Comparison of the advantages and disadvantages of two methods of high temperature sterilization: wet heat sterilization PK dry heat sterilization

Note: In the dry state, due to the poor heat penetration, the microbial heat resistance is high, and it is necessary to be subjected to high temperature for a long time to achieve the purpose of sterilization. Therefore, the dry hot air sterilization method generally uses a higher temperature than the moist heat sterilization method. Generally, it is sterilized for 3-5 hours at 135-145 °C; 2-4 hours at 160-170 °C; and 0.5-1 hour at 180-200 °C.

Wet heat sterilization (specifically, autoclaving): refers to a method of killing microorganisms by heating with high-pressure saturated steam.

Features: strong penetrating power, high sterilization efficiency and short time. The method is applicable to all pharmaceutical preparations, liquid culture media, textiles, glass containers, metal containers, porcelains, rubber stoppers, membrane filters and the like which are resistant to high temperature and high pressure steam. It is usually sterilized at 121 ° C for 20 min and sterilized at 134 ° C for 7 min.

MMM Group Damp Heat Sterilizer

Next, we will focus on the advantages and disadvantages of high temperature dry heat and high temperature wet heat.

1 The temperature required for protein coagulation is related to its water content. The higher the water content, the lower the temperature required for solidification to occur. The moist heat-sterilized bacterial protein absorbs moisture, so it is easy to coagulate in dry hot air at the same temperature.

2 During the moist heat sterilization process, the steam releases a large amount of latent heat, which accelerates the humidity. Thus, moist heat sterilization is lower than the temperature required for dry heat, and at the same temperature, the time required for moist heat sterilization is shorter than dry heat.

3 The penetration of damp heat is larger than that of dry heat, so that the deep part can also reach the sterilization temperature, so the damp heat is better than the dry heat.

Therefore, high temperature sterilization is not a simple look at the sterilization temperature, mainly to see if it is hot and humid. High-temperature damp heat has high latent heat and strong penetrating power, which tends to denature or solidify proteins. Therefore, the sterilization efficiency of this method is higher than that of dry heat sterilization.