A07 Ultracentrifugation

Purpose

To summarize the operation of an ultracentrifuge.

Procedure

  1. Ultracentrifuges are particularly dangerous. Each laboratory will have a checkout procedure for training personnel in their use. Follow the centrifuge manufacturer's recommendations and procedures. Check a two-pan balance, and adjust for balance. Place the tubes in the tube holders, and place them on the pans of the balance. Add fluid to each tube carefully until the tubes are balanced exactly. (Oil may be placed in the top of the tubes to balance them.) Insert the holder top, and fasten with the fastening device until the numbers on the top and bottom are aligned exactly.
  2. The numbers must be aligned precisely. Install the buckets on the rotor. Inside the centrifuge the buckets will swing out as the rotor turns. Double check that each tube holder is securely attached.
  3. The rotor is installed in the centrifuge. Set the controls according to the centrifuge manufacturer's specifications. Set and allow the device to achieve the vacuum recommended by the manufacturer. Check the pump oil before use. When the run is complete and the rotor has stopped, remove the rotor.
  4. Complete the LOG BOOK. Safety is extremely important in the use of the ultracentrifuge. The only experiment described in this series which calls for ultracentrifugation is the large scale plasmid isolation procedure (B-31).
  5. Other styles of ultracentrifuges than the swinging bucket rotor are available. Run times are often one to two days in duration.

References