Nuclear Stain: is a stain selective for cell nuclei, usually based on the binding of a basic dye to DNA or to nucleohistone. Cell-permeant nuclear stains can be used to label nuclei in live cells that have intact, nonpermeable plasma membranes. These dyes will also stain nuclei of cells with compromised membranes such as dead cells or cells that have been fixed and/or permeabilized.