Cryopreservation

1. The measurement of survival or viability of the frozen materials can be performed at any stage of cryopreservation or after thawing or re-culture.
2. The techniques used to determine viability of cryopreserved cells are the same as applied for cell cultures.
3. The commonly used techniques are staining techniques using triphenyl tetrazolium chloride (TTC), Evan’s blue and fluorescein diacetate (FDA).
4. The entry of cryopreserved cells into cell division and regrowth in culture is the best indicator to measure the viability of them