JP2005305060A - Method and device for sterilization with electromagnetic wave - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for sterilizing bacteria, etc., with the use of a terahertz generator, and to provide its device. <P>SOLUTION: The device irradiates the arbitrary place of an object 2 to be measured and operated with a frequency variable terahertz wave 5, detects a reflection terahertz wave 4, obtains terahertz spectrum, and detects the existence of bacteria, etc., concerning the terahertz wave generator. Through the use of the method and device, the spectrum is analyzed, so as to select an optimum terahertz wave frequency and sterilization is performed by irradiating the object to be measured and operated with the selected terahertz wave. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to microorganism detection and selective sterilization, sterilization methods and devices.

  Hygiene management for preventing infectious diseases such as infectious diseases is not limited to the medical field, and attention is paid widely to the general public. For example, gargle and hand-washing practices for cold prevention etc. are some of them. Strict hygiene management is applied especially in the field of food processing. For example, products are so-called sterilized through treatments such as heating, disinfection, pressurization, and energization.

  All of these are for removing microorganisms such as viruses, bacteria, and fungi that cause infections and food poisoning. For example, in order to sterilize mineral water, heat sterilization, filter sterilization, ozone sterilization, ultraviolet sterilization, etc. are generally performed, and chlorination is used for tap water. In sterilization of milk with high nutritional value and easy bacterial growth, low temperature maintenance sterilization method (Low Temperature Long Time Pasteurization, LTLT method), heating at 62-65 ° C for 30 minutes or more, 72 ° C for 15 seconds or more High temperature short time sterilization method (High Temperature Short method, HTST method), ultra high temperature heat treatment method (Ultra High Temperature Heating method, UHT method) in which heating is performed at 120 to 150 ° C. for 1 to 3 seconds or more is used. The same heat sterilization is also used for fruit juices and alcoholic beverages.

  An organic polymer or the like constituting a living body has an interatomic bond in a molecule or a natural vibration frequency of an intermolecular bond in a terahertz frequency band. By sweeping the frequency and irradiating the target with terahertz waves and detecting the reflected or transmitted waves, the presence and type of microorganisms can be identified from the absorption characteristics.

  If this natural vibration frequency terahertz wave is irradiated from the outside as coherent light, only the coupling can be selectively excited. If this terahertz wave is increased in intensity, the coupling will eventually be broken by excess energy. This process means that energy can be selectively applied only to the intended bond in the intended molecule to change the molecular structure or destroy the molecular structure.

  Microorganisms such as viruses and bacteria are invisible, and there are limits to how they can be handled with human attention. In addition, sterilization methods such as heating, pressurization, and energization performed in the food processing field decompose not only bacteria but also nutritional components such as vitamins and flavor and flavor components, resulting in quality degradation. Chemical sterilization methods using chemicals such as disinfectants are sterilized by coagulation of proteins, oxidation of bacterial cell components, formation of heavy metal salts, etc., but there is concern about the effects of chemicals remaining in food.

  As a sterilization method for irradiating electromagnetic waves, there is a heating method using microwaves. This is because water molecules contained in an object to be sterilized absorb the electromagnetic wave and heat it, and it can be said that the entire object is heated. On the other hand, in the method of irradiating terahertz waves of the present invention, it is possible to selectively heat and sterilize, for example, only bacteria in the object, not the entire object.

  The terahertz wave generator can provide a coherent terahertz wave having an arbitrary frequency with high output.

  For microorganisms such as viruses, bacteria (bacteria), and fungi with a small living body and a small number of constituent molecules, the presence and type of microorganisms can be identified from the frequency dependence of terahertz wave absorption.

  In addition, if a target is irradiated with a terahertz wave with a high frequency (resonance frequency) that is absorbed only by a specific microorganism with high energy, the heat is selectively transmitted to the microorganism without affecting other parts. And the microorganisms die because they are locally heated.

  That is, according to the present invention, the terahertz wave generated by the terahertz wave generator locally raises the temperature of microorganisms such as pathogen viruses, bacteria (bacteria), and fungi, and kills them without affecting normal parts. Can do.

  This means that hygiene evaluation and purification can be performed in a variety of environments, from environments that are essentially sterile, such as operating rooms and semiconductor factories at medical sites, to relatively inferior sanitary environments, such as outdoors and public institutions with high traffic. it can.

  Particularly in the field of food processing, it is possible to provide a sterilized processed food without impairing nutrition, flavor and flavor.

  In the fishery sector, harmful plankton that causes red tide, for example, can be selectively killed without affecting the effective plankton that feeds fish.

  In the medical field, fungal-derived diseases can be treated without affecting normal tissues.

  As a terahertz generator, there is a difference frequency generator using a phonon polariton mode in a GaP crystal. This can generate a coherent terahertz wave of any frequency with high output and high resolution.

  Terahertz spectrum measurement is effective for detecting remaining bacteria and viruses in aseptic rooms such as hospital operating rooms and semiconductor factory clean rooms. As shown in FIG. 1 (a), the terahertz generator 1 is used to irradiate the measurement and action target 3 while sweeping the frequency of the generated terahertz wave 2. The measurement and action target 3 is a wall, floor, ceiling, or space containing microorganisms. By detecting the reflected terahertz wave 4 or the transmitted terahertz wave using a terahertz detector 5 such as a bolometer or DTGS, the frequency dependence of the absorption characteristic, that is, the terahertz absorption spectrum diagram 1 (c) is obtained. From this spectrum, the presence of microorganisms such as bacteria and viruses can be confirmed and identified. An object such as a microorganism does not necessarily need to be identified, but a terahertz frequency that is specifically absorbed by the microorganism, that is, a resonance frequency is obtained.

  If the terahertz wave is a frequency that is difficult to be absorbed by the surrounding materials, the generated terahertz wave 6 having the optimum frequency obtained by the above procedure is measured and measured using the terahertz generator 1 as shown in FIG. When the action object 3 is irradiated with, for example, 100 mW, it is selectively absorbed only by the microorganisms, so that the microorganisms can be killed by being locally heated. That is, selective sterilization becomes possible.

  Alternatively, after the sterilization treatment, the sterilization effect can be confirmed by observing the terahertz absorption spectrum diagram 1 (c) again with the means of FIG. 1 (a).

  Of course, the same microorganism detection and sterilization process can be performed not only in an aseptic room, but also in a normal room, space, or outdoors, and can be applied to purification of living bodies such as purification of spaces and objects or hand washing.

  Diseases caused by microorganisms range from common diseases such as colds and food poisoning to intractable diseases such as cholera and AIDS. Examples of microorganisms that cause disease include influenza virus, Japanese encephalitis virus, herpes virus, coronavirus, HIV virus, and Ebola virus. Bacteria include Escherichia coli, Salmonella, Vibrio cholerae, Bordetella pertussis, Mycobacterium tuberculosis, Staphylococcus aureus, Helicobacter pylori, and fungi include ringworm, Candida, and Aspergillus.

  For example, in order to treat skin disease athlete's foot and insect beetle, it is effective to sterilize the causative fungus that is the causative bacterium. Conventional treatment is generally performed by applying a drug. However, if a terahertz wave 6 having an optimum frequency is irradiated to a human body part 10 such as skin using the terahertz generator 1 as shown in FIG. Only works effectively and can directly destroy pathogenic bacteria.

  Foods with high nutritional value, such as rice and bread, are easy for bacteria and fungi to grow and become pathogenic bacteria such as food poisoning. Terahertz spectrum measurement and imaging measurement are effective for detecting fungi such as mold. For example, when there are three types of molds A, B, and C that may occur, the respective spectra are as shown in FIG. That is, the fungus A has a large absorption at the frequency a and does not absorb at the frequencies b and c. Similarly, absorption of terahertz waves is observed at the frequency of b in the bacterium B and at the frequency of c in the bacterium C. When viewing such an object, if the generated terahertz wave is fixed at a frequency, the irradiation direction of the generated terahertz wave is spatially swept, and the reflected terahertz wave or the transmitted terahertz wave is detected, the terahertz intensity at each location From the difference, a terahertz imaging image at a specific frequency is obtained. Bacteria A will be detected if detected at the frequency a, B will be detected if detected at the frequency b, and B will be detected if detected at the frequency c, and the spatial distribution of each will also be obtained.

  If the terahertz wave 6 of the optimal frequency which the detected microbe absorbs is irradiated to the sterilization targets 21 such as food using the terahertz generator 1 as shown in FIG. 3B, only each microbe is selectively sterilized. be able to. Here, in order to irradiate a terahertz wave over a large area in order to speed up the sterilization treatment, the terahertz beam may be diffused using a concave lens 20 made of polyethylene or the like.

  Liquid foods containing beverages such as fruit juices, milk, and alcoholic beverages often have a high nutritional value such as containing a large amount of sugars, so that bacteria are easy to propagate, and sterilization is very important. However, in normal heat treatment, for example, nutrient components such as vitamins and carotene in fruit juice drinks are decomposed. Similarly, in other liquid foods, nutritional components are decomposed, and flavor components and flavor components are also decomposed. In particular, if alcoholic beverages can be sterilized without heating, so-called fresh sake that does not lose its flavor can be easily distributed. As shown in FIG. 4, in the fluid path 32 between the first tank 30 and the second tank 31 by the pump 33, resonance of specific bacteria such as Escherichia coli and lactic acid bacteria collectively called so-called rot bacteria. If the terahertz wave 6 is irradiated using the terahertz wave generator 1 having a frequency that does not affect the fungi, nutritional components, flavor components, and flavor components necessary for aging such as yeast, the quality can be obtained. It can be sterilized while avoiding deterioration. At this time, the sterilization is not sufficient unless the terahertz wave is sufficiently transmitted through the object. For this reason, the rectifying device 34 is provided, and the flow rate may be adjusted while reducing the target fluid to about 100 μm. The polyethylene concave lens 20 enlarges the generated terahertz wave 6 in order to speed up the sterilization treatment.

  Water purification is important in the breeding and aquaculture of aquatic organisms such as fish. Water pollution may be due to chemical contamination or abnormal bacterial growth. For example, red tides mainly cause marine phytoplankton such as diatoms, dinoflagellates, and raffido algae to grow, and substances (unsaturated fatty acids, active oxygen, etc.) produced by plankton paralyze the functions of fish gills. It is said to cause damage to living organisms.

  As shown in FIG. 5, when water 41 is circulated through a flow path 42 using a pump 43 in a water tank 40 such as an aquarium, a terahertz wave that becomes a resonance frequency for a specific harmful plankton is generated using the terahertz generator 1. If 6 is irradiated to circulating water, only harmful plankton can be selectively removed, for example, it does not affect plankton that serves as fish food. In order to make the sterilization effect effective, a rectifying device 44 is provided to make the water 41 as thin as about 100 μm and adjust the flow rate. In addition, the polyethylene concave lens 20 enlarges the generated terahertz wave 6 in order to speed up the sterilization process.

  It can be used to purify water in ornamental aquariums and live fish tanks, and to prevent and treat red tides in aquaculture.

  (A) Detection of bacteria by reflected terahertz wave, (b) Sterilization by terahertz wave irradiation, (c) Terahertz absorption spectrum by bacteria.   It is a figure which shows disinfection of the pathogenic microbe by terahertz wave irradiation.   (A) Terahertz absorption spectrum by three types of molds A, B, and C, (b) A diagram showing sterilization of food by terahertz wave irradiation.   It is a figure which shows disinfection of the liquid food by terahertz wave irradiation.   It is a figure which shows disinfection of the water in the water tank by terahertz wave irradiation.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Terahertz wave generator 2 ... Generated terahertz wave 3 ... Measurement and action object 4 ... Reflected terahertz wave 5 ... Terahertz detector 6 ... Generated terahertz wave with optimal frequency 10 ... Human body part 11 ... Affected tissue 20 ... Polyethylene concave lens 21 ... sterilization target 30 ... first tank 31 ... second tank 32 ... fluid path 33 ... pump 34 ... rectifier 40 ... water tank 41 ... water 42 ... flow path 43 ... pump 44 ... rectifier

Claims (3)

  The present invention relates to a sterilization apparatus using terahertz waves, and has a function of irradiating at least one or more arbitrary single frequencies with a specified terahertz wave, which can limit the range, And apparatus for selectively sterilizing or sterilizing bacteria in a cell by selecting a frequency.   The sterilizer using the terahertz wave according to claim 1, wherein a function of detecting bacteria at each position from the position and frequency spectrum information of the target object by measuring at least the reflected terahertz wave in the target object. And measuring the effect of sterilization or sterilization.   The sterilizer using the terahertz wave according to claim 1, wherein a function of detecting bacteria at each position from the position and frequency spectrum information of the target object by measuring at least the reflected terahertz wave in the target object. And a position where the terahertz wave is irradiated can be selected in advance.

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