A filtering unit for removing a virucidal substance from a biological fluid including an outer casing having at least one input aperture and at least one output aperture. The outer casing including a filter medium, which separates the filtration unit into an input compartment and an output compartment. The filter medium includes at least one hydrophilic material able to absorb or adsorb the virucidal substance. The at least one hydrophilic material includes either porous non-woven material or a porous membrane.
