We report net peptide content, not just purity — so the milligrams you dose aren't padded with water and counter-ion. RP-HPLC purity and ESI-MS identity, on a lot-numbered COA.
Net peptide content, not just purity — RP-HPLC + ESI-MS, lot-numbered COA.
Net peptide content on every lot's COA.
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α-MSH analog · approved for erythropoietic protoporphyria
Lyochem primary owner
This Lyochem page is the primary SEO owner for research labs, CROs, and method-development teams qualifying Melanotan I (Afamelanotide) as a documented research-standard lot. The page should answer whether the buyer can review HPLC purity, identity confirmation, lot continuity, stability handling, and assay-fit documentation before ordering.
Overview
Melanotan I (Afamelanotide, brand name Scenesse) is a linear 13-residue synthetic α-MSH analog whose two engineered substitutions, [Nle4, D-Phe7], together confer protease resistance and sharpen selectivity for MC1R over the wider melanocortin-receptor family. That MC1R selectivity is the pharmacological point of difference from Melanotan II: activity is directed to melanocyte pigmentation while sparing the CNS, cardiovascular, and sexual-function effects mediated by MC3R, MC4R, and MC5R. That cleaner receptor profile is what advanced the molecule to regulatory approval by the FDA, EMA, and TGA — a prescription photoprotective agent for the rare metabolic disorder erythropoietic protoporphyria (EPP). Lyochem supplies Melanotan I (Afamelanotide) as a lyophilized reference standard at ≥99.0% HPLC purity. A 13-residue linear chain bearing the non-natural Nle4 and D-Phe7 residues sits in the upper-middle SPPS difficulty range, so the analytical packet pairs peak-integration RP-HPLC with ESI-MS confirmation of the modified mass, and LC-MS/MS sequence verification is available on request; counter-ion and residual-water content are reported as well. Because an approved product exists in several jurisdictions, clinical users should reference the local Scenesse implant, while bulk Afamelanotide is furnished strictly for research and qualified compounding.
Applications & buyer fit
Other research peptides in this category — Melanotan-1, Melanotan-2, PT-141, ACE-031, Adipotide-FTTP, EPO, HCG, HMG — ship to research labs studying topics outside the GH / cognitive / immune / mitochondrial / repair / longevity / Khavinson clusters. Each peptide has its own analytical-packet emphasis (e.g. glycoprotein bioassay in IU/mg for HCG; cyclised-form confirmation for oxytocin) noted in the per-product CoA scope.
Academic Laboratories
Universities, medical schools, and government research institutes qualifying a reference standard for a method-development or in vivo workflow.
Biotech R&D Groups
Preclinical biotech and pharmaceutical discovery teams sourcing characterized peptides for receptor-pharmacology, screening, and method-development campaigns.
Every release ships with its own batch-specific CoA — identity, purity, and the analytical scope agreed at quote stage, tied to the exact lot you receive.
Review a representative batch CoA before you order, so you can confirm the packet matches what your method or sponsor audit needs.
Supplied strictly as a research reagent to research institutions — not a finished dosage form and not for human administration. Buyer qualification runs at the inquiry stage.
Specifications
Documentation available on request
Regulatory note
For erythropoietic protoporphyria, this compound holds prescription-drug approval (Scenesse) across several jurisdictions. We supply it exclusively to qualified buyers holding appropriate licensing in their jurisdiction; for clinical use, reference the locally approved finished product rather than the bulk active.
Selected literature
Frequently asked questions
The two are readily separated by mass. Afamelanotide is the linear 13-residue [Nle4, D-Phe7] analog, whereas Melanotan II is a cyclic seven-residue lactam, so their intact masses differ substantially and ESI-MS alone resolves them. RP-HPLC provides an independent check, since the larger linear sequence and the compact cyclic peptide elute at different retention times against characterized standards. Confirming both the expected mass and the expected chromatographic position on the specific batch prevents mis-identification between the two melanocortin agonists, which is the single most consequential identity question for material sold under either name.
The non-native residues that define this analog, norleucine at position 4 and D-phenylalanine at position 7, are the modifications that give it protease resistance and MC1R-oriented selectivity. Neither substitution changes the intact mass relative to the natural L-Phe and Met parent in a way that mass spec resolves on its own, since D-Phe is a stereoisomer. That makes chromatographic behavior against a qualified reference standard the practical handle: the substituted sequence has a characteristic RP-HPLC retention and purity profile, and matching it confirms the analyst holds the intended [Nle4, D-Phe7] construct rather than a related melanocortin peptide.
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