(ŭl″tră-sĕn-trĭf″ū-gā′ shŭn)
[Pronunciation]

Treatment or preparation of substances by use of the ultracentrifuge.
Analytical ultracentrifugation is a means of determining molecular mass, structure, and size. Preparative ultracentrifugation is a means of purifying mixed solutions of proteins. It separates them based on their densities or their sedimentation coeffieients.