Atmospheric pressure low-temperature plasma rapid sterilization device and sterilization method

Abstract

The present invention provides a plasma rapid sterilization device, including a sterilization chamber, an air inlet, an exhaust port, a grounding electrode, an electrode and a pulse power supply. The sterilization chamber has an inlet for an instrument to be sterilized, and the air inlet and the exhaust port inject atmospheric pressure gas into the sterilization chamber as a discharge medium. The sterilization chamber has a conductive layer, and the grounding electrode is connected to the conductive layer. The power output end penetrates the sterilization chamber and is insulated from the conductive layer. The power output end is connected to the pulse power supply on the outside and contacts with the instrument to be sterilized on the inside. The instrument to be sterilized serves as an electrode, and the operation is simple. Sterilization is carried out under atmospheric pressure, and there are few restrictions on the material and structure of the sterilization chamber, and there is no safety risk of pressure vessels. High-density plasma can be generated in the sterilization chamber, and the sterilization effect is good, which is particularly suitable for precise instruments that are not resistant to moisture and heat. The working gas is safe and has no residual hazards, and will not cause damage to the instrument and the operator. The sterilization cycle is short, which can meet the sterilization needs of instruments with short turnaround time requirements.

Description

Technical Field

[0001] The invention relates to a sterilization device, in particular to an atmospheric pressure low-temperature plasma rapid sterilization device which uses a device to be sterilized as an electrode. Background Art

[0002] With the continuous development of the medical device field, there are more and more high-precision electronic and optical devices in medical devices. They are of high value and frequently used. Many devices are not suitable for traditional moist heat sterilization or traditional sterilization methods can no longer meet the clinical use and device protection needs. However, various outpatient departments of hospitals and the central disinfection and sterilization supply room of hospitals have a large demand for sterilization of such devices.

[0003] Plasma is a collection of particles composed of electrons, ions and neutral particles, which are electrically neutral as a whole. Low-temperature plasma is usually produced by ionizing gas in an electric field. Because low-temperature plasma will not burn the processed objects due to its high electron energy and low gas temperature, and contains a large number of active atoms, molecules and free radicals, it is very conducive to chemical reactions, so it has been widely used in waste treatment, chemical synthesis, material processing, biomedicine and other fields.

[0004] For the conventional method of inactivating pathogenic microorganisms, the temperature of traditional wet heat sterilization methods such as pressure steam is relatively high, about 121.3℃, so it is impossible to sterilize medical devices that are not resistant to high temperatures, and the sterilization cycle is long, about 15-30 minutes. After high-pressure steam sterilization, it needs to be dried before it can be used. Therefore, it cannot meet the sterilization needs of various outpatient departments in the hospital. If ethylene oxide sterilization is used, the sterilization effect of this method is greatly affected by temperature and relative humidity. At the same time, ethylene oxide is flammable, explosive, and toxic to humans, so it must be carried out in a closed ethylene oxide sterilizer. The ethylene oxide sterilization procedure must include preheating, prehumidification, vacuuming, introducing gasified ethylene oxide to reach a predetermined concentration, maintaining the sterilization time, removing ethylene oxide gas in the sterilization cabinet, and analyzing to remove ethylene oxide residues in the sterilized items. On the other hand, ventilation is required after ethylene oxide sterilization before it can be used, generally for 24 hours. Therefore, the sterilization process using ethylene oxide is rather cumbersome, has certain safety risks, and cannot meet the hospital's sterilization time requirements.

[0005] Currently, medical devices are sterilized using hydrogen peroxide low-temperature plasma sterilizers on the market, which require pre-vacuum treatment. There are many pre-treatment steps, high costs, and a long sterilization cycle of about 45-50 minutes. At the same time, negative pressure vacuum may affect the performance of some high-precision instruments, thus limiting its scope of application.

[0006] Patent CN106693009A presents a method for sterilizing an atmospheric pressure flexible cold plasma jet endoscope. Its main feature is that the catheter-type sterilization area is non-enclosed and independent of the plasma electrode discharge area. However, this method may affect the sterilization efficiency because the sterilization area and the discharge area are separated by a certain distance. If the instrument can be directly used as an electrode, this method is easy to operate and can generate a higher density of plasma around the instrument for efficient sterilization, but the above-mentioned low-temperature plasma sterilization device has not yet been realized. Summary of the invention

[0007] The present invention aims to overcome the above-mentioned inadequacies and provides a low-temperature plasma rapid sterilization device that uses instruments directly as electrodes under atmospheric pressure.

[0008] The technical solution of the present invention is: an atmospheric pressure low-temperature plasma rapid sterilization device, comprising a sterilization chamber, an air inlet, an exhaust port, a grounding electrode, an electrode and a pulse power supply, wherein the sterilization chamber has an inlet for the instrument to be sterilized, the sterilization chamber has an air inlet and an exhaust port for the atmospheric pressure discharge working gas, the sterilization chamber has a conductive layer, the grounding electrode is connected to the conductive layer, the power supply output end penetrates the sterilization chamber and is insulated from the conductive layer, the power supply output end is connected to the pulse power supply on the outside and contacts with the instrument to be sterilized on the inside, and the instrument to be sterilized serves as an electrode.

[0009] Furthermore, the power output terminal penetrates from the exhaust port.

[0010] Furthermore, the sterilization chamber is made of quartz or ceramic material.

[0011] Furthermore, the conductive layer is located on the outer layer of the sterilization chamber.

[0012] Furthermore, the power output terminal is made of steel, tungsten metal or their alloys.

[0013] Furthermore, the discharge medium is helium or a mixed gas of helium-oxygen-hydrogen peroxide.

[0014] Furthermore, the air inlet and the air outlet are provided with valves.

[0015] The present invention also provides an atmospheric pressure low-temperature plasma rapid sterilization method, which uses the above-mentioned atmospheric pressure low-temperature plasma rapid sterilization device, and the method is as follows: the instrument to be sterilized is brought into contact with the output end of a power supply from the inlet of the instrument to be sterilized; atmospheric pressure discharge working gas is rushed in from the air inlet, and the exhaust port is opened at the same time to replace the air in the sterilization chamber; the air inlet and the air outlet are closed; the pulse direct current applied by the pulse power supply is turned on, and the conductive layer of the sterilization chamber is grounded at the same time, and plasma is generated by discharge in the sterilization chamber; the disinfection time is 5 to 15 minutes, and the temperature does not exceed 100°C; after the sterilization is completed, the air inlet and the air outlet valves are opened, air is rushed in from the air inlet, and the discharge medium is discharged from the air outlet.

[0016] Furthermore, the disinfection time is 9 minutes and the temperature is 80°C.

[0017] Beneficial effects:

[0018] 1. The sterilized instrument is directly used as an electrode, which is easy to operate.

[0019] 2. Sterilization is carried out under atmospheric pressure, which places little restriction on the material and structure of the sterilization chamber and does not pose any safety risk to pressure vessels.

[0020] 3. High-density plasma can be generated in the sterilization chamber, which has a good sterilization effect and can sterilize precision instruments that are not resistant to moisture and heat that cannot be sterilized by conventional sterilization methods.

[0021] 3. The working gas is inert gas helium or a mixed gas with a small amount of oxygen and hydrogen peroxide. It is safe and has no residual hazards and will not cause damage to the equipment and operators.

[0022] 4. The sterilization cycle is short, which can meet the sterilization needs of various outpatient departments of the hospital and the central disinfection and sterilization supply room of the hospital for instruments with short turnover time requirements.

[0023] 5. The present invention adopts low-temperature plasma technology, which can kill microorganisms with strong resistance to heat, radiation, and chemicals on the variable-diameter endoscope within less than 15 minutes under a normal pressure environment within 100°C. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 Schematic diagram of the device of the present invention. DETAILED DESCRIPTION

[0025] Example 1

[0026] This embodiment provides an atmospheric pressure low-temperature plasma rapid sterilization device, which can use inert gas helium or a mixed gas thereof mixed with a small amount of oxygen and hydrogen peroxide as the working gas, and utilizes the high-amplitude and high-frequency pulse DC voltage applied by a pulse DC power supply to discharge in the sterilization chamber to generate plasma. The breakdown effect of the charged particles in the plasma and the oxidation effect of the active oxygen play a major role in killing microorganisms, thereby achieving rapid and efficient sterilization under atmospheric pressure.

[0027] like Figure 1As shown, the above-mentioned device includes: a sterilization chamber 1, a grounding electrode 2, an air inlet 3, and an exhaust port 4. The sterilization chamber 1 has an inlet for the sterilized instrument 5, and the sterilization chamber 1 is made of a dielectric material such as quartz and ceramics. The power output terminal 7 is made of a high-temperature resistant metal such as steel, tungsten, or an alloy thereof. The air inlet 3 is connected to the sterilization chamber 1, and an atmospheric pressure inert gas helium or a mixed gas thereof mixed with a small amount of oxygen and hydrogen peroxide can be injected into it as a working gas 6, and the opening and closing is controlled by a valve. The sterilization instrument 5 to be sterilized is placed in the sterilization chamber 1, and the sterilization chamber 1 made of quartz, ceramics, etc. is used as a medium. The outer layer of the sterilization chamber 1 has a conductive layer and is connected to the grounding electrode 2, and the sterilized instrument 5 is directly used as an electrode. When the pulse power supply applies a high-amplitude and high-frequency pulse voltage, the voltage can be positive or negative. The power output terminal 7 penetrates from the exhaust port 4 and is isolated from the conductive layer. The pulse power supply is connected to the outside. After the inside contacts the sterilized instrument 5, a high-density plasma can be formed around the sterilized instrument 5 in the sterilization chamber 1. There are a large number of charged particles in the plasma, including positive and negative ions and active particles, etc. The device to be sterilized 5 in this embodiment is a medical device such as an endoscope, which is made of metal or partially has a metal layer, and the surface of such a device can conduct electricity.

[0028] The breakdown of charged particles and the oxidation of active oxygen play a major role in killing microorganisms, and can quickly inactivate microorganisms and bacteria on the surface of the sterilized device 5 within 100° C. After sterilization, the working gas 6 is discharged through the exhaust port 4 connected to the sterilization chamber 1.

[0029] Example 2

[0030] Using the above-mentioned atmospheric pressure low-temperature plasma rapid sterilization device, the disinfection method is as follows: contact the sterilized instrument with the power output terminal from the inlet of the sterilized instrument; flush the discharge medium from the air inlet, and open the exhaust port at the same time to replace the air in the sterilization chamber; close the air inlet and outlet; turn on the pulse direct current applied by the pulse power supply, and ground the conductive layer of the sterilization chamber at the same time, discharge in the sterilization chamber to generate plasma; the disinfection time is 5 minutes, the temperature is 95°C; after the sterilization is completed, open the air inlet and outlet valves, use air to flush from the air inlet, and discharge the discharge medium from the air outlet. The disinfected instrument can meet the disinfection requirements of medical instruments such as endoscopes.

[0031] Example 3

[0032] Different from Example 2, the disinfection time is 5 minutes and the temperature is 80° C. The disinfection requirements of medical devices such as endoscopes can be met, and a lower temperature is beneficial to the service life of the endoscope.

[0033] Example 4

[0034] Different from Example 2, the disinfection time is 15 minutes and the temperature is 60° C. The disinfection requirements of medical devices such as endoscopes can be met.

[0035] The above embodiments are the best implementation modes of the present invention, and any equivalent replacements thereof still fall within the protection scope of the present invention.

Claims

1. An atmospheric pressure low temperature plasma rapid sterilization device, comprising a sterilization chamber, an air inlet, an exhaust port, a grounding electrode, an electrode and a pulse power supply, characterized in that: The sterilization chamber has an inlet for instruments to be sterilized, an air inlet and an exhaust port for atmospheric pressure discharge working gas, the sterilization chamber has a conductive layer, the grounding electrode is connected to the conductive layer, the power output end penetrates the sterilization chamber and is insulated from the conductive layer, the power output end is externally connected to a pulse power supply and internally in contact with the instruments to be sterilized, the instruments to be sterilized serve as electrodes, the air inlet and the exhaust port are provided with valves, the sterilization chamber is made of quartz or ceramic material, and the conductive layer is located on the outer layer of the sterilization chamber.

2. The atmospheric pressure low temperature plasma rapid sterilization device according to claim 1, characterized in that: The power output end penetrates into the exhaust port.

3. The atmospheric pressure low temperature plasma rapid sterilization device according to claim 1 or 2, characterized in that: The power output end is made of steel, tungsten metal or their alloys.

4. The atmospheric pressure low temperature plasma rapid sterilization device according to claim 1, characterized in that: The atmospheric pressure discharge working gas is helium or a mixed gas of helium-oxygen-hydrogen peroxide.

5. The atmospheric pressure low temperature plasma rapid sterilization device according to claim 1, characterized in that: The inner end of the power output end is provided with a fixing claw, which is matched and fixed with the instrument to be sterilized.

6. An atmospheric pressure low temperature plasma rapid sterilization method, characterized in that: The atmospheric pressure low-temperature plasma rapid sterilization device according to any one of claims 1 to 5 is used in the following method: contacting the instrument to be sterilized with the output end of the power supply from the inlet of the instrument to be sterilized; rushing in atmospheric pressure discharge working gas from the air inlet, and opening the exhaust port at the same time to replace the air in the sterilization chamber; closing the air inlet and the air outlet; turning on the pulse direct current applied by the pulse power supply, and grounding the conductive layer of the sterilization chamber at the same time, discharging in the sterilization chamber to generate plasma; the disinfection time is 5 to 15 minutes, and the temperature does not exceed 100°C; after the sterilization is completed, opening the air inlet and outlet valves, using air to rush in from the air inlet, and discharging the discharge medium from the air outlet.

7. The atmospheric pressure low temperature plasma rapid sterilization method according to claim 6, characterized in that: The sterilization time is 5 minutes and the temperature is 80°C.

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