CZ33331U1 - Source of low temperature plasma, especially for use in the food industry and bioapplications - Google Patents

Description

Technical field

The technical solution belongs to the field of low-temperature plasma generation and relates to the construction of an atmospheric source of low-temperature plasma especially for use for sterilization of hatching eggs, as well as medical applications.

BACKGROUND OF THE INVENTION

Plasma, as the fourth state of matter, is a state of matter characterized by a certain degree of ionization, and is a mixture of neutral particles, positive and negative ions, the sum of these charges being zero in larger volumes and thus electrically neutral. To maintain a state in the order of 1% of the particles in the ionized state of the plasma, energy corresponding to temperatures of the order of 10 ³ K is required, and such a plasma is referred to as low temperature. Low temperature atmospheric plasma is known as an effective tool for a variety of medical procedures due to the healing effects that can be achieved by its application. This includes antibacterial, antifungal and antiviral effects. It also includes effects associated with chronic wound healing, blood clots, immune system treatment, cardiovascular regulation, destruction of unwanted biofilms, disinfection and sterilization, as known, for example, from CZ 22149 Ul, JP 2001054556, CZ 304814, CZ 306217, CZ 27679 Ul, CZ 31034 U1, US 2012/0046602 A1, WO 2010098524 A1 and CZ 25959 U1.

A number of low temperature atmospheric plasma source technology systems have been developed to date, such as the atmospheric plasma jet apparatus with a set of nozzles for therapy [K. Kim et al., Appl. Phys. Lett. 98 (2011) 073701], a device using low temperature atmospheric plasma for biomedical purposes is described in WO 2010098524 AL Further, an atmospheric plasma source developed for hydrogen atom generation that has a substantial effect on deactivation of microbiological contaminants and reduction of OH radicals in air is available in [H.Nojima et al., J. Phys. C: Appl. Phys. 40 (2007) 501-509], a method for decontaminating air using low temperature plasma is described, for example, in CN 1659968. A self-resonance-based circuit designed for excitation of atmospheric plasma jet and low-volume dielectric barrier discharge has also been developed. v [V. J. Law and S.D. Anghel. J. Phys. C: Appl. Phys. 45 (2012) 075202] and atmospheric plasma excitation based on dielectric barrier discharge technology is also described in CN 101945527. An atmospheric discharge with a DC high-voltage spark generated between the tip and the aperture described for example in [D. Dobrynin, K. Arjunan, A. Fridman, G. Friedman, and A. Morss Clyne. J. Phys. C: Appl. Phys. 44 (2011) 075201], Atmospheric low-temperature, low-temperature, glow-type RF discharge with needle-shaped electrode for deactivating Escherichia coli, which is described in [R.E.J. Sladek and E. Stoffels J. Phys. C: Appl. Phys. 38 (2005) 1716-1721]

Devices using a high frequency (GHz) magnetron volume discharge and using a porous structure to homogenize the ionized working gas stream described, for example, in US 2012/0046602 A1, exhibit negative effects and increased risks to living organisms associated with the use of these frequencies. Another disadvantage of such solutions is its high purchase price. In the solution disclosed in WO 2010098524 A1, a porous structure is used to homogenize the working gas stream, whose ionization occurs only in the microstructure deposited on this material due to the applied high voltage. The disadvantage of this solution is the very low plasma density and its significant area limitation to the maximum diameter in units of millimeters, when the spatial distribution of the plasma density changes significantly as the dimensions increase.

- 1 GB 33331 U1

Many demanding safety criteria must be met to use a plasma source for industrial treatment of biological objects, such as hatching eggs.

In particular, it is the control of plasma dosing, the principles of which are described, for example, in scientific articles [Danil Dobrynin, Gregory Fridman, Gary Friedman and Alexander Fridman, Physical and biological mechanisms of direct plasma interaction with living tissue. Svetlana A. Ermolaeva et al. Bactericidal effects of non-thermal argon plasma in vitro, in biofilms and in animal model of infected wounds Journal of Medical Microbiology (2011), 60, 75-83; Nosenko T., Shimizu T. and Morfill G.E., Designing Plasmas for Chronic Wound Disinfection, New Journal of Physics 11 (2009) 115013 (19pp)].

Part of such requirements are solved, for example, in the construction of CZ 304814 and CZ 23746 U1, which disclose a device for generating a low temperature plasma with a sandwich structure, as well as a tunable concentration of ionized particles. However, the constructions described require very strict production conditions, which can entail high production costs. Also, the lifetime of the excitation electrode can be highly dependent on the quality of the material used.

The aim of the new technical solution is to present an innovated design of a low-temperature plasma source based on the solution according to CZ 304814, while the new design enables to simplify and cheaper production of low-temperature plasma sources, which is a very important aspect of industrial use of low-temperature plasma source in food and bio industry. Also, the improved solution provides a relatively simple construction in terms of mass production. The improved design of the plasma generator, thanks to the special design of the floating potential contact, allows very precise temperature stabilization during plasma generation.

The essence of the technical solution

This object is achieved by a technical solution which is a source of low-temperature plasma, especially for plasma generation for use in medical bioapplications, realized in the form of various volumetric formations and containing a sandwich structure consisting of superimposed grounding electrodes, high temperature resistant non-conductive porous membranes. floating electrodes and excitation electrodes housed in the interior of the hollow body into which the working gas supply is connected. The essence of the technical solution is that between the excitation electrode and the grounding electrode there is a floating electrode made of conductive material, which is electrically isolated from the excitation electrode by a dielectric.

The introduction of another floating potential porous electrode (floating electrode), which is located between the excitation electrode and the ground electrode and is electrically isolated from the excitation electrode by the dielectric, allows non-contact energy transfer between the high potential excitation electrode and the floating electrode using alternating voltage. causes a discharge in the porous dielectric structure between the floating electrode and the grounding electrode. The low resistance of the excitation electrode makes it possible to obtain the same potential over the entire surface of the floating electrode, thereby ensuring a homogeneous concentration and temperature of the generated plasma.

Clarification of drawings

A specific embodiment of the invention is shown in the attached Fig. 1, showing a basic diagram of a low temperature plasma source in vertical axial section.

FIG. 1, which shows the present invention, and the exemplary embodiment described below, in no way limit the scope of protection given in the definition, but merely illustrate the nature of the solution.

-2GB 33331 U1

Examples of technical solutions

In the basic embodiment, the low-temperature plasma source consists of a hollow cylindrical conductive body 1, in the lower part of its interior 101 there is a sandwich structure consisting of layers of porous materials and consisting of superimposed grounding electrode 2, high temperature resistant non-conducting porous membrane 3. and the excitation electrode 5, wherein the body 1 is at the same time the contact of the grounding electrode 2. Into the body 1 an inlet 6 of working gas made of conductive material is connected, which is electrically separated from the body 1 by a tube insulator 7.

Industrial applicability

The technical solution belongs to the area of utilization of low-temperature atmospheric plasma source for the food industry, bio-applications and healthcare. The device is suitable for disinfecting and treating various surfaces such as hatching eggs, skin wounds and the like, while avoiding the risk of tissue damage due to the possible interaction of high electrical alternating voltage.

PROTECTION REQUIREMENTS

Claims (1)

A source of low temperature plasma, in particular for plasma generation for use in medical bioapplications, in the form of various volumetric formations and comprising a sandwich structure consisting of superimposed grounding electrodes (2), high temperature resistant non-conductive porous membranes (3), floating electrodes (4) and excitation electrodes (5) housed in the interior space (101) of the hollow body (1) into which the working gas supply (6) extends, characterized in that between the excitation electrode (5) and the grounding electrode (2) 1) a floating electrode (4) made of a conductive material is electrically isolated from the excitation electrode (5) by a dielectric.