By the Peptides Lab Ireland research team · Updated July 2026 · Research use only
Melanotan-2 (MT-2, Melanotan II) is a synthetic cyclic heptapeptide melanocortin receptor agonist studied in preclinical pigmentation, appetite and reproductive-neuroendocrinology research. This reference is for Irish research groups working with MT-2 in preclinical protocols.
What is Melanotan-2?
MT-2 is a synthetic analogue of alpha-melanocyte-stimulating hormone (α-MSH) engineered for higher potency, longer half-life and non-selective melanocortin receptor engagement. It is a cyclic heptapeptide (Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH₂) that binds MC1R, MC3R, MC4R and MC5R.
- Molecular formula: C₅₀H₆₉N₁₅O₉
- Molecular weight: ≈ 1024.2 Da
- CAS number: 121062-08-6
- Receptors: MC1R, MC3R, MC4R, MC5R
Research applications
Preclinical research literature on MT-2 covers:
- Melanocortin receptor pharmacology — non-selective MC1-5R receptor engagement studies
- Pigmentation research — MC1R-driven melanogenesis in dermal biology models
- Appetite research . MC4R-driven feeding-behaviour research
- Reproductive neuroendocrinology , MC4R central circuits
- Comparative studies vs PT-141 (bremelanotide), which has MSH activity removed
MT-2 vs MT-1 vs PT-141 , the three melanocortin research compounds
| MT-1 | MT-2 | PT-141 | |
|---|---|---|---|
| Receptor selectivity | Broad (MC1-5R) | Broad (MC1-5R) | MC4R > MC3R > MC1R |
| Pigmentation activity | Yes | Yes (high) | Reduced |
| Primary research focus | Pigmentation | Pigmentation + appetite | Reproductive/CNS |
| Structure | Linear 13aa | Cyclic heptapeptide | Cyclic heptapeptide |
Reconstitution reference typical 10 mg MT-2 vial
| Diluent | Working concentration | Volume for common research doses |
|---|---|---|
| 1.0 ml bac water | 10 mg/ml | 250 µg → 25 µl · 500 µg → 50 µl · 1 mg → 100 µl |
| 2.0 ml bac water | 5 mg/ml | 250 µg → 50 µl · 500 µg → 100 µl · 1 mg → 200 µl |
| 5.0 ml bac water | 2 mg/ml | 250 µg → 125 µl · 500 µg → 250 µl · 1 mg → 500 µl |
Full technique in our reconstitution guide. Reconstituted MT-2 is stable at 2–8 °C for approximately 3–4 weeks.
Regulatory context , with Ireland
MT-2 isn’t approved as a medicinal product in Ireland or the EU. It is supplied strictly for in-vitro laboratory research and educational use. See our HPRA regulations guide.
Sourcing MT-2 in Ireland
Peptides Lab Ireland stocks HPLC-verified MT-2 with per-batch Certificate of Analysis. See the product page. Independent testing by Optima Labs.
Related research guides
- PT-141 (Bremelanotide) Research Reference
- Sexual Health peptides category
- Reconstitution guide
- HPRA regulations
For laboratory research use only. Not intended for human or veterinary use.