Why are my mammalian cells dead after cryostorage in liquid nitrogen but not after storage in ultra low (-80) freezer?

I prepare cells for storage according to ATCC guidelines, usually 10% DMSO and 20% FBS. Cells are in cryostorage vials intended for use in liquid nitrogen. Cells are Hek293T, HepG2, HeLa and...

15 May 2019 7,948 3 View