Overview Of Cell Separation And Isolation

Researchers can isolate cells from a tissue and separate them to obtain a population containing only a single type of cells.

Other than blood, all tissue samples must first be minced into pieces and incubated with proteolytic enzymes to release individual cells.

These cells can then be further isolated based on their physical and biochemical properties.

Density gradient centrifugation uses an inert medium, such as Ficoll, to create a density gradient and separate cells into layers based on their density upon centrifugation.

Other techniques, such as cell affinity chromatography and fluorescence-activated cell sorting or FACS, use affinity interactions of cell surface molecules to isolate cells.

Cell affinity chromatography uses ligands, such as antibodies, immobilized on a stationary matrix to separate target cells that express a specific receptor while the rest of the cells flow through.

Similarly, FACS uses fluorescence-tagged antibodies to sort cells from a mixture based on their cell-surface antigens. 

The homogeneous cell populations obtained from cell separation methods can be grown in the lab to establish cell cultures or used directly for analysis.