Cell Death Screening Using DAPI Staining: A Method for Rapid Screening of IR Induced Clonogenic Cell Death in Cancerous Cell Lines

Take the cells from the incubator and aspirate the culture medium from the culture dish. Cut the tip of a 1,000-microliter micropipette tip about 5 millimeters from the end using scissors, and use it to add 1 milliliter of fixation solution to the culture dish.

Apply the fixation solution along the walls of the culture dish to minimize damage to the cells. Then, transfer this culture dish into a square culture dish and shake it gently to evenly distribute the fixation solution over the coverslip. After that, incubate the dish for 10 minutes at room temperature.

Aspirate the fixation solution from the dish. Now, add 2 milliliters of PBS along the walls of the dish and then aspirate the PBS. To prepare for DAPI staining, add 5 microliters of DAPI staining reagent onto a glass slide. Then, remove the coverslip from the dish using a scalpel and drain excess PBS on the coverslip by touching the edge of the coverslip with a paper towel.

Now, mount the coverslip upside down on the drop of DAPI staining reagent on the glass slide so that the cells are exposed to the DAPI staining reagent. Finally, examine the stained cells under a fluorescence microscope equipped with a DAPI filter.