What is the Difference Between Ferritin and Hemosiderin?

Ferritin and hemosiderin are both iron-containing proteins, but they have distinct differences:

1. Solubility: Ferritin is water-soluble and heat-resistant up to 75°C, while hemosiderin is water-insoluble and thermally denatured.
2. Location: Ferritin is found both in cells and in plasma, while hemosiderin is only found within cells.
3. Structure: Ferritin is an intracellular protein that stores iron and releases it in a controlled manner. Hemosiderin, on the other hand, is an iron storage complex composed of partially digested ferritin and other materials.
4. Iron Turnover: The iron turnover of ferritin is active, but that of hemosiderin is passive, mediated by ferritin.
5. Magnetic Susceptibility: Both ferritin and hemosiderin are superparamagnetic, but hemosiderin's magnetic susceptibility effects are more powerful due to its larger particle size.

In summary, ferritin is a water-soluble, heat-resistant protein that actively stores and releases iron, while hemosiderin is an insoluble, thermally denatured complex that passively stores iron and is composed of partially digested ferritin and other materials.

Comparative Table: Ferritin vs Hemosiderin

Ferritin and hemosiderin are two forms of iron storage in the human body. Here is a table comparing their differences:

Both ferritin and hemosiderin play important roles in iron homeostasis and are predominantly found in liver cells. However, ferritin is more readily available for the body's needs, while hemosiderin serves as a secondary storage form when ferritin storage capacity is reached.