Flow cytometry is a quantitative technique measuring the amount of cellular constituents on a single cell basis.

Flow cytometer Gallios Coulter Beckman

The constituents are labeled with a fluorescent molecule in a stoichiometric manner, i.e. the amount of bound fluorochromes is proportional to the amount of the cellular molecules to be quantitated. With appropriate illumination, the amplitude of the fluorescence signal detected is proportional with the amount of the cellular molecules. Several cellular constituents can be labelled thereby measuring simultaneously multiple cellular molecules.

The flow cytometer also detects the light scatter signal both in the forward direction which represents the size of the cell and in the direction perpendicular to the laser which reflects the granularity and internal structure of the cell.

The flow cytometer is equipped with four lasers

• 405 nm
• 488 nm
• 561 nm
• 638 nm and 10 detectors