Methods and devices for freeze-drying a biological sample of mammalian cells or tissue are disclosed. A method may include placing a biological sample on or in a structure such as a pre-cooled metal surface to decrease a temperature of the biological sample and with the biological sample in a closed chamber applying a vacuum to the chamber to lower a pressure within the chamber, cooling the chamber to lower a temperature within the chamber and applying heat to the biological sample within the chamber. The biological sample can include one or more of stem cells, hematopoietic stem cells, mesenchymal stem cells, embryonic stem cells, induced pluripotent stem cells, sperm, oocytes, embryos, ovarian tissue, uterine tissue or testicular tissue. A method for rehydrating samples is also disclosed.