FACS Core Facility

Fluorescence Activated Cell Sorting (FACS) enables a qualitative and quantitative analysis of cell mixtures, as well as the sorting of individual particles using a flow cytometer. The application of this methodology is available to all research groups at the FACS Facility at the Biozentrum.

Detection of 6 subpopulations in a mixture of various Salmonella strains.

Fluorescence Activated Cell Sorting (FACS) is a technology with which mixtures of cells can be analyzed, counted and separated with a special instrument, the flow cytometer. This procedure is already being routinely applied in medical diagnostics in hematology and immunology, in order to identify specific cell types in samples. Furthermore, in various research fields such as cell biology, neurobiology and infection biology FACS is being used more and more frequently and offers completely new possibilities for the analysis and purification of cells and cell organelles.

The procedure
The analysis can be carried out on suspended cells with a size ranging between 0.2 und 100 micrometers, which are first stained with different fluorescent markers such as fluorescent proteins like GFP and RFP, fluorescently labeled antibodies and/or many other stains. In the flow cytometer, these particles/cells pass a laser at up to 130km/h. The scattered light reveals the size and internal structure of the cell, while the fluorescence indicates which stain the cell contains. Cells displaying the desired characteristics are identified and counted. Finally, the fluid stream is divided into many miniscule droplets. Droplets which contain a desired cell are electrically charged and diverted by an electric field into different collecting tubes. The various separated cells can subsequently be investigated using microscopy, biochemistry and functional experiments.

The service
All research groups at the Biozentrum are invited to use the services of the facility and receive advice for upcoming experiments. They will be supported and guided in the planning and carrying out of experiments as well as the subsequent analysis. Besides support and teaching, the service facility FACS is concerned with further development and optimization of various aspects of the FACS methodology.