Rotor-stator homogenizers - What is it? 

Rotor-stator homogenizers - What is it? 

Rotor-stator homogenizers (also called colloid mills or Willems homogenizers) generally outperform cutting blade-type blenders and are well suited for plant and animal tissue. Combined with glass beads, the rotor-stator homogenizer has been successfully used to disrupt microorganisms. However, the homogenized sample is contaminated with minute glass and stainless steel particles and the abrasive wear to the rotor-stator homogenizer is unacceptably high. Cell disruption with the rotor-stator homogenizer involves hydraulic and mechanical shear as well as cavitation. Some people in the homogenizing field also claim that there is to a lesser extent high-energy sonic and ultrasonic pressure gradients involved.

Rotor-stator homogenizers - How does it work? 

The rotor-stator homogenizer or generator type homogenizer was first developed to make dispersions and emulsions, and most biological tissues are quickly and thoroughly homogenized with this apparatus. The appropriately sized cellular material is drawn up into the apparatus by a rapidly rotating rotor (blade) positioned within a static head or tube (stator) containing slots or holes. There the material is centrifugally thrown outward in a pump like fashion to exit through the slots or holes. Because the rotor (blade) turns at a very high rpm, the tissue is rapidly reduced in size by a combination of extreme turbulence, cavitation and scissor-like mechanical shearing occurring within the narrow gap between the rotor and the stator. Since most rotor-stator homogenizers have an open configuration, the product is repeatedly recirculated. The process is fast and depending on the toughness of the tissue sample, desired results will usually be obtained in 15-120 seconds. For the recovery of intracellular organelles or receptor site complexes, shorter times are used and the rotor speed is reduced.