Melanotan-2 (MT-2): What It Is, How It Works, and How It Differs From MT-1

Melanotan-2 (MT-2) is a lab-made version of alpha-MSH, the natural hormone that tells skin cells to make pigment. The natural hormone breaks down within minutes. MT-2 was built to last, which makes it one of the most used tools for studying the melanocortin system, the group of receptors that control pigment and several other body signals.

This guide covers what MT-2 is, why researchers use it, how it differs from Melanotan-1 (afamelanotide), and what to check before you buy it. Everything here is for research and laboratory use only.

Key Takeaways

• Melanotan-2 (MT-2) is a synthetic, ring-shaped peptide of seven amino acids, based on alpha-melanocyte-stimulating hormone (alpha-MSH). CAS 121062-08-6, molecular weight about 1024.2 g/mol, formula C50H69N15O9.
• It switches on several melanocortin receptors at once (MC1R, MC3R, MC4R and MC5R), so research models show effects beyond pigment.
• Through MC1R, it drives pigment-making cells toward eumelanin, the darker melanin that protects better against sunlight.
• Melanotan-1 (afamelanotide) acts mainly on MC1R and became an approved medicine for a rare light-sensitivity disease. MT-2 acts more broadly and has stayed a research compound.
• Quality verification matters: look for third-party HPLC testing, a batch-specific COA, and purity above 99 percent.
• Researchers in 150+ countries order from Lyze Labs, with 10,000+ orders shipped. Shipping is free and tracked, and every kit is ten vials from one batch.

What Melanotan-2 Is and How It Works

Melanotan-2 was first made at the University of Arizona as a long-lasting version of alpha-MSH (Hadley, 2006). Its sequence is Ac-Nle-c[Asp-His-D-Phe-Arg-Trp-Lys]-NH2. Three changes make it useful in the lab: one amino acid swapped for norleucine, one swapped for its mirror-image form (D-phenylalanine), and a chemical bridge that closes the chain into a ring. Together they make MT-2 far harder for enzymes to break down than natural alpha-MSH.

MT-2 copies alpha-MSH and binds the melanocortin receptors. Papers call it a non-selective agonist: it switches on MC1R, MC3R, MC4R and MC5R instead of just one. MC1R sits on melanocytes, the cells that make pigment. When MT-2 binds it, the signal inside the cell drives melanogenesis, the making of melanin.

That broad reach is why researchers like MT-2 as a probe. It is also why research models show changes beyond pigment, in hormone, appetite and energy signals.

Why Researchers Are Interested in MT-2

The main draw is pigment. Through MC1R, MT-2 raises the making of eumelanin, the brown-black pigment that protects better against sunlight than the lighter, red-yellow pheomelanin. That makes it a standard tool for studying how the melanocortin system controls pigment, including in models with MC1R gene variants that lean toward pheomelanin.

The other receptors open more questions. MT-2 switches on MC4R in the hypothalamus, a key receptor in hunger and fullness. In a classic study, MT-2 (as MTII) cut food intake in mice through this pathway (Fan, 1997), and it has been a reference compound in appetite and energy research since. PT-141 (bremelanotide), a close relative made from MT-2, is studied for the same family of receptors; see the PT-141 guide.

Reviews in dermatology make the same point: melanotropic peptides are valuable research tools, and unlicensed use outside the lab carries real risks (Langan, 2010). MT-2 is a well-studied research tool, not an approved medicine, which is why it stays in controlled lab work. For skin research beyond pigment, see the GHK-Cu copper peptide research guide.

How MT-2 Compares to Melanotan-1 (Afamelanotide)

The most common comparison is MT-2 against Melanotan-1, also called afamelanotide. The key difference is how many receptors each one hits. Melanotan-1 acts mainly on MC1R and went through full clinical development for erythropoietic protoporphyria (EPP), a rare disease where sunlight causes severe pain. It is now approved for EPP as an implant under the name Scenesse (Wensink, 2021). Melanotan-2 hits several receptors and has stayed a research compound.

In short, labs use MT-2 to test several melanocortin receptors at once, and MT-1 when the question is only about MC1R and pigment. They do different jobs. Both are available as kits: MT-2 and Melanotan 1.

What to Look For in MT-2 Quality

For a research peptide, the supplier's lab data matters more than its marketing. Three documents separate reliable material from doubtful stock.

First, a batch-specific Certificate of Analysis (COA). The COA should tie directly to the lot you receive, not a generic sample. Second, third-party HPLC (high-performance liquid chromatography) data confirming purity, ideally above 99 percent, since contaminants and truncated sequences confound melanogenesis readouts. Third, mass spectrometry confirmation that the measured molecular weight matches the expected approximately 1024.2 g/mol for the acetate salt form. Lyze Labs publishes batch COAs and HPLC results so researchers can verify identity and purity before designing experiments.

If you are new to reading these documents, our guide to verifying research peptide purity and COA data walks through each panel line by line. It also pays to know the warning signs of an unreliable vendor, which we cover in research peptide scam red flags. Skipping verification is the single most common reason melanocortin experiments fail to replicate.

Reconstitution and Storage Notes for Research Use

MT-2 arrives as a freeze-dried (lyophilized) powder, the stable form for shipping and long-term storage. In the lab, the powder is mixed with bacteriostatic or sterile water before use. The strength depends on the vial size and how much water the lab adds, so it is worked out for each study, never assumed.

Storage is simple but strict. Freeze-dried MT-2 kept cold and away from light stays stable. Once mixed, keep the solution in the fridge at 2 to 8°C and use it within about two to four weeks. Avoid freezing and thawing it again and again, which breaks peptide chains. Write the mixing date on each vial so results can be repeated. For the full method, see how to reconstitute research peptides and the peptide storage and stability guide.

Sourcing Melanotan-2 Globally

Lyze Labs supplies pharmaceutical-grade Melanotan-2 (MT-2) acetate with third-party HPLC testing, per-batch COAs, and purity above 99 percent. Each kit is ten vials from one batch, so the first vial of a study matches the last.

Add the kit to your cart and place your order. A person confirms it, sends payment options and answers questions, day or night. You can pay by Visa, Mastercard, Amex, PayPal, Apple Pay, Google Pay, bank transfer, local wallets and bank apps in your region, or crypto (USDT, USDC, BTC). Shipping is free and tracked to 150+ countries, most orders arrive in 7 to 14 days, and delivery is guaranteed.

Frequently Asked Questions

What is Melanotan-2 used for in research?

In the lab, Melanotan-2 is used to switch on several melanocortin receptors at once, to study how pigment is made, how the receptors work, and hormone and appetite signals. Because it activates MC1R, MC3R, MC4R and MC5R, one stable compound can probe several pathways. It is for research use only.

How is Melanotan-2 different from Melanotan-1?

Melanotan-2 switches on several melanocortin receptors, while Melanotan-1 (afamelanotide) acts mainly on MC1R. Melanotan-1 went through clinical trials and is approved as Scenesse for erythropoietic protoporphyria. In research models MT-2 gives broader effects, and MT-1 stays focused on MC1R and pigment.

What is the molecular weight and CAS number of MT-2?

Melanotan-2 has a molecular weight of approximately 1024.2 g/mol and the chemical formula C50H69N15O9, with CAS number 121062-08-6. Its peptide sequence is Ac-Nle-c[Asp-His-D-Phe-Arg-Trp-Lys]-NH2. Mass spectrometry on a quality COA should confirm this molecular weight for the acetate salt.

How should research-grade Melanotan-2 be stored?

Keep the freeze-dried powder cold and away from light. Once mixed with bacteriostatic or sterile water, keep it in the fridge at 2 to 8°C, use it within about two to four weeks, and avoid repeated freezing and thawing.

How can I verify the purity of Melanotan-2 before buying?

Request a batch-specific Certificate of Analysis backed by third-party HPLC data showing purity above 99 percent, plus mass spectrometry confirming the expected molecular weight. Lyze Labs provides per-batch COAs and HPLC results so identity and purity can be checked before any experiment. Our COA verification guide explains how to read each panel.

How do I order Melanotan-2 from Lyze Labs?

Add the MT-2 kit to your cart and place your order. A person confirms it and sends payment options; you can pay by card, PayPal, Apple Pay, Google Pay, bank transfer, local wallets or crypto. Orders paid before the daily batch closes are processed that day, ship free and tracked, and usually arrive in 7 to 14 days.

Studies Cited

• Hadley ME, Dorr RT (2006). Melanocortin peptide therapeutics: historical milestones, clinical studies and commercialization. Peptides.
• Fan W, et al. (1997). Role of melanocortinergic neurons in feeding and the agouti obesity syndrome. Nature.
• Langan EA, et al. (2010). Melanotropic peptides: more than just 'Barbie drugs' and 'sun-tan jabs'? British Journal of Dermatology.
• Wensink D, et al. (2021). Afamelanotide for prevention of phototoxicity in erythropoietic protoporphyria. Expert Review of Clinical Pharmacology.