Melanotan I (Afamelanotide) | CAS 75921-69-6 | MC1R Agonist (Research Use Only) | Knowlux

Product Description

Melanotan I, CAS 75921-69-6, is a synthetic 13-amino-acid peptide analogue of alpha-melanocyte-stimulating hormone (alpha-MSH) supplied by Knowlux for laboratory research use. It is also known as afamelanotide, NDP-MSH, or CUV1647. The molecular formula is C78H111N21O19 and the molecular weight is 1646.85 g/mol (free peptide basis). Each lot is released with a lot-specific COA, MSDS and full analytical traceability.

CAS and form clarification: CAS 75921-69-6 is consistently recorded across ChemicalBook, PeptideDB and 001Chemical as Melanotan I / afamelanotide (free peptide). A separate CAS, 1566590-77-9, is frequently listed in commercial channels as an alternative identifier for Melanotan I acetate, but this CAS is recorded in USAN documentation as afamelanotide acetate and should be confirmed with the supplier before purchase. Knowlux supplies the free peptide form and declares the counter-ion and assay basis on each COA. Afamelanotide is approved by the FDA (Scenesse, 2019) and EMA (2014) as a subcutaneous implant for phototoxicity prevention in erythropoietic protoporphyria (EPP); that approval is specific to the finished pharmaceutical product and does not extend to this research-grade supply.

Product Parameters

Product Details

1. Overview

Melanotan I (afamelanotide) is a linear 13-amino-acid analogue of alpha-MSH, modified by substitution of norleucine at position 4 and D-phenylalanine at position 7. These modifications confer resistance to enzymatic degradation and increase receptor affinity relative to the native hormone, extending its biological half-life to approximately 30 minutes. The peptide acts as an agonist at the melanocortin-1 receptor (MC1R) on melanocytes, stimulating eumelanin synthesis independently of UV exposure. It is approved as a subcutaneous implant (Scenesse) for the prevention of phototoxicity in adult patients with erythropoietic protoporphyria (EPP). Knowlux supplies Melanotan I as a research-grade peptide for laboratory and analytical use; this supply is not intended for human administration and does not constitute a finished drug product.

2. Mechanism of Action (Research Context)

Published research describes Melanotan I as a non-selective melanocortin receptor agonist, with reported Ki values of 0.085 nM (MC1R), 0.4 nM (MC3R), 3.8 nM (MC4R) and 5.1 nM (MC5R), indicating preferential activity at MC1R. Activation of MC1R on melanocytes stimulates the cAMP/PKA pathway, upregulates MITF, and promotes eumelanin synthesis and melanosome transfer to keratinocytes. Beyond pigmentation, MC1R activation is reported to increase antioxidant activity, DNA repair, and secretion of immunomodulatory proteins such as interleukin-10. These descriptions are derived from published research and are provided for scientific reference only. Knowlux makes no claims regarding the efficacy, safety, or suitability of this product for any human application. Promotion of Melanotan I for tanning, photoprotection, or any clinical indication is not supported by Knowlux and is inconsistent with research-use-only supply.

3. Quality Control

4. Applications

• Reference standard for melanocortin receptor agonist analytical method development

• MC1R binding and functional assay development

• Melanogenesis and melanocyte biology research models

• Photoprotection and DNA repair research models (investigational)

• Comparative studies of Melanotan I vs Melanotan II receptor selectivity

• LC-MS and immunoassay calibrators

5. Packaging, Storage & Shipping

Lyophilized powder: amber glass vial under nitrogen headspace, sealed with butyl stopper and aluminium crimp. Secondary packing: tamper-evident, light-protected carton with desiccant. Cold-chain shipping with validated gel packs and temperature logger; dry ice for -20 C shipments. COA, MSDS, packing list and certificate of origin issued with each shipment.

6. Documentation Support

Per lot: COA, MSDS, certificate of origin, residual solvent statement, counter-ion specification, intact-mass spectrum, MT-I/MT-II separation report. Regulatory packages (specification summaries, audit support) available on a project basis.

About Knowlux

Knowlux Biotechnology is a GMP-oriented manufacturer and supplier of peptides, APIs and fine-chemical research compounds, operating from Hubei, China. We serve research groups, CDMOs and distributors in more than 40 countries, and support contract synthesis, custom packaging and technical documentation requests.

Compliance Statement

This product is supplied for laboratory research use only. It is not for human or animal administration, not for diagnostic or therapeutic use, not for retail sale, and not for personal use. Afamelanotide is approved as a prescription medicine (Scenesse) by the FDA (2019) and EMA (2014) for phototoxicity prevention in erythropoietic protoporphyria; that regulatory status is specific to the approved pharmaceutical product and does not extend to this research-grade supply as sold by Knowlux. Melanocortin-active peptides are addressed by anti-doping frameworks, including provisions covering non-approved substances and peptide hormones and their mimetics; supply chains touching athlete populations require additional attestations and end-use screening. Research context statements are for scientific reference only and do not constitute medical advice, promotional claims, or dosing guidance.