What is the advantages of using biuret reaction in place of measuring the absorption of the protein solution at 280 nm?

Answer 1

The absorption of proteins at 280nm is according to electrons from the rings on the amino acid such as His, Trp, etc. And if there is no such kind of amino acids in the protein, we might not be able to get what the amount of the protein really is. At the other hand, what makes biuret reaction work is by the copper ion reacting with the dipeptide bonds, since every amino acid has the peptide bond, it's more accurate and reasonable to use biuret reactions to determine what the amount of the protein is.

Answer 2

High advantage of using Biuret assay is obtaining high accuracy results. The Biuret assay is rich enough to abstained proteins in concentrations between 0.005 and 2 mg/mL thus it refer as "Pierce assay" after the manufacturer of a reagent kit.

Answer 3

One advantage of using the biuret reaction is that it can measure total protein concentration, not just proteins that absorb at 280 nm like tryptophan and tyrosine containing proteins. Additionally, biuret assay is more sensitive and can detect a wider range of protein concentrations compared to absorbance at 280 nm.