PT-141 is a synthetic melanocortin peptide, and this page is written for laboratories in the United Kingdom and Ireland that are deciding where to buy PT-141. Below are the three formats we list with the price of each, the chemistry of the molecule, its neighbours in our catalogue, how a lyophilised vial is handled and what a parcel to a British or Irish address involves. Everything here is written for laboratory and research work. PT-141 is with us neither a medicine nor a supplement, and we make no statement about what anyone would observe.
Price and packaging
Prices are in euros. The per-milligram column is worked out from the price and the pack size, and stays empty where a pack is not sold by weight.
| Format | Pack | Price | Price per mg |
|---|---|---|---|
| PT-141 vial | 10 mg lyophilised powder | € 54,95 | € 5,50 |
| PT-141 pen | 10 mg in a pen | € 94,95 | € 9,50 |
| PT-141 nasal spray kit | kit | € 64,95 | not applicable |
The vial and the pen hold the same ten milligrams, so the gap between € 5,50 and € 9,50 per milligram is the pen hardware rather than more material. A more convenient pack is not automatically the keener one per milligram, and here it is not.
What PT-141 is
PT-141 is the development code for bremelanotide. It is a synthetic cyclic heptapeptide belonging to the melanocortin family, the group of peptides related to alpha-MSH. The molecular formula is C50H68N14O10 and the molecular mass is close to 1025 g/mol.
The molecule is built as a ring. The sequence is written Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-OH: an acetylated norleucine at the front, then a lactam bridge between the aspartate and lysine side chains that closes six residues into a cycle. The D-phenylalanine inside the ring is the mirror image of the ordinary amino acid, and ring plus inversion make the peptide harder for peptidases to take apart.
What separates PT-141 from its closest neighbour is a single atom group at the tail. Melanotan II carries a C-terminal amide; bremelanotide carries a free carboxylic acid in the same position and is in fact the deamidated form of it. In the literature both are classified as melanocortin receptor agonists, which we note as chemistry and not as a statement about either compound.
Where it sits in the catalogue
The melanocortin peptides we carry are grouped on our buy Melanotan page. Melanotan II is the cyclic heptapeptide amide described above. Melanotan I, or afamelanotide, is something else again: a linear chain of thirteen residues following alpha-MSH, with norleucine at position four and D-phenylalanine at position seven, and no ring at all. The three sit on a short ladder, from linear thirteen-mer to cyclic seven-mer amide to the same cycle as a free acid.
The other peptides shelved under hormonal research, among them kisspeptin, gonadorelin and oxytocin, come from separate families, so that heading is a shelving decision rather than a chemical one. The full catalogue is set out on buy peptides.
Form, handling and storage
The vial holds a lyophilised cake. Reconstitution is done with bacteriostatic water, added slowly down the inside wall of the vial rather than squirted onto the cake, since a direct jet foams the peptide. Swirl the vial gently until the cake has dissolved and the liquid runs clear. Shaking is neither needed nor wise.
Sealed lyophilised powder is kept cool, dry and out of the light, and refrigeration suits a longer wait. Reconstituted material goes in the fridge and not the freezer, since repeated freezing and thawing is hard on a peptide in solution. Keep the vial upright and label it with the date it was made up.
The nasal spray kit is supplied as a lyophilised vial together with an empty nasal spray bottle and sterile saline for making the solution up. The pen arrives filled and is kept refrigerated from the moment it is received.
Shipping and analysis
Everything ships from the Netherlands. The United Kingdom rate is a flat € 15,95 and the Irish rate a flat € 14,95, both free from € 200. Prices are in euros.
The United Kingdom is not in the European Union, so a parcel arriving there is an import. Any import VAT or duty is charged by the carrier to the recipient, separate from what is paid at the checkout. Ireland is in the European Union, so an Irish parcel does not attract those charges.
Every batch is analysed and a certificate of analysis is available for it, published under laboratory reports. The measured value for a batch is what the certificate states.
Frequently asked questions
What may I use this for?
Laboratory and research purposes only. It is not for human or veterinary use, and we give no dosing advice of any kind.
Are PT-141 and bremelanotide the same thing?
Yes. PT-141 is the development code and bremelanotide is the assigned name for the same cyclic heptapeptide.
Why is the pen dearer per milligram than the vial?
Both hold ten milligrams. The pen costs € 94,95 against € 54,95 for the vial, so € 9,50 per milligram against € 5,50, and the difference is the device rather than extra peptide.
What is in the nasal spray kit?
A lyophilised vial, an empty nasal spray bottle and sterile saline to make the solution up. It is priced as a kit at € 64,95 rather than by weight.
Do you send orders to the United Kingdom and Ireland?
Yes, from the Netherlands, at € 15,95 to the United Kingdom and € 14,95 to Ireland, free from € 200 in both cases. A British parcel is an import, so any import VAT or duty is billed by the carrier to the recipient.
For laboratory and research use only. Not for human or veterinary use.
