For rapid detection of cell number and size we use the CASY cell counting technology. Living cells, having an intact membrane are electric insulators. During measurement cells are passing through a pore and are exposed to an electric field. Being electric isolators cells increase the electric resistance in the pore, depending on  the cell size. Dead cells are measured with the nucleus size. With help of the CASY Counter we are able to measure (i) cell number, (ii) cell size distribution.