Fig. 2

Partial purification of virions by differential centrifugation. A crude preparation of virus containing host debris is subjected to low-speed/short-time centrifugation (e.g. 10,000 g/20 min) followed by high-speed/long-time centrifugation (e.g. 100,000 g/2 h. This cycle can be repeated to obtain a higher degree of purity. The final pellet containing partly purified virus is re-suspended in a small volume of fluid (Carter and Saunders 2007)