Difference Between Iron and Ferritin

Iron vs Ferritin

Among all the chemical elements in the universe, there are some elements which are essential for the efficient functioning of organisms. Iron is one of the necessary elements for all the living beings. It is important to control the level of elements in our bodies. Excess or the lack of these than the normal level could cause diseases. Most of the time, proteins are involved in controlling the level of elements in organisms. Ferritin is one such protein which is related with controlling iron.


Iron is a metal in the d block with the symbol Fe. It is one of the most common elements forming the earth and has large amounts in the inner and outer core of the earth. It is the fourth most common element in the earth’s crust. The pure iron solid has a shiny silvery gray appearance but when exposed to air and water it forms the iron oxide which is commonly known as rust.

The atomic number of iron is 26, and it is a metal in the first transition metal series. The electron configuration of iron is [Ar] 3d6 4s2. Iron has four stable isotopes naturally. They are 54Fe, 56Fe, 57Fe and 58Fe. Among these, the most abundant isotope is 56Fe. Iron has oxidation states ranging from −2 to +8. Among these +2 and the +3 forms are the most common. +2 oxidation form of iron is known as ferrous and +3 form is known as ferric. These ions are in the form of ionic crystals, which are formed with various anions.

Biological systems need iron for various purposes. For example in humans, ferrous is found as a chelating agent in hemoglobin. It is also important for the chlorophyll synthesis in plants. Hence, when there is a deficiency of this ion, biological systems show various diseases. Iron, being a metal, has good thermal and electric conductivity. The purity of the iron sample affects the mechanical strength of it. When the amount of carbon is higher in iron, its hardness and tensile strength is increased.


Ferritin is a protein which is found in cells which is in control of iron. Its function is to store iron and release it when necessary. Iron control is done in a controlled manner inside cells by this protein. By the amount of ferritin in cells, we can predict the amount of iron present. This is a common protein to all the living organisms. Not only higher level animals and plants, but also algae and bacteria produce the ferritin.

Ferritin is a globular protein consisting 24 sub units. Its size is 450 kDa. When ferritin is not combined with iron, it is known as apoferritin. Ferritin stores iron, so that excess of iron won’t be toxic to cells. It also transports iron to places where iron is required and releases. When there is a low level of ferritin, there is a risk for lack of iron, and this could lead to anemia.


What is the difference between Iron and Ferritin?

• Iron is a chemical element, and ferritin is a protein.

• Therefore, ferritin has a higher molar weight that iron.

• Ferritin controls the storage and release of iron inside cells.