Use Method and Precautions of Freezing Tube
In microbiological experiments, one experimental equipment is often used, that is, the cryopreservation tube. However, due to their different complexity, the effects vary greatly. For this reason, at present, most laboratories in China make bacteria preservation tubes by themselves, which not only increases the work intensity, but also because of the limitations of various conditions, the effect of bacteria preservation is not always satisfactory.
Therefore, it is necessary to master the use method and some precautions of the cryopreservation tube, so as to play a great role.
1.Method of application
1). When using the cryopreservation tube to store samples, it is strictly required to put the cryopreservation tube into the vapor layer of liquid nitrogen or the refrigerator for storage. If the cryopreservation tube is stored in liquid nitrogen, there is a certain probability that the liquid nitrogen will infiltrate into the cryopreservation tube. During the recovery, the gasification of liquid nitrogen will lead to the imbalance of internal and external pressure, which is very likely to cause the cryopreservation tube to burst, and has biological hazards.
2). Operate the cryopreservation tube to resuscitate, and use safety protection equipment throughout the process. It is recommended to wear laboratory clothes, cotton gloves and operate on a safe laboratory bench. If possible, please wear goggles or face shield. As the indoor temperature in summer will be higher than that in winter, please be careful.
3). During the storage of cryopreserved cells, the freezing temperature of cryopreserved tubes must be uniform. Uneven freezing will lead to ice jam, which will inhibit the transmission of liquid temperature on both sides, thus generating dangerous high pressure and causing damage to the freezing tube.
4). The amount of frozen samples shall not exceed the maximum working volume required by the frozen tube.
2. Matters needing attention
1). Freezing tube storage environment
Unused cryopreservation tubes can be stored at room temperature or 2-8 ℃ for 12 months; The inoculated cryopreservation tube can be stored at – 20 ℃ and have a good effect of strain preservation within 12 months; The inoculated cryopreservation tube can be stored at – 80 ℃, and the strain can be preserved well within 24 months.
2). Freezing tube storage time
Unused cryopreservation tubes can be stored at room temperature or 2-8 ℃; The inoculated cryopreservation tube shall be stored at – 20 ℃ or – 80 ℃.
3). Operation steps of freezing tube
Take fresh cultures from pure bacterial cultures to prepare bacterial suspension with a turbidity of about 3-4 McDonnell’s ratio for inoculation and strain preservation tube; Tighten the preservation tube and reverse it back and forth 4-5 times to make the bacteria emulsified, without rotating; Put the preservation tube into the refrigerator for preservation (- 20 ℃ – 70 ℃
Post time: Nov-25-2022