Sable · Question
What is the difference between GHRP-2 and P21?
GHRP-2 is a synthetic growth hormone secretagogue hexapeptide studied as a ghrelin receptor (GHS-R1a) agonist in endocrine research (peptide, MW about 818 g/mol).
Research use only. Not for human consumption. No health claims.
Last verified 2026-10-10
What is the difference between GHRP-2 and P21?
GHRP-2 is a synthetic growth hormone secretagogue hexapeptide studied as a ghrelin receptor (GHS-R1a) agonist in endocrine research (peptide, MW about 818 g/mol).
Which is heavier, GHRP-2 or P21?
GHRP-2 has a molecular weight of about 818 g/mol and P21 about 578.7 g/mol (PubChem), so GHRP-2 is heavier by 239.3 g/mol, a ratio of 1.41. This means 1 mg of GHRP-2 contains 1,222.5 nmol versus 1,728 nmol for P21.
How many mg of P21 are equimolar to 1 mg of GHRP-2?
1 mg of GHRP-2 (MW 818) is 1,222.5 nmol. The same number of moles of P21 (MW 578.7) weighs 0.7075 mg. Equimolar comparisons matter when testing two compounds side by side in the same assay.
Compare the molecular formulas of GHRP-2 and P21
PubChem lists GHRP-2 as C45H55N9O6 (818 g/mol) and P21 as C27H42N6O8 (578.7 g/mol). GHRP-2 is a peptide; P21 is a peptidomimetic. These formulas refer to the parent compounds without salt counter-ions.
A 5 mg vial of GHRP-2 equals how many mg of P21 in moles?
5 mg of GHRP-2 (MW 818) is 6.112 µmol. The same amount of P21 (MW 578.7) would weigh 3.537 mg. This equimolar conversion lets two compounds be compared at matched molar amounts in the same experiment.
A 10 mg vial of GHRP-2 equals how many mg of P21 in moles?
10 mg of GHRP-2 (MW 818) is 12.225 µmol. The same amount of P21 (MW 578.7) would weigh 7.075 mg. This equimolar conversion lets two compounds be compared at matched molar amounts in the same experiment.
A 10 mg vial of P21 equals how many mg of GHRP-2 in moles?
10 mg of P21 (MW 578.7) is 17.28 µmol. The same amount of GHRP-2 (MW 818) would weigh 14.135 mg. This equimolar conversion lets two compounds be compared at matched molar amounts in the same experiment.
A 5 mg vial of P21 equals how many mg of GHRP-2 in moles?
5 mg of P21 (MW 578.7) is 8.64 µmol. The same amount of GHRP-2 (MW 818) would weigh 7.068 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 GHRP-2 and P21?. UK Research Peptide Reference. Retrieved 11 October 2026, from https://www.sablepeptides.co.uk/questions/compare/ghrp-2-vs-p21/#sqa-039113
APA
Sable Peptides. (2026, October 11). *What is the difference between GHRP-2 and P21?*. UK Research Peptide Reference. https://www.sablepeptides.co.uk/questions/compare/ghrp-2-vs-p21/#sqa-039113
BibTeX
@misc{sable_#sqa-039113_2026,
author = {{Sable Peptides}},
title = {{What is the difference between GHRP-2 and P21?}},
year = {2026},
howpublished = {\url{https://www.sablepeptides.co.uk/questions/compare/ghrp-2-vs-p21/#sqa-039113}},
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