Melanotan II (MT‐2) Research Peptide Overview

Melanotan II is a high-purity, research-grade cyclic peptide analogue of alpha‐melanocyte‐stimulating hormone (α‐MSH), developed to probe melanocortin receptor biology in controlled experimental systems. This compound enables detailed investigation of melanogenesis, neuroendocrine signaling, appetite regulation, and metabolic pathways within a single, structurally defined framework.

Molecular Composition and Mechanistic Profile

• Melanotan II (MT‐2): A synthetic cyclic heptapeptide derived from the α‐MSH sequence and optimized for enhanced receptor affinity and in vivo stability.

• Peptide sequence: Nle‐Asp‐His‐D‐Phe‐Arg‐Trp‐Lys‐NH2 (often written as Nle‐Asp(1)‐His‐D‐Phe‐Arg‐Trp‐Lys(1)), incorporating non‐natural residues and a cyclic backbone to resist enzymatic degradation and prolong biological activity in preclinical models.

• Receptor profile: MT‐2 acts as a potent agonist at multiple melanocortin receptors, with primary activity at MC1R and MC4R and additional, weaker engagement of MC3R and MC5R, enabling simultaneous study of peripheral pigmentation and central neuroendocrine effects.

  Through this multimodal receptor engagement, Melanotan II supports research into melanogenesis, sexual function, feeding behavior, addiction circuitry, and inflammatory and immune modulation.

Integrated Research Applications

• Melanotan II is widely used to model how targeted melanocortin activation influences diverse physiological systems in vitro and in vivo. Representative experimental domains include:

• Melanogenesis and photoprotection models assessing pigment production, UV‐induced damage, and melanin distribution in melanocyte and skin constructs.

• Neuroendocrine and sexual function studies examining MC4R‐linked pathways, arousal circuits, and hypothalamic signaling in preclinical models.

• Metabolic and appetite regulation experiments evaluating food intake, energy expenditure, glucagon dynamics, and leptin–melanocortin cross‐talk.

• Neuroprotection and behavior research exploring compulsive behavior, addiction, sleep–wake regulation, and neuroinflammation via central melanocortin pathways.

By using a single, well-characterized agonist, investigators can track both skin‐focused and central nervous system responses to melanocortin receptor stimulation under standardized dosing conditions.

Analytical Validation and Quality Assurance

Commercial MT‐2 preparations are supplied as lyophilized powder (e.g., 10 mg per vial) at high purity (typically ≥98–99%), with quality confirmed by high‐performance liquid chromatography (HPLC) and mass spectrometry (MS). Product documentation generally includes peptide content, CAS number, molecular formula, molecular weight, and confirmation of analytical testing, supporting batch‐to‐batch reproducibility for laboratory protocols.

These features make Melanotan II suitable for assays requiring precise quantitation, consistent reconstitution, and stable performance across repeated experimental cycles.

Storage and Stability Guidelines

Proper handling of Melanotan II is essential to maintain peptide integrity and experimental reliability. Typical guidance from suppliers includes:

• Lyophilized (unopened): Store in a cool, dry environment away from light; refrigeration is recommended for extended shelf life.

• Reconstituted solutions: Keep refrigerated, protected from light, and use within a defined time window according to institutional laboratory practices and sterility controls.
  
  This research peptide is not suitable or permitted for use as a tanning agent, weight-loss aid, or any other human-directed purpose, and it must be handled as a research-only material under institutional guidelines.​