Melanotan 2 FAQ: Sourcing, Purity, Storage & Shipping
This technical reference guide provides researchers with comprehensive specifications regarding Melanotan II (MT-II) handling, sourcing, and purity verification. Designed strictly for laboratory investigation, PX1 Research supplies high-purity synthetic peptides backed by lot-specific analytical documentation.
Quick answer
This technical reference guide provides researchers with comprehensive specifications regarding Melanotan II (MT-II) handling, sourcing, and purity verification. Designed strictly for laboratory investigation, PX1 Research supplies high-purity synthetic peptides backed by lot-specific analytical documentation.
Key takeaways
- [Melanotan](/research-peptides/melanotan-2) II (MT-II) is a synthetic cyclic heptapeptide analog of alpha-melanocyte-stimulating hormone (α-MSH).
- [Melanotan](/research-peptides/melanotan-2) II has the amino acid sequence Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH2 and a molecular weight of 1024.2 g/mol.
- Analytical verification of laboratory peptides requires multi-modal instrumentation to confirm identity, purity, and safety for cell culture and tissue assays.
- When designing melanocortin receptor research, selecting the appropriate agonist peptide is critical for isolated signal transduction studies.
Melanotan II Preclinical Overview & Receptor Binding
Melanotan II (MT-II) is a synthetic cyclic heptapeptide analog of alpha-melanocyte-stimulating hormone (α-MSH). In preclinical models, MT-II functions as a non-selective agonist across multiple central and peripheral melanocortin receptor subtypes, including MC1R, MC3R, MC4R, and MC5R. The compound features a lactam bridge structure that imparts enhanced enzymatic resistance and prolonged binding affinity compared to native endogenous MSH peptides.
Primary in vitro and animal study models examine MT-II for its influence on melanogenesis and skin pigmentation responses through MC1R activation, as well as central metabolic and neural signalling pathways mediated via MC3R/MC4R. Researchers studying melanocortin signaling pathways utilize our highly purified Melanotan II 10mg vials to ensure reproducible baseline binding kinetic measurements.
Chemical Identity, Sequence, and Purity Standards
Melanotan II has the amino acid sequence Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH2 and a molecular weight of 1024.2 g/mol. PX1 Research synthesizes MT-II via automated solid-phase peptide synthesis (SPPS) in ISO 17025 accredited and GMP-compliant facilities within the United States. This process minimizes sequence truncation and side-chain oxidation artifacts.
To evaluate chemical integrity, every production lot undergoes rigorous quality control. Researchers seeking full transparency across our product catalog can review detailed analytical reports within our searchable certificate of analysis database. Every lot must meet or exceed a minimum chemical purity threshold of 99.0% by high-performance liquid chromatography (HPLC).
Analytical Verification: HPLC, Mass Spectrometry, and Endotoxin Testing
Analytical verification of laboratory peptides requires multi-modal instrumentation to confirm identity, purity, and safety for cell culture and tissue assays. High-Performance Liquid Chromatography (HPLC) verifies that no significant peptide impurities or synthesis byproducts remain in the final lyophilized powder.
Simultaneously, Mass Spectrometry (MS) confirms the precise molecular mass of 1024.2 Da, ensuring correct cyclization and sequence fidelity. In addition, chromogenic LAL assays are conducted on every batch to confirm endotoxin levels remain below 0.05 EU/mg, preventing cellular toxicity or confounding inflammatory artifacts in sensitive bioassays.
Comparative Analysis: Melanotan II vs. Related Melanocortin Compounds
When designing melanocortin receptor research, selecting the appropriate agonist peptide is critical for isolated signal transduction studies. Melanotan II demonstrates broad receptor non-selectivity with high potency at MC1R and MC4R.
By contrast, linear analogs such as Melanotan 1 exhibit distinct receptor selectivity profiles, while specialized derivatives like PT-141 Bremelanotide are selected for investigation into central neuro-pathways without primary MC1R skin pigmentation responses. Researchers exploring broader peptide classes can also inspect non-melanocortin cellular signaling tools within our complete catalog of research peptides.
Reconstitution Guidelines for Laboratory Applications
Melanotan II is supplied as a sterile, lyophilized white powder sealed under inert gas. For in vitro assay preparation, the cake must be reconstituted using sterile Bacteriostatic Water (0.9% benzyl alcohol) or sterile laboratory-grade saline, depending on the requirements of the specific cell culture model.
To ensure precise molar calculations and avoid concentration errors during dilution series, investigators are encouraged to utilize our interactive reconstitution calculator tool. Proper technique involves directing the solvent stream down the inner glass wall of the vial rather than directly onto the lyophilized cake, followed by gentle swirling without vigorous agitation.
Stability and Short- vs. Long-Term Storage Conditions
Lyophilized Melanotan II exhibits excellent chemical stability when stored in dark, desiccated conditions. For long-term storage prior to reconstitution, vials should be maintained at -20°C or -80°C, where the peptide remains stable for up to 24 months without noticeable degradation.
Once reconstituted into aqueous solution, MT-II should be aliquoted into single-use polypropylene tubes to prevent repeated freeze-thaw cycles. Reconstituted solutions stored at 2°C to 8°C maintain structural stability for up to 30 days, provided sterile technique is maintained and exposure to light is minimized.
Packaging, Cold Chain, and USA Dispatch Standards
PX1 Research packages all peptides in climate-controlled environments using borosilicate glass vials with rubber stoppers and aluminum crimp seals to preserve vacuum integrity during transit. Orders are dispatched directly from primary distribution hubs in California and Arizona.
All orders placed Monday through Friday before 12:00 PM PST feature same-day dispatch. Lyophilized peptides are highly resilient to short-term ambient temperature fluctuations encountered during standard transit, though thermal protection packaging is utilized during peak summer months.
Institutional Sourcing, Wholesale Accounts, and Quality Assurances
Academic institutions, contract research organizations (CROs), and corporate biotechnology laboratories require consistent lot-to-lot repeatability and volume availability. PX1 Research provides dedicated enterprise ordering pathways for high-volume research programs.
Principal investigators and laboratory managers can review our dedicated wholesale research procurement hub to set up standing orders, request customized vial sizes, or obtain raw HPLC/MS raw data files. Explore additional technical documentation across our site research library.
Frequently Asked Questions
What is Melanotan II and what is its primary mechanism in laboratory research?
Melanotan II (MT-II) is a synthetic cyclic heptapeptide analog of alpha-melanocyte-stimulating hormone (α-MSH). In preclinical laboratory models, it acts as a potent agonist across melanocortin receptors MC1R, MC3R, MC4R, and MC5R, and is primarily researched for melanocortin activity related to skin pigmentation responses and central metabolic signalling.
What is the physical appearance and molecular weight of Melanotan 2?
Melanotan II is supplied as a lyophilized white to off-white cake or powder. It has a chemical formula of C50H69N15O9 and a verified molecular weight of 1024.2 g/mol.
Is Melanotan 2 approved for human or clinical use?
No. Melanotan II supplied by PX1 Research is strictly designated for laboratory research use only (in vitro and preclinical animal research). It is not approved for human consumption, clinical use, or veterinary administration.
How is the purity of PX1 Research Melanotan II verified?
Every lot of Melanotan II undergoes independent analytical testing using High-Performance Liquid Chromatography (HPLC) to confirm purity ≥99.0% and Mass Spectrometry (MS) to confirm sequence mass identity.
Where can I view the lot-specific COA for Melanotan 2?
Lot-specific Certificates of Analysis (COAs), including raw HPLC chromatograms and MS spectra, are publicly available and downloadable directly from our online COA database.
What are the endotoxin thresholds for PX1 Research Melanotan 2?
Each batch of MT-II is screened via chromogenic Limulus Amebocyte Lysate (LAL) testing to ensure endotoxin levels remain strictly below 0.05 EU/mg, protecting cell cultures from inflammatory interference.
What vial sizes are available for Melanotan 2?
PX1 Research offers Melanotan II in standard 10mg lyophilized glass vials, fitted with crimped flip-off seals to preserve product vacuum and sterility.
How should lyophilized Melanotan 2 be stored upon arrival?
Unopened, lyophilized vials should be stored at -20°C for medium-term research or -80°C for long-term preservation. Store in a dark, dry environment away from light.
How long is reconstituted Melanotan 2 stable in solution?
Once reconstituted with sterile bacteriostatic water, MT-II solution remains chemically stable for up to 30 days when kept refrigerated between 2°C and 8°C.
What diluent should be used to reconstitute Melanotan 2 for in vitro research?
Reconstitution is typically performed using sterile Bacteriostatic Water (0.9% benzyl alcohol) or sterile 0.9% Sodium Chloride, depending on cell line sensitivity and assay parameters.
How do I calculate precise liquid concentration after reconstitution?
Researchers can utilize the PX1 interactive Reconstitution Calculator tool by entering total peptide mass (e.g., 10mg) and added diluent volume (e.g., 2mL) to determine exact concentration per unit volume.
Can reconstituted Melanotan 2 undergo multiple freeze-thaw cycles?
No. Repeated freeze-thaw cycles cause peptide aggregation and molecular degradation. Reconstituted liquid should be divided into single-use aliquots before freezing.
Where are PX1 Research peptides synthesized and shipped from?
All PX1 Research compounds are synthesized in state-of-the-art USA facilities and dispatched directly from primary fulfillment centers located in California and Arizona.
What are the shipping options and dispatch timelines?
PX1 Research provides same-day dispatch for orders placed before 12:00 PM PST Monday through Friday. Standard and expedited courier services are selectable during checkout.
Does ambient heat during shipping degrade lyophilized Melanotan 2?
Lyophilized synthetic peptides are structurally stable at ambient room temperatures for up to 14 days during transit. Cold packs are included during high-temperature shipping conditions.
How does Melanotan II differ from Melanotan I in preclinical studies?
Melanotan I (Afamelanotide) is a linear peptide agonist with higher relative selectivity for MC1R, whereas Melanotan II is a cyclic analog with broader potency across MC1R, MC3R, MC4R, and MC5R.
What solvent handling technique prevents peptide damage during reconstitution?
Direct high-pressure solvent streams can break down peptide structures. Always aim the needle at the inner vial wall, allowing diluent to slowly flow down, followed by gentle swirling.
Can institutional buyers request bulk or custom wholesale packaging for Melanotan 2?
Yes. Institutional researchers, CROs, and university laboratories can submit bulk quotes through our wholesale portal for custom vial quantities, specialized aliquoting, or raw powder orders.
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All products are sold strictly for laboratory and research use only. Not for human or veterinary use, diagnosis, treatment or consumption. Statements have not been evaluated by the FDA.