Fetal Bovine Serum heat inactivated (HI), originated from Brazil, certified for EU. FBS is sterile filtered and quality tested to ensure the highest quality. Fetal bovine serum is a fraction of plasma remaining after coagulation of blood, during which process the plasma protein fibrinogen is converted to fibrin and remains behind in the clot. Fetal bovine serum comes from the blood drawn from a bovine fetus via a closed system of collection.