Among the many cryopreservation equipment, liquid nitrogen tanks and cryogenic freezers are the two most common equipment. However, for many users, the choice between liquid nitrogen tanks and cryogenic freezers for cryopreservation remains a problem.
1. Temperature and humidity.
There are significant differences in temperature and humidity between liquid nitrogen tanks and cryogenic freezers. The temperature of the liquid nitrogen tank is generally -196, which is the liquefaction temperature of nitrogen. Since the liquid nitrogen in the tank is constantly evaporating, its humidity is also very low, generally less than 1%. This extremely low temperature and humidity is very beneficial for the cryopreservation of biological samples such as cells and tissues, which can effectively reduce cell metabolism and reduce cell damage.
In contrast, the temperature of a cryogenic freezer is generally around -80, which is a higher temperature. At the same time, the humidity of low-temperature refrigerators is also high, generally around 90%. This temperature and humidity may not be suitable for cryopreservation of some biological samples, especially during long-term cryopreservation, which may cause some degree of damage to the sample.
2. Storage space and number of samples.
There are also significant differences between liquid nitrogen tanks and cryogenic freezers in terms of storage space and number of samples. Liquid nitrogen tanks are generally small and have limited storage space, so only a small amount of sample can be stored. However, due to its extremely low temperature and good cryopreservation, liquid nitrogen tanks are a good choice for some samples that need to be frozen for a long time.
Cryogenic freezers have a large storage space and can store a large number of samples. At the same time, the temperature and humidity of the cryogenic freezer can also be adjusted as needed, so it is a better choice for some samples that need to be frozen in the short or medium term.
3. Ease of operation and safety.
In terms of ease of operation and safety, there is also a big difference between liquid nitrogen tanks and cryogenic freezers. The liquid nitrogen tank is easy to operate, and only the sample needs to be placed in the liquid nitrogen tank to start cryopreservation. However, due to the extremely low temperature in the liquid nitrogen tank, it can lead to safety issues such as frostbite or burning if not handled properly. Therefore, special attention needs to be paid to safety when using liquid nitrogen tanks.
Cryogenic freezers are relatively complex to operate and require temperature and humidity regulation and control. However, low-temperature refrigerators are more safe, and there are generally no safety problems such as frostbite or burning. At the same time, cryogenic freezers can also further improve safety by setting safety measures such as temperature alarms.
Fourth, cost and maintenance.
In terms of cost and maintenance, there are also certain differences between liquid nitrogen tanks and cryogenic freezers. Although the liquid nitrogen tank is more expensive to purchase, due to its low cost of use, it only needs to be replenished with liquid nitrogen regularly. At the same time, the structure of the liquid nitrogen tank is simple and the maintenance is relatively convenient.
In contrast, cryogenic freezers are less expensive to purchase but more expensive to use and require regular inspection and maintenance. At the same time, the power consumption of low-temperature refrigerators is also large, so special attention needs to be paid to energy saving.
To sum up, liquid nitrogen tanks and cryogenic freezers have their own advantages and disadvantages, and users can choose according to their needs. If a small amount of sample needs to be frozen for a long time, and the temperature and humidity requirements are high, the liquid nitrogen tank is a good choice; Cryogenic freezers are more suitable if you need to freeze large quantities of samples in the short or medium term, and the temperature and humidity requirements are not too high. No matter which equipment you choose, you need to pay attention to safety and maintenance issues during use.
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