An apparatus designed for rapid separation of solids in suspension by rotating them in a container at very high speeds. The organelles of ruptured cells can be separated in this way. An ultracentrifuge rotates at much higher speeds (up to a million times per second) and is used to separate colloidal particles such as large protein molecules. As the sedimentation rate (see sedimentation coefficient) depends on the particle size, the size of particles can be estimated. The ultracentrifuge operates under refrigeration in a vacuum. See also density-gradient centrifugation. |
