Explain the Biuret Test?
It identifies the presence of peptides and proteins. A minimum of two peptide bonds (tripeptide) are required for a positive test. A tripeptide will give a pale violet color when treated with an alkaline solution of dilute copper (blue). Used for both qualitative and quantitative estimation of proteins. Amino acids and dipeptides will NOT give a positive biuret test.
What can the Biuret Test be used for?
Since amino acids do not give positive tests, this can be used to distinguish proteins from amino acids.