# Melanotan II (MT-2)

> Cyclic α-MSH analogue acting broadly across melanocortin receptors

All products are sold strictly for laboratory research use only. Not for human or veterinary use.

- Web page: https://peptidemedixeu.com/en/products/melanotan-2/
- Brand: Peptide Medix EU
- Category: [Libido & Sexual Function](https://peptidemedixeu.com/en/collections/libido-peptides/)
- Purity: ≥99% by HPLC; lot-matched COA
- CAS number: 121062-08-6
- from €55 (EUR)

## Sizes and prices (EUR)

| Size | Price | SKU |
| --- | --- | --- |
| 10 mg | €55 | MELANOTAN-2-10-MG |
| 20 mg | €97 | MELANOTAN-2-20-MG |

_Catalog prices at build time; the web page and checkout are authoritative._

## Specifications

- **CAS number:** 121062-08-6
- **Molecular formula:** C50H69N15O9
- **Molecular weight:** 1024.18 g/mol
- **Amino acid sequence:** Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH2
- **Peptide class:** Cyclic heptapeptide; α-MSH (melanocortin) analogue
- **Form:** Lyophilized white to off-white powder, sealed glass vial
- **Purity:** ≥99% by HPLC; lot-matched COA
- **Available sizes:** 10 mg, 20 mg
- **Solubility:** Soluble in bacteriostatic or sterile water; also soluble in dilute acetic acid
- **Storage (lyophilized):** −20 °C, protected from light and moisture
- **Storage (reconstituted):** 2–8 °C, protected from light; aliquot to limit freeze–thaw
- **Receptor targets:** Non-selective agonist at MC1R, MC3R, MC4R and MC5R
- **Research areas:** Melanogenesis and pigmentation, appetite and energy balance, melanocortin receptor selectivity

## Description

Melanotan II (MT-2) is a synthetic cyclic lactam analogue of α-melanocyte-stimulating hormone that originated in university research on melanocortin structure–activity relationships. A ring formed between aspartate and lysine side chains fixes the pharmacophore in its active shape, while N-terminal acetylation, a norleucine and a D-phenylalanine slow down proteolysis. The outcome is a small heptapeptide far more stable and potent than native α-MSH.

In contrast to its metabolite PT-141, Melanotan II keeps its C-terminal amide and acts as a broad, fairly unselective agonist at MC1R, MC3R, MC4R and MC5R. That wide reach made it a staple research tool: via MC1R it links to melanogenesis and pigmentation, while via MC3R and MC4R it links to central studies of feeding, energy expenditure and arousal. Very few single compounds open up so many receptor subtypes at once.

## Frequently asked questions

### In what way do Melanotan I and II differ?

Melanotan I (afamelanotide) is a linear α-MSH analogue selective for MC1R; Melanotan II is cyclic and unselective, acting at MC1R, MC3R, MC4R and MC5R. MT-1 is chosen to study pigmentation pathways alone, MT-2 when broad melanocortin activity is what the experiment needs.

### Is a certificate of analysis available for your MT-2?

Yes. Reverse-phase HPLC (≥99% purity) and mass spectrometry (identity) characterise each lot, and the lot's certificate can be requested. The batch number on your vial matches the document, keeping results traceable.

### Which sizes are sold?

Lyophilised vials of 10 mg and 20 mg. The 10 mg vial fits short assay series or method development; with 20 mg, a longer study can run on one lot from start to finish, eliminating batch differences as a confounder.

### How do I reconstitute and store Melanotan II?

It dissolves readily in bacteriostatic or sterile water — add the solvent slowly along the glass and swirl, don't shake. Keep sealed vials at −20 °C away from light and moisture; store the solution at 2–8 °C in aliquots to avoid repeated freezing and thawing.

### What is the reason for studying it together with PT-141?

PT-141 is the free-acid metabolite of Melanotan II, lacking the C-terminal amide. Testing both reveals what that amide contributes: MT-2 retains strong MC1R activity, whereas PT-141 largely loses it — an ideal matched pair for receptor-selectivity work.

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All products offered on this website are intended solely for in-vitro laboratory research and development by qualified professionals. They are not drugs, foods, cosmetics or dietary supplements, and are not intended to diagnose, treat, cure or prevent any disease. Products must not be introduced into humans or animals in any manner. By purchasing, you confirm that you are a qualified researcher and accept full responsibility for handling and storage in accordance with applicable laws.

Peptide Medix EU · https://peptidemedixeu.com/en/products/melanotan-2/