What Is Hemin?
Hemin, also known as protohemin, is an organic compound forming blue-violet or black-violet crystals or powder. Its IUPAC name is ferriprotoporphyrin Ⅸ chloride, and it has a CAS registration number of 16009-13-5.
Uses of Hemin
Hemin is used as a pharmaceutical intermediate, particularly in treatments related to blood and hemoglobin. In medicine, it induces differentiation in cells of the erythrocyte lineage. As a trivalent iron complex of porphyrin with one chloride ion, hemin plays a vital role in hemoglobin production in blood.
Properties of Hemin
Hemin is somewhat soluble in dimethyl sulfoxide, but extremely insoluble in ethanol and almost insoluble in water. It is sensitive to light, so glass is considered the safest storage container. For preservation, it should be stored away from light, and sealed in a refrigerator at 2~10℃.
Structure of Hemin
Hemin is a trivalent iron complex of porphyrin with a chlorine ion bonded to it. Its molecular structure is pyramidal, with one ligand perpendicular to the square plane of porphyrin. The chemical formula of hemin is C34H32ClFeN4O4, and its molecular weight is 651.94. Porphyrin, the base structure of hemin, consists of four pyrrole rings joined by four carbons with a side chain attached to a closed porphine ring.
Other Information on Hemin
1. Synthesis of Hemin
Hemin can be crystallized by heating blood with glacial acetic acid and salt. It is typically obtained as chlorohemin.
2. Hemin as a Pigment
Hemin is the pigment in enzymes like catalase and peroxidase and is thought to be similar to the pigmented parts of cytochrome and cytochrome oxidase. It tests positive for benzidine staining, is used for hemoglobin detection, and induces erythroid differentiation in certain leukemia cells.
3. Related Compounds of Hemin
Hemin is also known as ferriprotoporphyrin IX chloride. Protoporphyrin IX, a related compound, has a molar mass of 562.658 and a structure with four methyl groups, two vinyl groups, and two propionate groups attached to the porphine ring.