For Research Use Only — Not for Human or Veterinary Use
MT-1 Refill 10mg is supplied exclusively for in vitro and pre-clinical in vivo research use with the AbsoluteBioLab Reusable Metal Peptide Pen v3. This product has not been evaluated by the MHRA, FDA, or any other regulatory authority for safety or efficacy in humans or animals. Purchase confirms the buyer is a qualified researcher.
MT-1 Refill 10mg — Melanotan I (Afamelanotide) Selective MC1R Agonist Refill Cartridge for the AbsoluteBioLab Peptide Pen v3
The MT-1 Refill 10mg is a pre-filled lyophilised refill cartridge containing research-grade Melanotan I (MT-1), also known as Afamelanotide, a synthetic linear analogue of alpha-melanocyte stimulating hormone (α-MSH) with the sequence [Nle4, D-Phe7]-α-MSH — a 13-amino-acid peptide incorporating a norleucine substitution at position 4 and a D-phenylalanine substitution at position 7 that confer enhanced receptor binding affinity and resistance to proteolytic degradation compared to native α-MSH. MT-1 is a selective agonist at the melanocortin-1 receptor (MC1R), the primary receptor mediating melanogenesis in melanocytes. This refill format is designed for direct use with the AbsoluteBioLab Reusable Metal Peptide Pen v3.
Each refill cartridge contains 10mg of lyophilised MT-1 acetate salt, verified by RP-HPLC to a minimum purity of ≥99.0%, with molecular identity confirmed by ESI-MS. Endotoxin content is certified at <1.0 EU/mg by kinetic turbidimetric LAL assay. A batch-specific Certificate of Analysis is included with every order.
MT-1 was developed at the University of Arizona as part of a systematic effort to create stable, potent melanocortin receptor agonists for research into melanogenesis, photoprotection, and melanocortin receptor pharmacology. The [Nle4, D-Phe7] substitutions in MT-1 increase its binding affinity at MC1R approximately 1,000-fold compared to native α-MSH, while the D-phenylalanine substitution at position 7 provides resistance to aminopeptidase-mediated degradation. MT-1’s selectivity for MC1R over other melanocortin receptor subtypes (MC2R–MC5R) makes it a preferred research tool for studies of MC1R-specific signalling, melanogenesis, and photoprotection.
Compound Identity & Molecular Data
| Parameter | Value |
|---|---|
| Compound Name | Melanotan I (MT-1, Afamelanotide) |
| Sequence | [Nle4, D-Phe7]-α-MSH (13 amino acids) |
| Molecular Weight | 1,646.87 Da (free base, monoisotopic) |
| CAS Number | 75921-69-6 |
| Salt Form | Acetate salt (lyophilised) |
| Receptor Selectivity | MC1R selective (>1,000-fold affinity vs native α-MSH at MC1R) |
| Key Signalling | cAMP/PKA/MITF/TYR melanogenesis pathway; anti-apoptotic signalling |
| Research Classification | Selective MC1R agonist; melanogenesis; photoprotection; pigmentation research |
Analytical Release Testing — Refill Cartridge Specification
| Test | Method | Specification | Notes |
|---|---|---|---|
| Purity | RP-HPLC (C18, UV 220 nm) | ≥99.0% | Acetonitrile/water gradient; TFA modifier |
| Identity | ESI-MS | Confirmed ±0.1 Da | Electrospray ionisation mass spectrometry |
| Endotoxin | Kinetic turbidimetric LAL | <1.0 EU/mg | USP <85> compliant method |
| Residual Moisture | Karl Fischer titration | <5.0% | Coulometric KF; lyophilisation quality indicator |
| Quantity per Cartridge | Gravimetric | Per label ± 5% | Lyophilised acetate salt; net peptide content |
| Compatible Device | — | AbsoluteBioLab Peptide Pen v3 | Use with 4mm 31G pen needles |
Mechanism of Action
MT-1 activates MC1R on melanocytes through its [Nle4, D-Phe7]-α-MSH sequence, stimulating Gs protein-coupled adenylyl cyclase and increasing intracellular cAMP. cAMP activates PKA, which phosphorylates CREB (cAMP response element-binding protein), driving transcription of MITF (microphthalmia-associated transcription factor) — the master regulator of melanocyte differentiation and melanogenesis. MITF upregulates the expression of melanogenic enzymes including tyrosinase (TYR), TRP-1 (tyrosinase-related protein 1), and TRP-2 (DCT), which catalyse the sequential conversion of tyrosine to DOPA, dopaquinone, and ultimately eumelanin (brown/black) or phaeomelanin (yellow/red) depending on the availability of cysteine.
MT-1’s selective activation of MC1R — without significant activity at MC2R (ACTH receptor), MC3R, MC4R, or MC5R — makes it a clean research tool for studying MC1R-specific signalling and melanogenesis without the confounding effects of multi-receptor activation that complicate the use of non-selective melanocortin agonists. MC1R activation by MT-1 also promotes eumelanin synthesis preferentially over phaeomelanin synthesis, through a mechanism involving suppression of the Agouti signalling protein (ASIP) competitive antagonism at MC1R and upregulation of the eumelanin-promoting MITF/TYR pathway.
In addition to its melanogenic effects, MT-1 activates anti-apoptotic signalling in melanocytes through MC1R-mediated PI3K/Akt activation, promoting melanocyte survival in response to UV radiation-induced DNA damage. This anti-apoptotic activity, combined with the photoprotective effect of increased eumelanin production, makes MT-1 a valuable research tool for investigating the mechanisms of UV-induced melanocyte damage and photoprotection in pre-clinical models of photodamage and melanoma.
Research Applications & Reconstitution
MT-1 Refill 10mg is used in pre-clinical pigmentation and photoprotection research. Key applications include studies of MC1R-mediated melanogenesis and the cAMP/PKA/MITF/TYR pathway in melanocyte cell culture models; investigations of eumelanin vs phaeomelanin switching in response to MC1R activation; studies of photoprotection and UV-induced DNA damage in rodent skin models; and investigations of MC1R pharmacology and receptor selectivity in melanocortin receptor binding and functional assays. The refill cartridge format is suited to research programmes requiring repeated subcutaneous administration in pre-clinical photoprotection studies.
This refill cartridge is supplied in lyophilised form and must be reconstituted before use. For use with the AbsoluteBioLab Peptide Pen v3, reconstitute with bacteriostatic water to the desired concentration. A typical reconstitution is 2ml bacteriostatic water per 10mg cartridge to yield a 5mg/ml solution. Allow the lyophilised cake to dissolve completely by gentle swirling — do not vortex. The reconstituted solution should be clear and colourless; discard if particulate matter or discolouration is observed. For in vitro applications, reconstitute in sterile PBS (pH 7.4) or cell culture-grade water.
Storage & Stability
| Condition | Temperature | Duration | Notes |
|---|---|---|---|
| Lyophilised cartridge (long-term) | −20°C | ≥24 months | Desiccated; protect from light and moisture |
| Lyophilised cartridge (short-term) | 2–8°C | Up to 4 weeks | Desiccated; suitable for active research use |
| Reconstituted in bacteriostatic water | 2–8°C | Up to 28 days | Benzyl alcohol preservative extends stability |
| Reconstituted aliquots (extended) | −80°C | Up to 12 months | Single-use aliquots; avoid repeated freeze-thaw cycles |
Reviews
There are no reviews yet.