Factor VIII fractionation on aminohexyl Sepharose with possible reduction in hepatitis B antigen

The method of factor VIII purification by chromatography on aminohexyl Sepharose has been extended so that up to 100 ml of intermediate purity concentrate can be processed on an 8.6 ml column. The product has a specific activity of 1.8 International Units of factor VIII per mg of protein. Most of the fibrinogen is removed and antibodies to blood group substances A and B are not detectable by haemagglutination techniques. Hepatitis B antigen has been reduced to one sixteenth of that in the starting material, in preliminary experiments. The process has the added advantage that it concentrates the factor VIII relative to the starting material.