We know that copper sulfate can be used in an experiment to test whether or not a protein is at hand, etc. Hope this helps!
Because is a reactive for identification protein through a reaction called Biuret ;
Copper sulfate is an indicator solution for proteins due to the Biuret test, which detects proteins through a color change when copper ions bind with peptide bonds. In an alkaline solution, the presence of proteins results in a violet color. The intensity of the color relates to the concentration of proteins present in the solution.
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