Plasma jet ion source, preparation method and application

Abstract

The present invention provides a plasma jet ion source, a preparation method and an application. The plasma jet ion source comprises: a mounting body, which is integrally formed and has a metal accommodating cavity, a positive electrode mounting position, a first injection hole and a carrier gas flow channel; the metal accommodating cavity is an annular structure, which is located in the mounting body to form a negative electrode mounting position, which is arranged opposite to the positive electrode mounting position, and there is a preset distance between the two; a positive electrode, which is fixed to the positive electrode mounting position; a negative electrode, which is filled in the metal accommodating cavity, and the melting point of the material of the negative electrode is lower than the melting point of the material of the mounting body. In the above-mentioned plasma jet ion source, since the mounting body is an integrally formed structure, the preset distance between the metal accommodating cavity and the positive electrode mounting position can be accurately controlled within 1 mm. The positive electrode is fixed on the positive electrode mounting position, so the electrode distance between the negative electrode and the positive electrode is the preset distance, which achieves the purpose of accurately controlling the electrode distance and accurately controlling the discharge distance.

Description

Technical Field

[0001] The present invention relates to the field of plasma medicine, and in particular to a plasma jet ion source, a preparation method and an application thereof. Background Art

[0002] Plasma medicine is an emerging discipline that studies the effects of plasma on living organisms. Atmospheric-pressure, low-temperature plasma jets, due to their safety, non-toxicity, residue-free nature, and low cost, have found widespread application in fields such as blood coagulation, cancer treatment, and pathogen inactivation. Atmospheric-pressure, low-temperature plasma can effectively induce apoptosis in cancer cells with minimal side effects on normal cells. Therefore, the use of atmospheric-pressure, low-temperature plasma jets for cancer treatment has become a research hotspot in plasma medicine. Currently, plasma jets have been shown to treat cancer not only by inducing apoptosis in cancer cells but also by affecting the cell cycle, inhibiting cancer cell proliferation, and inducing apoptosis in stem cells. Compared with traditional anti-cancer treatments, plasma jets offer shorter treatment cycles, faster efficacy, and minimal harm to the human body.

[0003] The electrode spacing of the plasma device currently under research basically remains above a few millimeters, and the exploration of the impact of smaller electrode spacing on the discharge effect is relatively limited, and the discharge spacing control is inaccurate. Summary of the Invention

[0004] The main purpose of the present invention is to provide a plasma jet ion source, a preparation method and an application thereof, so as to solve the technical problems of large electrode spacing and inaccurate discharge spacing control in a plasma device.

[0005] To achieve the above object, the present invention provides a plasma jet ion source, comprising:

[0006] The mounting body is integrally formed and comprises a metal housing cavity, a positive electrode mounting position, a first injection hole, and a carrier gas flow channel. The metal housing cavity is an annular structure located within the mounting body to form a negative electrode mounting position, opposite the positive electrode mounting position, with a predetermined spacing between them. The first injection hole is located on the side of the metal housing cavity away from the positive electrode mounting position and communicates with the metal housing cavity. The carrier gas flow channel extends through the mounting body and is located in the center of the metal housing cavity.

[0007] The positive electrode is fixed at the positive electrode mounting position.

[0008] A negative electrode is filled in the metal containing cavity, and the melting point of the material of the negative electrode is lower than the melting point of the material of the mounting body.

[0009] According to an embodiment of the present application, the number of the first injection holes is more than 2, and all of the first injection holes are connected to the metal receiving cavity and are evenly distributed around the metal receiving cavity.

[0010] According to an embodiment of the present application, the mounting body includes a first mounting body and an air sealing portion, a support column, a support surface and a needle fixing portion distributed on the top surface of the first mounting body.

[0011] The metal housing cavity and the first injection hole are located in the first mounting body. The gas sealing portion is located in the center of the first mounting body. Both have a needle hole extending therethrough, forming the positive electrode mounting position. The positive electrode is a hollow needle tube. The needle head is fixed in the needle head fixing portion, abutting against the support surface. The needle tip extends to the portion of the needle hole located in the first mounting body. The center of the hollow needle tube serves as the carrier gas flow channel.

[0012] According to an embodiment of the present application, the mounting body includes a second mounting body and an annular chamber protruding from the top surface of the second mounting body, the annular chamber forming the positive electrode mounting position. The positive electrode is a ring-shaped electrode that fills the positive electrode mounting position. The carrier gas flow channel is located at the center of the positive electrode mounting position.

[0013] According to an embodiment of the present application, the metal receiving cavities are multiple in number and are distributed in an array on the second mounting body. The negative electrodes corresponding to the number of the multiple metal receiving cavities are connected as one.

[0014] The annular chambers and carrier gas flow channels are each provided in a plurality, each corresponding to a metal receiving cavity. The second mounting body has a plurality of second injection holes surrounding and communicating with each of the annular chambers. The second mounting body also has a connecting passage connecting adjacent annular chambers, thereby connecting all positive electrodes.

[0015] According to the embodiment of the present application, the outsides of each metal containing cavity are completely connected to form a plate-shaped cavity, and each negative electrode is connected to form a plate-shaped structure, which has a plurality of circular holes corresponding to the inner diameter of the metal containing cavity.

[0016] The outer side of the second mounting body has a plurality of side openings communicating with the plate-shaped cavity.

[0017] According to an embodiment of the present application, the plasma jet ion source further comprises a gas hood, the upper opening of which is connected to an external vent pipe, and the lower opening of which is fitted with an outer peripheral surface of the second mounting body, for providing carrier gas to each carrier gas flow channel.

[0018] The upper opening of the gas cover is located at the center of the gas cover, and the aperture of each carrier gas flow channel gradually increases outward along the second mounting body.

[0019] The present application also discloses a method for preparing the above-mentioned plasma jet ion source, comprising the following steps:

[0020] The above-mentioned installation body is manufactured by 3D printing.

[0021] The Wood's alloy is placed in water at 97-100°C. After the Wood's alloy is melted, the Wood's alloy molten metal is injected into the corresponding cavity of the mounting body from the first injection hole and / or the second injection hole, and the corresponding electrodes are formed after cooling.

[0022] The present application also discloses an application of the above-mentioned plasma jet ion source in inducing apoptosis of glioma cells.

[0023] According to an embodiment of the present application, the preset spacing is 0.3-0.7 mm, the flow rate of the carrier gas is 0.05-0.5 L / min, the external AC voltage is 3-5.5 kV, and the voltage frequency is 18.5 kHz.

[0024] In the aforementioned plasma jet ion source, the mounting body is an integrally formed structure, allowing the preset spacing between the metal housing cavity and the positive electrode mounting position to be precisely controlled to within 1 mm. Molten metal is injected into the metal housing cavity through the first injection hole, allowing the negative electrode to rest closely on the surface of the metal housing cavity near the positive electrode mounting position, while the positive electrode is fixed to the positive electrode mounting position. Consequently, the distance between the negative and positive electrodes is the preset spacing, achieving precise control of the electrode spacing and, therefore, the discharge distance. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0026] Figure 1 This is a physical diagram of a plasma jet ion source according to one embodiment of the present application;

[0027] Figure 2 is a physical diagram of a plasma jet ion source according to another embodiment of the present application;

[0028] Figure 3 is a physical diagram of a plasma jet ion source according to another embodiment of the present application;

[0029] Figure 4 This is a discharge test circuit according to another embodiment of the present application;

[0030] Figure 5 This is a discharge diagram of the needle-ring structure of one embodiment of the present application at a spacing of 0.3 mm;

[0031] Figure 6 This is a discharge diagram of the needle-ring structure of one embodiment of the present application at a spacing of 0.5 mm;

[0032] Figure 7 This is a discharge diagram of the needle-ring structure of one embodiment of the present application at a spacing of 0.7 mm;

[0033] Figure 8 This is a discharge diagram of a ring-ring structure according to one embodiment of the present application at a spacing of 0.3 mm;

[0034] Figure 9 This is a discharge diagram of a ring-ring structure according to one embodiment of the present application at a spacing of 0.5 mm;

[0035] Figure 10 This is a discharge diagram of a ring-ring structure according to one embodiment of the present application at a spacing of 0.7 mm;

[0036] Figure 11 This is a discharge diagram of the array structure under different loading voltages according to one embodiment of the present application;

[0037] Figure 12 1 is the voltage and current waveform of a plasma jet ion source with different structures according to an embodiment of the present application;

[0038] Figure 13 It is the main spectral line of the emission spectrum of the plasma jet ion source with different structures in one embodiment of the present application;

[0039] Figure 14 1 is a diagram showing the distribution of active substances in plasma jet ion sources of different structures according to an embodiment of the present application;

[0040] Figure 15 This is a physical diagram of a plasma jet ion source with different structures according to an embodiment of the present application;

[0041] Figure 16 This is a diagram of active material distribution at different time lengths in a plasma jet ion source with different structures according to an embodiment of the present application;

[0042] Figure 17 This is a Hoechst staining result of cells treated with a needle-ring structure according to one embodiment of the present application;

[0043] Figure 18 This is a Hoechst staining result of cells treated with a ring-ring structure according to one embodiment of the present application;

[0044] Figure 19Schematic diagram of the structure of a plasma jet ion source (needle-ring structure) according to one embodiment of the present application;

[0045] Figure 20 yes Figure 19 Bottom view of

[0046] Figure 21 yes Figure 19 Front view of

[0047] Figure 22 yes Figure 21 BB cross-sectional view;

[0048] Figure 23 Schematic diagram of the structure of a plasma jet ion source (ring-ring structure) according to one embodiment of the present application;

[0049] Figure 24 yes Figure 23 Bottom view of

[0050] Figure 25 yes Figure 23 Front view of

[0051] Figure 26 yes Figure 25 AA sectional view;

[0052] Figure 27 Schematic diagram of the structure of a plasma jet ion source (array structure) according to one embodiment of the present application;

[0053] Figure 28 yes Figure 27 Front view of

[0054] Figure 29 yes Figure 28 AA sectional view;

[0055] Figure 30 yes Figure 28 BB cross-sectional view;

[0056] Figure 31 yes Figure 27 A top view of

[0057] Figure 32 yes Figure 31 AA section view.

[0058] The realization of the objectives, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings.

[0059] 100, mounting body; 110, metal receiving cavity; 120, positive electrode mounting position; 130, first injection hole; 140, carrier gas flow channel;

[0060] 200, first mounting body; 210, air sealing portion; 220, support column; 230, support surface; 240, needle fixing portion;

[0061] 300, second mounting body; 310, annular chamber; 320, second injection hole; 330, side opening; 340, connecting channel. DETAILED DESCRIPTION

[0062] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0063] It should be noted that all directional indications (such as up, down, etc.) in the embodiments of the present invention are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0064] In addition, the terms "first," "second," and so on, used in this disclosure are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, features specified as "first" or "second" may explicitly or implicitly include at least one of these features.

[0065] Moreover, the technical solutions between the various embodiments of the present invention may be combined with each other, but this must be based on the fact that ordinary technicians in this field can implement them. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0066] To achieve the above purpose, see Figures 19 to 22 、 Figure 23 、 Figure 27 The present invention provides a plasma jet ion source, including a mounting body 100, a positive electrode and a negative electrode.

[0067] The mounting body 100 is integrally formed, and the mounting body 100 has a metal accommodating cavity 110, a positive electrode mounting position 120, a first injection hole 130 and a carrier gas flow channel 140. The metal accommodating cavity 110 is an annular structure, which is located in the mounting body 100 to form a negative electrode mounting position, and is arranged opposite to the positive electrode mounting position 120, with a preset distance between the two. The first injection hole 130 is located on the side of the metal accommodating cavity 110 away from the positive electrode mounting position 120, and is connected to the metal accommodating cavity 110. The carrier gas flow channel 140 runs through the mounting body 100 and is located at the center of the metal accommodating cavity 110. The positive electrode is fixed to the positive electrode mounting position 120. The negative electrode is filled in the metal accommodating cavity 110, and the melting point of the material of the negative electrode is lower than the melting point of the material of the mounting body 100.

[0068] Conventional plasma jet ion sources are all split structures, relying primarily on manual control of one or both of the positive and negative electrodes to move them on a substrate or base and adjust the spacing between them. Manually adjusting the spacing can result in large errors, especially within a few millimeters or 1 mm, making it difficult to precisely control the spacing. Furthermore, the substrate or base is an assembled structure with multiple components, and errors in the components themselves and in the assembly gaps also exist. Furthermore, plasma jet ion sources are relatively small and require the substrate or base to be made of insulating materials. Therefore, the components connecting the substrate or base to the positive and negative electrodes are relatively thin and made of insulating materials, such as plastic, and therefore lack strength. During movement, deformation of the substrate or base may occur, leading to uncontrollable changes in the spacing between the positive and negative electrodes, such as changes in the spacing and accompanying changes in the alignment relationship between the positive and negative electrodes.

[0069] Based on this, the present application provides a plasma jet ion source. Figures 19 to 22 The mounting body 100 can be integrally formed through methods such as injection molding or 3D printing. The mounting body 100 includes a metal housing 110, a positive electrode mounting position 120, a first injection port 130, and a carrier gas flow channel 140. The relative position and preset spacing between the metal housing 110 and the positive electrode mounting position 120 are design values, and the specific structure is manufactured and molded based on these design values. The preset spacing is the target spacing between the positive and negative electrodes.

[0070] For ease of description, the metal housing cavity 110 of the mounting body 100 is defined as the bottom, and the positive electrode mounting position 120 of the mounting body 100 is defined as the top. The metal housing cavity 110 is located within the mounting body 100 and has a ring-shaped structure, corresponding to the negative electrode. The negative electrode is fixed within the mounting body 100, making it less likely to loosen, reducing the possibility of changes in the electrode spacing caused by loosening of the negative electrode. This approach also reduces the danger of exposed electrodes.

[0071] The first injection hole 130 is connected to the metal containing cavity 110 and is located on the lower surface of the metal containing cavity 110. When manufacturing the negative electrode, the mounting body 100 is inverted and the molten metal is injected from the first injection hole 130. That is, the negative electrode is injection-molded starting from the surface closest to the positive electrode mounting position 120 (the top surface of the metal containing cavity 110). In this way, under the action of gravity, the upper surface of the negative electrode is flat and closely attached to the top surface of the metal containing cavity 110. On the contrary, if the negative electrode is formed starting from the bottom surface of the metal containing cavity 110, the molten metal may not be fully filled due to factors such as degassing or surface tension, making the upper surface of the negative electrode uneven, resulting in inconsistent spacing between the positive and negative electrodes, affecting the discharge effect.

[0072] The melting point of the material of the negative electrode is lower than the melting point of the material of the mounting body 100. For example, the material of the negative electrode is Wood's metal or other alloy materials with a lower melting point. Wood's metal includes, in terms of mass percentage, 38-50% bismuth, 25-31% lead, 12.5-15% tin, and 12.5-16% cadmium. It has a low melting point and varies within a certain range depending on the specific element content, approximately between 60 and 70°C. During the experiment, it was found that the Wood's metal can be melted into tin-bismuth liquid metal in boiling water. The material of the mounting body 100 is a photosensitive resin with a melting point higher than 100°C, which prevents the molten metal from melting the mounting body 100 and causing changes in the electrode distance between the negative electrode and the positive electrode.

[0073] The carrier gas flow channel 140 is both a channel for carrier gas input and a channel for plasma jet ejection. The carrier gas flow channel 140 passes between the negative electrode and the positive electrode and is located at the center of the metal housing cavity 110, that is, ultimately at the center of the annular electrode.

[0074] In the aforementioned plasma jet ion source, since the mounting body 100 is an integrally formed structure, the preset spacing between the metal housing cavity 110 and the positive electrode mounting position 120 can be precisely controlled to within 1 mm. The molten metal is injected into the metal housing cavity 110 through the first injection hole 130 to begin filling. Therefore, the negative electrode is closely attached to the surface of the metal housing cavity 110 on the side near the positive electrode mounting position 120, while the positive electrode is fixed to the positive electrode mounting position 120. Therefore, the electrode spacing between the negative and positive electrodes is the preset spacing, achieving the purpose of precisely controlling the electrode spacing and accurately controlling the discharge distance.

[0075] According to the implementation of this application, see Figure 20 、 Figure 24 The number of the first injection holes 130 is more than 2, and all of them are connected to the metal accommodating cavity 110 and are evenly distributed around the metal accommodating cavity 110.

[0076] A plurality of first injection holes 130, for example, four, are evenly distributed around the metal receiving cavity 110. This allows injection into the metal receiving cavity 110 from different first injection holes 130. For example, molten metal can be injected into the metal receiving cavity 110 from different first injection holes 130 in turn, shortening the flow path of the molten metal and reducing the possibility of incomplete filling due to cooling during the flow of the molten metal. Furthermore, multiple first injection holes 130 facilitate the discharge of internal air, reducing the formation of bubbles in the negative electrode and facilitating complete filling.

[0077] In some embodiments, see Figures 19 to 22 The mounting body 100 includes a first mounting body 200 and an air sealing portion 210, a support column 220, a support surface 230 and a needle fixing portion 240 distributed on the top surface of the first mounting body 200. The metal accommodating cavity 110 and the first injection hole 130 are located in the first mounting body 200. The air sealing portion 210 is located at the center of the first mounting body 200, and the two have a needle hole passing through to form the positive electrode mounting position 120. The positive electrode is a hollow needle tube. The needle is fixed in the needle fixing portion 240 and abuts against the support surface 230. The needle tip extends to the part where the needle hole is located in the first mounting body 200. The center of the hollow needle tube is the carrier gas flow channel 140.

[0078] The plasma jet ion source of this type is a needle-ring structure device. There are multiple support columns 220, which are evenly distributed on the top surface of the first mounting body 200. In this way, under normal circumstances, the human fingertips cannot touch the hollow needle tube, which enhances safety. The top surface of the support column 220 is the support surface 230, and the needle fixing part 240 is fixed on the support surface 230. The positive electrode is a hollow needle tube, such as an injection needle, and the needle of the injection needle is fixed to the support surface 230 with a high-temperature hot melt adhesive. The needle tip of the injection needle passes through the air sealing part 210 and extends into the negative electrode. The design of the needle fixing part 240, the support column 220 and the injection needle meets the requirements for the electrode spacing between the needle tip of the injection needle and the negative electrode, which greatly reduces the error caused by manual installation of the electrode.

[0079] The needle hole facilitates securing the needle tip at the center of the annular ground electrode, aligned with the jet hole. Furthermore, after the needle is aligned with the jet hole, the top of the gas seal 210 can be sealed with high-temperature hot melt adhesive, so that helium can only be ejected through the jet hole, reducing helium waste and minimizing the use of expensive inert gas. An external vent tube is connected to the needle fixing portion 240, for example, by hot melt adhesive.

[0080] In some embodiments, when external wires are connected, the high-voltage wire is connected to the needle and sealed with hot-melt adhesive, and the ground wire is connected to the negative electrode and sealed with hot-melt adhesive.

[0081] In some embodiments, see Figures 23 to 26 The mounting body 100 includes a second mounting body 300 and an annular chamber 310 protruding from the top surface of the second mounting body 300. The annular chamber 310 forms the positive electrode mounting position 120. The positive electrode is an annular electrode and is filled in the positive electrode mounting position 120. The carrier gas flow channel 140 is located at the center of the positive electrode mounting position 120.

[0082] This type of plasma jet ion source is a ring-ring structure device, which is relatively simple to manufacture and can save materials. Two hollow cylinders are nested to form an annular chamber 310. The positive electrode in the positive electrode mounting position 120 can also be formed by referring to the aforementioned method of pouring molten metal, and its shape is annular. The negative electrode can be formed by referring to the aforementioned method of pouring molten metal. The edge of the annular chamber 310 has a notch to facilitate the access of external wires.

[0083] In some embodiments, see Figures 27 to 32 , the number of the metal accommodating cavities 110 is multiple, and they are distributed in an array on the second mounting body 300. The negative electrodes corresponding to the number of the multiple metal accommodating cavities 110 are connected as a whole. The number of the annular chambers 310 and the carrier gas flow channels are both multiple, and are arranged one-to-one with the metal accommodating cavities 110. The second mounting body 300 has a plurality of second injection holes 320 surrounding and connecting each of the annular chambers 310. The second mounting body 100 also has a connecting channel 340 between the adjacent annular chambers 310, so that all the positive electrodes are connected as a whole.

[0084] This method can be understood as an array-type ring-ring structure device. The positive electrodes of each ring-ring structure device are also connected in parallel. The annular chambers 310 are connected by a connecting channel 340. The connecting channel 340 is filled with molten metal to form a metal guide path, so that the positive electrodes in each annular chamber 310 are connected in parallel. The annular chamber 310 is surrounded by a plurality of second injection holes 320, and the second injection holes 320 inject molten metal to fill the annular chamber 310, and can also fill the connecting channel 340. Exemplarily, the nearest second injection hole 320 molten metal is selected from both ends of the connecting channel 340, and the connecting channel 340 is filled from both ends.

[0085] The negative electrodes of each ring-ring structure device are connected in parallel. The implementation method thereof can refer to the implementation method of the positive electrodes being connected in parallel, and will not be described in detail.

[0086] In some specific embodiments, the outer sides of the metal cavities 110 are completely connected to form a plate-shaped cavity, and the negative electrodes are connected to form a plate-shaped structure. The plate-shaped structure has a plurality of circular holes corresponding to the inner diameter of the metal cavities 110. The outer side of the second mounting body 300 has a plurality of side openings 330 connected to the plate-shaped cavity.

[0087] This method can be considered as not having an independent metal containing cavity 110, and the corresponding negative electrode is connected to form a plate-like structure. A circular hole in the plate-like structure can be considered as a ring of the negative electrode, forming a ring-ring structure with the corresponding ring-shaped electrode in the annular cavity 310. Since the above method does not have an independent metal containing cavity 110, the side opening 330 can also be used as an injection hole for the molten metal, thereby reducing the difficulty of forming the negative electrode. The side opening 330 can also serve as an access port for external wires.

[0088] In some embodiments, the plasma jet ion source further includes a gas hood, the upper opening of which communicates with an external vent, and the lower opening of which abuts against the outer circumference of the second mounting body 300 to provide carrier gas to each carrier gas flow channel. The upper opening of the gas hood is located at the center of the gas hood, and the aperture of each carrier gas flow channel gradually increases outward along the second mounting body 300.

[0089] This method uses the gas hood to simultaneously supply carrier gas to multiple carrier gas flow channels. Within the gas hood, the carrier gas velocity is high at the center and relatively weak at the edges. Therefore, the apertures of each carrier gas flow channel gradually increase outward along the second mounting body 300, balancing the effects of carrier gas velocity variations and ensuring a similar and uniform total amount of carrier gas output from each carrier gas flow channel.

[0090] The present application also discloses a method for preparing the above-mentioned plasma jet ion source, comprising the following steps:

[0091] The above-mentioned installation body is manufactured by 3D printing.

[0092] The Wood's alloy is placed in water at 97-100°C. After the Wood's alloy is melted, the Wood's alloy molten metal is injected into the corresponding cavity of the mounting body from the first injection hole and / or the second injection hole, and the corresponding electrodes are formed after cooling.

[0093] In this preparation method, 3D printing technology is used to produce plasma devices with different electrode spacings, reducing the electrode spacing and avoiding errors caused by manual splicing. A low-melting-point alloy is heated into a liquid and injected into the cavity structure reserved for the device to form an electrode. The electrode shape, electrode size, and electrode position can be flexibly changed according to specific needs. Compared with traditional electrode installation methods, the error can be controlled to a smaller level and the cost and time required for additional electrode processing are reduced. A 50μm quartz tube is loaded at the end of the device, which can accurately and targetedly treat cancer cells during experiments.

[0094] The present application also discloses an application of the above-mentioned plasma jet ion source in inducing apoptosis of glioma cells.

[0095] In some embodiments, the preset spacing is 0.3-0.7 mm, the flow rate of the carrier gas is 0.05-0.5 L / min, the external AC voltage is 3-5.5 kV, and the voltage frequency is 18.5 kHz.

[0096] The technical solution of this application is described below with reference to specific embodiments.

[0097] The following three atmospheric pressure dielectric barrier discharge plasma jet devices were designed using Solidworks 2022 software and printed using an Anycubic Phoyon M3 light-curing printer. To facilitate observation of experimental phenomena, translucent photosensitive resin materials were used for printing.

[0098] (1) Needle-ring structure device

[0099] The needle-ring device structure is as follows Figure 1 As shown, the overall size is 24×24×33 mm 3 The structure of the plasma device with an electrode spacing of 0.5 mm is described. The annular ground cavity is designed on a plate with a thickness of 3 mm and a size of 24×24 mm. 2 Inside the rectangular model is a hollow annular cavity with an outer diameter of 12 mm and an inner diameter of 4 mm, 0.5 mm from both the upper and lower surfaces of the annular ground electrode. To minimize the risk of exposed electrodes, four 2 mm diameter holes are drilled in the lower surface of this annular cavity to inject a low-melting-point alloy. The rest of the ground electrode is wrapped in an insulating resin layer. A 1 mm diameter hole is drilled in the center of the solid material inside this annular cavity to allow helium to flow. This facilitates securing the needle tip at the center of the annular ground electrode and aligning it with the jet orifice. Once the needle is aligned with the jet orifice, the top of the cylinder can be sealed with high-temperature hot melt adhesive, allowing helium to escape only through the jet orifice, reducing helium waste and minimizing the use of expensive inert gas.

[0100] An integrated mounting model was designed and printed based on the dimensions of a sterile injection needle. The four support posts were spaced 8 mm apart and 25 mm high, preventing fingertips from normally touching the high-voltage electrode. The needle was affixed to this surface with high-temperature hot-melt adhesive, ensuring that the needle tip was flush with the top surface of the annular ground electrode cavity model. This resulted in a 0.5 mm gap between the needle tip and the ground electrode, significantly reducing errors caused by manual electrode installation.

[0101] (2) Ring-ring structure device

[0102] Ring-ring device such as Figure 2 As shown, the overall size is 17×17×6 mm 3 ,and Figure 1 The difference between the devices is: Figure 2 The device's high-voltage and ground electrodes are both injected with low-melting-point alloys, and the size of the annular cavity is controlled to minimize material waste. The polar model still utilizes the annular polar cavity of the aforementioned needle-and-ring structure, while the high-voltage electrode is injected through the space formed by two nested hollow cylinders. A ventilation hose is connected to the hollow space of the inner cylinder to provide helium gas. Figure 2 The device electrode size is 1.5×2 mm.

[0103] (3) Array structure device

[0104] The overall size of the new 3×3 array structure device is 28×28×20 mm 3 ,like Figure 3 The high voltage electrode is still made of the above cavity structure, and in order to avoid voltage division, the cavities are connected to form a parallel structure to connect the high voltage electrodes, as shown in FIG. Figure 3 (a) As shown. The ground electrode is injected into a plate-type cavity that avoids the jet hole, and some holes are punched at the bottom of the cavity for injecting low-melting-point alloy, such as Figure 3 As shown in (b), both the high-voltage and low-voltage electrodes are designed within a rectangular resin layer with a side length of 28 mm and a height of 5 mm. The electrode spacing is 0.5 mm. A hole is left at the high-voltage electrode end to connect the helium hose, which is fixed with hot melt adhesive.

[0105] Circuit Connection

[0106] The circuit used in the experiment is as follows Figure 4 As shown, the high-voltage electrode of the plasma device is connected to the high-voltage output terminal of the CTP-2000K AC high-voltage power supply, and the discharge waveform is displayed by an oscilloscope; the ground electrode is connected to the output ground terminal of the AC high-voltage power supply; helium is introduced into the vent of the plasma jet device through a gas pipe connected to a flow display and a digital gas mass flowmeter.

[0107] Discharge test

[0108] To investigate the differences in the jet characteristics between the two different devices, as well as the same device at different spacings, the following experiments were designed for verification. To minimize error, the tests were repeated three times, all at atmospheric pressure, room temperature, and an 18.5 kHz frequency. The experimental circuit is as described above.

[0109] (1) Needle-ring structure discharge experiment

[0110] Since the outer diameter of the hollow injection needle used is only 0.3 mm, the air flow available for passing through is limited, and the carrier gas flow is restricted to 0.05 L / min.

[0111] When the electrode spacing is 0.3 mm, the plasma jet generation is as follows: Figure 5 As shown:

[0112] When the electrode spacing is 0.5 mm, the plasma jet generation is as follows: Figure 6 shown.

[0113] When the electrode spacing is 0.7 mm, the plasma jet generation is as follows: Figure 7 shown.

[0114] (2) Ring-ring structure discharge experiment

[0115] The helium flow rate was set at 5 L / min.

[0116] When the electrode spacing is 0.3 mm, the plasma jet generation Figure 8 shown.

[0117] Figure 8 Discharge diagram with a spacing of 0.3mm

[0118] When the electrode spacing is 0.5 mm, the plasma jet generation is as follows: Figure 9 shown.

[0119] Figure 9 Discharge diagram with a spacing of 0.5mm

[0120] When the electrode spacing is 0.7 mm, the plasma jet generation is as follows: Figure 10 shown.

[0121] Figure 10 Discharge diagram with a spacing of 0.7mm

[0122] (3) Array structure discharge experiment

[0123] The gas flow rate is 1.5 L / min, and the plasma jet generation is as follows Figure 11 shown.

[0124] By comparing the plasma jet images produced by different electrode spacings, three devices with better jet effects, 0.7 mm needle-ring, 0.5 mm ring-ring, and array structure, were selected for experiments.

[0125] Research Results and Analysis

[0126] Voltage and current waveforms and spectra of each device

[0127] In the discharge circuit, an ammeter (Pearson) is connected in series between the ground terminal of the plasma generator and the ground terminal of the AC power supply to measure the waveform. Figure 12 The voltage and current waveforms of different devices are shown respectively.

[0128] Although plasma jets are composed of many components, the key to influencing cell apoptosis is the active species. Therefore, it is of great significance to detect the plasma components generated by plasma devices. Figure 13 The spectra of each device are shown in Figure 1. From left to right, they are the needle-ring structure, ring-ring structure, and array structure. It can be seen that the spectral lines of helium and nitrogen are the most. The plasma components are OH radicals, N2, N2 + The presence of He, O, and He indicates a high concentration of active particles, demonstrating the presence of active particles capable of inducing cell apoptosis. The spectrum shows the highest intensity of the He atomic line, consistent with the experimental conditions. These active substances react with the culture medium to form H₂O₂, NO₂⁻, or NO₃⁻.

[0129] Figure 13 The main spectral lines of the emission spectra of each device. (a) Needle-ring spectrum. (b) Ring-ring spectrum. (c) Array spectrum

[0130] Active substance characterization experiments

[0131] Since the active substances generated by low-temperature plasma react with potassium ions in the starch potassium iodide solution to generate iodine, the starch solution can appear blue-purple. Therefore, this experiment was used to observe the active substances produced by each device. The three devices used the same treatment conditions: the treatment distance was 2 mm (the distance between the bottom of the plasma jet device and the starch potassium iodide agar culture medium), the AC voltage was 3 kV, the power supply frequency was 18.5 kHz, and the color and distribution changes of the starch potassium iodide agar culture medium were observed. The experimental results are shown in the figure. Figure 14 As shown. Figure 14In the figure, a is the characterization results of active substances of needle-ring at different treatment times: (a) 2 min, (b) 4 min, (c) 6 min; b is the characterization results of active substances of ring-ring at different treatment times: (d) 2 min, (e) 4 min, (f) 6 min; c is the characterization results of active substances of array at different treatment times: (g) 2 min, (h) 4 min, (i) 6 min.

[0132] The surface of the starch potassium iodide agar medium treated with the plasma jet exhibits a bluish-purple color, with hollow, circular areas appearing. As treatment time increases, the distribution of reactive species such as ROS and RNS gradually increases and their color becomes darker. This indicates that the generation of reactive species by the low-temperature plasma jet is increasing.

[0133] Plasma device treatment cell experiment

[0134] To compare the effects of the needle-ring and ring-ring devices on human brain glioma H4 cells, an experimental verification was conducted. Both devices used a hollow elastic quartz capillary with an inner diameter of 50 μm placed in a 1 mm jet hole. Figure 15 shown.

[0135] To ensure that the 50 μm hollow elastic quartz capillary did not hinder the ejection of the active substance, starch potassium iodide agar plates were used for testing. The experimental results are shown in Figure 2. Figure 16 As shown in the figure, (a) shows the ejection of the needle-ring structure at different treatment times and an enlarged image: (a) 30 s, (b) 60 s, (c) 90 s, (d) 2 min, (e) 4 min, (f) 6 min; (b) shows the ejection of the ring-ring structure at different treatment times and an enlarged image: (g) 30 s, (h) 60 s, (i) 90 s, (j) 2 min, (k) 4 min, (l) 6 min. It can be clearly observed that the distribution range of the active substance is restricted to a smaller range, but this does not prevent the ejection of the active substance.

[0136] Subsequently, a cell treatment experiment was conducted. The AC voltage was 3 kV, the voltage frequency was 18.5 kHz, and the helium flow rate was 0.5 L / min. The ends of the hollow elastic quartz capillaries of the two devices were inserted 2 mm below the liquid surface, and H4 cells were treated with the two plasma devices for 0 min, 5 min, and 10 min, respectively. Hoechest reagent was used to identify cell apoptosis, and the cells were observed after 24 h of treatment. The apoptosis results are shown in Figure 2. Figure 17 、 18As shown in the figure, as the plasma device treated cells for an extended period of time, the overall coloration and brightness of the cells within the field of view increased, and the overall staining distribution was significantly higher than that of normal living cells. However, cells exhibiting uneven staining and brightness distribution within the field of view were relatively rare, indicating that the active substances generated by the plasma jet successfully induced cell apoptosis. The device has a significant effect on cell apoptosis.

[0137] The above technical solutions of the present invention are only preferred embodiments of the present invention and do not limit the patent scope of the present invention. All equivalent structural transformations made by using the contents of the present invention's description and drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A plasma jet ion source, characterized in that: include: The mounting body is integrally formed and has a metal accommodating cavity, a positive electrode mounting position, a first injection hole, and a carrier gas flow channel; the metal accommodating cavity is an annular structure, located within the mounting body to form a negative electrode mounting position, which is arranged opposite to the positive electrode mounting position with a preset distance between the two; the first injection hole is located on the side of the metal accommodating cavity away from the positive electrode mounting position and is in communication with the metal accommodating cavity; the carrier gas flow channel runs through the mounting body and is located at the center of the metal accommodating cavity; The mounting body includes a first mounting body and an air sealing portion, a support column, a support surface, and a needle fixing portion distributed on the top surface of the first mounting body; the metal accommodating cavity and the first injection hole are located in the first mounting body; the air sealing portion is located in the center of the first mounting body, and the two have a needle hole passing through, forming the positive electrode mounting position, the positive electrode is a hollow needle tube, the needle is fixed in the needle fixing portion and abuts against the support surface, the needle tip extends to the part of the needle hole located in the first mounting body, and the center of the hollow needle tube is the carrier gas flow channel; Alternatively, the mounting body includes a second mounting body and an annular chamber protruding from the top surface of the second mounting body, the annular chamber forming the positive electrode mounting position; the positive electrode is an annular electrode filled in the positive electrode mounting position; the carrier gas flow channel is located at the center of the positive electrode mounting position; A positive electrode, fixed at the positive electrode mounting position; A negative electrode is filled in the metal containing cavity, and the melting point of the material of the negative electrode is lower than the melting point of the material of the mounting body.

2. The plasma jet ion source according to claim 1, characterized in that: The number of the first injection holes is more than 2, and all of the first injection holes are connected to the metal containing cavity and are evenly distributed around the metal containing cavity.

3. The plasma jet ion source according to claim 1, characterized in that: There are multiple metal accommodating cavities, which are distributed in an array on the second mounting body; the negative electrodes corresponding to the multiple metal accommodating cavities are connected as a whole; There are multiple annular chambers and multiple carrier gas flow channels, and they are all arranged one-to-one with the metal containing cavity; the second mounting body has multiple second injection holes surrounding and connecting each of the annular chambers; the second mounting body also has a connecting channel between adjacent annular chambers, so that all positive electrodes are connected as one.

4. The plasma jet ion source according to claim 3, characterized in that: The outsides of the metal accommodating cavities are completely connected to form a plate-shaped cavity, and the negative electrodes are connected to form a plate-shaped structure. The plate-shaped structure has a plurality of circular holes corresponding to the inner diameter of the metal accommodating cavities; The outer side of the second mounting body has a plurality of side openings communicating with the plate-shaped cavity.

5. The plasma jet ion source according to claim 3, characterized in that: The plasma jet ion source further includes a gas hood, the upper opening of which is connected to an external vent pipe, and the lower opening of which is in contact with the outer peripheral surface of the second mounting body, for providing carrier gas to each carrier gas flow channel; The upper opening of the gas cover is located at the center of the gas cover, and the aperture of each carrier gas flow channel gradually increases outward along the second mounting body.

6. A method for preparing a plasma jet ion source according to any one of claims 1 to 5, characterized in that: The following steps are involved: Producing the mounting body according to any one of claims 1 to 5 by 3D printing; The Wood's alloy is placed in water at 97-100°C. After the Wood's alloy is melted, the Wood's alloy molten metal is injected into the corresponding cavity of the mounting body from the first injection hole and / or the second injection hole, and the corresponding electrodes are formed after cooling.

7. Use of the plasma jet ion source according to any one of claims 1 to 5 in inducing apoptosis of glioma cells.

8. The use according to claim 7, characterized in that The preset spacing is 0.3-0.7 mm, the flow rate of the carrier gas is 0.05-0.5 L / min, the external AC voltage is 3-5.5 kV, and the voltage frequency is 18.5 kHz.

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