In this method the staining
procedure is performed with fluorescent substances
like Hoechst dye 33342, DAPI or Propidium
Iodide. As florescent dyes are bound to DNA, the
chromatin, and as such, the nucleus of the cell becomes
visible. Fluorescence systems are considerably
more expensive than light microscopy, but if used
in cellular culture studies, they may be beneficial in
differentiating live cells from dead cells. However,
in samples where Giemsa or hematoxylin staining is
used, all cells are observed dead due to the fixation
of cells.