cell and tissue culture - healthy test (Dec/13/2008 )

Any of you know whether there is a dye or other agents that can be used to test whether culture cell, tissue are healthy or dying?
Thanks

there are a variety of tests that will tell you if you have specific cell death pathways activated, especially for caspase-3 mediated apoptosis. General cell death can be assayed by MTT assay or trypan blue staining. B-gal assay will tell you if your cells are dying/dead.

All these tests kill you cells in the process though, so there is nothing short of FACS with collection of live cells that will eliminate dead cells.