HSA is the most common protein in serum. It is produced in the liver and the concentration in serum is 35-50 mg/ml. HSA consists of a single polypeptide chain of 584 aminoacids, stabilized by 17 disulfide bridges. HSA is often used as a carrier molecule because of its binding capacity, and thus mainly functions as the regulator of the colloidal osmotic pressure of the blood. HSA binds a wide variety of hydrophobic ligands including fatty acids, bilirubin, thyroxine and hemin.