Fig. 4.

Comparison of the cell viabilities after thawing under varying conditions. (A) Bar 1 was obtained from a conventional freezing method, while bars 2–7 were obtained from the SFF method in the absence of CPAs. The highest viability was obtained from freezing 40-pL droplets on a 5-μm-thick substrate (bar 5). Bars 6 and 7 refer to a method wherein the frozen cells were once transferred to the vapor phase of LN and thawed immediately or 5 d thereafter (n = 5). (B) Doubling times for the first and second divisions of 3T3 cells. Both first doubling times were longer than the general doubling time for 3T3 cells (20–24 h). The doubling times of the second divisions were comparable to the general one. A significant difference was not detected for the first and second doubling times between the SFF method and the conventional method (n = 5).