This test card is used for quantitative determination of ferritin in human serum, plasma or whole blood in vitro. Ferritin is a macromolecular protein with a molecular weight of at least 440kd (depending on the amount of iron in it). Serum ferritin is the binding iron in blood. It is the most sensitive index to detect iron deficiency in the body. The determination of ferritin is a suitable method to determine the iron metabolism. The determination of ferritin content in the early stage of treatment is a typical method to estimate the iron content in vivo. The determination of serum ferritin is often used in the diagnosis of iron deficiency anemia. The low level of ferritin accompanied by small cell hypopigmentation anemia suggests iron deficiency. If the level of ferritin increases and the possibility of iron distribution disorder can be excluded at the same time, it means that the iron content in the body is too high.