◂ PEPTIDE GLOSSARY
Biochemistry

Molar Mass

Also known as: molecular weight · MW · Dalton · kDa

The mass of one mole of a compound (in g/mol or Daltons) — used to convert between milligrams and moles.

Molar mass (molecular weight) is the mass of one mole of a substance, expressed in grams per mole (g/mol) or, for peptides, in Daltons (Da) or kilodaltons (kDa). It is the sum of the masses of all atoms in the molecule.

It is the number mass spectrometry measures to confirm identity, and it lets researchers convert between a mass (milligrams in a vial) and an amount of substance (moles), which matters when comparing concentrations across compounds of different size.

A peptide’s molar mass follows directly from its amino-acid sequence.

Educational content, not medical advice. All products supplied for research purposes only — not for human consumption.