Sable · Question
What is the difference between PT-141 and SS-31?
PT-141 is a cyclic heptapeptide melanocortin receptor agonist, a metabolite-like analogue of Melanotan II with a C-terminal acid, used in melanocortin receptor research (cyclic peptide, MW about 1025.2 g/mol).
Research use only. Not for human consumption. No health claims.
Last verified 2026-10-10
What is the difference between PT-141 and SS-31?
PT-141 is a cyclic heptapeptide melanocortin receptor agonist, a metabolite-like analogue of Melanotan II with a C-terminal acid, used in melanocortin receptor research (cyclic peptide, MW about 1025.2 g/mol).
Which is heavier, PT-141 or SS-31?
PT-141 has a molecular weight of about 1025.2 g/mol and SS-31 about 639.8 g/mol (PubChem), so PT-141 is heavier by 385.4 g/mol, a ratio of 1.6. This means 1 mg of PT-141 contains 975.4 nmol versus 1,563 nmol for SS-31.
How many mg of SS-31 are equimolar to 1 mg of PT-141?
1 mg of PT-141 (MW 1025.2) is 975.4 nmol. The same number of moles of SS-31 (MW 639.8) weighs 0.6241 mg. Equimolar comparisons matter when testing two compounds side by side in the same assay.
Compare the molecular formulas of PT-141 and SS-31
PubChem lists PT-141 as C50H68N14O10 (1025.2 g/mol) and SS-31 as C32H49N9O5 (639.8 g/mol). PT-141 is a cyclic peptide; SS-31 is a peptide. These formulas refer to the parent compounds without salt counter-ions.
A 10 mg vial of PT-141 equals how many mg of SS-31 in moles?
10 mg of PT-141 (MW 1025.2) is 9.754 µmol. The same amount of SS-31 (MW 639.8) would weigh 6.241 mg. This equimolar conversion lets two compounds be compared at matched molar amounts in the same experiment.
A 5 mg vial of PT-141 equals how many mg of SS-31 in moles?
5 mg of PT-141 (MW 1025.2) is 4.877 µmol. The same amount of SS-31 (MW 639.8) would weigh 3.12 mg. This equimolar conversion lets two compounds be compared at matched molar amounts in the same experiment.
A 5 mg vial of SS-31 equals how many mg of PT-141 in moles?
5 mg of SS-31 (MW 639.8) is 7.815 µmol. The same amount of PT-141 (MW 1025.2) would weigh 8.012 mg. This equimolar conversion lets two compounds be compared at matched molar amounts in the same experiment.
A 10 mg vial of SS-31 equals how many mg of PT-141 in moles?
10 mg of SS-31 (MW 639.8) is 15.63 µmol. The same amount of PT-141 (MW 1025.2) would weigh 16.024 mg. This equimolar conversion lets two compounds be compared at matched molar amounts in the same experiment.
A CoA for every lot; each vial carries a printed lot number that matches it. Ask with the lot number and we send it.
Cite this
Research use only. Not for consumption. No health claims.
Plain
Sable Peptides. (2026). What is the difference between PT-141 and SS-31?. UK Research Peptide Reference. Retrieved 11 October 2026, from https://www.sablepeptides.co.uk/questions/compare/pt-141-vs-ss-31/#sqa-040440
APA
Sable Peptides. (2026, October 11). *What is the difference between PT-141 and SS-31?*. UK Research Peptide Reference. https://www.sablepeptides.co.uk/questions/compare/pt-141-vs-ss-31/#sqa-040440
BibTeX
@misc{sable_#sqa-040440_2026,
author = {{Sable Peptides}},
title = {{What is the difference between PT-141 and SS-31?}},
year = {2026},
howpublished = {\url{https://www.sablepeptides.co.uk/questions/compare/pt-141-vs-ss-31/#sqa-040440}},
note = {Accessed 11 October 2026. CC BY 4.0}
}Badge
<a href="https://www.sablepeptides.co.uk/ref"><img src="https://www.sablepeptides.co.uk/badge/ref.svg" alt="Data: UK Research Peptide Reference — Sable Peptides" width="220" height="40"></a>
Date modified: 2026-10-10