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PeptideSeed supplies research compounds for in-vitro laboratory use only. By entering this site you confirm:
Research use only. Not for human or veterinary consumption. Full terms of supply
Melanotan II is a cyclic heptapeptide analogue of alpha-melanocyte-stimulating hormone, closed by a lactam bridge between the aspartate and lysine side chains.
Melanotan II is a cyclic heptapeptide analogue of alpha-melanocyte-stimulating hormone, closed by a lactam bridge between the aspartate and lysine side chains.
It is a non-selective melanocortin receptor agonist, active across several receptor subtypes - which distinguishes it from PT-141, its C-terminal free-acid metabolite, which shows a different subtype selectivity profile.
The tryptophan residue and the conjugated ring system make it among the more light-sensitive items in the catalogue. Keep vials in opaque packaging throughout handling.
| Compound name | Melanotan II |
| Classification | Specialty research compound |
| CAS number | 121062-08-6 |
| Molecular formula | C50H69N15O9 |
| Molecular weight | 1024.18 g/mol |
| Sequence | Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH2 |
| Purity (this lot) | Pending — per-lot certificate not yet available |
| Endotoxin (this lot) | Pending — per-lot certificate not yet available |
| Appearance | White to off-white lyophilized powder |
| Vial size | 10 mg |
| Solubility | Soluble in sterile water |
| Storage | Lyophilized: -20 C, desiccated, protected from light. Reconstituted: 2-8 C, use within 30 days. |
| Released lot | PS-7423137 |
Vials arrive lyophilized and sealed under nitrogen. Bring the vial fully to room temperature before breaking the seal — opening a cold vial condenses atmospheric moisture onto the cake.
Direct diluent gently against the inside wall of the vial rather than onto the cake, and allow the material to dissolve without agitation. Vortexing shears longer sequences and introduces air.
Lyophilized: -20 C, desiccated, protected from light. Reconstituted: 2-8 C, use within 30 days.
A full walkthrough is in the reconstitution guide, and the calculator will work out concentration and draw volume for this vial size.
Standard laboratory practice applies: appropriate personal protective equipment, no consumption, no administration to humans or animals, and disposal in accordance with institutional protocol and local regulation.
Per-lot laboratory certificate: pending. A reverse-phase HPLC purity report, an LAL bacterial endotoxin assay and a mass-spec identity confirmation for lot PS-7423137 have not been generated or published. PeptideSeed is working directly with its supplier to obtain genuine per-lot documentation and will publish it here, tied to this exact lot number, once it exists. New to reading these? See how to read a certificate of analysis.
Melanotan II is C-terminally amidated; PT-141 carries a free acid. That changes melanocortin receptor subtype selectivity.
A covalent link between the aspartate and lysine side chains that closes the peptide into a ring.
Among the most in the catalogue. Keep it in opaque secondary packaging at all times.
Melanotan II is supplied for in-vitro laboratory research only. It is not a drug, dietary supplement, food or cosmetic, is not approved by the FDA for any use in humans or animals, and no dosing guidance is published for it. Nothing on this page is a therapeutic, structure–function or health claim. Purchasers must be 21 or over and are responsible for compliance with all applicable law. Full terms of supply.
