Melanotan 2 Reconstitution Chart (Every Vial Size)

Principles of Reconstituting Lyophilized Melanotan 2

In analytical and preclinical laboratory settings, accurate reconstitutions of lyophilized peptides are essential to ensure reproducible experimental yields and valid assay metrics. Melanotan 2 (MT-II) is typically supplied as a lyophilized powder contained within a sealed, vacuum-evacuated glass vial. Reconstitution requires dissolving this cake in an appropriate sterile liquid diluent to achieve a specific target concentration, measured in milligrams per milliliter (mg/mL) or micrograms per volumetric unit.

When working with a high-purity compound such as Melanotan 2 10mg, precise fluid dynamics and mathematical accuracy prevent volumetric measurement errors. Variable mass quantities and inconsistent diluent volumes will alter the molarity of working solutions, potentially skewing receptor binding data or cellular response curves during in vitro testing. Researchers can utilize our interactive reconstitution calculator to verify custom volumetric equations beyond the standard reference parameters provided in this guide.

The Reconstitution Formula and Variables

Calculating the final concentration of a reconstituted research peptide requires applying basic volumetric mass equations. The fundamental formula for determining concentration ($C$) relies on the mass of the active lyophilized cake ($m$) divided by the total volume of added diluent ($V$):

Concentration (mg/mL) = Mass of Peptide (mg) / Volume of Diluent (mL)

To express the resulting concentration in micrograms per standard volumetric laboratory micro-aliquot (such as 0.1 mL or 100 µL, commonly drawn using a standard 1 mL analytical syringe marked in 100 tick marks or units):

Micrograms per 0.1 mL = (Total Mass in mg / Total Volume in mL) × 100 µg

Because 1 milligram (mg) equals 1,000 micrograms (µg), multiplying the concentration in mg/mL by 100 yields the exact microgram mass contained within a 0.1 mL (10 UI equivalent) volumetric draw.

Worked Example 1: 10 mg Vial Reconstituted with 2.0 mL Diluent

Consider a standard laboratory scenario where a researcher receives a vial containing 10 mg of high-purity lyophilized Melanotan 2 powder and intends to solubilize it with 2.0 mL of Bacteriostatic Water (0.9% benzyl alcohol preserved).

Step 1: Identify the total peptide mass: m = 10 mg. Step 2: Identify the total diluent volume: V = 2.0 mL. Step 3: Calculate mg/mL concentration: 10 mg / 2.0 mL = 5.0 mg/mL. Step 4: Convert to microgram yield per 0.1 mL aliquot: 5.0 mg/mL × 100 µg = 500 µg per 0.1 mL (or 50 µg per 0.01 mL graduation).

In this configuration, every 0.1 mL volume drawn from the vial delivers exactly 500 µg of active Melanotan 2 compound for assay preparation.

Worked Example 2: 10 mg Vial Reconstituted with 1.0 mL Diluent

In assays where a higher working concentration is required—or to minimize working fluid volume in micro-plate applications—a researcher may choose to reconstitute a 10 mg vial with 1.0 mL of diluent.

Step 1: Identify the total peptide mass: m = 10 mg. Step 2: Identify the total diluent volume: V = 1.0 mL. Step 3: Calculate mg/mL concentration: 10 mg / 1.0 mL = 10.0 mg/mL. Step 4: Convert to microgram yield per 0.1 mL aliquot: 10.0 mg/mL × 100 µg = 1,000 µg (1.0 mg) per 0.1 mL.

This higher concentration (10 mg/mL) delivers 100 µg of active peptide per 0.01 mL volumetric tick on an analytical syringe, ideal for concentrated cellular exposure models.

Master Reconstitution Reference Chart

The following master reference table details concentration outputs across common laboratory vial sizes (5 mg, 10 mg, and 20 mg) when paired with standard diluent volumes ranging from 1.0 mL to 3.0 mL.

| Vial Mass (mg) | Diluent Volume (mL) | Resulting Concentration (mg/mL) | Mass per 0.1 mL Aliquot (µg) | Mass per 0.01 mL Unit (µg) | |---|---|---|---|---| | 5 mg | 1.0 mL | 5.0 mg/mL | 500 µg | 50 µg | | 5 mg | 1.5 mL | 3.33 mg/mL | 333 µg | 33.3 µg | | 5 mg | 2.0 mL | 2.5 mg/mL | 250 µg | 25 µg | | 5 mg | 2.5 mL | 2.0 mg/mL | 200 µg | 20 µg | | 5 mg | 3.0 mL | 1.67 mg/mL | 167 µg | 16.7 µg | | 10 mg | 1.0 mL | 10.0 mg/mL | 1,000 µg | 100 µg | | 10 mg | 1.5 mL | 6.67 mg/mL | 667 µg | 66.7 µg | | 10 mg | 2.0 mL | 5.0 mg/mL | 500 µg | 50 µg | | 10 mg | 2.5 mL | 4.0 mg/mL | 400 µg | 40 µg | | 10 mg | 3.0 mL | 3.33 mg/mL | 333 µg | 33.3 µg | | 20 mg | 1.0 mL | 20.0 mg/mL | 2,000 µg | 200 µg | | 20 mg | 2.0 mL | 10.0 mg/mL | 1,000 µg | 100 µg | | 20 mg | 2.5 mL | 8.0 mg/mL | 800 µg | 80 µg | | 20 mg | 3.0 mL | 6.67 mg/mL | 667 µg | 66.7 µg |

This master matrix allows lab technicians to rapidly determine the exact volume required to achieve specific target assay concentrations without manual recalculation during active experiments.

Diluent Selection and Quality Parameters

The choice of reconstitution diluent directly impacts peptide stability, solubility, and contamination risk during laboratory storage. For short-term single-use assays performed immediately upon solubilization, sterile 0.9% Sodium Chloride (Normal Saline) or Sterile Water for Injection (SWFI) may be used. However, because pure sterile water lacks antimicrobial agents, solutions prepared with SWFI undergo rapid degradation and potential bacterial proliferation if stored over extended periods.

For multi-use laboratory protocols requiring stored liquid aliquots, Bacteriostatic Water (sterile water containing 0.9% benzyl alcohol) is the standard industry diluent. Benzyl alcohol acts as a bacteriostatic preservative, inhibiting microbial growth and maintaining solution integrity over multiple draws. All diluents must be evaluated for chemical purity; review PX1's third-party documentation via our certificate of analysis portal to verify that lot-specific purity standards align with your assay requirements.

Standard Operating Procedure: Laboratory Handling & Reconstitution

To prevent peptide denaturation, shearing, or microbial contamination during solubilization, strict aseptic techniques must be observed within a certified laminar flow hood or cleanroom bench.

1. Preparation: Sanitize the rubber stopper of the lyophilized Melanotan 2 vial and the diluent vial with 70% isopropyl alcohol wipes. Allow them to air-dry completely. 2. Pressure Equalization: Draw the desired volume of diluent (e.g., 2.0 mL) into a sterile analytical syringe. Introduce the needle through the stopper center and equalize internal vial pressure as needed. 3. Diluent Transfer: Direct the liquid stream slowly down the inner glass wall of the vial. Never force diluent directly onto the lyophilized cake, as high mechanical force can disrupt the tertiary structure of sensitive peptide chains. 4. Dissolution: Allow the diluent to naturally saturate the powder cake. Gently swirl the vial in a circular motion until fully dissolved. Avoid violent agitation or shaking, which creates foaming and promotes protein denaturation. 5. Inspection: Inspect the solution under bright light. The final liquid must be completely clear, colorless, and free of visible particulates or undissolved flakes.

Preclinical Profile and Receptor Mechanisms of Melanotan 2

Melanotan 2 (Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH2) is a synthetic cyclic heptapeptide analog of naturally occurring alpha-melanocyte-stimulating hormone (α-MSH). In preclinical models, MT-II functions as a potent non-selective agonist across central and peripheral melanocortin receptors, specifically binding to MC1R, MC3R, MC4R, and MC5R.

Researched primarily for its melanocortin activity related to skin pigmentation responses, MT-II activates MC1R on cutaneous melanocytes in animal models, stimulating tyrosinase activity and accelerating eumelanin synthesis. In rodent studies, researchers observe increased cellular melanin density independent of exposure to ultraviolet radiation. Additional preclinical investigations explore MC4R-mediated signaling pathways associated with energy homeostasis, appetite suppression, and neurogenic responses.

Comparative Analysis: Melanotan II vs. Related Melanocortin Agonists

Understanding how Melanotan 2 compares to other synthesized melanocortin analogs is essential for selecting appropriate control compounds in comparative binding and signaling assays.

When designing comparative research protocols, laboratories often evaluate MT-II alongside linear synthetic analogs like Melanotan I (Afamelanotide) and targeted cyclic derivatives like PT-141 (Bremelanotide). While Melanotan I exhibits high specificity for MC1R and a linear structure, Melanotan 2 features a cyclic structure that significantly enhances enzymatic resistance, half-life, and sub-nanomolar binding affinity across both MC1R and MC4R. Conversely, PT-141 is a metabolite derivative optimized for selective central nervous system MC3R and MC4R activation with reduced cutaneous MC1R binding. Exploring broader research categories within our comprehensive peptide research library provides additional structural insights for comparative design.

Storage, Stability, and Quality Assurance Standards

Lyophilized Melanotan 2 powder maintains chemical stability when stored at -20°C in a desiccated freezer environment, protected from light. Under these cold-storage parameters, high-purity lyophilized cakes remain stable for up to 24 months. Following reconstitution with bacteriostatic water, liquid aliquots should be refrigerated at 2°C to 8°C and evaluated within 30 to 60 days to prevent gradual hydrolytic degradation.

At PX1 Research, all research compounds are manufactured in USA-based, GMP-compliant facilities and undergo rigorous lot-by-lot testing. Every lot is verified via High-Performance Liquid Chromatography (HPLC) and Mass Spectrometry (MS) in an independent ISO 17025 accredited laboratory to guarantee greater than 99% purity. Furthermore, bacterial endotoxin testing (LAL assay) ensures that products remain within strict analytical threshold limits suitable for sensitive cell culture and animal studies. For institutional requirements or large-scale project inquiries, explore our dedicated wholesale laboratory portal.