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How does centrifugation separate plasma or serum from blood cells?

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blood analysis The physical and chemical properties of a sample of blood are examined during blood analysis. The examination of blood is important for the accurate diagnosis of disease.

Centrifugation separates plasma or serum from blood cells by utilizing centrifugal force to substitute for and amplify the effects of gravity.1

In a centrifuge, blood is placed in a spinning vessel. Because blood cells (such as erythrocytes) are denser than the surrounding fluid, the centrifugal field causes these particles to migrate toward the periphery of the spinning container. As the process continues, the denser cellular components collect against the outer wall as sediment, allowing the lighter, clear plasma to be separated.21

When preparing serum, the blood is typically allowed to clot first, which converts the protein fibrinogen into fibrin. Centrifugation is then used to pack the clotted cells and fibrin at the bottom, leaving the cell-free serum as the supernatant. This separation is highly effective because the rate of migration depends on the intensity of the centrifugal field and the density difference between the suspended particles and the liquid medium.341