Melanotan I vs Melanotan II

Compare Melanotan I and Melanotan II, two melanocortin peptides with different receptor selectivity profiles. Understand how structural differences translate to distinct research applications.

Peptide A

Melanotan I

Sexual Health / Hormonal

From
$34.95
≥99% Purity1646.87 Dat\u00BD: ~30 minutes to 2 hours
View Melanotan I details
Peptide B

Melanotan II

Sexual Health / Hormonal

From
$34.95
≥99% Purity1024.18 Dat\u00BD: ~33 minutes
View Melanotan II details

Side-by-Side Comparison

Mechanism
Melanotan I

Linear alpha-MSH analog with Nle4/D-Phe7 substitutions; selectively activates MC1R on melanocytes via cAMP/PKA pathway to upregulate tyrosinase and increase eumelanin production

Melanotan II

Non-selective cyclic melanocortin receptor agonist activating MC1R, MC3R, MC4R, and MC5R; produces simultaneous tanning, sexual arousal, appetite suppression, and fat mobilization

Receptor Targets
Melanotan I

Primarily MC1R (melanocortin 1 receptor) — selective for pigmentation

Melanotan II

MC1R + MC3R + MC4R + MC5R — broad melanocortin activation

Half-Life
Melanotan I

~30 minutes to 2 hours

Melanotan II

~33 minutes

Dosing Frequency
Melanotan I

Typically studied daily during loading, then maintenance

Melanotan II

Typically studied daily during loading, then as needed

Purity
Melanotan I

\u226599% (HPLC verified at 99.8%)

Melanotan II

\u226599% (HPLC verified at 99.7%)

Research Applications
Melanotan I

Photoprotection and UV damage prevention, melanogenesis and tanning mechanisms, erythropoietic protoporphyria (approved in EU as Scenesse), skin cancer prevention, melanocortin receptor selectivity

Melanotan II

Skin pigmentation and tanning, sexual function and arousal (MC4R), appetite suppression and feeding behavior, melanocortin receptor pharmacology, body composition effects

Molecular Weight
Melanotan I

1646.87 Da (13 amino acids, linear)

Melanotan II

1024.18 Da (7 amino acids, cyclic)

Starting Price
Melanotan I

$34.95/vial (10mg)

Melanotan II

$34.95/vial (10mg)

Detailed Breakdown

Mechanism

Melanotan I

Linear alpha-MSH analog with Nle4/D-Phe7 substitutions; selectively activates MC1R on melanocytes via cAMP/PKA pathway to upregulate tyrosinase and increase eumelanin production

Melanotan II

Non-selective cyclic melanocortin receptor agonist activating MC1R, MC3R, MC4R, and MC5R; produces simultaneous tanning, sexual arousal, appetite suppression, and fat mobilization

Receptor Targets

Melanotan I

Primarily MC1R (melanocortin 1 receptor) — selective for pigmentation

Melanotan II

MC1R + MC3R + MC4R + MC5R — broad melanocortin activation

Half-Life

Melanotan I

~30 minutes to 2 hours

Melanotan II

~33 minutes

Dosing Frequency

Melanotan I

Typically studied daily during loading, then maintenance

Melanotan II

Typically studied daily during loading, then as needed

Purity

Melanotan I

\u226599% (HPLC verified at 99.8%)

Melanotan II

\u226599% (HPLC verified at 99.7%)

Research Applications

Melanotan I

Photoprotection and UV damage prevention, melanogenesis and tanning mechanisms, erythropoietic protoporphyria (approved in EU as Scenesse), skin cancer prevention, melanocortin receptor selectivity

Melanotan II

Skin pigmentation and tanning, sexual function and arousal (MC4R), appetite suppression and feeding behavior, melanocortin receptor pharmacology, body composition effects

Molecular Weight

Melanotan I

1646.87 Da (13 amino acids, linear)

Melanotan II

1024.18 Da (7 amino acids, cyclic)

Starting Price

Melanotan I

$34.95/vial (10mg)

Melanotan II

$34.95/vial (10mg)

Which Is Right for Your Research?

Choose Melanotan I for selective MC1R photoprotection and melanogenesis research with fewer off-target effects. Choose Melanotan II for broader melanocortin research including sexual function (MC4R) and appetite suppression alongside tanning effects.

Melanotan I
Starting price$34.95
Purity≥99%
CAS75921-69-6
View Melanotan I
Melanotan II
Starting price$34.95
Purity≥99%
CAS121062-08-6
View Melanotan II