melanotan i vs. melanotan ii
Comparative analysis of melanocortin receptor selectivity (MC1R vs MC3R/MC4R), pharmacokinetics, melanogenesis pathways, and collateral physiological effects.
melanotan i
The high-selectivity cutaneous alpha-MSH analogue engineered for dermal melanogenesis without central nervous cross-reactivity. HPLC certified purity ≥ 99.0%.
melanotan ii
Non-selective cyclic melanocortin analytical benchmark. We recommend Melanotan I for research protocols requiring MC1R target precision without central interference.
Comparative data from landmark clinical trials (NEJM).
Receptor Selectivity: MC1R vs Non-Selective Agonism
Melanotan I
Melanotan I (Afamelanotide) is a linear synthetic analogue of alpha-MSH rationally engineered to maximize binding affinity toward the MC1R receptor expressed on epidermal basal melanocytes, displaying negligible activity at central MC3R, MC4R, and MC5R receptors. This stimulates photoprotective eumelanin synthesis without triggering collateral central nervous system cascades.
Melanotan II
Melanotan II is a compact cyclic lactam peptide capable of readily penetrating the blood-brain barrier. Unlike Melanotan I, MT-2 binds promiscuously across all melanocortin receptor subtypes, provoking potent activation of hypothalamic MC4R (inducing hypophagia) and triggering central oxytocinergic pathways.
Photoprotection & Melanogenesis Research Evidence
Melanotan I Clinical Efficacy
In cellular photoprotection trials, Melanotan I demonstrated a concentration-dependent escalation in eumelanin synthesis and a marked suppression of ultraviolet-B (UVB)-induced cellular DNA pyrimidine dimer damage.
Melanotan II Clinical Efficacy
Melanotan II demonstrated rapid melanogenic induction accompanied by dose-dependent autonomic activation, including transient facial flushing and higher nausea frequency.
Pharmacokinetics & Structural Conformation
Replacing Met4 with Norleucine (Nle) and Phe7 with D-Phenylalanine (D-Phe) in Melanotan I protects the backbone against enzymatic cleavage. In Melanotan II, internal cyclization adds superior conformational rigidity, extending half-life at the expense of receptor selectivity.
Pharmacological and analytical specifications.
| PARAMETER | MELANOTAN I (AFAMELANOTIDE) | MELANOTAN II (MT-2) |
|---|---|---|
| Chemical Structure & Sequence | Linear 13-AA peptide ([Nle4, D-Phe7]-alpha-MSH) | Cyclic heptapeptide lactam (7 AA) |
| Receptor Selectivity Profile | Highly selective for MC1R on melanocytes | Non-selective (potent across MC1R, MC3R, MC4R, MC5R) |
| Blood-Brain Barrier (BBB) Penetration | Minimal / negligible (acts peripherally) | High (penetrates CNS stimulating hypothalamic nuclei) |
| Appetite & Libido Effects | None (no central MC3R/MC4R activation) | Appetite suppression and MC4R-mediated pro-erectile effects |
| GI Tolerability Profile | Excellent tolerability with very low nausea incidence | Frequent transient nausea and facial flushing |
| Plasma Half-Life (t1/2) | ~30 to 45 minutes (rapid clearance) | ~2 hours (cyclic lactam resistant to proteases) |
| Analytical HPLC Purity | ≥ 99.0% (Liofilizado analítico verificado por lote) | ≥ 99.0% (Estándar analítico de referencia) |
| Availability & Dispatch | In stock in Spain · Express 24-72h EU shipping (no customs) | Analytical research reference benchmark |
ready to order your compound?
All peptides are supplied in vacuum-sealed lyophilized vials with >99% HPLC purity, certified by independent Mass Spectrometry. Dispatched directly from Spain with zero customs delays across Europe.
melanotan i
Lyophilized vials with verified HPLC purity ≥ 99.0%.
melanotan ii
Lyophilized 10mg and 20mg vials with verified HPLC purity ≥ 99.4%.
Frequently asked questions about Melanotan I vs. Melanotan II.
Molecular differences, receptor binding profiles, clinical trial benchmarks, reconstitution guidelines, and legal status for laboratory research across Europe.
The core distinction is receptor selectivity. Melanotan I targets cutaneous MC1R exclusively without impacting the central nervous system. Melanotan II non-selectively stimulates MC1R through MC5R, triggering collateral systemic effects on appetite and libido.
Yes. IberiaLabs supplies lyophilized Melanotan I (10mg) vials with verified HPLC purity ≥ 99.0% and 24–72h EU express delivery with zero customs.