How to Read a PT-141 (Bremelanotide) Certificate of Analysis (COA)
A Certificate of Analysis is only useful if you know which number on it matters for the compound in front of you. For PT-141 (Bremelanotide), the informative checks are not the same as for a generic short peptide.
In plain English
Confirm the weight near 1025.2 and check for a companion peak 16 units above it, indicating light damage. Also confirm the ring actually closed — an unclosed version differs by 18 units, because closing the ring releases a water molecule. That check applies only to ring-shaped molecules.
What PT-141 (Bremelanotide) actually is
PT-141 has an unusual history. It is a breakdown product of a compound originally developed for research into skin pigmentation, and an unexpected observation during that work redirected attention to the breakdown product, which was then developed as its own line of research.
Supplied for laboratory research use only — not for human or animal use.
Third-party tested by HPLC and LC-MS, ≥99% purity, with a Certificate of Analysis on every order. Ships across Canada.
Technical detail below
Assays that are informative for PT-141 (Bremelanotide)
What to check on the COA
Confirm the mass near 1025.2 Da and check for oxidised (+16 Da) species from the tryptophan. Also confirm the cyclic form: a linear (uncyclised) impurity differs by 18 Da from the cyclised product, since ring closure eliminates a water molecule.
Uncyclised linear precursor, oxidised tryptophan species, deletion sequences.
Verify a Popular Peptides batch
Every batch is third-party tested by HPLC and LC-MS with a published Certificate of Analysis (≥99% purity). Enter a lot number to pull the COA for the exact vial in front of you.
What PT-141 (Bremelanotide) is studied for
Acts at melanocortin receptors, with MC3R and MC4R the subtypes of research interest.
Distinguished in the literature by acting centrally, unlike vascular-mechanism compounds in adjacent research areas.
Its origin as a metabolite of a pigmentation-research compound is central to understanding its development history.
The lactam bridge restricts conformational freedom, a common strategy for improving receptor selectivity.
Summarizes published preclinical literature. Provided for research reference only; not a claim of efficacy or a description of human use.
More PT-141 (Bremelanotide) reference
Lyophilized and reconstituted storage conditions, plus the practical working window.
Diluent selection, dissolution behaviour, and the calculator preset for this compound.
Which solvents work, why, and what abnormal dissolution behaviour indicates.
The specific chemical routes by which this molecule breaks down, and how to limit each.
Compound-specific bench practices, and the errors most often made with this molecule.
What to inspect on arrival, and which conditions actually warrant rejecting a vial.
Questions specific to this compound — structure, chemistry, and common misconceptions.
Purity & COA reference for other compounds
PT-141 (Bremelanotide) is supplied strictly as a research chemical for in-vitro laboratory and research use only. It is not intended for human or animal consumption, diagnostic, or therapeutic use. This page is educational laboratory-handling reference information — not medical advice, not usage guidance, and not a protocol.