PT-141: research summary
For laboratory research use only. Not for human or veterinary use. This page summarises published literature. It gives no advice on use.
What the literature covers
PT-141 (bremelanotide) is a synthetic cyclic heptapeptide that agonises melanocortin receptors. It is a metabolite-related analogue of Melanotan II: the C-terminal amide is replaced with a free carboxylic acid.
Analytical literature describes how to characterise it. LC-HRMS/MS has been used to profile bremelanotide acetate and its degradation products, including epimerisation, and UHPLC-MS/MS methods quantify it at very low concentrations.
PT-141 has a molecular weight of about 1025.2 g/mol (C50H68N14O10). The cyclic lactam bridge and its D-amino acid make degradant and epimer checks relevant to quality control.
Key facts
| PT-141 | Melanotan II | |
|---|---|---|
| CAS | 189691-06-3 | 121062-08-6 |
| Formula | C50H68N14O10 | C50H69N15O9 |
| Molecular weight (g/mol) | 1025.2 | 1024.2 |
Source: PubChem CID 9941379.
PT-141 compared with Melanotan II
PT-141 and Melanotan II are closely related cyclic melanocortin peptides that differ at the C-terminus: PT-141 ends in a free acid, Melanotan II in an amide. Their masses differ by about 1 Da, so the CoA needs high-resolution mass spectrometry to tell them apart.
Full side-by-side: PT-141 vs Melanotan II
Frequently asked questions
- What is the generic name of PT-141?
- Bremelanotide.
- How does PT-141 differ from Melanotan II?
- PT-141 has a C-terminal carboxylic acid where Melanotan II has an amide. Otherwise the cyclic structures are closely related.
- What analytical methods are published for PT-141?
- LC-HRMS/MS degradant profiling and UHPLC-MS/MS quantification are both in the peer-reviewed literature.
Published literature cited
- Yuvaraaj VK, Sharma N. (2026). Comprehensive characterization of bremelanotide acetate and its degradants by LC-HRMS/MS and predicting epimerization through computational modelling. Anal Methods. PMID 42485063 · doi:10.1039/d6ay01098a
- Sauter M, Uhl P, Burhenne J, Haefeli WE. (2020). Ultra-sensitive quantification of the therapeutic cyclic peptide bremelanotide utilizing UHPLC-MS/MS for evaluation of its oral plasma pharmacokinetics. J Pharm Biomed Anal. PMID 32353679 · doi:10.1016/j.jpba.2020.113276
Every citation was looked up by PMID in Europe PMC (MEDLINE) on 2026-10-14 and its title matched. Citation means the paper exists and is relevant to the compound. It does not mean the paper supports any use.