The soluble protein content of the sample is often used to calculate the enzyme activity. In addition,
soluble protein content is also used for quality analysis of food.
In strong alkaline solution, biuret forms purple complex with CuSO4, the color of purple complex is
directly proportional to protein concentration, but not related to protein molecular weight and amino acid
composition, so it can be used to determine protein content. This method can be applied to the samples
with high protein concentration, especially animal materials.
Reagents and Equipment Required but Not Provided.
Centrifuge, spectrophotometer, transferpettor, 1 mL glass cuvette and distilled water.
