A new method for fast blood cell counting and partial differentiation by flow cytometry.

A new blood counting method by flow cytometry is described which determines absolute counts and relative proportions of erythrocytes, reticulocytes, thrombocytes, lymphocytes and granulocytes from one sample of saline diluted human or animal blood. Staining time is 2 to 5 min and measuring time between 1 and 2 additional minutes. Measured simultaneously are the electrical cell volume, the green and optionally also the red fluorescence of the transmembrane potential sensitive dye 3,3-dihexyloxacarbocyanine DiOC6(3) and the RNA/DNA stain acridine orange (AO). Work is under way to fully automate staining, measurement and data evaluation. The use of stains by which blood cell counting and biochemical analysis can be combined offers new possibilities for routine blood cell counting without requirement for additional time. The potential of such stains is that pathologic cell conditions which are not, or not yet reflected in the cell count may be earlier detectable by biochemical stains.