Copper oxide isoelectric point

In blood, copper is found in both red cells and plasma. Copper of the red cells is tightly bound to a colorless protein (mol wt approximately 33,000) containing 2 atoms of copper per molecule (erythrocu-prein). Erythrocuprein has an isoelectric point of 5.3 and presents no oxidative properties. Its function in the physiology of the cell is not clear, although there is a rapid exchange between the red cell copper and the plasma copper [47]. 

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