Ethylene oxide sterilization supplier

Ethylene oxide (EO) has been used for hospital sterilization since the 1950s. The research of many scientists has proved that ethylene oxide is considered to be a low-temperature chemical sterilant with good sterilization effect. Sterilization of hot and humid medical device products.

1.1 The principle of sterilization

EO is a simple epoxy compound, which can form ethylene glycol in contact with water, has a large vapor pressure, and has strong penetrability to articles. According to reports, EO5min can penetrate 0.1mm thick nylon film, 26min can penetrate 0.3mm thick neoprene cloth, 41min can penetrate 0.39mm thick butyl rubber cloth.

If a certain sterilization effect is to be achieved, the sterilant must fully contact all surfaces of the article, and the high penetration of EO greatly improves its sterilization effect. EO has a killing effect on various microorganisms such as bacteria, spores, fungi, rickettsia and viruses, and belongs to the spectrum bactericide. Its sterilization mechanism is to combine with amino, hydroxyl and carboxyl groups in bacterial protein molecules, enzymes and nucleic acids. , resulting in alkylation, irreversible damage to the metabolism of bacterial cells, so as to achieve sterilization.

1.2 Sterilization Validation

Validation of ethylene oxide sterilization consists of the following 3 steps:

Installation confirmation: First, confirm the integrity of the sterilizer accompanying documents and accessories, such as installation records, drawings, computer software, calibration of measuring devices, etc.; second, verify the compliance of the sterilizer working environment, such as water quality testing, Safety requirements, etc.; the third is to verify whether the sterilizer installation meets the equipment installation requirements, and to confirm the concentration and quality of the sterilant.

Operational Validation: Verification of the ability of the sterilization equipment to provide specific processes within specified tolerances, such as temperature profile testing, humidity profile testing, leak testing, vacuum rate testing, air circulation testing (if used), etc.

Performance verification: including physical performance verification and microbial performance verification.

Validation of physical properties should be documented to demonstrate that the process is reproducible and conforms to all specified acceptable parameters. These processes include pretreatment, treatment, sterilization, and aeration stages, etc. The validation of operational reproducibility generally requires at least 3 consecutive runs, with microbial challenge tests as appropriate. Ethylene oxide is a carcinogen, and the effects of ventilation times and the temperature and time of desorption placement on the residual ethylene oxide also need to be evaluated accordingly.

The purpose of microbiological performance verification is to demonstrate in writing that after the sterilization process, the sterility performance of the product has reached the specified requirements (SAL=10-6).

The methods of microbial performance verification are: bioburden method and over-sterilization method. In general, biological indicators (BI, Bacillus subtilis spores) are used to confirm the microbial performance of EO sterilization. Products subject to microbiological performance verification should use the same packaging as their routine sterilization. This position is maintained throughout the sterilization cycle.

The number of biological indicator monitoring points should be able to verify the microbial inactivation of all sterilized items in the sterilizer. Usually, when the volume of the sterilization chamber is less than or equal to 10m3, at least the volume V × 3 detection points should be set during verification, but not less than 5. For daily monitoring, set at least V×1.5 detection points, but not less than 5.

When the volume of the sterilization room is more than 10m3, at least 30+(V-10)×3 test points should be set during verification, and at least 15+(V-10)×1.5 test points should be set for daily monitoring. This also involves requirements such as the number of temperature and humidity probes. Different volumes of sterilizers have different requirements. Please refer to ISO 11135.

Since there are no universal classical sterilization parameters for ethylene oxide sterilization, there are many factors that affect the sterilization effect and are interrelated, and the control of the sterilization process is complicated. Therefore, in order to ensure the sterilization effect, the strict verification of the sterilization process is necessary. In addition, if any one of the factors of the sterilization equipment, the items to be sterilized and the loading method are changed, it needs to be re-validated.

1.3 Product release

In daily monitoring, it is necessary to monitor the temperature and humidity during pretreatment, the humidity and time in the sterilization cabinet during processing, the temperature and pressure of the entire sterilization process, the evidence that ethylene oxide has been injected, the sterilization time, and the analysis time. temperature and pressure changes. Finally, the product can only be released if all biological indicator (BI) cultures are negative and the sterilization process parameters are within the parameters of the performance verification.

1.4 Application

EO can be used for the extinction of items that are not resistant to high temperature and moisture. It is considered to be a chemical sterilant with the best sterilization effect, which can kill all microorganisms including bacteria and spores. EO has strong penetration and can be used for sterilization of various difficult-to-penetrate parts. For example, some thinner and longer catheters are difficult to achieve sterilization effect by other low-temperature sterilization methods, and only EO or radiation can be selected. According to.

EO sterilization also has less damage to items. Sterilization uses the principle of alkylation rather than oxidation, and has a very broad application prospect for heat-labile materials and equipment. When using EO sterilization, it can be wrapped with various wrapping materials, which is convenient for storage and transportation. It can be used after opening the package to avoid the risk of cross-contamination. In the sterilization process, there are standard chemical and biological monitoring methods, which can effectively control of sterilization quality.

EO has a wide range of clinical uses. Equipment and products sterilized with EO include:

Rigid and flexible endoscopy, such as: arthroscopy, bronchoscopy, cystoscopy, gastroscope, colonoscopy, ophthalmoscope, otoscope, urethroscope, thoracoscope, etc.;

Medical equipment, such as: anesthesia equipment, artificial kidney, diathermy equipment, wires, watch heads, heart-lung machines, hemodialysis, etc.;

Instruments: electric drill, electric burner, dental drill, microsurgery, nerve stimulator, pressure gauge, shell surgery, bone drill, needle, artificial joint, etc.;

Rubber products: catheters, dilators, drainage tubes, endotracheal tubes, gloves, pacemakers, heart valves, nebulizers, etc.
we supply 2-120 cubic eto sterilizer, any need please email to info01@cnoilmachine.com