Why does biuret reagent detect proteins better than amino acids?

Answer 1

Biuret reagent does not react with amino acids. It reacts with peptides, polypeptides and proteins because it reacts with the peptide bond (or amide bond) that occurs in these compounds. A peptide bond is formed when two amino acids react with each other: the carboxy group (R-COO-) of one of them reacts with the amino group (R-NH3+) of the other, liberating a molecule of H2O (in the cell this reaction is catalysed by an enzyme and it is necessary activated forms of the reactants). O. K. ?