Flow Cytometry

Dot Plot

A dot plot is a two parameter data graph used for acquisition of data and also for analysis. Each dot on the display represents one event that the flow cytometer analyzed. Dot plots can also quantitate percentages of cells with various properties. In addition, dot plots can show intensities. Stokes shift in luminescent spectroscopy, is a displacement of spectral lines or bands toward longer wavelengths (lower frequencies) than those of the corresponding absorption lines or bands (difference between 2 lines). Physical constraints imply that to maintain focusing for particles of cellular dimensions the stream requires a velocity of several metres per second. At this speed a typical cell would traverse its own diameter in a few microseconds which necessitates a rapid analytical system. This usually employs a highly focused laser beam for excitation and sensitive photomultiplier tubes (PMTs) for detection. Receive fluorescence signals.

References

1. Janeway, C.A., Travers, P., Walport, M., and Capra, J.D. 1999. Immunobiology: The immune system in health and disease. Garland Publishing, 4th ed., New York, USA