Osmora Scientific Glossary
Molecular mass
The mass of a molecule, commonly expressed in daltons (Da) or as g/mol, calculated from the masses of its constituent atoms. For a peptide it is derived from its amino-acid composition.
In plain language
How much one molecule weighs. For a peptide, you can calculate it from the sequence.
Why it matters in research
A measured mass compared against the calculated value is central to confirming a peptide's identity by mass spectrometry.
Where you'll encounter it
COA identity fields and mass-spectrometry results.
Related terms
Related Academy lessons
Source
- IUPAC-IUB Joint Commission on Biochemical Nomenclature. "Nomenclature and Symbolism for Amino Acids and Peptides."