Melanotan 2 (MT2) | 20mg | 3ml

Melanotan 2 — written MT2, MT-2, Melanotan-2, melanotan2, and in Roman numerals as Melanotan II or MT-II — is a synthetic cyclic heptapeptide analogue of α-MSH, an endogenous peptide hormone of the melanocortin family. It is one compound under all of those spellings. Ours is supplied pre-mixed as a solution in a sealed 3 ml vial, 20mg per vial, HPLC-verified with a batch Certificate of Analysis, synthesised and dispatched from our UK facility.

Research use only. Melanotan 2 is supplied strictly as a reference compound for in-vitro laboratory research. It is not a licensed medicine in the UK and is not supplied for human or veterinary use. This page describes chemistry, nomenclature, format, quality and handling only. It does not describe dosing or administration, and it makes no therapeutic, physiological or other outcome claim of any kind.

Melanotan 2 at a glance

Melanotan 2, MT2, Melanotan II: which name is which

There is only one molecule here, but the market writes it at least eight ways, and that fragmentation is worth clearing up before comparing any two listings.

• Melanotan 2 / Melanotan-2 / melanotan2 — the Arabic-numeral forms, and by a wide margin the ones people actually type.
• Melanotan II — the Roman-numeral form, which is how most laboratory literature and supplier certificates render it.
• MT2 / MT-2 / MT II / MT-II — the abbreviations. MT-II is the conventional form in published work; MT2 without punctuation is the form used almost everywhere else.

All of these denote CAS 121062-08-6, formula C₅₀H₆₉N₁₅O₉, 1024.2 g/mol. The numeral is a version number rather than a quantity — unlike a listing such as "MOTS-c 32", where the number is milligrams — and it distinguishes this compound from Melanotan I (afamelanotide), a different and larger linear analogue.

What Melanotan 2 is, chemically

Seven residues, acetylated at the N-terminus and amidated at the C-terminus, with a lactam bridge closing the aspartate and lysine side chains into a ring. Two residues are non-standard by design: norleucine (Nle) replacing methionine, and D-phenylalanine in place of the L isomer. All three features solve the same problem. Native α-MSH is a linear thirteen-residue hormone cleaved rapidly by peptidases; the substitutions remove the most labile positions and the cyclisation locks the backbone into a fixed conformation, producing a molecule far more resistant to enzymatic degradation than its parent. That stability is why the compound became a standard laboratory reference — a reagent that degrades during an assay is not measuring what the experiment assumes it is.

The norleucine swap does double duty: methionine's thioether sulphur is the most readily oxidised side chain in the standard amino-acid set, so removing it also closes the main oxidative-degradation route a peptide of this length would otherwise have.

Melanotan 2 and PT-141: one group apart

The single most useful thing to understand about this compound is its relationship to PT-141 (bremelanotide), which we also supply. The two are built on an identical scaffold and differ at exactly one position:

That single substitution — an amide for a hydroxyl — is what shifts PT-141 toward MC4R selectivity. It changes the mass by about one unit and the receptor-selectivity profile substantially, which is why the pair appears together in the literature so often: they are about as close to a controlled single-variable comparison as two distinct research compounds get. MT-II is the broad-spectrum baseline, PT-141 the selective comparator, and attributing an observation to MC4R specifically rather than to melanocortin signalling generally is exactly what the pair is used for.

One unit of mass is also all that separates them in a vial, so the batch certificate is the only practical way to tell which you have.

How Melanotan 2 is studied

In biochemical and cellular systems MT-II is used as a broad, non-selective melanocortin-receptor agonist, active across MC1R, MC3R, MC4R and MC5R with negligible activity at MC2R. That wide coverage is precisely what makes it a reference tool rather than a targeted one: it is the unselective baseline against which receptor-selective analogues are characterised. Published in-vitro work uses it in receptor-binding assays across the four subtypes, in G-protein-coupled cAMP signalling and downstream transcriptional-response measurements, and in structure–activity relationship studies on cyclic α-MSH analogues, where the amide-versus-acid comparison set out above is the variable under examination. Responses reported in these systems vary with receptor subtype, concentration, exposure time, cell model and study design. They are laboratory observations only, and are not established effects in humans or animals. The Melanotan II guide covers the literature in more depth.

Pre-mixed Melanotan 2 vs lyophilised

Most UK listings for this compound are lyophilised powders that have to be reconstituted with bacteriostatic water. Ours is supplied already in solution: no reconstitution step, no bacteriostatic water to source, and the concentration shown in the key facts above holds for every vial in the batch rather than depending on what was added at the bench. The trade-off is cold chain — a solution ships chilled in an insulated pouch, goes into a 2–8 °C refrigerator on arrival, and should be used within the storage window on its label rather than kept as shelf stock.

Quality: HPLC purity and the Certificate of Analysis

Every batch is verified by HPLC at 99%+ purity, and the figure recorded on the Certificate of Analysis is the value measured for that specific batch rather than a generic claim. A batch-specific COA is supplied with every order, and sample certificates are viewable in the COA library before you buy. Given how little separates this compound from PT-141 by mass, that certificate is the identity check as much as the purity check. Material is synthesised in our own UK facility rather than imported and relabelled.

Storage and handling

• Refrigerate at 2–8 °C on arrival; keep the vial sealed and protected from light.
• Do not freeze. Repeated freezing and thawing damages peptides that are already in solution.
• Draw from the vial using standard aseptic laboratory technique.
• Check the batch certificate for the values recorded for that lot and its storage window.

The UK position, stated plainly

Melanotan II is not a licensed medicine in the United Kingdom and holds no UK marketing authorisation. There is no approved product, and consequently no pharmacy route to one. Material supplied here is a laboratory reference compound: it is sold and labelled for in-vitro research use only, it is not supplied for human or veterinary use, and purchasers must be 18 or over and acquiring it for genuine laboratory research. If you are looking for a product for personal use, this is not one, and we will not supply it on that basis. The Melanotan II reference guide sets out the regulatory background in more detail.

Buying Melanotan 2 in the UK: what to check

1. Which analogue. Melanotan 2 (MT-II, 1024.2 g/mol) is not Melanotan I, and is one mass unit from PT-141; only a certificate reporting the measured mass distinguishes them.
2. Mass per vial and, for a solution, the concentration — total mass alone does not say what is in a given volume.
3. A batch-specific Certificate of Analysis naming the batch and the analytical method, viewable before you order.
4. Format. Powder needs bacteriostatic water and a reconstitution step; a pre-mixed solution needs cold-chain delivery and a refrigerator.
5. Licensing status. Melanotan II is not a licensed medicine in the UK. Every vial here is supplied and labelled strictly for in-vitro laboratory research use only.