Common sterilization methods in the medical industry: radiation sterilization, dry heat sterilization, moist heat sterilization, gas sterilization, filtration sterilization, ethylene oxide sterilization and ozone sterilization.
Radiation sterilization method refers to the sterilization of items placed in a suitable radioactive source of radiation gamma rays or suitable electron gas pedal electron beam for ionizing radiation to achieve the killing of microorganisms. Medical devices, containers, production aids, raw materials and finished products that are not damaged by radiation can be sterilized by this method.
Dry heat sterilization method refers to the items placed in the dry heat sterilization cabinet, tunnel sterilizer and other equipment, the use of dry hot air to kill microorganisms or eliminate pyrogenic substances. Suitable for high temperature but not suitable for sterilization with moist heat sterilization method
Sterilization of items, such as glassware, metal containers, fiber products, solid test drugs, liquid paraffin, etc. can be used in this method of sterilization.
Moisture heat sterilization method refers to the items placed in the pressure steam sterilizer using high-pressure saturated steam, hot water spray and other means of microbial organisms in the denaturation of proteins, nucleic acids and kill microorganisms. The method of sterilization ability, for heat sterilization in the most effective, most widely used sterilization method.
Filtering sterilization method to remove microorganisms in gas or liquid by using the principle that bacteria can not pass through the dense hollow filter material. Commonly used in heat unstable pharmaceutical solutions or raw materials sterilization.
Ozone sterilization, ozone is a strong oxidant, sterilization process is a biochemical oxidation reaction.
Gas sterilization method refers to the use of chemical disinfectants to form the gas kill microorganisms. Commonly used chemical disinfectants are ethylene oxide, gaseous hydrogen peroxide, formaldehyde, ozone (O3), etc. This method is applicable to the sterilization of stable items in the gas. When using the gas sterilization method, you need to pay attention to the flammability and explosibility of the sterilization gas, teratogenicity and residual toxicity.
The most commonly used gas sterilization method is ethylene oxide, ethylene oxide gas sterilization force, sterilization spectrum, can kill a variety of microorganisms including bacterial spores, is a sterilizing agent. It is a sterilizing agent. Generally, it is mixed with 80%~90% inert gases and used in a high-pressure chamber filled with sterilizing gases.
Ethylene oxide will not damage the sterilized items and penetration is very strong, generally used for medical equipment, plastic products and other items that can not be sterilized by high temperature sterilization. For example, electronic instruments, optical instruments, medical equipment, books, documents, fur, cotton, chemical fiber, plastic products, wood products, ceramics and metal products, endoscopes, dialyzers and single-use diagnostic and treatment supplies. Ethylene oxide is also one of the most important low-temperature sterilization methods available. Special attention should be paid to chlorine-containing articles and articles that can adsorb ethylene oxide should not be sterilized by ethylene oxide.
Ethylene oxide sterilization, sterilization cabinet temperature, humidity, sterilization gas concentration, sterilization time is an important factor affecting the sterilization effect.
Ethylene oxide sterilization needs to meet the following sterilization conditions:
Temperature (54±10)℃
Relative humidity (60±10)%
Sterilization pressure 8*10〈5〉Pa
Sterilization time 90min
Sterilization conditions should be verified Sterilization, the chamber will be first pumped into the vacuum, and then When sterilizing, the sterilization chamber is first evacuated into vacuum, then steam is introduced to make the chamber reach the rated value of temperature and humidity equilibrium, and then ethylene oxide gas which is filtered and preheated is introduced. During the sterilization process, the chamber temperature, humidity, pressure, ethylene oxide concentration and sterilization time should be closely monitored. Use biological indicators to monitor the sterilization effect if necessary.
The control of the sterilization procedure of this method is difficult, and the whole sterilization process should be carried out under the supervision of skilled personnel. After sterilization, fresh air replacement should be taken to dissipate residual ethylene oxide and other volatile residues. And the ethylene oxide residues and reaction products in the sterilized articles are monitored to prove that they do not exceed the specified limits to avoid toxicity.