Melanotan I (MT-1) Raw Material Powder | Cosmetic Skin Tanning Peptide | CAS 121062-08-6

Melanotan I, identified by the Chemical Abstracts Service registry number 121062-08-6 and classified as a linear synthetic peptide with the molecular formula C78H111N21O19, is a specialized raw material supplied as a lyophilized, sterile, white to off-white amorphous powder intended for laboratory research, analytical method development, and the formulation of experimental cosmetic prototypes under controlled conditions. This peptide belongs to the melanocortin family of bioactive molecules and is structurally characterized by its specific amino acid sequence, which distinguishes it from other melanocortin analogs, particularly Melanotan II, due to the absence of a conformational constraint in its backbone architecture, resulting in a more flexible three-dimensional structure when dissolved in aqueous or buffered solutions. As a raw material for research and development, the compound’s physicochemical properties have been thoroughly characterized using standard analytical techniques, with solubility studies confirming that Melanotan I readily dissolves in sterile water, isotonic saline, or slightly acidic buffer solutions at concentrations ranging from 1 to 10 milligrams per milliliter, producing clear, particulate-free solutions when handled under appropriate laboratory conditions. The stability profile of this lyophilized powder is a critical parameter for researchers and formulation scientists, with long-term storage studies demonstrating that the material retains greater than 95 percent of its initial purity when kept desiccated in airtight containers at temperatures below negative twenty degrees Celsius, protected from direct light and humidity, while reconstituted solutions maintained at refrigerated temperatures between two and eight degrees Celsius typically remain stable for periods ranging from seven to fourteen days depending on the sterility practices and container specifications employed during handling. From an analytical quality control perspective, the raw material is routinely subjected to orthogonal characterization methods including reversed-phase high-performance liquid chromatography for purity assessment, mass spectrometry for molecular weight confirmation, and amino acid analysis for compositional verification, with research-grade batches typically achieving purity levels exceeding 98 percent, thereby ensuring that experimental variables arising from synthetic impurities or incomplete deprotection side products are minimized for reproducible laboratory outcomes. The synthesis of Melanotan I is accomplished through solid-phase peptide synthesis strategies utilizing fluorenylmethyloxycarbonyl-protected amino acids, followed by cleavage from the solid support resin, side chain deprotection under acidic conditions, and subsequent purification via preparative reverse-phase liquid chromatography to achieve the high monoisotopic purity demanded by sensitive biological assays and analytical applications. For researchers examining melanocortin receptor interactions, this compound serves as a molecular tool whose binding affinity and selectivity profile have been documented through radioligand binding assays and functional cell-based readouts, with the peptide demonstrating preferential activity at the melanocortin type 1 receptor, a transmembrane G-protein-coupled receptor that initiates intracellular signaling cascades upon ligand engagement. The handling of this raw material in laboratory environments requires standard precautions for working with lyophilized peptides, including the use of lint-free gloves, appropriate respiratory protection when weighing dry powder, and dedicated laminar flow hoods to prevent cross-contamination and environmental release, while any prepared solutions should be filtered through sterile 0.22-micron membrane filters prior to use in cell culture or tissue-based experiments to ensure microbial sterility and remove any particulate matter that may have formed during reconstitution. For formulation scientists exploring the incorporation of Melanotan I into experimental topical delivery systems or other non-systemic cosmetic prototypes, compatibility assessments with common excipients such as buffering agents, preservatives, humectants, and viscosity modifiers are recommended, as certain excipient classes may induce conformational changes in the peptide’s secondary structure as monitored by circular dichroism spectroscopy or fourier-transform infrared spectroscopy, potentially affecting its functional properties in subsequent analytical or biological testing. The peptide’s isoelectric point, determined through isoelectric focusing techniques, indicates its net charge at physiological pH, which influences its solubility profile, aggregation tendency, and potential interactions with charged excipients or delivery vehicle components, all of which are relevant parameters for formulation development work. When designing experiments involving this material, researchers should consider the documented stability boundaries, as exposure to temperatures exceeding forty degrees Celsius, repeated freeze-thaw cycles, or prolonged storage in high ionic strength buffers may accelerate hydrolytic degradation or promote aggregate formation, both of which can be monitored using size-exclusion chromatography or dynamic light scattering as part of routine stability-indicating test methods. The analytical characterization of incoming raw material typically includes the verification of peptide content by amino acid analysis after acid hydrolysis, residual solvent analysis by gas chromatography, and determination of water content by Karl Fischer titration, ensuring that each batch meets predefined specifications for research use. For laboratories performing receptor binding studies, the compound can be radiolabeled with tritium or iodine-125 using established peptide labeling protocols, allowing for quantitative assessment of receptor density and affinity in tissue homogenates or cultured cell systems, provided that appropriate radiation safety procedures are in place. The long-term stability of the lyophilized powder has been evaluated under accelerated conditions according to International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use guidelines for stability testing, with data indicating that the material maintains acceptable purity levels when stored under recommended conditions for extended periods, although users are advised to consult the certificate of analysis for batch-specific storage recommendations. In the context of cosmetic formulation research, the raw material is investigated as an active ingredient for experimental products intended to influence melanin production within the skin through topical application, working through the biological pathway involving the activation of melanocortin receptors located on melanocytes, which subsequently upregulates the enzymatic machinery responsible for melanin biosynthesis. The dose-response characteristics of this peptide in in vitro models using cultured human melanocytes have been established through concentration-response experiments, revealing a sigmoidal relationship with half-maximal effective concentrations typically in the nanomolar range, although inter-individual variability exists due to genetic differences in receptor structure and expression levels. For researchers utilizing cell-based assays, the preparation of stock solutions requires precise weighing of the lyophilized powder using a calibrated analytical balance in a controlled humidity environment, followed dissolution in an appropriate vehicle such as sterile water or dilute acetic acid, with subsequent dilution into cell culture medium to achieve the desired final concentrations while maintaining vehicle concentration below levels known to affect cell viability or baseline melanin production. The material is supplied as a raw chemical intermediate and is not formulated for direct human application, and all research activities involving this compound should be conducted in compliance with applicable institutional guidelines for laboratory chemical safety and ethical research practices. From a documentation perspective, each unit of the raw material is accompanied by a certificate of analysis summarizing the results of quality control tests including purity by high-performance liquid chromatography, identity by mass spectrometry, and quantitative peptide content, providing researchers with the necessary data to reference in their laboratory records and publications. The peptide sequence of Melanotan I has been confirmed through Edman degradation sequencing and tandem mass spectrometry fragmentation patterns, ensuring that the synthetic product matches the intended primary structure without deletions or insertions of extraneous amino acid residues. For formulation development projects involving novel delivery systems such as polymeric nanoparticles, liposomal entrapment, or hydrogel matrices, the compatibility of Melanotan I with the chosen formulation components should be evaluated through forced degradation studies followed by chromatographic analysis to detect any peptide-excipient interaction products that may form during processing or storage. The raw material’s solubility in various solvents has been systematically evaluated, with data indicating good solubility in water and dilute acetic acid, limited solubility in ethanol, and very low solubility in nonpolar organic solvents such as hexane or chloroform, information that is valuable for selecting appropriate vehicles for different experimental applications. When reconstituting the lyophilized powder for use, it is generally recommended to allow the vial to equilibrate to room temperature prior to opening to minimize moisture condensation on the cold powder, followed by the addition of the chosen solvent directly onto the powder cake with gentle swirling rather than vigorous shaking to avoid foaming and potential denaturation at the air-water interface. For quality control laboratories performing routine analysis of this raw material, established high-performance liquid chromatography methods utilizing reversed-phase columns with C18 stationary phases and gradient elution with acetonitrile-water-trifluoroacetic acid mobile phases have been validated for specificity, linearity, accuracy, and precision, providing a reliable platform for purity assessment. The reference standard material used for quantitative analysis can be prepared from the same batch of highly purified peptide and characterized through orthogonal techniques to establish its purity value, against which subsequent batches can be calibrated. In summary, Melanotan I (CAS 121062-08-6) is a well-defined synthetic peptide raw material supplied as a high-purity lyophilized powder with documented physicochemical properties, stability characteristics, and analytical specifications, making it suitable for laboratory research, analytical method development, and experimental cosmetic formulation work when handled according to standard laboratory practices and stored under recommended conditions.