Liquid nitrogen tanks are usually filled with cryogenic liquid nitrogen. Cell storage requires a cryogenic environment. A suitable environment for cell long-term preservation is to put in liquid nitrogen at - 196 degrees. Conventional liquid nitrogen tank is to store cells in liquid phase of liquid nitrogen tank. There is a special square drawer basket. 2 ml freezing tube is put into the freezing box and then put into the basket, then immersed in liquid nitrogen, and completely immersed. Only when the cells are completely exposed to liquid nitrogen - 196 degrees can they be preserved for a long time.

 Another is gas storage, gas storage, the temperature is higher than liquid storage, but can also reach - 190 degrees, for cell storage, is enough. It can also solve some problems which are often encountered and unavoidable in liquid phase storage cells for a long time, such as sample contamination, tube explosion and so on.

 Relatively speaking, liquid nitrogen tanks of the same volume have a longer storage time than vapor tanks. The temperature of vapor phase freezing is slightly higher, but the storage time of liquid nitrogen tanks of the same volume is shorter (the amount of liquid nitrogen is less, so the frequency of adding liquid nitrogen is higher). The vapor phase needs to add liquid nitrogen frequently.