Melanotan 2 2mg — Vial Spec, Reconstitution Math & COA
Melanotan 2 (MT-II) is a synthetic cyclic heptapeptide melanocortin receptor agonist widely utilized in preclinical research investigating skin pigmentation pathways and melanocortin signaling. A 2mg lyophilized vial format offers research laboratories a specialized, low-mass specification tailored for short-duration assays or initial feasibility trials. PX1 Research delivers analytical-grade research compounds backed by lot-matched HPLC/MS verification and rigorous quality control.
Quick answer
Melanotan 2 (MT-II) is a synthetic cyclic heptapeptide melanocortin receptor agonist widely utilized in preclinical research investigating skin pigmentation pathways and melanocortin signaling. A 2mg lyophilized vial format offers research laboratories a specialized, low-mass specification tailored for short-duration assays or initial feasibility trials. PX1 Research delivers analytical-grade research compounds backed by lot-matched HPLC/MS verification and rigorous quality control.
Key takeaways
- A 2mg vial of [Melanotan](/research-peptides/melanotan-2) 2 contains exactly two milligrams of high-purity, lyophilized Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH2 sequence, formulated as a white to off-white cake or powder without unnecessary filler salts.
- [Melanotan](/research-peptides/melanotan-2) 2 is a synthetic analog of alpha-melanocyte-stimulating hormone (α-MSH).
- Calculating the final working concentration of a 2mg [Melanotan](/research-peptides/melanotan-2) 2 vial depends entirely on the volume of sterile diluent introduced into the sealed reaction vessel.
- Once reconstituted, peptide solutions are susceptible to chemical degradation via hydrolysis, oxidation, and aggregation if subjected to improper temperature fluctuations or repeated physical agitation.
Melanotan 2 2mg Vial Specification & Laboratory Overview
A 2mg vial of Melanotan 2 contains exactly two milligrams of high-purity, lyophilized Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH2 sequence, formulated as a white to off-white cake or powder without unnecessary filler salts. This small-format mass is primarily requested by academic institutions and specialized biotech laboratories running low-volume, single-pass in vitro assays or initial binding affinity screens. By utilizing a 2mg fill size, researchers can eliminate excess reconstituted solution, reducing the potential for peptide degradation across repeated freeze-thaw cycles or prolonged refrigerated storage.
In experimental settings, Melanotan 2 acts as a potent, non-selective agonist across several melanocortin receptor subtypes, including MC1R, MC3R, MC4R, and MC5R. The 2mg format allows precise volumetric control for micro-dosing in microplate assays where minimal reagent volumes are required. It is important to note that while PX1 Research maintains a diverse inventory of research peptides, our primary standardized catalog stock features the larger MTII Melanotan 2 10mg format to maximize cost-efficiency for ongoing bench studies. However, understanding the physical chemistry, reconstitution metrics, and handling protocols for the 2mg specification remains essential for precise laboratory trial design.
Chemical Structure & Melanocortin Receptor Binding Mechanics
Melanotan 2 is a synthetic analog of alpha-melanocyte-stimulating hormone (α-MSH). Structurally, it differs from endogenous α-MSH through a cyclic lactam bridge formed between the side chains of aspartic acid at position 3 and lysine at position 8, along with key amino acid substitutions including D-phenylalanine at position 7 and norleucine at position 4. This structural cyclization confers enhanced conformational stability and resistance to rapid enzymatic degradation by serum proteases compared to linear peptide sequences.
In preclinical model systems, Melanotan 2 exhibits high receptor binding affinity across multiple melanocortin targets. Its activation of MC1R on epidermal melanocytes triggers a signal transduction cascade via G-protein coupled receptors, activating adenylyl cyclase and raising intracellular cyclic adenosine monophosphate (cAMP) levels. This elevation upregulates microphthalmia-associated transcription factor (MITF), which subsequently stimulates the transcription of tyrosinase and related enzymes involved in eumelanin synthesis. Investigating these receptor-ligand dynamics in vitro requires accurate mass measurements and concentration calculations to ensure reproducible experimental outcomes.
Reconstitution Math for a 2mg Vial Format
Calculating the final working concentration of a 2mg Melanotan 2 vial depends entirely on the volume of sterile diluent introduced into the sealed reaction vessel. Because the total mass is fixed at 2000 micrograms (2mg), concentration is inversely proportional to the liquid volume added. Standard laboratory diluents include sterile bacteriostatic water (containing 0.9% benzyl alcohol) or sterile laboratory-grade normal saline.
To achieve target concentrations, researchers can apply simple volumetric dilutions: adding 1.0 mL of diluent yields a final concentration of 2.0 mg/mL (2000 mcg/mL or 2.0 mcg/µL); adding 2.0 mL yields 1.0 mg/mL (1000 mcg/mL or 1.0 mcg/µL); and adding 3.0 mL yields approximately 0.67 mg/mL (666.7 mcg/mL or ~0.67 mcg/µL). For rapid, error-free conversion across varied micro-liter pipette volumes, researchers frequently reference our interactive reconstitution calculator to design accurate assay protocols.
Aliquot Planning and Liquid Handling Protocols
Once reconstituted, peptide solutions are susceptible to chemical degradation via hydrolysis, oxidation, and aggregation if subjected to improper temperature fluctuations or repeated physical agitation. To preserve structural integrity, laboratory protocols generally recommend aliquoting reconstituted Melanotan 2 into single-use microcentrifuge tubes immediately following initial solution homogeneity.
Liquid handling procedures should utilize low-retention, polypropylene pipette tips and sterile polypropylene tubes to minimize non-specific peptide binding to plastic surfaces. Reconstitution diluent should be introduced along the glass wall of the vial, rather than sprayed directly onto the lyophilized cake, followed by gentle swirling. Vortexing or aggressive agitation should be strictly avoided, as shear forces can disrupt secondary structures and accelerate peptide aggregation. Working aliquots should be calculated based on daily assay throughput to avoid re-freezing thawed solutions.
Analytical Quality Verification: Lot-Matched COA Standards
Rigorous research demands absolute certainty regarding compound identity, purity, and mass accuracy. PX1 Research enforces strict quality assurance criteria for every production batch. Prior to release, lot-matched samples undergo high-performance liquid chromatography (HPLC) to verify chemical purity and mass spectrometry (MS) to confirm exact molecular weight.
Every shipped unit corresponds to a batch-specific certificate of analysis, which researchers can review directly via our public COA access directory. Key analytical metrics reported include chromatographic purity percentage (consistently targeting ≥98.0%), primary peak retention time, mass-to-charge ratio (m/z) validation, and bacterial endotoxin testing via Chromogenic Recombinant Factor C or LAL assay methods (maintaining endotoxin levels below strict laboratory safety thresholds, typically <0.01 EU/µg).
Storage Protocols: Lyophilized vs. Reconstituted Stability
Proper temperature control is vital to prevent peptide bond cleavage and deamidation over time. In its dry, lyophilized state, a 2mg vial of Melanotan 2 exhibits robust long-term stability when stored at -20°C or -80°C in a desiccated environment, shielded from direct ultraviolet light exposure. Under these optimal conditions, un-reconstituted lyophilized vials maintain target purity specifications for up to 24 months.
Following liquid reconstitution with bacteriostatic water, working solutions should be stored at 2°C to 8°C for short-term experimental use not exceeding 21–28 days. If reconstituted solutions must be stored for longer periods, aliquots should be immediately deep-frozen at -20°C or -80°C. Avoid standard frost-free freezers, as their automated temperature cycling causes repeated freeze-thaw transitions that break down peptide sequences.
Comparative Vial Sizing: 2mg vs. 10mg Formats
Selecting the appropriate vial mass depends on project scale, assay frequency, and budgetary allocation. While a 2mg vial specification minimizes reagent surplus for isolated bench trials or single-plate binding assays, larger formats offer significant operational advantages for ongoing high-throughput screening or multi-phase animal model studies.
For broader experimental designs, the standard MTII Melanotan 2 10mg format delivers a lower cost-per-milligram, streamlined inventory management, and reduced packaging waste per unit mass. Researchers evaluating broad research programs can review our complete catalog of all peptides to compare available milligram options, purity grades, and physical specifications across our entire research inventory.
Melanocortin Class Comparison: MT-II, MT-I, and PT-141
Melanotan 2 belongs to a broader class of synthetic melanocortin receptor ligands derived from early peptide research into physiological pigmentation pathways. Comparing structural modifications and receptor selectivity profiles across related compounds provides valuable insight for target-specific assay design.
For instance, Melanotan 1 (Afamelanotide) is a linear peptide analog that displays higher selectivity for the MC1R subtype, whereas Melanotan 2 is cyclic and binds broadly across MC1R, MC3R, MC4R, and MC5R. Similarly, PT-141 Bremelanotide, a metabolite derivative of MT-II, features a modified C-terminus designed to shift binding preference toward central MC3R and MC4R pathways while attenuating baseline MC1R activity. In anti-inflammatory and cellular signaling research, smaller sequence fragments such as the tripeptide KPV peptide target distinct downstream nuclear factor kappa B (NF-κB) pathways without inducing melanogenesis, highlighting the diverse functional divergence within the melanocortin peptide family.
Experimental Applications in Preclinical Pigmentation Models
In vitro research applications for Melanotan 2 focus predominantly on dark-type eumelanin production and melanocyte maturation signaling. Cultured human or murine melanocytes exposed to MT-II exhibit dose-dependent increases in intracellular tyrosinase enzyme activity, resulting in elevated melanin content within cellular lysates.
In preclinical animal models, researchers utilize Melanotan 2 to study cutaneous responses to simulated ultraviolet radiation, photoprotective mechanisms, and systemic melanocortin receptor modulation. High-purity compounds are critical in these models to prevent confounding baseline inflammatory responses triggered by trace endotoxins or peptide impurities. Researchers seeking deeper mechanistic data across melanocortin models can explore our expanded research library.
Bulk Procurement and Facility Compliance Standards
PX1 Research operates as a premier USA-based supplier of high-purity research compounds, adhering to rigorous quality management practices across synthesis, lyophilization, analytical testing, and cold-chain packaging. All manufacturing occurs in state-of-the-art, GMP-compliant facilities, with secondary quality verification performed by an independent ISO 17025 accredited analytical laboratory.
Institutional laboratories, university departments, and corporate research facilities managing high-volume screening protocols can access custom fill sizes, specialized packaging formats, and volume discounting through our dedicated wholesale program. Whether utilizing pilot 2mg specifications or standard production-scale batches of Melanotan 2, PX1 Research ensures lot-to-lot consistency and total supply chain transparency.
Frequently Asked Questions
What exact mass of active compound is present in a Melanotan 2 2mg vial?
A Melanotan 2 2mg vial contains exactly 2.0 milligrams (2,000 micrograms) of pure lyophilized Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH2 peptide mass, excluding residual moisture or counter-ions.
How do I calculate working concentrations after adding diluent to a 2mg vial?
To calculate concentration, divide 2.0 mg by the volume of diluent added in mL. For example, 1 mL yields 2.0 mg/mL, 2 mL yields 1.0 mg/mL, and 3 mL yields ~0.67 mg/mL. You can also use the PX1 reconstitution calculator for exact conversions.
Does PX1 Research currently stock the 2mg size or a larger alternative?
PX1 Research primarily stocks the larger, standard MTII Melanotan 2 10mg format in our main catalog for optimal cost efficiency. The 2mg metrics are provided for researchers running pilot or low-volume custom assay calculations.
How is the COA issued for specific Melanotan 2 batch fill sizes?
Every production batch undergoes HPLC, mass spectrometry, and endotoxin testing prior to filling. The resulting certificate of analysis (COA) is lot-matched to the specific bulk synthesis batch, ensuring purity specifications apply universally across all fill sizes.
What is the shelf life of lyophilized Melanotan 2 stored at -20°C?
When stored in its un-reconstituted, desiccated lyophilized form at -20°C or -80°C, Melanotan 2 maintains verified stability and purity for up to 24 months from the manufacturing date.
Why is Melanotan 2 protected from light exposure during laboratory storage?
Melanotan 2 contains aromatic amino acid residues (such as tryptophan and phenylalanine) that can undergo photo-oxidation when exposed to direct light over extended periods, leading to molecular degradation.
How does Melanotan 2 differ from Melanotan 1 in receptor binding affinity?
Melanotan 1 is a linear peptide with higher selectivity for MC1R, whereas Melanotan 2 is a cyclic peptide that exhibits potent, non-selective agonist binding across MC1R, MC3R, MC4R, and MC5R targets.
What endotoxin limits are established for PX1 research peptides?
All PX1 Research peptides undergo endotoxin screening via LAL or recombinant Factor C assays, ensuring endotoxin levels remain under strict laboratory safety standards, typically <0.01 EU/µg.
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