Centrifuge and resuspend the cells in a suitable freezing medium at a density of 1-4×10⁶ cells/ml. - We recommend using Cryo‑SFM Plus, a defined, animal‑component‑free and protein‑free cryopreservation medium. - The freezing medium should be pre‑cooled to 4°C; room temperature (RT) should not be exceeded.
Cool the cells slowly to -80°C at an approximate rate of -1°C per minute. - We recommend using “Mr. Frosty” (Nalgene), which ensures gradual and controlled cooling when placed in a -80°C freezer overnight.
Transfer the vials to liquid nitrogen for long‑term storage.