Multiparameter Flow Cytometry

In a flow cytometer, cells in suspension are forced by hydrodynamic focussing to pass multiple detectors. At one given point of time, only one single cell is passing these detectors. There are detectors capable of registering changes in the impedance of the suspension as an indirect measure of the volume of the cells. Other detectors are capable of registering light signals emitted by the cells. Each signal generated by each single cell on any of these detectors is transformed into one single numerical value. Finally, each numerical value is subject to analysis by a software program, correlating each registered value to any defined cellular feature. Currently, all routine hematological counters are flow cytometers. Fixed, manufacturer-defined conditions are active for sample-processing within the device, fixed algorithms process the cell signals, and fixed analysis software produces the definite analysis.