Trypan blue exclusion test

The Trypan blue exclusion test is a method to determine if cells are alive or dead. It involves adding a special dye called Trypan blue to a cell sample. Living cells have intact membranes that keep the dye out, so they remain unstained and appear clear under a microscope. Dead cells, however, have damaged membranes that allow the dye to enter, causing them to turn blue. By counting the number of stained versus unstained cells, scientists can assess cell viability. This simple test helps researchers evaluate cell health in experiments or in medical diagnostics.