ROTORS Rotor is the rotating unit of Centrifuge. Rotor is the movable part of machine which separated the particles present in the sample. For low speed centrifugation, rotor is made up of Brass or Steal (low stress) and for high speed centrifugation, rotor is made up of Aluminium or Titanium (high stress). DIFFERENT TYPES OF ROTORS (i) Vertical tube rotors Vertical tube rotors are first introduced during 1970’s for high speed and ultracentrifuges. The Vertical tube rotor is a fixed zero angle rotor. In this, the tubes are aligned vertically in the body of the rotor at all times. In Vertical tube rotor, the pellet is deposited along the entire length of the outer wall of the centrifuge tube. It is the major disadvantage because the pellet tends to fall back into the solutions at the end of centrifugation. (ii) Fixed angle rotors Fixed-angle rotors are the most ubiquitous rotors used in centrifugation. In Fixed angle rotors, the tubes are placed at a fixed angle between 14° to 4