Optical principle: Automated systems are now based on flow-through (also called flow cytometry) opticaltechnologies that identify cells on the basis of light scatter properties broadly equating to the cell’s physical characteristic differences.
Blood cell recognition is optimized by diluting specifically to the number of cells present in the blood so as to count the number of cells appropriate for statistical accuracy.
A focused light beam illuminates a small area of a flow cell. Cells are rapidly injected in single file (hydrodynamic focusing) through the illuminated area (interrogation zone) where the cells intersecting the light beam scatter light in all directions in a manner that is measurable and unique to each cell type.
The resulting light scatter information can be collected at multiple locations incident to the light beam providing a multi-dimensional analysis of the unique light scatter properties from each cellular event. Analysis and displays of the optical light scatter measurements are provided in a two-dimensional graphical form called a scatterplot.Multiple scatterplots may be generated for complete visualization of all the cellular components including sub-populations of each cell line.