Fibrinogen is a protein in the blood plasma that is essential for the coagulation of blood and is converted to fibrin by the action of thrombin in the presence of ionised calcium. It is also called “coagulation factor I”.
The Swedish physiologist Olof Hammarsten discovered fibrinogen in 1877 after researching what substances in the blood cause it to coagulate. In his 1877 publication, he notes the method he used to isolate fibrinogen:
- He first separated the plasma from horse blood and mixed it with sodium chloride after which a precipitate was formed.
- This precipitate was then dissolved in a 6-8% solution of sodium chloride causing a precipitate to be formed again. This step was repeated a few times until an insoluble precipitate (fibrinogen) was formed.
Here is a photograph of Olof Hammarsten: