PT 141

PT-141 (bremelanotide) is a synthetic cyclic heptapeptide, Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-OH, that acts on melanocortin receptors, chiefly MC3R and MC4R. It is a metabolite of Melanotan 2 and differs from it only at the C-terminus (a free acid instead of an amide). It is an FDA-approved active ingredient; the material sold here is a research reagent, not a medicine.

Yes, as an active ingredient. The FDA approved bremelanotide (PT-141) in 2019 as the active ingredient of a prescription medicine. The material sold here is a research reagent, not that medicine; it is not manufactured, labeled or approved for any human or veterinary use.

Yes. PT-141 is a synthetic cyclic heptapeptide: seven amino acids, Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-OH, with a lactam bridge between the aspartic acid and lysine side chains forming the ring. It includes two non-standard residues, norleucine and D-phenylalanine, and an acetylated N-terminus. It is the same ring as Melanotan 2, with a free acid in place of that peptide's C-terminal amide.

Research on PT-141 (bremelanotide) has examined melanocortin receptor signaling, chiefly MC3R and MC4R, in cell and rodent models, including central nervous system pathways. It has been investigated in human clinical trials and is an FDA-approved active ingredient; the material sold here is a research reagent, not a medicine. Findings in cells or animals do not establish effects in people.

Nearly, but not quite. PT-141 (bremelanotide) is a metabolite of Melanotan 2 and has the same cyclic seven-residue ring; the only difference is at the C-terminus, a free acid (-OH) on PT-141 versus an amide (-NH2) on Melanotan 2. Both bind several melanocortin receptors. PT-141 is an FDA-approved active ingredient, while Melanotan 2 has never been approved.

They are different peptides acting on different receptor systems. PT-141 is a synthetic cyclic heptapeptide that binds melanocortin receptors, chiefly MC3R and MC4R. Oxytocin is a naturally occurring nonapeptide hormone, cyclized by a disulfide bond, that acts on the oxytocin receptor (OXTR). Both are FDA-approved active ingredients; the materials sold here are research reagents.

Yes, for storage. Keep the sealed lyophilized PT-141 vial refrigerated at 2–8 °C, or frozen at −20 °C for long-term storage, away from light. Once reconstituted, keep the solution refrigerated and avoid repeated freeze-thaw cycles, since its tryptophan residue is prone to oxidation.

PT 141: molecular formula C50H68N14O10; molecular weight 1025.16 g/mol; CAS number 189691-06-3. Sequence: Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-OH. Match these identifiers against the Certificate of Analysis for the lot.

Yes. Each lot has its own Certificate of Analysis, linked on this page for the current lot of each size: 10mg (99.5% HPLC purity). Past certificates are archived in the COA library; contact us with the lot number on the vial label if a certificate is missing.

99.5% (HPLC, current lot). Purity is measured by high-performance liquid chromatography (HPLC) and reported on the lot's Certificate of Analysis.

PT 141 is supplied as lyophilized powder in a sealed vial: 10mg. In stock and dispatched in 1–2 business days. Quantity pricing applies automatically at 5+ and 10+ vials of the same size.

Store sealed at −20 °C, dry and protected from light.