Modified Glycine Precipitation Technique for the Preparation of Factor VIII Concentrate of High Purity and High Stability

A modification of the glycine precipitation method for the production of factor VIII concentrate is reported. In this procedure, cryoprecipitate was prepared, washed and dissolved in buffer. Contaminating fibrinogen was precipitated by the addition of 2.8 M glycine buffer at 30 degrees C. The fibrinogen precipitate was removed by filtration using a layer of glass beads. Factor VIII was then precipitated from the filtrate by adding solid NaCl. After centrifugation, the precipitate was resuspended in buffer, desalted, sterilized by filtration, lyophilized and subjected to dry-heat treatment. The procedure gave a good recovery of factor VIII (280 IU/l) and seems applicable to large-scale production. The resulting factor VIII concentrate was especially characterized by its high purity (10 IU/mg) and stability both in the liquid state and during dry-heat treatment.