Overview
In plain English
Melanotan II is a synthetic cyclic analogue of alpha-melanocyte-stimulating hormone, the hormone that signals melanocytes to produce pigment. It was developed at the University of Arizona.
It is studied in published research as a non-selective melanocortin receptor agonist: MC1R-mediated melanogenesis, and central MC3R/MC4R signalling. It is not an approved medicine in any jurisdiction. Strictly for laboratory research use. Not for human or veterinary consumption.
- What it isA cyclic lactam analogue of alpha-melanocyte-stimulating hormone
- Mainly studied forMC1R-mediated melanogenesis and central melanocortin receptor signalling
- Supplied asLyophilised powder, 10mg vial, independently assayed
How it works
What it actually does
Melanocytes carry a receptor, MC1R, that switches on pigment synthesis when activated. Melanotan II activates it — and it is a far more durable molecule than the native hormone, which is degraded almost immediately in circulation.
The defining caveat: it is not selective. The same receptor family includes the central MC3R and MC4R, which govern energy balance and other hypothalamic signalling, so a single molecule engages several circuits at once.
It is not approved as a medicine in any country, and the published case-report literature describes adverse events following unregulated use — one reason more selective analogues were later developed.
The science in detail
Melanotan II is a synthetic analogue of alpha-melanocyte-stimulating hormone, developed at the University of Arizona from structure-activity work on the alpha-MSH core sequence. The native hormone is rapidly degraded and has little utility as a research probe. Two modifications address this. First, substitution of the L-phenylalanine at position 7 with its D-enantiomer confers resistance to proteolysis and increases potency. Second, a lactam bridge between an aspartate and a lysine side chain constrains the backbone into a cyclic conformation that approximates the bioactive shape of the native ligand, raising affinity considerably.
The melanocortin system comprises five G-protein-coupled receptors. MC1R is expressed on melanocytes and couples to adenylate cyclase; agonism raises cAMP, activates protein kinase A and increases transcription of microphthalmia-associated transcription factor, which in turn drives tyrosinase expression and the eumelanin synthesis pathway. MC3R and MC4R are predominantly central, concentrated in hypothalamic nuclei governing energy balance, and MC4R signalling is also implicated in other central autonomic pathways. MC2R responds to ACTH in the adrenal cortex, and MC5R is associated with exocrine function.
Melanotan II is non-selective across this family. That is the defining pharmacological property of the compound and the reason its research profile is so broad: a single molecule engages pigmentary and central hypothalamic circuits simultaneously. It is also the reason findings are difficult to attribute to any one receptor, and the reason more selective analogues were subsequently developed — bremelanotide, an MC4R-weighted derivative, emerged from this line of work.
The human literature is small and early-phase. Dorr et al. (Life Sciences, 1996) reported a pilot phase I evaluation describing pigmentary responses alongside a characteristic set of adverse effects. Wessells et al. (Journal of Urology, 1998) conducted a double-blind, placebo-controlled crossover study of central melanocortin-mediated responses.
Melanotan II is not approved as a medicine in any jurisdiction, and case reports in the dermatological literature describe adverse events following unregulated use. Purist supplies it strictly as a laboratory reference compound.
Evidence
What the research shows
Activates the melanocyte pigment pathway
It agonises MC1R, which switches on tyrosinase and eumelanin synthesis in published models.
Built to resist degradation
Two structural changes make it resist breakdown and bind far more strongly than the native hormone.
Not selective — that is the trade-off
It also engages the central MC3R and MC4R, which is why findings are hard to attribute to any one receptor.
Not an approved medicine anywhere
Supplied as a research reference compound. Case reports describe adverse events following unregulated use.
Reconstitution & handling
Reconstitution and handling in the laboratory
These are general handling notes for the lyophilised peptide supplied by Purist Peptides. They describe the preparation of a stock solution for laboratory work. They are not a dosing protocol, and they describe no administration to a person or an animal.
A 3ml vial of bacteriostatic water is included free with every peptide vial you order, so the material can be reconstituted on arrival.
Melanotan II 10mg — preparing a stock solution
Choice of diluent
Bacteriostatic water (water for injection with 0.9% benzyl alcohol) is the usual diluent where a stock will be drawn from repeatedly, because the preservative permits several septum entries across a working period. Sterile water for injection and sterile 0.9% sodium chloride are both used where a single-use preparation is wanted instead. The diluent volume sets the concentration of the stock, so record it.
Sterile technique
- Allow the sealed vial to reach room temperature before opening the carton — reconstituting a cold lyophilised cake slows dissolution
- Work in a clean area or a laminar flow cabinet, and wipe the rubber septum with 70% isopropyl alcohol, letting it dry fully
- Draw the chosen volume of diluent using a sterile single-use syringe and needle
- Angle the needle so the diluent runs down the inside wall of the vial — do not direct the stream onto the lyophilised cake
- Roll the vial gently between the palms until the cake has dissolved completely. Do not shake and do not vortex: peptides are surface-active, and agitation drives foaming and aggregation
- Let the vial stand for 5 to 10 minutes. A correctly reconstituted solution is clear and free of visible particles
Working out the concentration
Concentration follows from the mass in the vial and the volume of diluent added, nothing else. Adding 2ml of diluent to the 10mg vial gives a 5mg/ml stock; adding 1ml gives 10mg/ml. Label every reconstituted vial with its concentration and the date it was prepared.
Storage and stability
Before reconstitution
The lyophilised powder is the stable form. Sealed vials are best held at −20°C, protected from light and from moisture; the short periods at 2 to 6°C that occur in transit and on arrival are expected and are accounted for in the supply chain. Keep the vial in its carton — light and humid air are the two ordinary causes of loss on storage.
After reconstitution
Hold reconstituted solution at 2 to 6°C and protect it from light. Do not freeze a working stock: freeze-thaw cycling is the main avoidable cause of degradation and of visible precipitate. Where material must be held beyond a short working period, aliquot the stock into sterile low-binding tubes and freeze the aliquots once at −20°C or below, thawing each aliquot only once.
Checks before use
Inspect every vial against a light source. Discard any solution that is hazy, discoloured or contains particles, and any vial whose septum integrity is in doubt. The independent HPLC assay report for the batch supplied is available on request.
Strictly for laboratory research use. Not for human or veterinary consumption.
Questions
Frequently asked questions
What has Melanotan II been investigated for?
Published research covers MC1R-mediated melanogenesis and central melanocortin signalling in energy balance and other hypothalamic pathways. Human data are limited to early-phase studies including Dorr et al. (Life Sciences, 1996) and Wessells et al. (Journal of Urology, 1998).
What does non-selective mean in this context?
Melanotan II binds and activates several melanocortin receptor subtypes rather than one. A single molecule therefore engages pigmentary and central hypothalamic circuits at once, which makes attributing any observed effect to a specific receptor difficult in experimental work.
How does it differ from bremelanotide?
Bremelanotide is a later derivative weighted towards MC4R activity, developed to separate central effects from MC1R-mediated pigmentary signalling. Melanotan II remains the non-selective parent compound and is used in research primarily as a broad melanocortin reference agonist.
Is Melanotan II an approved medicine?
No. It is not approved for human use in any jurisdiction, and dermatological case reports describe adverse events following unregulated use. Purist supplies it exclusively as a laboratory reference compound for in vitro and preclinical research.
How is purity verified?
Every batch is assayed by independent HPLC at Bioindustrial Services in Boksburg. We do not rely on the manufacturer's own certificate alone. The assay report for the batch you receive is available on request, and our full testing protocol is set out at Quality Standards.
How long does delivery take?
Orders are dispatched from South Africa, with timelines varying by region and courier. Current dispatch and transit windows are set out at Delivery Process.
What is the returns policy?
Unopened vials in original condition may be returned under the conditions set out at Refund Policy.
Ready to order Melanotan II?
Independently assayed to 99%+ purity. Research use only.
Add to cart — R 400.00The Purist Research Standard
Precision-engineered peptides designed to maintain structural integrity under rigorous laboratory conditions.
Optimized Logistics & Fulfillment
Our logistics and fulfillment protocols are engineered to prioritize research stability.
≥99% Research-Grade Purity
Every compound is synthesized to exceed a 99% purity threshold.
Third-Party Laboratory Verified
We maintain total transparency through independent COA.
Precision Lyophilization Technology
Our advanced flash-freeze and vacuum-drying process.
Controlled Synthesis Environment
Produced in sterile, ISO-compliant facilities.
Targeted Research Utility
Engineered as reliable biological models.
Recommended Products
Essential Compounds for Precision Research: Top-Tier Peptides Verified for Structural Integrity.
Testimonials
Real feedback from customers who prioritize purity, precision, and uncompromising quality standards.
