Andreas Radbruch

Operation of a Flow Cytometer

Biomedical research, from the organism to the molecule and back again, requires powerful tools to analyse the functional status of individual cells, the unit of organisation of life. Cells have been detected by microscopy which, in combination with powerful staining technologies, is still the main instrument to obtain direct information on their state of activation, proliferation and differentiation. The drawback of microscopy is that the data generated are mainly “visual impressions” and not exact numbers. Today, systems are available that allow quantification of light intensity of microscopic objects, but these systems are still too slow to allow analysis of enough objects to obtain good statistics. One could say that microscopy generates too much information in cases, where only information on the amount of a particular stain per cell is desired.