Ceruloplasmin is a copper-containing enzyme that aids in the body’s iron metabolism. Copper, an essential mineral that is absorbed into the body through diet, is absorbed in the intestines and then transported to the liver, where it is stored or used in the production of a variety of enzymes. The liver then binds copper to apoceruloplasmin to produce Ceruloplasmin and then releases it into the bloodstream. About 95% of the copper in the blood is bound to Ceruloplasmin. Because of this, the Ceruloplasmin test can be used along with one or more copper tests to evaluate copper metabolism and help diagnose Wilson's disease.