How does a Laboratory Centrifuge Work?

There are many types of centrifugation: Isopycnic centrifugation, often used to isolate nucleic acids like DNA. Differential centrifugation, often used to separate some types of organelles from whole cells for further analysis of certain parts of the cells. Sucrose gradient centrifugation, this type of centrifugation is often used to purify certain enveloped viruses and ribosomes, and also to separate cell organelles from the crude cellular extracts.


Laboratory centrifuges are most commonly used in biology, chemistry and biochemistry for isolating and separating solids from liquids in a suspension. The solids can be biomolecules, insoluble compounds, cell organelles or whole cells. They will vary widely in capacity and speed. Normally they will comprise a rotor containing 2,6 or more numbered wells within which centrifuge tubes can be placed. When you centrifuge a suspension in a centrifuge tube, the soils will settle at the bottom of the centrifuge tube.


The rotor will be covered by a plastic cover, this cover is usually interlocked in order to prevent the motor from turning the rotor when its open, and also from allowing the cover to be opened before the rotor stops for a few minutes. The cover is there to protect the user from any injury caused by touching a rapidly spinning rotor. It also offers protection to the person using the unit from fragments in case the rotor fails. The rotor needs to be balanced by placing blanks or samples of equal mass opposite each other. Since almost all of the mass is derived from the solvent, it is normally sufficient to place samples or blanks of equal volume. As an added safety feature, some centrifuges can stop turning when any wobbling is detected.


Jenkins Electric Motors have been in existence for over 60 years, and we have gained a great wealth of experience and knowledge in a wide range of industries. Whether you are developing a new product or you need a replacement motor, we can assist. For more information on what we have to offer at Jenkins Electric Motors, visit our website on or give us a call on 011 450 0575.

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