Ceruloplasmin has the activity of

Whole blood contains about 100 microgram/dl of copper. Out of this, 95% is in RBC as colourless erythrocuprein. In plasma, ceruloplasmin is an impoant copper-containing protein (see Chapter 28). Normal serum level of ceruloplasmin is 25-50 mg/dl. Ceruloplasmin is a blue-colored glycoprotein (Latin "caeruleus" = blue). It is also called serum ferroxidase. It promotes oxidation of ferrous ion to ferric form, which is incorporated into transferrin. The copper atoms are tightly bound with ceruloplasmin. So copper from ceruloplasmin cannot be released easily. About 10% of copper in plasma is loosely bound with albumin, which constitutes the transpo form of copper.Ref: DM Vasudevan, page no: 428