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Melanocortin receptor agonist · regulated research peptide
Supply and ordering
Ask sales about Melanotan II availability, order quantities, packaging, and batch documentation. Include other catalog items in the same inquiry if you are planning a combined or recurring order.
Overview
Melanotan II (MT-II) is a synthetic cyclic heptapeptide analog of α-MSH developed at the University of Arizona in the 1980s. The molecule is a non-selective agonist at multiple melanocortin receptors (MC1R, MC3R, MC4R, MC5R), and the broad receptor profile is what produces both the studied pigmentation effects (via MC1R on melanocytes) and the studied sexual-function effects (via MC4R in CNS). The cyclic structure, a lactam bridge between Lys10 and Asp5 of the parent α-MSH sequence, provides both protease resistance and a constrained active conformation that increases receptor binding affinity relative to the linear parent peptide. PeptideXpo supplies Melanotan II as a lyophilized powder to a ≥99.0% HPLC purity specification. The cyclized structure requires careful synthesis and the analytical packet includes mass spec confirming the cyclic mass (1024.18 Da theoretical, -18 Da relative to the linear precursor due to the lactam-forming dehydration). MT-II is heavily regulated in major jurisdictions including the UK, Australia, EU markets, and Canada, and banned for direct human consumption in many; the product is supplied as a research material only and is not intended or sold for any use that would constitute human administration in jurisdictions where it is prohibited.
Who buys this, and why
Cosmetic-peptide buyers fall into two groups: established beauty / med-aesthetic brands extending an existing line, and OEM clients building a private-label catalog from scratch. The first group usually wants bulk active plus stability data in their existing carrier matrix; the second usually wants a finished formulation under their label. Both need INCI naming verified, regulator-specific safety files (CPNP for EU, FDA OTC monograph for US where relevant), and packaging-compatibility data.
Primary buyer fit: academic and contract research laboratories.
Specifications
Also available as a nasal spray (US stock)
Besides lyophilized vials, Melanotan II is stocked in the US as a ready-to-use nasal spray.
Documentation available on request
Each picture is a low-resolution preview of a report's first page, with batch and report numbers covered. For the full, clear report, ask our sales team, naming the product and strength.
Batch COAMelanotan II 10 mg
HPLC purity · MS identity
Batch COA
Full, clear copy from sales
Independent test fails? Full refund. How it works
Regulatory note
Heavily regulated; banned for human use in multiple jurisdictions including UK, Australia, and several EU markets. Sold only to qualified buyers with appropriate licensing in their jurisdiction for legitimate research use. Order requires compliance review.
Selected literature
Frequently asked questions
Both are α-MSH analogs designed to drive melanocortin-receptor signaling, but they differ structurally and pharmacologically. Melanotan I (Afamelanotide) is a linear 13-amino-acid α-MSH analog with [Nle4, D-Phe7] substitutions that provide protease resistance, it is selective for MC1R (the pigmentation receptor) over the other melanocortin receptors, which is why it became approvable as a prescription drug for erythropoietic protoporphyria. Melanotan II is a cyclic 7-residue analog with broader (non-selective) activity across MC1R, MC3R, MC4R, and MC5R, the broader receptor profile drives both pigmentation effects and the off-target effects (CNS, cardiovascular, sexual-function) that make MT-II more heavily regulated than MT-I in most jurisdictions.
Melanotan II's biological activity depends on the cyclic conformation produced by a lactam bridge between Lys10 and Asp5 of the parent α-MSH sequence. The cyclic and linear (uncyclized) forms differ by 18 Da in mass (the water lost during lactam formation) and elute at substantially different RP-HPLC retention times. The linear precursor has dramatically reduced receptor-binding affinity compared with the cyclic form, so analytical confirmation that the released-batch material is the cyclized form is essential. The COA should explicitly report mass spec confirming the cyclized mass (≈1024 Da theoretical), if the dominant species elutes at the linear-precursor mass, the cyclization step did not complete and the material lacks the defining MT-II pharmacology.
Yes. Melanotan II is also stocked as a ready-to-use nasal spray (10 mg, 20 mg) in 10 mL or 20 mL bottles, from 10 bottles of each. These orders ship from our US stock; ask our sales team for details and a quote.
Send any vial from your order to an independent laboratory of your choice. If the report shows the product does not meet the specification on its COA — purity below the stated minimum, or an identity that does not match — share the report with our sales team and we refund that product in full.
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