Description_x000D_ Application_x000D_ All cells require iron for the proper uptake of oxygen from their environment. Transferrin, a protein isolated from serum, causes the uptake and transport of iron from culture medium to the cells. This allows proper oxygen uptake and also stimulates growth-related enzyme activity. Iron-saturated transferrin (holo transferrin) is continually recycled after releasing iron and becomes iron-deficient transferrin (apo-transferrin). Choosing which form to use depends upon the culture conditions. In media such as Dulbecco′s Modified Eagle′s Medium/Ham′s Nutrient Mixture F12 (DMEM/F12) that contain high levels of iron salt, using apo-transferrin is preferred._x000D_ Packaging_x000D_ 5, 10 g in poly bottle_x000D_ 50, 100, 500 mg in poly bottle