Removal of virus through novel membrane filtration method.

To protect against virus infections, the new technology of the virus removal membrane has been developed. The novel virus removal filter PLANOVA is validated for virus removal, that is, reproducible and predictable. The removal is based on the sieving mechanism. The removal of viruses by PLANOVA with a given mean pore size ranging between 10 and 75 nm is predictable when the geometrical size and the deformability of the virus are known in advance under the given filtration conditions. The high removability of viruses originates from the unique pore structure, that is the structure of the multi-layer (or multi-screen) each of which is composed of two types of pores, the capillary and void pores. The good recovery rate of proteins is attained by using material with a good hydroscopic property such as regenerated cellulose. Designing the worst case of the process and selecting model viruses in the process validation experiment are important in the practical application of PLANOVA. The integrity tests by the membrane producer and by the user have been established. Although PLANOVA has already worked well in the field of drug manufacture, the combination of virus removal using PLANOVA and virus inactivation treatment gives potentially wide application.