PT-141 (10MG)

PT-141 (bremelanotide) — a cyclic 7-residue melanocortin-receptor-agonist research peptide — supplied by BioFusion as a vacuum-sealed lyophilized 10mg vial for MC4R-selective research chemistry.

Research context

PT-141 (bremelanotide) is the canonical MC4R-selective reference standard, structurally a metabolite of Melanotan II with a free C-terminal hydroxyl in place of the C-terminal amide. The structural difference produces a meaningful shift in receptor-subtype selectivity that makes PT-141 the preferred reference in MC4R-focused research panels. Studied alongside Melanotan II in cross-subtype selectivity-mapping work.

Synthesis & documentation

Produced by solid-phase peptide synthesis using Fmoc protecting-group strategy in a U.S.-based ISO 9001:2008 facility, with the on-resin lactam-bridge cyclization step verified by LC-MS post-cleavage. Each lot is verified for identity (LC-MS), purity (reverse-phase HPLC-UV ≥99.0%), moisture (Karl Fischer), and counter-ion (ion chromatography). Signed COA ships with every order; lot history on the COA library.

Storage & handling

Lyophilized PT-141 is stable at −20 °C for the printed shelf life. After reconstitution, the standard 14-day-at-2-8 °C reference window applies; avoid freeze-thaw cycling. The cyclic structure is robust under typical research-handling conditions. The reconstitution calculator handles working-concentration math for 10mg-vial protocols.

Why BioFusion

The PT-141 vs Melanotan II distinction matters at the chemistry level — many third-party listings conflate them or supply the wrong terminus. BioFusion verifies the C-terminal acid form by LC-MS (mass = MT-II + 1 Da, +OH vs −NH₂) and HPLC-purity ≥99.0% on every release. Batch transparency ledger publishes per-lot data. Bulk discounts at three+; members save 25%.

For research and laboratory use only. This product is not a drug, food, or cosmetic, and is not intended for diagnostic, therapeutic, or in vivo human use.