Although sterilising blood with heat or radiation gets rid of viruses, it also destroys live cells. But the damage can be avoided if the blood is dried before irradiation, according to a patent application from the company Clearant of Los Angeles (WO 2004/9138).
The blood is rapidly cooled in a vacuum to freeze-dry it, and then placed in an inert atmosphere of argon gas and subjected to low-level gamma radiation for around 24 hours. Thawing and adding water leaves sterilised blood with its red and white cells unharmed.
