Cold Sterilizer

Content
1. What is cold sterilizer?
    1.1. Definition of cold sterilizer
    1.2. Cold sterilzier appilication
2. Cold sterilization solutions
    2.1. Hydrogen peroxide solution
    2.2. Peroxyacetic acid solution
    2.3. Glutaraldehyde solution
3. Types of cold sterilizer
4. Cold sterilzer specifications
    4.1. Hydrogen peroxide plasma sterilizer
    4.2. Glutaraldehyde cold sterilizer
5. How to use cold sterilizer?
6. Precautions for using cold sterilizer
7. How to order cold sterilizer?

Cold sterilizer is a kind of sterilization equipment used to process medical devices and items that are not resistant to heat and humidity. The rapid changes in medical science and technology have led to the gradual promotion of various precision instruments and equipment, which often cannot be autoclaved because they cannot withstand high temperatures. In order to solve this problem, various cold sterilization methods and sterilization equipment are gradually produced.

The application of cold sterilizer can choose different sterilization methods according to the nature of the sterilized items: pressure steam sterilization should be preferred for moisture-resistant and heat-resistant medical instruments, appliances and items; dry powder sterilization should be used for heat-resistant oils and dry powders; low-temperature sterilization methods should be used for items that are not heat-resistant or moisture-resistant, such as ethylene oxide sterilization, hydrogen peroxide low-temperature plasma sterilization or low-temperature formaldehyde steam sterilization.

At present, the world's recognized cold sterilization solutions mainly include the following: glutaraldehyde, acidified water, peroxyacetic acid, ethylene oxide sterilization, hydrogen peroxide low-temperature plasma sterilization, low-temperature steam formaldehyde sterilization, etc.

The bactericidal effect of hydrogen peroxide solutions has been recognized for more than 100 years. Many studies have proved that H2O2 solutions at certain mass concentrations have a killing effect on bacteria, fungi, viruses and bacteriophages. Hydrogen peroxide is a strong oxidizing agent, which can form free hydroxyl groups and active derivatives with strong oxidizing ability.
The bactericidal mechanism of hydrogen peroxide can be divided into 2 categories: destruction of the outer protective structure of microorganisms, making changes in the permeability of the protective layer, thus causing changes in cellular osmotic pressure, microorganisms die due to the disruption of the balance system outside the body; by destroying the enzymes, proteins and DNA in microorganisms to make microorganisms die.

Peroxyacetic acid solution, which has become a substitute for glutaraldehyde in some countries, is used extensively in the European Union, where it kills a wide range of microorganisms very quickly. The bactericidal spectrum includes bacterial germ cells, and unlike most liquid sterilants, the activity of peroxyacetic acid is not affected in organic environments. In addition, peroxyacetic acid has a high occupational safety level and no limit values for exposure concentrations. The biggest disadvantage of peroxyacetic acid is its corrosiveness, causing rubber deterioration, etc. In Europe, peroxyacetic acid is mainly used in ternary packages, one of which is a preservative component that significantly reduces corrosion, for endoscopic sterilization. Delete, this is not the method of hospital sterilization.

Since the discovery of glutaraldehyde's apparent bacteriocidal activity in aldehyde compounds in 1962, many scientists have conducted extensive and in-depth research on its physicochemical properties, bactericidal activity, clinical application and toxicity. In clinical use, glutaraldehyde has the advantages of broad bactericidal spectrum, high efficiency, weak corrosiveness, good stability, etc., and is inexpensive and easy to obtain.
It has been found that the activity of glutaraldehyde disinfectants is easily affected by pH, temperature, formulation type, placement time, dilution of concentration during use, cross-linking reaction of glutaraldehyde itself, and special insensitive pathogens, etc. It is worth noting in clinical use. Since glutaraldehyde concentration < 1%, many pathogenic bacteria will develop resistance, so in clinical use, the common concentration is 2%.
However, due to the influence of many factors in use, such as the dilution effect of wet instruments in use, it is also necessary to monitor the concentration of glutaraldehyde before use every day to make sure it meets the relevant national standards. The use of glutaraldehyde is limited by the adverse effects of glutaraldehyde, the fact that it can only be used on soakable instruments, and the time required for sterilization. 2% glutaraldehyde solution has a significant irritating effect on human skin and mucous membranes, and is a heavy irritant to the eyes and upper respiratory tract. There have been case reports of allergic reactions and systemic adverse reactions. Personal protection, especially eye and respiratory protection, should be strengthened in clinical use, such as eye protection against splashing and good ventilation in the room. Glutaraldehyde is banned in some European countries due to occupational safety factors, and the clinical use of collaterals (OPA) and peroxyacetic acid (PAA) is gradually emerging as alternatives.

Ethylene oxide cold sterilizers can be divided into mixed gas and 100 % pure ethylene oxide low-temperature sterilization systems and all of them are 100 % pure ethylene oxide low-temperature sterilization systems. 　
Ethylene oxide can kill various microorganisms such as bacteria (including Mycobacterium tuberculosis), bacilli, fungi, rickettsiae, viruses, etc. It is a broad-spectrum bactericide. Its sterilization mechanism is to combine amino, hydroxyl, carboxyl, or sulfhydryl groups in bacterial protein molecules, enzymes, and nucleic acids to produce irreversible damage to the metabolism of the bacterium cells, thus achieving the sterilization effect.

Since the hydrogen peroxide plasma cold sterilizer is still in the research stage, there is no accepted theory on its sterilization mechanism. Some scholars believe that the bactericidal effect of hydrogen peroxide plasma is due to a combination of factors, including temperature, ultraviolet light, high-energy particles, and active radicals. Among them, the most important may be the role of active radicals, that is, the plasma group of hydrogen peroxide, hydroxyl groups, and other active substances, easy to bind with bacteria in the body of proteins and nucleic acids, disrupting their metabolism, thus playing a sterilizing effect.

The mechanism of formaldehyde killing microorganisms is mainly alkylation, the aldehyde group in the formaldehyde molecule can react with the amino group, carboxyl group, hydroxyl group, and sulfhydryl group in microorganism protein and nucleic acid molecule, to destroy the activity of microorganism molecule and make it die. It has the effect of killing bacteria and budding spores.

Glutaraldehyde cold sterilizer replaces the cold steam formaldehyde sterilizer which is harmful to the human body and is a new generation of sterilization equipment controlled by microcomputers.

Features:
1. The sterilization temperature of hydrogen peroxide plasma sterilizer is stable and harmless to the instrument, which can prolong the service life of the equipment.
2. The sterilized material is water and hydrogen molecules, which is not toxic to the operator.
3. The fastest sterilization time is 25 minutes and can be used directly after sterilization without any treatment.
4. Highly intelligent control system, easy to operate.

Features:
1. Glutaraldehyde cold sterilizer has its own microcomputer control component, timing temperature control, one key operation, convenient operation.
2. Made of thicker plate material, thicker material at the partition, longer service life.

The use of hydrogen peroxide plasma sterilizer and glutaraldehyde cold sterilizer are different, so when using different cold sterilizers, the following points should be noted respectively:

* Preliminary stage
①　Cleaning: The sterilization effect of hydrogen peroxide is greatly affected by inorganic salts as well as organic matter such as blood, so the instruments must be cleaned before sterilization.
②　Drying: The instruments need to be vacuumed before sterilization, so the instruments must be kept dry so that the sterilization cycle will not be interrupted during the sterilization process and the vacuum will be repeated.
③　Packaging: Wrap the instruments in sterilization bags and put chemical indication cards inside the package. The whole set of instruments or lumpectomy class should be put into instrument boxes or instrument baskets (if there are tube cores, they need to be taken out and placed in parallel first), and then wrapped with two layers of non-woven fabric in the outer layer.
* Sterilization stage
①　Placement: Place instruments in single layer side by side in sterilization baskets, the transparent side of the bags must be kept facing the same direction and there should be gaps between instruments. Try to place different types of instruments in different categories and do not mix them. Then place the sterilization baskets in a single layer flat on the metal shelf in the sterilization room.
②　Selecting the cycle: Select the sterilization cycle according to the type of instruments. Choose primary cycle for instruments with small quantity, simple shape and clean surface; choose secondary cycle for instruments with complex structure or with tube lumen.
③　Wait for the end of sterilization and judge the sterilization effect according to the indicator card: the indicator card is gray before sterilization, and the indicator card turns light red after sterilization.

①　Pour 2% alkaline glutaraldehyde into the tank must not be poured out, otherwise it will seriously affect the life of the heater and short circuit problems.
②　As it will volatilize soon after heating, you should often see the consumption in the liquid tank and do not use the liquid tank without operation.
③　Glutaraldehyde products from different manufacturers cannot be mixed or postponed, otherwise, it will easily produce precipitation and affect the sterilization effect.
④　After fumigation, glutaraldehyde will produce residual crystals, which are brown and attached to the wall of the shell, which can be regarded as rust spots, and users should clean it regularly every week, especially the cabinet door and the location of the sealing strip inside the cabinet where the contact surface between themselves and others is placed. As a result of a long time without cleaning occurs adhesion, easy to leads to seal leakage damage.
⑤　Items should be cleaned aseptically by hand before fumigation.
⑥　Aseptically stored items should be cleaned again after more than five days.

1. The cold sterilizer should be installed in a clean area and kept at a sufficient distance from the surrounding walls (generally more than 10m).
2. The sterilized object must be thoroughly cleaned and fully dried before sterilization.
3. When using the plasma peroxide sterilizer, long and thin catheters with blind ends, instruments with lumen lengths greater than 2m or internal diameters less than 1mm, plant fiber products, liquids,and powders cannot be sterilized with the plasma cold hydrogen peroxide sterilizer.
4. Packaging shall be in bags or polypropylene non-woven fabric and shall not be reused.
5. Sterilization objects should be placed in a way that facilitates the penetration of the sterilizing agent and should not be stacked.
6. The equipment should be maintained and serviced in strict accordance with the sterilizer manual.

If you are interested in our cold sterilizer or have any questions, please write an e-mail to [email protected], we will reply to you as soon as possible.