Plasma jet ion source, preparation method and application

Abstract

The invention provides a plasma jet ion source, a preparation method and application, and the plasma jet ion source comprises a mounting body which is integrally formed and is provided with a metal accommodation cavity, a positive electrode mounting position, a first injection hole and a carrier gas flow channel; the metal accommodating cavity is of an annular structure, is positioned in the mounting body to form a negative electrode mounting position, is opposite to the positive electrode mounting position, and is spaced from the positive electrode mounting position by a preset distance; the positive electrode is fixed at the positive electrode mounting position; and the metal containing cavity is filled with the negative electrode, and the melting point of the material of the negative electrode is lower than that of the material of the mounting body. According to the plasma jet ion source, the installation body is of the integrally-formed structure, and the preset distance between the metal containing cavity and the positive electrode installation position can be accurately controlled within 1 mm. The positive electrode is fixed on the positive electrode mounting position, so that the electrode distance between the negative electrode and the positive electrode is the preset distance, and the purposes of accurately controlling the electrode distance and accurately controlling the discharge distance are achieved.

Description

Technical Field

[0001] The 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 organisms. Atmospheric pressure low-temperature plasma jets have been widely used in many fields such as blood coagulation, cancer treatment, and pathogen inactivation due to their safety, non-toxicity, no residue, and low cost. Atmospheric pressure low-temperature plasma can effectively induce apoptosis of cancer cells, and the side effects on normal cells are extremely limited. Therefore, the use of atmospheric pressure low-temperature plasma jets to treat cancer has also become a research hotspot in plasma medicine. It has been found that the treatment of cancer with plasma jets not only includes inducing apoptosis of cancer cells, but also includes affecting the cell cycle of cancer cells, inhibiting cancer cell proliferation, and inducing apoptosis of stem cells. Compared with traditional anti-cancer methods, plasma jets have the characteristics of short treatment cycle, fast effectiveness, and less harm to the human body.

[0003] The electrode spacing of the plasma device currently under research basically remains above a few millimeters, while 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 has a metal receiving cavity, a positive electrode mounting position, a first injection hole, and a carrier gas flow channel. The metal receiving cavity is an annular structure, which is located in the mounting body to form a negative electrode mounting position, and is arranged opposite to the positive electrode mounting position, and there is a preset distance between the two. The first injection hole is located on the side of the metal receiving cavity away from the positive electrode mounting position, and is connected to the metal receiving cavity. The carrier gas flow channel runs through the mounting body and is located at the center of the metal receiving 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 containing cavity and are evenly distributed around the metal containing 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 containing cavity and the first injection hole are located in the first mounting body. The gas sealing part is located in the center of the first mounting body, and the two have a pinhole penetrating therethrough to form the positive electrode mounting position. The positive electrode is a hollow needle tube, and the needle head is fixed in the needle head fixing part to abut against the supporting surface, and the needle tip extends to the part where the pinhole is located in the first mounting body, and the center of the hollow needle tube is 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, and the annular chamber forms 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.

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

[0014] The number of the annular chambers and the carrier gas channels are both multiple, and are arranged one-to-one with the metal containing chamber. 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 connecting adjacent annular chambers, so that all positive electrodes are connected as one.

[0015] According to the implementation manner of the present application, the outer sides of each metal containing cavity are completely connected to form a plate-like cavity, and each negative electrode is connected to form a plate-like structure, and the plate-like structure 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, an upper opening of which is connected to an external ventilation pipe, and a lower opening of which is fitted to an outer peripheral surface of the second mounting body, for providing carrier gas to each carrier gas 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 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 chamber of the installation body from the first injection hole and / or the second injection hole, and the corresponding electrode is 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 implementation manner of the present application, the preset spacing is 0.3 to 0.7 mm, the flow rate of the carrier gas is 0.05 to 0.5 L / min, the external AC voltage is 3 to 5.5 kV, and the voltage frequency is 18.5 kHz.

[0024] In the above-mentioned plasma jet ion source, since the mounting body is an integrally formed structure, the preset spacing between the metal receiving cavity and the positive electrode mounting position can be precisely controlled within 1 mm. The molten metal is injected into the metal receiving cavity from the first injection hole to start filling, so the negative electrode is closely attached to the surface of the metal receiving cavity on the side close to the positive electrode mounting position, and the positive electrode is fixed on the positive electrode mounting position, so the electrode spacing between the negative electrode and the positive electrode is the preset spacing, achieving the purpose of precisely controlling the electrode spacing and accurately controlling the discharge spacing. 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 drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. 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 creative work.

[0026] Figure 1 is a physical diagram of a plasma jet ion source according to an 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 It is a discharge test circuit of another embodiment of the present application;

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

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

[0032] Figure 7 This is a discharge diagram of a needle-ring structure according to an 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 an embodiment of the present application at a spacing of 0.3 mm;

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

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

[0036] Fig.11 This is a discharge diagram of an array structure of an embodiment of the present application under different loading voltages;

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

[0038] Fig.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] Fig.14 is a distribution diagram of active substances of plasma jet ion sources with different structures according to one embodiment of the present application;

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

[0041] Fig.16 This is a distribution diagram of active substances in different time lengths of plasma jet ion sources with different structures according to one embodiment of the present application;

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

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

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

[0045] Fig. 20 yes Fig.19 Bottom view of

[0046] Fig.21 yes Fig.19 A front view of

[0047] Fig. 22 yes Fig.21 BB section view;

[0048] Fig.23 is a schematic structural diagram of a plasma jet ion source (ring-ring structure) according to an embodiment of the present application;

[0049] Fig.24 yes Fig.23 Bottom view of

[0050] Fig.25 yes Fig.23 A front view of

[0051] Fig.26 yes Fig.25 AA section view;

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

[0053] Fig.28 yes Fig. 27 A front view of

[0054] Fig.29 yes Fig.28 AA section view;

[0055] Fig.30 yes Fig.28 BB section view;

[0056] Fig.31 yes Fig. 27 A top view of

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

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

[0059] 100, mounting body; 110, metal containing 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 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 described embodiments 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 creative work 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 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, in the present invention, the descriptions such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features.

[0065] Furthermore, 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 they can be implemented by ordinary technicians in the field. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such 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 Figure 19 to Figure 22 , Fig.23 , Fig. 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, and there is 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, which mainly rely on manual control of one or both of the positive electrode and the negative electrode to move them on the substrate or base to adjust the distance between them. Manual adjustment of the distance has a large error, especially within a few millimeters or 1 mm, it is difficult to accurately control the distance, and the substrate or base is a multi-component assembly structure, and there are also errors in the errors of the components themselves and the assembly gap. Moreover, the plasma jet ion source is small in size and requires the substrate or base to be an insulating material. Therefore, the parts connecting the substrate or base to the positive electrode and the negative electrode are relatively slender and are made of insulating materials, such as plastic, so their strength is insufficient. During the movement process, the substrate or base may deform, resulting in uncontrollable changes in the distance between the positive electrode and the negative electrode, such as changes in the distance and changes in the alignment relationship between the positive electrode and the negative electrode.

[0069] Based on this, the present application provides a plasma jet ion source. Figure 19 to Figure 22 The mounting body 100 can be integrally formed by injection molding or 3D printing. The mounting body 100 includes a metal receiving cavity 110, a positive electrode mounting position 120, a first injection hole 130, and a carrier gas flow channel 140. The relative position and preset spacing between the metal receiving cavity 110 and the positive electrode mounting position 120 are design values, and the specific structure is manufactured and formed according to the design values. The preset spacing is the target spacing between the positive electrode and the negative electrode.

[0070] For ease of description, one end of the metal receiving cavity 110 of the mounting body 100 is defined as the bottom, and one end of the positive electrode mounting position 120 of the mounting body 100 is defined as the top. The metal receiving cavity 110 is arranged inside the mounting body 100, which is a ring-shaped structure, and the corresponding negative electrode is a ring-shaped electrode. The negative electrode is fixedly arranged inside the mounting body 100 and is not prone to loosening, which reduces the probability of changes in the electrode spacing caused by loosening of the negative electrode. Moreover, this method can also reduce the danger caused by exposed electrodes.

[0071] The first injection hole 130 is connected to the metal containing cavity 110, and the first injection hole 130 is located on the lower surface of the metal containing cavity 110. When making 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 injected and molded from the surface closest to the positive electrode mounting position 120 (the top surface of the metal containing cavity 110), so that under the action of gravity, the upper surface of the negative electrode is flat and close to the top surface of the metal containing cavity 110. On the contrary, if the negative electrode is formed from the bottom surface of the metal containing cavity 110, the molten metal may not be filled due to exhaust or surface tension, making the upper surface of the negative electrode uneven, resulting in inconsistent spacing between the positive electrode and the negative electrode, 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 alloy or other alloy materials with a lower melting point. Wood's alloy includes, by mass percentage, 38-50% bismuth, 25-31% lead, 12.5-15% tin, and 12.5-16% cadmium. It has a low melting point. Depending on the specific element content, the melting point varies within a certain range, about 60-70°C. During the experiment, it was found that the Wood's alloy can be melted into tin-bismuth metal liquid in boiling water. The material of the mounting body 100 is a photosensitive resin, and its melting point is higher than 100°C, which prevents the molten metal from melting the mounting body 100, causing the electrode spacing between the negative electrode and the positive electrode to change.

[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 containing cavity 110, that is, ultimately located at the center of the annular electrode.

[0074] In the above-mentioned plasma jet ion source, since the mounting body 100 is an integrally formed structure, the preset spacing between the metal receiving cavity 110 and the positive electrode mounting position 120 can be precisely controlled within 1 mm. The metal melt is injected into the metal receiving cavity 110 from the first injection hole 130 to start filling, so the negative electrode is closely attached to the surface of the metal receiving cavity 110 on the side close to the positive electrode mounting position 120, and the positive electrode is fixed on the positive electrode mounting position 120, so the electrode spacing between the negative electrode and the positive electrode is the preset spacing, achieving the purpose of precisely controlling the electrode spacing and accurately controlling the discharge spacing.

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

[0076] The number of first injection holes 130 is relatively large, for example, 4 are evenly distributed around the metal receiving cavity 110. The metal receiving cavity 110 can be injected from different first injection holes 130, for example, the molten metal can be injected from different first injection holes 130 in turn, shortening the flow path of the molten metal, thereby reducing the possibility of incomplete filling caused by cooling during the flow of the molten metal. In addition, multiple first injection holes 130 are conducive to the discharge of internal air, reducing the formation of bubbles in the negative electrode, and facilitating complete filling.

[0077] In some embodiments, see Figure 19 to Figure 22 The mounting body 100 includes a first mounting body 200 and a gas 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 gas sealing portion 210 is located at the center of the first mounting body 200, and the two have a needle hole penetrating therethrough to form the positive electrode mounting position 120. The positive electrode is a hollow needle tube, and the needle is fixed in the needle fixing portion 240 and abuts against the support surface 230. The needle tip extends to the portion where the needle hole is located in the first mounting body 200, and 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] On the one hand, the needle hole is convenient for fixing the needle tip at the center of the annular ground electrode and aligning with the jet hole. On the other hand, after the needle is aligned with the jet hole, the top of the sealing part 210 can be sealed with a high-temperature hot melt adhesive so that helium can only be ejected through the jet hole, reducing the waste of helium and minimizing the amount of expensive inert gas. The external ventilation pipe is connected to the needle fixing part 240, such as fixed and sealed by hot melt adhesive.

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

[0081] In some embodiments, see Figure 23 to Figure 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, and the annular chamber 310 forms the positive electrode mounting position 120. The positive electrode is an annular electrode 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] The plasma jet ion source of this method 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 molding method of 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 for facilitating the access of external wires.

[0083] In some embodiments, see Figure 27 to Figure 32 , the number of the metal containing 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 containing cavities 110 are connected as a whole. The number of the annular chambers 310 and the carrier gas channels are both multiple, and they are arranged one-to-one with the metal containing 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-to-ring structure device are connected in parallel, and the implementation method thereof can refer to the implementation method of the positive electrodes being connected in parallel, which will not be described in detail.

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

[0087] This method can be regarded 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 regarded as a ring of the negative electrode, forming a ring-ring structure with the corresponding ring-shaped electrode in the annular chamber 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 be used as an access port for an external wire.

[0088] In some embodiments, 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 in contact with the outer peripheral surface of the second mounting body 300, so as to provide carrier gas for each carrier gas channel. The upper opening of the gas hood is located at the center of the gas hood, and the aperture of each carrier gas channel gradually increases outward along the second mounting body 300.

[0089] This method provides carrier gas to multiple carrier gas channels at the same time through the gas hood. In the gas hood, the carrier gas flow rate in the center is large, and the carrier gas flow rate at the edge is relatively weakened, so the aperture of each carrier gas channel gradually increases outward along the second mounting body 300, balancing the influence of the change in carrier gas flow rate, so that the total amount of carrier gas output by each carrier gas channel is similar and relatively uniform.

[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 chamber of the installation body from the first injection hole and / or the second injection hole, and the corresponding electrode is formed after cooling.

[0093] In this preparation method, 3D printing technology can be used to make plasma devices with different electrode spacings, which reduces the electrode spacing and avoids errors caused by manual splicing. A low-melting-point alloy is heated into a liquid state and injected into the cavity structure reserved in the device to form an electrode. The electrode shape, electrode size and electrode position can be flexibly changed according to specific needs. Compared with the traditional electrode installation method, the error can be controlled to be smaller 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 the experiment.

[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 the present application is described below in conjunction with specific embodiments.

[0097] The following three atmospheric pressure dielectric barrier discharge plasma jet devices were designed using Solidworks2022 software and printed using Anycubic Phoyon M3 light-curing printer. To facilitate the 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 24×24×33mm 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 3 mm thick and 24×24 mm 2 Inside the rectangular model is a hollow annular cavity with a distance of 0.5mm from the upper and lower surfaces of the annular ground electrode, an outer diameter of 12mm, and an inner diameter of 4mm. In order to avoid the danger caused by the exposed electrode, four holes with a diameter of 2mm are punched on the lower surface of the annular cavity to inject low-melting-point alloy, and the rest of the ground electrode is wrapped with an insulating resin layer. A hole with a diameter of 1mm is punched in the middle of the solid material inside the annular cavity to pass helium. On the one hand, it is convenient to fix the needle tip in the center of the annular ground electrode and align it with the jet hole. On the other hand, after the needle is aligned with the jet hole, the top of the cylinder can be sealed with high-temperature hot melt adhesive so that helium can only be ejected through the jet hole, reducing the waste of helium and minimizing the use of expensive inert gas.

[0100] An integrated installation model was designed and printed according to the size of the sterile injection needle. The four pillars of the support plane are 8mm apart and 25mm high. Normally, human fingertips cannot touch the high-voltage electrode. The injection needle is fixed on this plane with a high-temperature hot melt adhesive to ensure that the needle tip is flush with the upper surface of the annular ground electrode cavity model, that is, the distance between the needle tip and the ground electrode is 0.5mm, which greatly reduces the error caused by manual electrode installation.

[0101] (2) Ring-Ring Structure Device

[0102] Ring-ring device Figure 2 As shown, the overall size is 17×17×6mm 3 ,and Figure 1 The difference between the devices is: Figure 2 The high-voltage electrode and grounding electrode of the device are injected with low-melting-point alloys, and the size of the annular cavity is reduced within a controllable range to avoid material waste. The geodetic model still uses the annular geodetic cavity in the needle-ring structure mentioned above, while the high-voltage electrode is injected from the space formed by the nesting of two hollow cylinders, and the ventilation hose is connected to the hollow part of the inner cylinder to connect helium. Figure 2 The device electrode size is 1.5×2mm.

[0103] (3) Array structure device

[0104] The overall size of the new 3×3 array structure device is 28×28×20mm 3 ,like Figure 3 As shown. The high-voltage electrode is still made of the above-mentioned cavity structure, and in order to avoid the generation of partial pressure, the cavities are connected to form a parallel structure to connect the high-voltage electrodes. The ground electrode is injected using a plate-type cavity that avoids the jet hole, and some holes are punched at the bottom of the cavity for the injection of low-melting-point alloy. Both the high-voltage electrode and the low-voltage electrode are designed in a rectangular resin layer with a side length of 28mm and a height of 5mm. The electrode spacing is 0.5mm. A hole is left at the high-voltage electrode end to connect the helium hose and fix it 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] In order to explore the similarities and differences of the jet characteristics of two different devices and the same device at different spacings, the following experiment is designed for verification. To reduce errors, the test is repeated three times, and the experimental environment is atmospheric pressure, room temperature, and the frequency is 18.5kHz. 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 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 to 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 Fig. 9 shown.

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

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

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

[0122] (3) Array structure discharge experiment

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

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

[0125] Research Results and Analysis

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

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

[0128] Although there are many components in plasma jet, the key to affecting cell apoptosis is active particles. Therefore, it is of great significance to detect the plasma components generated by plasma devices. Fig.13 The following are the spectra of each device. From left to right, they are the spectra of the needle-ring structure, the ring-ring structure, and the array structure. It can be found that the spectral lines of helium and nitrogen are the most. The plasma components include OH radicals, N2, N2 + , He, O, indicating that there are more active particles and the active particles have the conditions to induce cell apoptosis. From the spectrum, it can be observed that the He atomic spectral line intensity is the highest, which is consistent with the experimental conditions. These active substances will react with the culture medium to form H2O2, NO2- or NO3-.

[0129] Fig.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 produced 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 is used to observe the active substances produced by each device. The three devices use the same treatment conditions: the treatment distance is 2mm (the distance between the bottom of the plasma jet device and the starch potassium iodide agar culture medium), the AC voltage is 3kV, the power supply frequency is 18.5kHz, and the color and distribution changes of the starch potassium iodide agar culture medium are observed. The experimental results are as follows Fig.14 As shown. Fig.14 In the figure, a is the characterization results of active substances in needle-ring at different treatment times: (a) 2 min, (b) 4 min, (c) 6 min; b is the characterization results of active substances in ring-ring at different treatment times: (d) 2 min, (e) 4 min, (f) 6 min; c is the characterization results of active substances in array at different treatment times: (g) 2 min, (h) 4 min, (i) 6 min.

[0132] It can be seen that the surface of the starch potassium iodide agar medium treated with plasma jet is blue-purple, and the shape is a hollow, ring-shaped circular area. As the treatment time increases, the distribution range of active particles such as ROS and RNS gradually increases and the color becomes darker. This indicates that the number of active particles generated by the low-temperature plasma jet is increasing.

[0133] Plasma device treatment cell experiment

[0134] In order to compare the effects of the needle-ring structure and the ring-ring structure on human brain glioma cells H4, an experimental verification was conducted. Both devices use a hollow elastic quartz capillary with an inner diameter of 50 μm placed in a 1 mm jet hole. Fig.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 Fig.16 As shown, a is the spraying condition and enlarged image of the needle-ring structure at different treatment times: (a) 30s, (b) 60s, (c) 90s, (d) 2min, (e) 4min, (f) 6min; b is the spraying condition and enlarged image of the ring-ring structure at different treatment times: (g) 30s, (h) 60s, (i) 90s, (j) 2min, (k) 4min, (l) 6min. It can be clearly observed that the distribution range of the active substance is restricted to a smaller size, but it does not prevent the active substance from spraying.

[0136] Then the cell treatment experiment was carried out. The AC voltage was 3kV, the voltage frequency was 18.5kHz, and the helium flow rate was 0.5L / min. The ends of the hollow elastic quartz capillaries of the above two devices were extended 2mm below the liquid surface, and the H4 cells were treated with the two plasma devices for 0min, 5min, and 10min respectively. The Hoechest reagent was used to identify the cell apoptosis, and the treatment was observed after 24h. The apoptosis results are shown in Fig.17 , 18 As shown. It can be observed that as the plasma device treats cells for a longer time, the overall coloring and brightness of the cells in the field of view increase, and the overall staining distribution is significantly higher than that of normal living cells. However, there are fewer cells in the field of view that show uneven staining distribution and brightness distribution, 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 the patent scope of the present invention is not limited thereto. All equivalent structural changes made by using the contents of the present invention specification 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, and 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; the first injection hole is located on the side of the metal accommodating cavity away from the positive electrode mounting position, and is connected to 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; 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: The mounting body comprises 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 part is located in the center of the first mounting body, and both have a needle hole penetrating therethrough to form the positive electrode mounting position. The positive electrode is a hollow needle tube, and the needle is fixed in the needle fixing part and abuts against the supporting surface. The needle tip extends to the part where the needle hole is located in the first mounting body, and the center of the hollow needle tube is the carrier gas flow channel.

4. The plasma jet ion source according to claim 1, characterized in that: The mounting body includes a second mounting body and an annular chamber protruding from the top surface of the second mounting body, wherein the annular chamber forms the positive electrode mounting position; the positive electrode is an annular electrode filled in the positive electrode mounting position; and the carrier gas flow channel is located at the center of the positive electrode mounting position.

5. The plasma jet ion source according to claim 4, characterized in that: The number of the metal containing cavities is multiple and they are distributed in an array on the second mounting body; the negative electrodes corresponding to the number of the multiple metal containing cavities are connected as a whole; The number of the annular chambers and the carrier gas channels are both multiple, and are arranged one-to-one with the metal containing chamber; 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.

6. The plasma jet ion source according to claim 5, characterized in that: The outer sides 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, and the plate-shaped structure has a plurality of circular holes corresponding to the inner diameter of the metal containing cavity; The outer side of the second mounting body has a plurality of side openings communicating with the plate-shaped cavity.

7. The plasma jet ion source according to claim 5, characterized in that: The plasma jet ion source further comprises a gas hood, the upper opening of which is in communication with 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 channel; The upper opening of the gas cover is located at the center of the gas cover, and the aperture of each carrier gas channel gradually increases outward along the second mounting body.

8. A method for preparing a plasma jet ion source according to any one of claims 1 to 7, characterized in that: The following steps are involved: Manufacturing the mounting body according to any one of claims 1 to 7 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 chamber of the installation body from the first injection hole and / or the second injection hole, and the corresponding electrode is formed after cooling.

9. Use of the plasma jet ion source according to any one of claims 1 to 9 in inducing apoptosis of glioma cells.

10. The use according to claim 9, 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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