Six commonly used sterilization methods are dry heat sterilization, wet heat sterilization, step sterilization, radiation sterilization, filtration sterilization and chemical reagent sterilization. Dry heat sterilization refers to the technology of sterilization in a dry environment (such as flame or dry heat air). Wet heat sterilization refers to the method of sterilization with saturated steam, boiling water or circulating steam. Step-by-step sterilization refers to the method of repeated heating by circulating steam, thus killing all microorganisms.

1. What are the six common sterilization methods?

1, dry heat sterilization: refers to the technology of sterilization in dry environment (such as flame or dry heat air). Generally, there are flame sterilization and dry hot air sterilization, which are suitable for drying powder, vaseline, grease and so on. Flame sterilization refers to the sterilization method of direct combustion with flame; Dry hot air sterilization refers to the method of sterilization with high temperature dry hot air.

2. Wet heat sterilization: refers to the method of sterilization with saturated steam, boiling water or circulating steam. Wet-heat sterilization method takes high-temperature and high-pressure steam as the medium. Because of the high latent heat and strong penetration of steam, protein is easy to denature or solidify, leading to microbial death. The sterilization efficiency of this method is higher than that of dry heat sterilization, and it is also a common sterilization method in the production of pharmaceutical preparations.

3. Step-by-step sterilization: refers to the repeated heating by steam, thus killing all microorganisms. Intermittent sterilization is generally carried out in a sterilization pot with flowing steam, and ordinary aluminum pot can also be used instead. This method is mostly used for sterilization of gelatin, milk and other substances. These substances will be destroyed if they are treated at a temperature above 100℃ for a long time. Step-by-step sterilization can play a role in sterilization and prevent the treated substances from being destroyed.

4. Radiation sterilization method: It is an effective method to kill microorganisms on most substances by ionizing radiation. They can control the growth of microorganisms or kill microorganisms in a specific way. For example, microwaves can kill microorganisms by heating. This method can be carried out at room temperature or low temperature, and the temperature rise of food during processing is very small, which is conducive to maintaining the quality of food; And the irradiated food will not leave any residue.

5. Filter sterilization method: it is to remove bacteria in liquid or air by physical retention, so as to achieve the purpose of sterility. The principles of filtration sterilization include inertial impact interception, interception interception and Brownian diffusion interception.

6. Chemical reagent sterilization method: refers to the method of killing microorganisms by directly acting on them with chemicals. This method can be divided into gas sterilization and liquid sterilization. Gas sterilization refers to the method of sterilization with gas bactericides such as ozone and formaldehyde. Liquid sterilization refers to a method that is easy to disinfect with bactericide.

Second, the scope of application of six sterilization methods

1. Dry heat sterilization method: it is suitable for sterilization of articles that are not damaged, deteriorated or evaporated at high temperature and instruments that are not resistant to damp heat. Used for sterilization of articles that are impermeable to steam or gas, such as glass, grease, powder, metal, etc.

2. Wet-heat sterilization method: it is suitable for high-temperature and wet-heat resistant articles, such as culture media and animal carcasses. Such as the pressure steam sterilizer commonly used in the laboratory.

3. Step-by-step sterilization: suitable for sterilization of heat-sensitive materials and preparations.

4. Radiation sterilization method: it is suitable for food, cosmetics, medicines, daily necessities, medical supplies, electronic plastics and other fields. Its main function is to disinfect the product. It can effectively reduce or kill different types of microorganisms in the product without unpacking.

5. Filter sterilization method: suitable for heat-resistant biological products such as serum, toxins and antibiotics and air sterilization.

6. Chemical reagent sterilization method: it is suitable for environmental disinfection and disinfection of medical instruments, equipment and facilities that are not resistant to heating sterilization, and also for powder injection.