to diagnose, treat, cure, or prevent any disease, condition, or health-related outcome.

Distinction from related compounds: Melanotan-II is chemically and pharmacologically distinct from Melanotan-I and from afamelanotide (Scenesse). Research findings concerning those compounds do not automatically establish the properties of Melanotan-II, and clinical approvals associated with afamelanotide do not extend to this research product. Evidence from any melanocortin compound study should be attributed to the specific compound and formulation studied.

Formulation distinction: Human and preclinical studies involving Melanotan-II have used injectable formulations — parenteral routes of administration with defined pharmacokinetics. Findings from those formulations and routes cannot be assumed to apply to the pharmacokinetics, bioavailability, or behavior of this spray formulation, for which no such data are stated.

Research evidence scope: Research involving Melanotan-II, Melanotan-I, α-MSH, afamelanotide, or other melanocortin receptor agonists does not establish that this specific Longevia Research spray produces equivalent biological effects in any system or population.

Pigmentation and photoprotection: Pigmentation-related research involving melanocortin receptor biology and melanogenesis does not establish that this product provides clinical UV protection, prevents UV-induced disease, or is appropriate for any cosmetic or skin-related therapeutic application. This product is not a sunscreen, photoprotective agent, or cosmetic.

Neuroendocrine and physiological research: Research involving MC3R, MC4R, and related melanocortin signaling pathways in animal models does not establish that this product affects appetite, body weight, metabolism, body composition, or any related physiological parameter in humans. Such research is experimental and model-specific.

Purchasers are solely responsible for ensuring that acquisition, possession, storage, handling, use, and disposal of this product comply with all applicable local, state, national, and international laws and regulations governing research compounds. Longevia Research makes no warranties regarding the suitability of this product for any specific research application. This product should be handled by qualified personnel following appropriate laboratory safety protocols.

By purchasing this product, the purchaser confirms that they are a qualified researcher or research professional acquiring this compound for legitimate scientific research purposes only.