For laboratory research use only. Every lot independently tested; certificates published by lot.

MT1 specifications and molecular characteristics

The technical specification for Melanotan I, the MT1 research material supplied by MT1 Peptide Co.: molecular formula C78H111N21O19, average molecular weight 1646.85 g/mol, 13 residues, supplied as a lyophilized powder. Each item is explained below.

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Specification table

Melanotan I specifications
ProductMelanotan I
TypeSynthetic linear α-MSH analog (13 residues)
Molecular formulaC78H111N21O19
Molecular weight1646.85 g/mol (average)
Length13 residues
SequenceAc-Ser-Tyr-Ser-Nle-Glu-His-D-Phe-Arg-Trp-Gly-Lys-Pro-Val-NH2
N-terminusAcetyl (Ac-Ser1)
C-terminusAmide (Val13-NH2)
Non-standard residuesNle4, D-Phe7
Receptor designMelanocortin 1 receptor (MC1R)
FormLyophilized powder
Vial sizes10 mg
Purity specification≥95% (HPLC-UV)
Purity, current lots97.55%
Identity specificationConfirmed by HPLC retention-time match
Testing laboratoryILS Laboratories (independent)
StorageStore sealed, dry and protected from light at the temperature stated on the vial label. Allow a cold vial to reach room temperature before opening.
DesignationResearch use only

Current lot results against specification

Every current lot meets the release specification. Current lots test at 97.55% by HPLC-UV against a specification of ≥95%, and identity is confirmed by HPLC retention-time match on every lot.

HPLC-UV purity by lot. The scale runs from 97.0% to 100% so small differences are visible; every lot shown meets the ≥95% release specification.

All lot records or verify a lot.

MT1 molecular formula

The molecular formula of Melanotan I is C78H111N21O19. Includes the N-terminal acetyl group and C-terminal amide.

MT1 molecular weight

The average molecular weight of Melanotan I is 1646.85 g/mol. "Average" means it is calculated from natural isotope abundances.

MT1 sequence

Ac-Ser-Tyr-Ser-Nle-Glu-His-D-Phe-Arg-Trp-Gly-Lys-Pro-Val-NH2

Structure and modifications

MT1 is linear, with an acetylated N-terminus (Ac-Ser1) and amidated C-terminus (Val13-NH2). Position 4 is norleucine (Nle) and position 7 is D-phenylalanine. The central His-D-Phe-Arg-Trp segment is the core shared by melanocortin receptor ligands. The single tryptophan (Trp9) is its most oxidation-sensitive residue.

Receptor classification

Melanotan I is designed for activity at the melanocortin 1 receptor (MC1R).

Physical form

Lyophilized powder, recorded as the appearance on every certificate. Lyophilization (freeze-drying) removes water, which slows most chemical degradation. What lyophilized means.

Purity and identity specifications

MT1 Peptide Co.’s stated release specification is ≥95% HPLC-UV purity with identity confirmed by HPLC retention-time match against a reference standard. The current lot, KB-34289, reported 97.55%. How purity is measured, or how specifications fit into the quality and supply-chain process.

Analytical and testing methods

HPLC-UV for purity, HPLC-RTM for identity and laboratory quantitation for net content, performed on every lot by ILS Laboratories. Each lot is also screened for fentanyl by immunoassay. LAL endotoxin testing (USP <85>) and PCR microbial screening are reported for lots where they were run. Testing and quality control.

Research designation

Melanotan I is designated research use only: supplied for laboratory research by qualified personnel. Research use only policy.

Buy MT1

10 mg vials. Current lot KB-34289 tested at 97.55% purity with identity confirmed by HPLC retention-time match against a reference standard. Current purchasing is available through Klow.bio.