how are dead cells removed

Hello
usually if you are culturing cells, dead cells will be floating in the supernatant after centrifuging the cells into a pellet. Only live cells descend to the bottom to make a pellet. Therefore, by just removing the supernatant, you're likely to eliminate the majority of the dead cells.
Also, dead cells exhibit in some cases phosphatidyl serine residues outisde the cell membrane. By targeting this residue, you may by the priniciple of antibody-antigen binding, sort live from dead cells.
Another method would be to stain cells and sort them using flow cytometry.
These are the techniques I could remember off the top of my head.
But the most common method used is just getting rid of the supernatant. Afterall, flow cytometry and stains and antibodies are expensive. To utilize them just for sorting dead cells would be somewhat non-practical.

I hope this helps

Thanks for helping me

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