Cold atmospheric plasma treatment device
The device uses a dielectric barrier discharge system to propagate cold atmospheric plasma and air flow for targeted treatment of cancerous tumors, addressing the challenge of delivering plasma to internal targets while minimizing tissue damage.
Patent Information
- Authority / Receiving Office
- FR · FR
- Patent Type
- Applications
- Current Assignee / Owner
- UNIVERSITE CLERMONT AUVERGNE
- Filing Date
- 2024-12-02
- Publication Date
- 2026-06-05
AI Technical Summary
There is a need to deliver cold atmospheric plasma effectively to a cancerous tumor located inside a patient's body, as existing methods struggle to penetrate and treat targets within an environment without damaging surrounding tissues.
A device with an ionization chamber and dielectric barrier discharge system generates cold atmospheric plasma, using a dielectric barrier discharge to propagate high-voltage current along an elongated body to a distribution head, which ionizes a plasmagenic gas and air flow, producing reactive oxygen and nitrogen species (RONS) for targeted treatment.
Enables the generation and delivery of cold atmospheric plasma with RONS to treat cancerous tumors within a patient's body, avoiding damage to surrounding tissues by maintaining plasma ionization and airflow through the elongated body, enhancing treatment efficacy.
Abstract
Description
Title of the invention: Cold atmospheric plasma treatment device
[0001] The invention relates to the field of cold atmospheric plasma treatment devices, in particular cold atmospheric plasma treatment devices for cancerous tumors.
[0002] Plasma is the fourth state of matter (solid, liquid, gas and plasma) which represents more than 99% of the visible universe and corresponds to an ionized gas composed of positively / negatively charged species, neutral species, radicals and photons.
[0003] Plasma medicine has become a new scientific field following intense research efforts on the applications of low-temperature or cold atmospheric plasmas. Cold plasma at atmospheric pressure is distinguished by its composition: a gas weakly ionized by electrons from the current supplied by a high-voltage power source. Unlike thermal plasma, where electrons and heavy particles are in thermal equilibrium, cold plasma is characterized by a thermal imbalance; the electrons are hot (10 to 20 kilokelvins) and the heavy particles (atoms, molecules, ions) are cold. Indeed, at atmospheric pressure, the temperature of heavy particles in cold plasma varies between 300 and 500 Kelvin (25°C to 50°C), thus allowing treatments on organisms without significantly damaging the structure of the targeted surface.
[0004] It is known that cold atmospheric plasmas in contact with air produce various chemically reactive species, including reactive oxygen species (ROS) and reactive nitrogen species (RNS). Cold plasma is a cocktail containing ROS and RNS, also called RONS, in combination with transient electric fields, UV radiation, and charged species.
[0005] Cold plasma generation devices are very promising in the fields of biomedicine, the environment, agriculture, food, catalysis, surface modification, etc.
[0006] It is known from the document Kajiyama et al, Possible therapeutic option of aqueous plasma for refractory ovarian cancer, Clin. Plasma Med. 4 (2016), that cold plasma is effective in treating cancer cells, either by direct treatment by applying the plasma to the surface of the cancer cells, or by indirect treatment by pretreating a cell culture medium with plasma and then incubating the cells with this activated medium. This effectiveness results in particular from the increase in intracellular oxygenated reagents causing DNA damage and mitochondrial damage leading to cell apoptosis.
[0007] Nevertheless, there is still a need to enable the delivery of plasma to a cancerous tumor located inside a patient's body.
[0008] To this end, the invention relates to a device for treating a target with cold atmospheric plasma comprising an ionization chamber for a plasma-generating gas including a dielectric barrier discharge, where the ionization chamber comprises • an elongated body, and • a distribution head,
[0009] where the dielectric barrier discharge is configured on the one hand to apply a high voltage current to the plasma gas flow in order to obtain a cold atmospheric plasma flow formed of ionized plasma gas and on the other hand to propagate a high voltage current along the elongated body up to the distribution head in order to maintain the ionization of the plasma gas in the elongated body up to the distribution head,
[0010] where the elongated body is configured to carry the flow of plasmagenic gas as well as to carry the flow of cold atmospheric plasma formed from ionized plasmagenic gas and an air flow to the distribution head, and
[0011] where the distribution head is configured to generate a cold atmospheric plasma comprising oxygenated and nitrogenated reagents by ionization of the air stream by the cold atmospheric plasma stream formed from ionized plasmagenic gas.
[0012] The invention advantageously allows the generation of a cold atmospheric plasma containing oxygenated and nitrogenous reagents (RONS) in contact with, or even within, a target. The absence of air at the target in an environment, and moreover the absence of air inside the target itself, preventing the formation of RONS and therefore the treatment of the target, is advantageously compensated in the invention by the transport of an airflow through the elongated body flowing into the cold atmospheric plasma of ionized plasmagenic gas. The plasmagenic gas is ionized upstream (cold atmospheric plasma of plasmagenic gas) and transported in this state by means of the propagation of high-voltage current through the dielectric discharge barrier. The ionized plasmagenic gas serves as a vector for the remote ionization of the airflow at the target.
[0013] In this description, the terms “atmospheric pressure cold plasma”, “cold atmospheric plasma” and “cold plasma” shall be taken as synonyms.
[0014] According to one embodiment of the invention, the elongated body comprises a first transport conduit configured to transport the flow of plasmagenic gas and the flow of cold atmospheric plasma formed from ionized plasmagenic gas, as well as a second A transport duct configured to carry the airflow, wherein the second transport duct is disposed within all or part of the first transport duct. This aspect of the invention simplifies the device and facilitates the insertion of the elongated body into the environment up to the target.
[0015] According to one embodiment of the invention, the elongated body includes a third transport conduit configured to recover exhaust gases from the distribution head.
[0016] According to one embodiment of the invention, the dielectric discharge barrier comprises a propagation element for the propagation of the high voltage. Preferably, the propagation element is in the form of a metallic guide.
[0017] According to one embodiment of the invention, the distribution head comprises a first cold atmospheric plasma flow distribution tube formed of ionized plasmagenic gas and a second air flow distribution tube, where one of the two tubes is electrically connected to the electric discharge barrier, preferably one of the two tubes is electrically connected to the propagation element.
[0018] In particular, the second distribution tube is arranged inside the first distribution tube. Furthermore, the distal end of the second distribution tube is located upstream of the distal end of the first distribution tube. These configurations allow for a first outlet of air surrounded by ionized plasma gas, resulting in improved ionization of the air and thus improved production of RONS compounds.
[0019] According to one embodiment of the invention, the distribution head includes a perforation element configured on the one hand to penetrate the target and on the other hand to create a distribution space for the cold atmospheric plasma comprising oxygenated and nitrogenous reagents.
[0020] In particular, the perforation element is mounted on the first distribution tube.
[0021] The invention also relates to a method for in vitro or ex vivo treatment of one or more cancerous tumor cells, said method comprising a step of inserting the delivery head of the treatment device as defined above into said at least one cancerous tumor cell, and a step of generating a cold atmospheric plasma comprising oxygenated and nitrogenous reagents from a plasmagenic gas stream, an air stream and a high electrical voltage.
[0022] The invention also relates to a method for the therapeutic treatment of a cancerous tumor in a patient, said method comprising a step of inserting the delivery head into the patient's body up to said cancerous tumor, and a step of generating a cold atmospheric plasma comprising oxygenated and nitrogenous reagents from a plasma-generating gas stream, an air stream, and a high voltage electrical. The said cancerous tumor is notably located within the patient's body. Brief description of the figures
[0023] The invention will be better understood in the light of the following description, which is purely illustrative and not limiting, and is made with reference to the accompanying drawings in which:
[0024] Fig. 1 represents a general view of a cold atmospheric plasma treatment device according to the invention.
[0025] Fig. 2 is a detail view of the circled part I of Fig. 1 showing in cross-section the proximal part of an elongated body of the treatment device.
[0026] Fig. 3 is a detail view of the circled part II of Fig. 1 showing in cross-section a fitting of an elongated body of the processing device.
[0027] Fig. 4 is a detail view of circled part III of Fig. 1 showing a cross-sectional view of a distribution head of the operating treatment device generating a cold plasma. Detailed description
[0028] In this description the terms "upstream" and "downstream" as well as the terms "proximal" and "distal" shall be understood according to the direction of flow of the plasma-generating gas in the treatment device of the invention.
[0029] According to a first object, the invention relates to a cold atmospheric plasma treatment device 1, as shown in [Fig. 1]. The treatment device 1 comprises an ionization chamber 10 including a dielectric barrier discharge 100 (visible in [Fig. 2]), an elongated body 200 and a distribution head 300.
[0030] The ionization chamber 10 is configured to generate a cold plasma comprising RONS 2 at a target 3, itself located within an environment 4. The target 3 is, in particular, organic matter, and more specifically one or more cancerous tumor cells, in particular those constituting a cancerous tumor. The environment 4 is, in particular, a human or animal body.
[0031] To this end, the ionization chamber 10 includes, in particular: - a first inlet 21 for receiving a flow of plasma-generating gas, - a second inlet 22 for receiving an airflow, - a set of conduits 51, 52 for transporting the flow of plasmagenic gas, a cold plasma of gas formed from ionized plasmagen and the flow of air and - a first output 31 of distribution of a cold plasma including RONS 2 at the level of the target 3.
[0032] The plasma-generating gas used in the invention can be any known plasma-generating gas, and in particular a noble gas such as helium or argon, or a mixture of these.
[0033] According to one embodiment of the invention, the first inlet 21 is adapted to be connected to a plasma-generating gas supply source 5. According to one embodiment, the device 1 may include a supply source 5 connected to the proximal end of the elongated body 200 or connected to said proximal end via a first inlet transport conduit 41, as shown in [Fig.2].
[0034] The airflow is transported to the target 3. This aspect of the invention allows for the presence of air at the cold plasma formation site and therefore the generation of RONs at the target 3. Indeed, when the delivery head is in contact with, or even penetrates, the target 3, no surrounding air is available to form RONs. In this context, this aspect of the invention thus makes it possible to obtain RON formation, even if the target 3 is buried in the environment 4, as is the case with a cancerous tumor in a body, and therefore to treat said target 3.
[0035] Similar to the first inlet 21, the second inlet 22 is adapted to be connected to an air pump 6. According to one embodiment, the treatment device 1 comprises an air pump 6 connected either directly to the second inlet 22 of the elongated body 200 or via a second inlet transport conduit 42, as shown in [Fig. 3]. This air pump 6 may be any pump that provides a constant flow rate, and in particular a pneumatic diaphragm pump, a diaphragm pump, a piston pump, a centrifugal pump, a bellows pump, an electromagnetic pump, or a peristaltic pump.
[0036] The dielectric discharge barrier 100 is configured to apply a high-voltage current to the plasma-generating gas at a specific area of the elongated body 200. As such, the dielectric discharge barrier may include any system configured to apply a high-voltage current to a plasma-generating gas, and in particular a dielectric discharge barrier for a plasma gun or a dielectric discharge barrier for a Tesla plasma jet. For this purpose, the dielectric discharge barrier 100 includes, in particular, a voltage electrode 110 and a ground electrode 111, as in the example shown in [Fig. 2]. Naturally, the configuration (shape and arrangement) of the electrodes 110, 111 is adapted to the type of dielectric discharge barrier used, some of which will be described in detail later.
[0037] Applying high-voltage current to the plasma-generating gas ionizes it. This results in a cold plasma formed from ionized plasma-generating gas.
[0038] In the invention, "high voltage" means a voltage greater than 5 kV, and in particular between 7 and 10 kV. This high voltage enables ionization of the plasma gas when it passes through it.
[0039] The dielectric barrier discharge 100 comprises a set of electrically conductive wires 112 connected respectively to each electrode 110, 111. According to one embodiment of the invention, the set of conductive wires 112 can be fixed to electrical connectors intended to be connected to a high-voltage power supply 7. Alternatively, the treatment device 1 may comprise said high-voltage power supply 7.
[0040] As can be seen in [Fig.2], the electrodes 110, 111 are preferentially arranged at the upstream part of the elongated body 200, for example near the first inlet 21. Due to this configuration, bulky elements and branches do not hinder the movement of the distribution head 300 and the elongated body 200 in the environment 4 to reach the target 3. This movement is thus mainly limited only by the size of the elongated body 200.
[0041] The dielectric barrier discharge 100 is also configured to propagate the high-voltage current along the elongated body 200 to the distribution head 300. Indeed, without this propagation, the cold plasma of ionized plasmagen gas would remain close to the electrodes 110, 111. Thus, unlike a standard dielectric barrier discharge construction, the cold plasma 2 does not remain at the electrodes 110, 111 but is propagated to the distribution head 300. This configuration makes it possible to maintain the ionization of the plasmagen gas along the elongated body 200 and therefore to transport an ionization vector from the airflow close to the target 3, so that the RONS generated by contact between the cold plasma of ionized plasmagen gas and the airflow can properly treat the target 3. For this purpose, the dielectric barrier discharge may include a propagation element 113, described in detail later.
[0042] The elongated body 200 is configured to transport the plasmagenic gas flow, the cold plasma of ionized plasmagenic gas and the air flow to the distribution head 300. For this purpose, the elongated body 200 includes in particular the first and second inlets 21, 22 and the set of conduits 51, 52.
[0043] According to one embodiment of the invention, the elongated body 200 comprises a first transport conduit 51 for the plasma-generating gas and the cold plasma flow of ionized gas, the first transport conduit 51 being provided with the first inlet 21. Said first transport conduit 51 is in particular made of one or more dielectric materials. The dielectric material(s) are in particular selected from the group consisting of quartz, Pyrex, silicone, polyurethane, or polytetrafluoroethylene. The dielectric material(s) are in particular biocompatible, especially for application in a human or animal body.
[0044] The dielectric discharge barrier 100 is in particular configured to apply a high-voltage current to a zone of the first transport conduit 51. For this purpose, the electrodes 110, 111 are each arranged independently of each other outside, inside, or in the walls of the first transport conduit 51. As shown in [Fig. 2], the electrodes 110, 111 may be toroidal in shape and arranged one downstream of the other. Any order of electrodes 110, 111 can be used but it is preferable that the ground electrode 111 be disposed downstream in order to limit the output voltage at the distribution head 300. Alternatively, the electrodes 110, 111 are wound in a helix and at an equal distance from each other.When one or more electrodes 110, 111 are arranged outside the first transport conduit 51, they are in particular arranged in a chamber 60, as shown in [Fig.2], through which the first transport conduit 51 passes.
[0045] According to one embodiment of the invention, the dielectric discharge barrier 100 is also configured to propagate the high voltage current, outside, inside or in the walls of the first transport conduit 51 by means of the propagation member 113.
[0046] When the dielectric discharge barrier 100 is configured to propagate the high voltage current outside the first transport conduit 51, the latter is in particular disposed in an insulating protective sheath, in order to prevent the current from propagating to the environment 4 and damaging it.
[0047] The propagation element 113 is notably in the form of a metallic guide, as in the example shown in [Fig. 2]. When the electrodes 100, 111 have a toroidal shape, the metallic guide 113 is positioned opposite all or part of the downstream electrode 110, 111. Said metallic guide 112 may be made of any conductive metal configured to withstand a high-voltage current, and is notably made of copper. The metallic guide 113 is notably not in contact with the electrodes 110, 111, as shown in [Fig. 2].
[0048] The propagation element 113 may also correspond to a direct extension of the electrodes 110, 111, particularly when the latter have a helical shape. Thus, the electrodes 110, 111 are wound along the first transport conduit 51 to the distribution head 300.
[0049] The first transport conduit 51 may comprise one or more sections 511, 512 along the elongated body 200. When several sections are present, they may each be made of a different material or of the same material, adapted in particular according to the use of the section. For example, a connected section the distribution head 300 will preferably be made of a flexible material, and a section opposite the electrodes 110, 111 will preferably be rigid.
[0050] The first transport conduit 51 includes, in particular, a first upstream section 511 comprising the area where the electrodes 110, 111 apply the high-voltage current, and where the ionization of the plasma gas takes place. The first section 511 thus includes an inlet flow of plasma gas and an outlet flow of cold plasma of ionized plasma gas. An example of this first section 511 is shown in [Fig. 2]. This first section 511 is made of a rigid insulating material, such as quartz. In particular, this section 511 is not intended to be in contact with the environment 4.
[0051] The first transport conduit 51 may also include at least one second section 512. The second section 512, or the upstream second section 512, is connected or made of material with the first section; preferably, it is connected. The second section(s) have, in particular, a different diameter 512 than the first section 511, especially a smaller diameter as shown in [Fig. 2]. The diameter of each second section 512 may also be different, as will be seen in detail later. The second section 512, or the downstream second section 512, is connected with the distribution head 300. The second section(s) 512, or at least a portion thereof, are intended to be in contact with the environment 4. For this purpose, they are preferably made of a flexible material, in particular a biocompatible one, to facilitate the movement of the distribution head 300 in the environment 4.
[0052] The elongated body 100 further comprises, in particular, a second transport conduit 52 configured to carry the airflow. The second transport conduit 52 is made of a flexible material, in particular selected from the group consisting of silicone, polyurethane, or polytetrafluoroethylene. The upstream end of the second transport conduit 52 thus comprises the second inlet 22.
[0053] Along at least one part of the elongated body 200, the first and second transport conduits 51, 52 may be side by side or one may be contained within all or part of the other. In particular, the second transport conduit 52 is disposed within a part of the first transport conduit 51, notably in one or more second sections 512. The first and second transport conduits 51, 52 join, in particular, after the area of application of the high-voltage current by the electrodes 110, 111. In particular, the second transport conduit joins the first transport conduit 51 after the first section 511 of the first transport conduit 51, as shown in [Fig. 3].
[0054] Like the first transport conduit 51, the second transport conduit can comprise several sections 521 of identical or different material and diameter.
[0055] The elongated body 200 may also include a third transport conduit 53 allowing the escape of gases from the source 3 following the generation of the cold plasma 2. The presence of the third transport conduit 53 makes it possible, in particular, to avoid swelling at the target 3 due to the supply of gas (plasmagen and air) to form the cold plasma and the RONS, which could alter the environment 4, and in particular damage healthy cells present next to a targeted cancerous tumor 3. The third transport conduit 53 thus includes a second outlet 32 for the release of gases. The third outlet 32 leads, in particular, directly, or indirectly via a first outlet conduit, into a treatment system 8, as shown in [Fig. 1].According to one embodiment of the invention, the third transport conduit 53 includes a bypass connected to the first conduit 51, in order to obtain recirculation in the first conduit 51 of at least a part of the exhaust gas flow (comprising ionized chemical elements), and thus to enhance the presence of RONS in the cold plasma.
[0056] Like the second transport conduit 52, the third transport conduit 53 is made of a flexible material, in particular chosen from the group consisting of silicone, polyurethane, or polytetrafluoroethylene. The third transport conduit 53 may run alongside the second and / or first transport conduit 51, 52, or may be disposed in all or part of the first or second transport conduit 51, 52. The third conduit 53 separates from the first transport conduit 51 downstream of the area where the high-voltage current is applied by the electrodes 110, 111. In particular, the third conduit 53 separates from the first transport conduit 51 downstream of the first section 511 of the first transport conduit 51. The third transport conduit 53 may, in particular, comprise several sections of identical or different materials and diameters.
[0057] Each conduit 51, 52, 53, or each section of conduit 51, 52, 53, may have a diameter of 0.2 to 10 mm, in particular 0.4 to 5 mm. When conduits 51, 52 and / or 53 are side by side, they are in particular arranged in a sheath. This sheath is in particular flexible and preferably made of a biocompatible material, like conduits 52 and 53.
[0058] The elongated body 200 includes, in particular, one or more fittings 210, as shown in [Fig. 3]. This fitting or these fittings 210 allow, in particular, the connections of the different sections of the conduits 51, 52, 53, as well as the joining or separation of these conduits 51, 52, 53, as can be seen in [Fig. 3]. Also visible in [Fig. 3] is a second section 512 of the first transport conduit 51, inside which run the second transport conduit 52, the third transport conduit 53, and a metal guide 113.
[0059] Following their transport by the elongated body 200, the distribution head 300 enables the formation of a cold plasma comprising RONS 2 by ionizing the airflow with the cold plasma of ionized plasmagenic gas. An example of an embodiment is shown in [Fig. 4]. The distribution head includes the first outlet 31. The distribution head has, in particular, an elongated shape to improve its penetration into the environment 4 up to the target 3.
[0060] To this end, the distribution head 300 includes, in particular, a first distribution tube 311 for the cold plasma flow of ionized plasmagenic gas and a second distribution tube 312 for the air flow. The first and / or second tube 311, 312 may each independently originate from the material with the corresponding first and / or second transport conduit 51, 52 or be connected to it. This connection may also be indirect, as shown in [Fig. 4]. In this example, the first and second transport conduits 51, 52 open into a housing 330 of the distribution head 300 into which the first and second tubes 311, 312 are inserted opposite each other. The propagation element 113 may also be disposed in said housing 330.
[0061] According to one embodiment of the invention, one of the two distribution tubes 311, 312 is electrically connected to the propagation element 113 of the dielectric discharge barrier 100. In particular, the second tube 312 is the connected tube, as shown in [Fig. 4]. This electrical connection can be made by any means, and includes in particular the presence of a metallic layer disposed on the inner wall, in the wall, or on the outer wall of the connected distribution tube 311, 312, or by the metallic composition of the connected distribution tube 311, 312. The connecting element 113 may, in particular, include a distal end attached to the connected tube 311, 312, as shown, for example, by means of coils and / or by welding.
[0062] The cold plasma stream of ionized plasmagenic gas is transported to the downstream end of the connected distribution tube 311, 312. The RONS are formed by ionization of the air stream by the cold plasma stream of ionized plasmagenic gas, as shown.
[0063] In particular, the first and / or second tube 311, 312 may be in the form of a metallic needle. This aspect of the invention also allows penetration of the first and / or second tube 311, 312 into the target 3.
[0064] The first and second distribution tubes 311, 312 can be arranged side by side or one inside the other. In particular, the second tube 312 is arranged inside the first tube 311. Thus, the distributed airflow is surrounded by the cold plasma, thereby increasing the amount of RONS produced, and thus the effectiveness of the treatment.
[0065] The distal ends of the first and second tubes 311, 312 may be at the same height, or one may be further downstream than the other. In particular, the distal end of the second tube 312 may be upstream of the distal end of the first tube 311.
[0066] According to one embodiment of the invention, the distribution head 300 may also include a third recovery tube 313 for recovering gases following the formation of the cold plasma comprising the RONS 2, said third tube 313 being connected or formed from material with the third transport conduit 53 of the elongated body 200. The distal end of the third tube 313 is, in particular, disposed upstream of the distal ends of the first and second tubes 311, 312, as shown, in order to recover the rising gases. The third tube 313 may be inserted into the distal end of the chamber 330, like the tubes 311 and 312, or run along the chamber 330 to the upstream portion and connect with the third transport conduit 53.
[0067] According to one embodiment of the invention, the distribution head 300 may include a perforation element 320, in which the distal end of the distribution tubes 311, 312 is disposed, as shown in [Fig. 4]. The perforation element 320 is configured, on the one hand, to penetrate the target 3 and, on the other hand, to create a distribution space for the cold plasma provided with the RONS 2. Thus, the perforation element 320 may include a housing 321 open towards the target 3 into which the first, second, and third tubes 311, 312, 313 open. The perforation element is made, in particular, of a rigid and preferably dielectric material, in order to avoid disturbance of the plasma. It is, in particular, made of quartz. The height of the perforation element 320 is configured, in particular, to be less than the height of the cold plasma 2 delivered at the distribution head.
[0068] The perforation member is mounted in particular on the first or second of the distribution tube 311, 312. Preferably, the perforation member is mounted on the first distribution tube 311, as shown in [Fig.4].
[0069] The invention also relates to a method for treating a target 3, comprising a step of inserting the distribution head 300 into the target 3, and a step of generating a cold plasma comprising oxygenated and nitrogenated reagents 2 at said distribution head 300 from a plasma-generating gas stream, an air stream, and a high electrical voltage. The target 3 is, in particular, embedded within an environment 4.
[0070] The invention also relates to a method for in vitro or ex vivo treatment of one or more cancerous tumor cells 3, said method comprising a step of inserting the delivery head 300 into said cancerous tumor cells 3, and a step of generating a cold atmospheric plasma comprising reagents oxygenated and nitrogenous 2 from a plasma gas stream, an air stream and a high electrical voltage.
[0071] The invention further relates to a method for the therapeutic treatment of a cancerous tumor 3 in a patient, said method comprising a step of inserting the delivery head 300 into the patient's body 4 up to said cancerous tumor 3, and a step of generating a cold atmospheric plasma comprising oxygenated and nitrogenous reagents 2 from a plasma-generating gas stream, an air stream, and a high electrical voltage. The cancerous tumor is, in particular, located within the patient's body 4.
[0072] In these different methods, the air flow rate is notably lower than that of the plasma-generating gas. In particular, the ratio between the air flow rate and the plasma-generating gas flow rate is less than or equal to 0.2. Such a ratio ensures a more intense cold plasma 2 at the target 3.
Claims
Demands
1. A treatment device (1) for a target (3) by cold atmospheric plasma (2) comprising an ionization chamber (10) of a plasma-generating gas stream including a dielectric barrier discharge (100), characterized in that the ionization chamber (10) comprises - an elongated body (200), and - a distribution head (300), where the dielectric barrier discharge (100) is configured on the one hand to apply a high-voltage current to the plasma-generating gas stream in order to obtain a cold atmospheric plasma stream formed of ionized plasma-generating gas and on the other hand to propagate a high-voltage current along the elongated body (200) to the distribution head (300) in order to maintain the ionization of the plasma-generating gas in the elongated body (200) to the distribution head (300),where the elongated body (200) is configured to carry the plasmagenic gas flow as well as the cold atmospheric plasma flow formed of ionized plasmagenic gas and an air flow to the distribution head (300), and where the distribution head (300) is configured to generate a cold atmospheric plasma comprising oxygenated and nitrogenous reagents (2) by ionization of the air flow by the cold atmospheric plasma flow formed of ionized plasmagenic gas.
2. Processing device (1) according to claim 1, wherein the elongated body (200) comprises a first transport conduit (51) configured to transport the plasmagenic gas flow and the cold atmospheric plasma flow formed from ionized plasmagenic gas and a second transport conduit (52) configured to transport the air flow, and wherein the second transport conduit (52) is disposed within all or part of the first transport conduit (51).
3. Processing device (1) according to claim 1 or 2, wherein the elongated body includes a third transport conduit (53) configured to recover exhaust gases from the distribution head (300).
4. Processing device (1) according to any one of claims 1 to 3, wherein the dielectric barrier discharge (100) comprises a propagation element (113) for the propagation of the high voltage, preferably the propagation element (113) is in the form of a metallic guide.
5. Processing device (1) according to any one of claims 1 to 4, wherein the distribution head (300) comprises a first distribution tube (311) for the cold atmospheric plasma flow formed of ionized plasmagenic gas and a second distribution tube (312) for the air flow, wherein one of the two tubes (311, 312) is electrically connected to the dielectric barrier discharge (100), preferably the dielectric barrier discharge (100) comprising a propagation element (113) for the propagation of the high voltage, one of the two tubes (311, 312) is electrically connected to the propagation element (113).
6. Processing device (1) according to claim 5, wherein the second distribution tube (312) is arranged inside the first distribution tube (311).
7. Processing device (1) according to claim 5 or 6, wherein the distal end of the second distribution tube (312) is located upstream of the distal end of the first distribution tube (311).
8. Processing device (1) according to any one of claims 1 to 7, wherein the delivery head (300) includes a perforation member (320) configured on the one hand to penetrate the target (3) and on the other hand to create a distribution space for the cold atmospheric plasma comprising oxygenated and nitrogenous reagents (2).
9. Processing device according to claim 6 or 7 and claim 8, wherein the perforation member (320) is mounted on the first distribution tube (311).
10. Method for the in vitro or ex vivo treatment of one or more cancerous tumor cells (3), said method comprising a step of inserting the delivery head (300) of the treatment device (1) according to any one of claims 1 to 9 into said at least one cancerous tumor cell (3), and a step of generating a cold atmospheric plasma comprising oxygenated and nitrogenous reagents (2) from a plasmagenic gas stream, an air stream and a high electrical voltage.