Buy Melanotan II Research Peptide

Melanotan II (CAS 121062-08-6), also known as MT-2 or MT-II, is a synthetic cyclic heptapeptide and non-selective melanocortin receptor agonist with the molecular formula C₅₀H₆₉N₁₅O₉ and a molecular weight of 1024.18 g/mol. Its structure, Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH2, is a truncated analogue built on the conserved message sequence of the endogenous linear tridecapeptide alpha-MSH, with three key modifications: a norleucine substitution that confers resistance to oxidative degradation, a D-phenylalanine residue that provides proteolytic stability, and an Asp-Lys lactam bridge (positions 2-7) that constrains the peptide into a cyclic conformation. Originally developed by Hruby and colleagues in the 1980s as part of systematic alpha-MSH analogue research, Melanotan II was produced via solid-phase peptide synthesis and activates MC1R, MC3R, MC4R, and MC5R with no significant activity at MC2R, giving it an agonist profile across the melanocortin receptor family.

Melanotan II helped establish the synthetic cyclic melanocortin agonist series. Its non-selective profile, with binding affinities and functional potencies in the low nanomolar range across MC1R, MC3R, MC4R, and MC5R and no activity at MC2R, has made it an indispensable reference agonist for characterising the contributions of receptor subtypes to central and peripheral signalling. In vitro studies have evaluated Melanotan II at cloned human melanocortin receptors, measuring radioligand binding affinity and Gs-coupled cAMP accumulation, and established it as a potent, non-selective full agonist [1][2]. The compound also served as the parent structure for more subtype-selective analogues. Structure-activity studies comparing Melanotan II with its linear alpha-MSH precursor and position-modified cyclic analogues helped define the pharmacophore requirements for receptor activation and subtype selectivity: the conserved His-Phe-Arg-Trp message sequence, Nle and D-Phe substitutions, and Asp-Lys lactam constraint [2][3].

Melanotan II is manufactured in a cGMP compliant, ISO9001 certified laboratory to a guaranteed purity of 98% or above. Every batch is independently tested using HPLC and MS-UPLC analysis before dispatch. Vials are vacuum sealed and stored in a temperature controlled, monitored cold storage system to preserve compound integrity throughout the supply chain. Certificates of Analysis are available on request.

Sold strictly for in vitro research purposes only. Not for human consumption. Intended for use by qualified researchers in laboratory settings only.

Scientific Review

Dr. Martina Rossi, PhD

Scientific Contributor and Reviewer

Reviewed for scientific accuracy, 14 June 2026

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