Ultracentrifugation in the WX Ultra Series can support only 30 mL samples at a time, and therefore do not significantly concentrate viruses. Tangential flow filtration enables viral concentration of large volumes that can then be purified using sucrose density gradients. Contact Dr. Steven Wilhelm (wilhelm@utk.edu) or Samantha Coy (srose16@vols.utk.edu) for additional information regarding this protocol.