The process of separating molecules that are of different densities by spinning them around an axis at very high levels is called centrifugation. The centrifugation technique is used widely in diagnostic facilities, medical clinics, and molecular biology laboratories.

Centrifugation is also used in the medical field to harvest DNA, gather cells, purify virus particles, and separate the differences between conforming particles. It is also used in the separation of different blood components.

Blood fractionation is the process of fractionating whole blood. The process involves separating blood into its components. Blood fractionation uses a machine called a blood centrifuge to carry out the procedure.

A certain amount of blood is placed in the blood centrifuge and the machine will spin for several minutes to collect the following components:

  • Blood plasma. This is the clear solution you can see in the upper phase (It can be further separated into other fractions).
  • Thin layer of leukocytes. This is the buffy coat that consists of platelets and white blood cells. This can be found in the middle phase.
  • Erythrocytes. The red blood cells you can find at the bottom of the centrifuge tube.

Blood samples for centrifugation are stored in a serum separation tube. The serum separation tube comes with a silicone gel. After the centrifugation process, the gel will form a layer above the buffy coat.

This will allow the serum to be easily removed for testing and other purposes. The blood centrifuge will typically run the specimen at 1300 – 1800 x g for 10 to 15 minutes. Centrifuge RPMs will vary depending on the centrifuge build and rotor used.

The centrifugation process is considered successful when the gel is intact and the serum and the cells are separated completely in the tube. However, it is not recommended to redo the centrifugation process if the gel barrier is incomplete. In this scenario, the quality of the blood components may be affected rendering it unusable for their intended purpose.

By AESir