PT-141, also known as Bremelanotide, is a synthetic cyclic heptapeptide and melanocortin receptor agonist derived from Melanotan II. CAS Number: 189691-06-3. Molecular weight: 1025.2 Da. It is a 7-amino acid peptide that activates MC3R and MC4R receptors and has been studied in preclinical research models.

Preclinical studies on sexual behavior facilitation in rats (PNAS, 2004 PMC454387); melanocortin-4 receptor agonism in sexual brain processing (J Endo Soc, 2022 PMC9625176); erectile function modulation (Eur Urol, 2004 ScienceDirect) All findings referenced are from preclinical and in vitro studies. No approved clinical applications exist for this research compound.

-20°C or below, desiccated, protected from light GenScript Bachem Avoid repeated freeze-thaw cycles. Once reconstituted, the solution should be refrigerated at 2-8°C and used within 28 days.

Peptide.co’s PT-141 has been verified at 99.3% purity through independent third-party HPLC testing. The current batch (Lot #YPB.274, 10mg) includes a full Certificate of Analysis confirming identity, purity, and peptide content. All COAs are publicly available at coa.peptide.co. Testing covers HPLC purity analysis, mass spectrometry identity confirmation, heavy metals screening (<20 ppb), and microbial limits (TAMC/TYMC: 0 CFU). All products are manufactured in FDA-registered facilities in the United States.

Agonist at melanocortin receptors including MC3R and MC4R in the central nervous system (hypothalamus), analogue of alpha-MSH and active metabolite of Melanotan II PubMed 12851303 These mechanisms have been characterized in preclinical models only.

PT-141 is supplied as a lyophilized (freeze-dried) powder and must be reconstituted before use in research applications. The standard reconstitution solvent is bacteriostatic water (sterile water containing 0.9% benzyl alcohol). When reconstituting, direct the solvent gently along the inside wall of the vial — do not spray directly onto the lyophilized powder. Allow the peptide to dissolve naturally without shaking or vortexing. For detailed reconstitution volume calculations, use the free Bacteriostatic Water Calculator or Peptide Reconstitution Calculator on Peptide.co.