How does biuret assay determine protein concentration?

A more accurate method is to perform a linear regression analysis on the standard curve which will yield the equation for a straight line: y = mx+b. With this equation you can calculate the concentration by entering the absorbance value of each unknown into the equation as the y value and then solve for x.

What is the principle of biuret method?

The biuret test is a chemical assay used to determine the presence of peptide bonds in a molecule. The assay is based on the principle that the copper(II) ion, Cu2+, will form a violet complex with peptide bonds in a solution. The intensity of the violet color is used to determine the presence of peptide bonds.

Why is Biuret test important?

Biuret test is important mainly because it can detect the amount of protein in urine. Excess of protein can lead to kidney disease and other health-related conditions like diabetes mellitus and high blood pressure.

How does the biuret assay work and why is it used?

A Biuret test is a chemical test used to determine the presence of a peptide bond in a substance. It is based on the biuret reaction in which a peptide structure containing at least two peptide links produces a violet color when treated with alkaline copper sulfate.

Which chemical is used in biuret test?

The Biuret reagent is a solution composed of sodium hydroxide (NaOH), hydrated copper (II) sulfate, and potassium sodium tartrate.

What colour is Biuret reagent?

Testing for Proteins We used Biuret’s reagent to detect the presence of proteins in solution. The reagent is pale blue when pure, but when mixed with proteins, the resulting reaction produces a pale purple color.

What does the biuret test detect?

peptide bonds
The biuret test is a chemical test that can be used to check for the presence of peptide bonds in a given analyte. Therefore, the biuret test can be also be used to gauge the amount of protein present in the analyte.

What is the colour change of biuret test?

Proteins are detected using Biuret reagent . This turns a mauve or purple colour when mixed with protein.

What colour is biuret reagent?

Why is NaOH used in biuret test?

The reagent used in the Biuret Test is a solution of copper sulfate (CuSO4) and sodium hydroxide (NaOH). The NaOH is there to raise the pH of the solution to alkaline levels; the crucial component is the copper II ion (Cu2+) from the CuSO4.

What color is positive for protein?

The violet color is a positive test for the presence of protein, and the intensity of the color is proportional to the number of peptide bonds in the solution.