Biuret is a chemical compound that consists of two urea molecules linked by a peptide bond. It is often used in laboratory settings to test for the presence of proteins. When mixed with a protein solution, biuret reacts to form a colored complex, which can be measured to determine protein concentration. The Biuret test is a simple and effective method for detecting proteins in various samples, such as food or biological fluids. The intensity of the color produced in the reaction is proportional to the amount of protein present, making it a valuable tool in biochemistry and nutrition studies.