MT-2 (Melanotan II)

About This Research Material

This listing supplies MT-2 (Melanotan II) as a lyophilized reference material for in-vitro and preclinical laboratory work. MT-2 is a synthetic cyclic heptapeptide analog of alpha-melanocyte-stimulating hormone (alpha-MSH), with the molecular formula C50H69N15O9 and CAS number 121062-08-6. Its defining structural feature is a lactam bridge that cyclizes the peptide backbone; this constraint holds the molecule in a conformation that laboratory studies report to be more resistant to enzymatic degradation than the linear native hormone, which is one reason MT-2 is frequently selected as a stable model ligand in melanocortin-receptor research. The material is produced synthetically and characterized as a discrete, sequence-defined heptapeptide rather than as an extract or blend.

In the literature MT-2 is classified as a non-selective melanocortin receptor agonist, meaning it engages several members of the melanocortin receptor family (notably MC1R, MC3R, MC4R, and MC5R) rather than a single subtype. That broad receptor engagement is why it is often used as a reference tool compound by researchers studying melanocortin signaling in cell-based systems. All descriptions below concern the research substance itself — its documented study history, its analytical fingerprint, and standard handling of freeze-dried peptide reference material — and are not statements about outcomes in humans or animals.

What Has Been Studied in Preclinical Models

Published investigations involving MT-2 are predominantly receptor-pharmacology and cell-based in nature, using it as a reference agonist to study how the melanocortin receptor family transduces signals. Because it activates multiple receptor subtypes, it appears in assays measuring cyclic AMP (cAMP) accumulation and receptor binding across MC1R–MC5R constructs expressed in cultured cell lines. It is also cited in melanogenesis studies using cultured melanocyte and melanoma cell models, where researchers examine tyrosinase-related endpoints and pigment-pathway signaling in vitro under controlled conditions.

• cAMP-accumulation and radioligand-binding assays characterizing agonist activity at MC1R, MC3R, MC4R, and MC5R constructs.
• In-vitro melanogenesis and tyrosinase-pathway studies in cultured melanocyte and melanoma cell lines.
• Structure–activity comparisons against native alpha-MSH and other cyclic melanocortin analogs to map receptor selectivity.
• Enzymatic-stability and conformational studies exploiting the lactam-bridged cyclic backbone as a degradation-resistant scaffold.

Analytical Characterization

Each research lot is supplied as a lyophilized powder at a stated peptide mass of 10 mg per vial and is characterized before release to a purity of at least 99%. Identity and purity are established using orthogonal analytical methods so that the material on the Certificate of Analysis (COA) matches the sequence and mass expected for the cyclic heptapeptide. This dual-method approach separates purity (how much of the sample is the target peptide) from identity (confirmation that the target is the correct molecule).

• RP-HPLC purity: quantified by peak-area integration and reported on the COA (≥99%). The chromatogram resolves the main peak from process-related impurities, truncated sequences, and any uncyclized linear precursor.
• Mass-spectrometry identity: ESI-MS or MALDI-TOF confirms the observed mass against the theoretical value calculated for C50H69N15O9, verifying that the lactam-cyclized molecule is present rather than an open-chain analog.
• Supporting data: appearance, net peptide content, and water-content or residual-solvent checks where applicable.

The COA accompanying each product is the definitive analytical record for that specific lot. Because purity and mass can vary slightly between synthesis batches, researchers should reference the COA tied to the lot number received rather than generic specifications when documenting experimental inputs. Retaining the COA alongside experimental records supports reproducibility and traceability.

Laboratory Handling of Lyophilized Material

As a lyophilized peptide, MT-2 is hygroscopic and sensitive to repeated temperature cycling. Standard laboratory practice is to allow sealed vials to equilibrate to room temperature before opening to minimize condensation, then reconstitute with an appropriate research-grade solvent under aseptic technique. Aliquoting reconstituted stock into single-use portions limits freeze-thaw cycles that can degrade peptide integrity, and protecting solutions from prolonged light exposure is prudent for melanocortin peptides. Detailed temperature and stability windows for lyophilized, reconstituted, and working solutions appear in the storage table on this page. All handling guidance refers to laboratory management of the material and does not describe or imply any use in humans or animals.