Biochemical characterization of autologous fibrinogen adhesive.
Fibrinogen-based adhesive, derived from pooled human plasma, has been used in Europe with great success in otologic surgery, but has not been approved for use in the U.S. because of the risk of transmitting hepatitis. Autologous fibrinogen, derived by polyethylene glycol precipitation from the blood of an individual patient would avoid this risk, and has been shown to be relatively safe to the ear in animal studies. A study of the biochemical composition of this autologous fibrinogen concentrate derived from 15 human volunteer donors was performed. The mean starting plasma fibrinogen was 2.12 mg/ml (range 1.59-3.22 mg/ml). When 10% polyethylene glycol was used to precipitate the fibrinogen, the concentrate contained, on the average, 31.8 mg of fibrinogen/ml. The percent yield averaged 54.9%, and the protein in the final product was 91.9% fibrinogen. Increasing the polyethylene glycol concentration in the precipitation process to as high as 15% resulted in an increased yield as high as 91%, but the protein in the final product was only 42.5% fibrinogen. Polyacrylamide gel electrophoresis confirmed that the predominant protein in the 10% polyethylene glycol precipitate was fibrinogen. These data suggest that highly concentrated fibrinogen can be derived with relative ease from single donor human plasma, and that the product is relatively pure. When combined with thrombin and calcium chloride, this concentrate should provide an adhesive that avoids the risks associated with fibrinogen adhesive derived from pooled blood.