A wireless charging, wireless control micro-implantable biosafe tumor hyperthermia device

Abstract

This invention discloses a miniature implantable biosafety tumor hyperthermia device that is wirelessly rechargeable and wirelessly controlled. Prioritizing biosafety, the device is fabricated using a series of safe materials; it utilizes a biosafety battery, coupled with a wireless charging module to provide long-term power; and it employs a customized heating module to uniformly and accurately raise the module temperature to the required level. The device is implanted after surgical removal of the tumor, enabling periodic and precise postoperative hyperthermia treatment, achieving wireless charging power supply and wireless control switching.

Description

Technical Field

[0001] This invention belongs to the field of medical device technology, specifically relating to a miniature implantable biosafety tumor hyperthermia device that can be wirelessly charged and wirelessly controlled. Background Technology

[0002] Cancer remains a leading cause of death worldwide, characterized by uncontrolled cell proliferation, invasiveness, and metastatic potential. Surgery, chemotherapy, and radiotherapy are the mainstream treatments for cancer. Surgery is the primary treatment for most malignant solid tumors; however, due to the difficulty in defining tumor boundaries, infiltration into surrounding tissues, and anatomically palpable tumor locations, complete resection is challenging, and incomplete resection significantly increases the risk of local recurrence and metastasis. While chemotherapy and radiotherapy are effective, systemic treatments are often limited by insufficient spatial precision (poor specificity) and severe side effects. Postoperative treatment of cancer remains a difficult challenge.

[0003] Hyperthermia is an emerging cancer treatment method that achieves precise and minimally invasive tumor ablation through localized heating. Traditional postoperative tumor hyperthermia methods use expensive, large-scale equipment to wirelessly and locally heat the tumor using electromagnetic, ultrasonic, and thermal conduction technologies. This requires repeated treatments, is expensive and inconvenient. Furthermore, due to the irregular growth of tumors and the difficulty in defining tumor boundaries, external therapies often struggle to accurately locate the entire tumor, leading to decreased precision in hyperthermia. While current implantable hyperthermia devices can accurately locate and treat specific tumor areas, they still rely on external equipment for energy supply.

[0004] Therefore, there is an urgent need for a wirelessly rechargeable, wirelessly controllable, miniaturized, structurally designed, and biosafe thermotherapy device for postoperative treatment. Summary of the Invention

[0005] The purpose of this section is to outline some aspects of embodiments of the present invention and to briefly describe some preferred embodiments. Simplifications or omissions may be made in this section, as well as in the abstract and title of this application, to avoid obscuring the purpose of these documents; however, such simplifications or omissions should not be construed as limiting the scope of the invention.

[0006] In view of the problems existing in the above and / or prior art, the present invention is proposed.

[0007] Therefore, the purpose of this invention is to overcome the shortcomings of the prior art and provide a miniature implantable biosafety tumor hyperthermia device that can be wirelessly charged and wirelessly controlled.

[0008] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a miniature implantable biosafety tumor hyperthermia device that can be wirelessly charged and wirelessly controlled, characterized in that: the miniature implantable biosafety tumor hyperthermia device consists of four parts: a biosafety battery, a wireless charging module, a heating patch, and a magnetic control switch module.

[0009] As a preferred embodiment of the micro implantable biosafety tumor hyperthermia device of the present invention, the biosafety battery adopts a layered structure. In an inert gas glove box, the positive electrode, separator + electrolyte and negative electrode of the battery are stacked in a layered form and placed between two PP / PE films, and vacuum heat-sealed under external pressure.

[0010] As a preferred embodiment of the micro implantable biosafety tumor hyperthermia device of the present invention, the positive electrode of the battery is lithium iron phosphate, the negative electrode is a pre-lithiated lithium-tin alloy, and the electrolyte is 0.2 M LiBOB added to DMM solvent.

[0011] As a preferred embodiment of the miniature implantable biosafety tumor hyperthermia device of the present invention, the magnetic switch module includes a miniature magnetic reed switch, one end of which is connected to one pole of the battery, the other end of which is connected to one end of the heating patch, and the other pole of the battery is directly connected to the other end of the heating patch.

[0012] As a preferred embodiment of the miniature implantable biosafety tumor hyperthermia device of the present invention, wherein: the outer layer of the tumor hyperthermia device is covered with a PDMS film, and the components of each layer are tightly bonded together using thermosetting adhesive.

[0013] As a preferred embodiment of the miniature implantable biosafety tumor hyperthermia device of the present invention, the device is configured to be implanted together with the tumor after surgical removal, and then subjected to periodic and precise postoperative hyperthermia.

[0014] Another objective of this invention is to overcome the shortcomings of the prior art and provide a method for preparing a miniature implantable biosafety tumor hyperthermia device, characterized by comprising: Preparation of heating patches; Fabrication of a wireless charging module; Preparation of biosafe batteries; Connect the positive and negative terminals of the battery to the two ends of the wireless charging module, connect the miniature magnetic reed switch between the battery and the heating pad, and after the connection is completed, use thermosetting adhesive to tightly bond the components in the middle of each layer. Finally, cover the outer layer of the device with a PDMS film.

[0015] As a preferred embodiment of the preparation method described in this invention, the preparation method of the heating module includes: using additive manufacturing technology to print carbon nanotube slurry in a patterned manner on a polyimide substrate, and cutting out heating patches of appropriate size.

[0016] As a preferred embodiment of the preparation method described in this invention, the preparation method of the wireless charging module includes: using customized additive manufacturing technology, printing silver paste in the form of coils on a polyimide substrate, printing coils on both sides, connecting the positive and negative coils at the center, and finally connecting a micro circuit board for circuit integration.

[0017] In a preferred embodiment of the preparation method described in this invention, the resistance of the heating patch is 1500 ohms, and after being energized at 3.3V, the heating patch rises by a maximum of 7°C and an average of 6°C compared to the surrounding environment.

[0018] Beneficial effects of this invention: This invention develops an implantable wireless heating device. From a biosafety perspective, the device is fabricated using a series of safe materials; it utilizes a biosafety battery, coupled with a wireless charging module, to provide a long-term power supply; and it employs a customized heating module to uniformly and accurately raise the module temperature to the required level. The device is implanted after surgical removal of the tumor, followed by periodic, precise postoperative hyperthermia. Through a series of engineered designs, this device possesses the following advantages: wirelessly rechargeable power supply, wirelessly controllable switch, miniaturized structural design, biosafety, precise temperature supply, and precise regional treatment. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein: Figure 1 This is an optical photograph of the tumor hyperthermia device prepared in Example 2 of the present invention.

[0020] Figure 2 This is a schematic diagram of the tumor hyperthermia device in Embodiment 2 of the present invention.

[0021] Figure 3 The image shows the heating effect of the heating patch of Embodiment 2 of the present invention after being powered on (3.3V voltage) with parameters (air pressure 0.24MPa, moving speed 4mm / s).

[0022] Figure 4This is a data diagram showing the wireless charging device of Embodiment 2 of the present invention charging a lithium iron phosphate battery.

[0023] Figure 5 This is a diagram showing the effect of the tumor hyperthermia device after implantation and operation in Embodiment 2 of the present invention.

[0024] Figure 6 This is a flowchart of postoperative tumor treatment and treatment effect data (macroscopic MRI) of Embodiment 2 of the present invention using a tumor hyperthermia device.

[0025] Figure 7 Example 2 of the present invention illustrates the treatment results of using a tumor hyperthermia device in the form of tissue sections.

[0026] Figure 8 This is a heating patch prepared according to Embodiment 3 of the present invention. The heating effect of heating patches prepared with different parameters after being energized (3.3V voltage) is shown in the diagram, along with a simulated curve showing the relationship between the power passing through the patch and the temperature rise of the patch.

[0027] Figure 9 The simulated relationship curves of air pressure-temperature rise and moving speed-temperature rise during the preparation of the heating patch in Embodiment 3 of the present invention are intended to determine the relationship between different preparation parameters and temperature rise.

[0028] Figure 10 The results of TUNEL fluorescence staining are shown for the tumor hyperthermia device of the present invention.

[0029] Figure 11 These are the long-cycle test results of the battery of the tumor hyperthermia device of the present invention. Detailed Implementation

[0030] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the examples in the specification.

[0031] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0032] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0033] The raw materials used in this invention are as follows: Carbon nanotube slurry (conductive slurry) is widely available on the market. Its main components are a large amount of N-methylpyrrolidone and a small amount of carbon nanotube powder and its dispersant. In this experiment, the carbon nanotube slurry used was LB116-32 conductive agent from Duoduo Chemical, catalog number NE-000245. The carbon nanotube powder was CNT powder FT6120 from Duoduo Chemical, catalog number NE-000377. All other materials were commercially available. The 3D printing equipment was developed by the research group.

[0034] Example 1 This embodiment provides a miniature implantable biosafety tumor hyperthermia device that is wirelessly rechargeable and wirelessly controlled, such as... Figure 1 , 2 As shown, Figure 1 This is an optical photograph of the 3D printing equipment and tumor hyperthermia device in this embodiment.

[0035] Figure 2 This is a schematic diagram of the tumor hyperthermia device according to this embodiment. Wherein, Figure 2 (a) The component structure is shown in exploded view form, along with the circuit diagram of the component; like Figure 2 As shown in (b), the miniature implantable biosafety tumor hyperthermia device comprises four parts: a wireless charging module (100), a biosafety battery (200), a heating module (300), and a magnetic control switch module (400); The device is a flexible stacked structure, consisting of a heating module (300), a biosafety battery (200), a wireless charging module (100), and a magnetic switch module (400) in the interlayer gaps. The biosafety battery (200) adopts a layered structure. In an inert gas glove box, the positive electrode, separator + electrolyte, and negative electrode are stacked in a layered manner and placed between two PP / PE films. Under external pressure, the battery is vacuum heat-sealed. The positive electrode of the battery is lithium iron phosphate, the negative electrode is a pre-lithiated lithium-tin alloy, and the electrolyte is 0.2 M LiBOB added to DMM solvent; The magnetic switch module (400) includes a miniature magnetic reed switch, one end of which is connected to one pole of the battery, and the other end of which is connected to one end of the heating patch. The other pole of the battery is directly connected to the other end of the heating patch. The wireless charging module (100) is connected to the biosafety battery (200) to provide wireless power supply to the biosafety battery; The magnetic switch module (400) is connected in series between the biosafety battery (200) and the heating module (300) to realize wireless on / off control of the heating module without the need for external devices; The outer layer of the tumor hyperthermia device is covered with a PDMS film, and the components are tightly bonded together with thermosetting adhesive.

[0036] Example 2 This embodiment provides a method for preparing the wirelessly rechargeable and wirelessly controllable miniature implantable biosafety tumor hyperthermia device described in Embodiment 1, specifically including the following steps: (1) Preparation of heating patch: Using 3D printing equipment and a 24G dispensing needle, the parameters were adjusted to: air pressure 0.24MPa, moving speed 4mm / s, to uniformly print a customized pattern on a polyimide film. After drying, 13mm diameter circles were cut out to obtain the heating patch.

[0037] (2) Fabrication of the wireless charging module: Using 3D printing equipment and a 30G dispensing needle, with parameters adjusted to: air pressure 0.42MPa, moving speed 2mm / s, planar spiral coils were evenly printed on both sides of a polyimide film. After drying, 13mm diameter circular pieces were cut out. The coils from both sides were connected at the center, resulting in a coil inductance of approximately 0.8~1.2μH. Finally, the two ends of the coil were connected to a current integration circuit board (containing a 500nH resonant capacitor, a unidirectional diode, and a rectifier capacitor). This yields the wireless charging module.

[0038] (3) Preparation of biosafety batteries: Positive electrode preparation: Lithium iron phosphate, polyvinylidene fluoride, and carbon black were weighed at a mass ratio of 8:1:1, with a total weight of 1 g. An additional 1.7 mL of N-methylpyrrolidone was added as a dispersant solvent, and the mixture was ground to form a uniform slurry. This slurry was then coated onto a carbon cloth electrode and dried to serve as the positive electrode of the battery (square electrode, 10 mm * 10 mm).

[0039] Negative electrode preparation: Tin powder, polyvinylidene fluoride, and carbon black were mixed (mass ratio 7:1.5:1.5, total mass 1g), and an additional 2.75mL of N-methylpyrrolidone was added and ground to form a uniform tin paste. This paste was then applied to a carbon cloth electrode and dried (square current collector electrode, size 10mm*10mm).

[0040] After drying, tin paste is printed onto the current collector to prepare an electrode sheet loaded with metallic tin. The electrode sheet loaded with metallic tin is assembled with a lithium metal electrode sheet to form a lithium / tin battery. The lithium / tin battery is discharged to 0.01V. After discharge, the lithium / tin battery is transferred to an argon glove box, the tin electrode sheet is removed and cleaned. This electrode sheet is the lithium-tin alloy negative electrode sheet.

[0041] Inside an inert gas glove box, the prepared lithium iron phosphate cathode, separator, and pre-lithiated lithium-tin alloy anode are stacked in layers and placed between two PP / PE films (serving as the encapsulation shell). A heat sealer is used to seal three sides first, then 50 μL of DMM electrolyte is injected. The pre-encapsulated battery is placed in a battery clamp and pressure is applied. Vacuum pre-encapsulation is performed first to remove excess electrolyte and gas, and finally, it is encapsulated again. This yields a flexible battery.

[0042] (4) Preparation of postoperative tumor hyperthermia devices: First, connect the positive and negative terminals of the battery to the two ends of the wireless charging module. After testing for continuity, connect one end of a miniature magnetic reed switch to one terminal of the battery, and the other end of the reed switch to one end of the heating pad. Connect the other terminal of the battery directly to the other end of the heating pad, ensuring the entire circuit is connected.

[0043] After the connection is completed, thermosetting adhesive is used to tightly bond the components in the middle of each layer. Finally, a PDMS film is covered on the outer layer of the device to prepare a postoperative tumor hyperthermia device.

[0044] Figure 3 This image shows the heating effect of the heating patch of Embodiment 2 of the present invention after being powered on (3.3V), with parameters (air pressure 0.24MPa, moving speed 4mm / s). Since the window temperature for tumor hyperthermia is approximately 43 degrees Celsius, the heating patch needs to raise the temperature by 6°C within the body (37°C). To meet this heating requirement, the heating patch was custom-designed with customized parameters. The prepared heating patch has a resistance of 1500 ohms, and the platform voltage provided by a single lithium iron phosphate battery is 3.3V. At this voltage, the heating patch raises the temperature by a maximum of 7°C and an average of 6°C compared to the surrounding environment, precisely matching this heating treatment window. (Scale bar is 3mm) Figure 4 This is a data graph showing the charging of a lithium iron phosphate battery using the wireless charging device of Embodiment 2 of the present invention. The distance between the transmitter and receiver is 4mm, the battery discharge current is constant at 0.3mA, and the battery voltage reaches approximately 3.83V after 5.5 hours of wireless charging. Afterward, it can be discharged at a constant current of 0.3mA for about 5 hours. The charge / discharge voltage curve remains stable and regular, indicating the stability of the wireless charging module.

[0045] Figure 5This is Example 2 of the present invention, showing the postoperative tumor treatment flowchart and treatment effect data (macroscopic MRI) of using a tumor hyperthermia device. First, the tumor model was constructed by subcutaneously injecting gliomas into mice. After seven days of growth, a glioma model was successfully established. The first MRI image on the left in the figure represents the tumor-free control group, while the second image clearly shows the presence of the tumor, indicating successful model construction. The tumor was surgically removed to establish the postoperative mouse model. The third MRI image on the left shows that the tumor has been macroscopically removed. However, microscopically, tumor cells may still be infiltrating normal tissue, and these residual tumor tissues may cause tumor recurrence. Simultaneously with the removal, the device was precisely attached to the residual tumor tissue. After suturing, hyperthermia was performed for 30 minutes daily for 14 consecutive days (wirelessly controlled via a magnetic switch). After hyperthermia, the device was removed, and a 10-day recovery period was allowed. The final MRI results show that the untreated mice experienced secondary tumor recurrence (first image on the right), while the treated mice showed no macroscopic tumor recurrence (second image on the right). This indicates that hyperthermia was macroscopically effective. (The scale bar on the MRI image is 1cm) Figure 6 This is a diagram illustrating the effect of the tumor hyperthermia device after implantation and operation, as shown in Embodiment 2 of the present invention. In vitro infrared thermography shows that the mouse's skin temperature reached a maximum of approximately 42°C, indicating that the device successfully heated and operated in vivo.

[0046] Figure 7 Example 2 of this invention illustrates the treatment results of using a tumor hyperthermia device in the form of tissue sections. The control group on the right shows HE sections of untreated mice and KI-67 fluorescent staining below. The HE sections show at least two sites of secondary tumor recurrence, indicating that the malignant tumors not only recurred but also metastasized. Furthermore, HE staining can reveal inflammatory responses. Poor biocompatibility of the device can cause inflammatory reactions in the tissue, with a large accumulation of inflammatory cells and thick fibrous capsules repelling the device. The HE staining shows that the device did not induce an inflammatory response in the tissue. This is due to the excellent biocompatibility of the outer PDMS layer of the device and the tightness of the device packaging, preventing leakage.

[0047] The high signal intensity of KI-67 fluorescence staining indicates the presence of a tumor. However, the control group (HE and KI-67 sections on the left) showed no significant tumor growth, indicating effective tumor removal at the microscopic level. These results demonstrate the device's effectiveness in treating postoperative tumor recurrence. (Scale bar: 200 μm) Example 3 The difference between this embodiment and Embodiment 2 is that the printing parameters in step (1) are adjusted: the air pressure is 0.18 MPa and the moving speed is 6 mm / s; a heating patch with a resistance of approximately 2.5 kΩ is prepared. Alternatively, the printing parameters are adjusted: the air pressure is 0.18 MPa and the moving speed is 4 mm / s; a heating patch with a resistance of approximately 1.5 kΩ is prepared. All other steps are the same as in Embodiment 2, resulting in heating modules and postoperative tumor hyperthermia devices with two different printing parameters.

[0048] Figure 8 This is a heating patch prepared according to Embodiment 3 of the present invention. The heating effect of heating patches prepared with different parameters after being energized (3.3V voltage) is shown in the graph, along with a simulated curve showing the relationship between the power passing through the patch and the temperature rise. It can be seen that after changing the preparation parameters of the heating patch, the temperature rise varies after the patch is connected to a lithium iron phosphate battery (providing a 3.3V platform voltage). The heating effects of the two heating patches on the left illustrate that heating patches that do not conform to customized parameters are unlikely to reach the required therapeutic window temperature. Therefore, the preparation parameters and the energizing voltage were changed multiple times to alter the power passing through the heating patch, resulting in corresponding temperature rise values, and a power-temperature rise curve was plotted. It can be seen that to achieve a 6°C increase in the therapeutic window, the power range through the heating patch is 10~20mW. This greatly clarifies the preparation conditions of the heating patch.

[0049] Figure 9 The simulated relationship curves of air pressure-temperature rise and moving speed-temperature rise during the preparation of the heating patch in Embodiment 3 of the present invention aim to determine the relationship between different preparation parameters and temperature rise. The following effect can be obtained from the relationship: to prepare a patch at a specific heating temperature, the specific preparation parameters can be directly obtained from the curve, thereby quickly and accurately adjusting the parameters to prepare the product.

[0050] Figure 10 The results of TUNEL fluorescence staining of the tumor hyperthermia device prepared in Example 2 of this invention are shown. TUNEL fluorescence staining can effectively detect cell death caused by tissue necrosis and apoptosis, and is often used to evaluate the degree of tissue damage. No obvious abnormalities were observed in the TUNEL fluorescence staining of the treatment group.

[0051] Figure 11 The long-cycle test of the biosafety battery of the tumor hyperthermia device prepared in Example 2 of the present invention was conducted under the condition of 0.2C.

[0052] Existing hyperthermia techniques, including microwave ablation, radiofrequency heating, laser interstitial hyperthermia, and magnetothermal therapy, have all demonstrated the effectiveness of local heating. However, these methods typically employ intermittent interventions, relying on external energy delivery, repeated targeted treatments, or short treatment cycles. For example, radiofrequency heating and laser interstitial hyperthermia both require external devices to deliver energy, posing a risk of infection; microwave ablation and magnetothermal therapy usually require large external equipment, which is not only expensive and requires regular treatment cycles, but also makes it difficult to accurately locate and control the temperature of irregularly invasive malignant tumors such as gliomas, hindering precise tumor treatment. The wireless rechargeable electrothermal device prepared in this invention can not only precisely control the hyperthermia temperature (43 degrees Celsius) but also wirelessly deliver energy to maintain the device's long-term use without the need for external devices. After tumor resection, the device is implanted and attached, allowing for targeted hyperthermia treatment of the attached area.

[0053] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the present invention.

Claims

1. A miniature implantable biosafety tumor hyperthermia device that is wirelessly rechargeable and wirelessly controlled, characterized in that: The micro implantable biosafety tumor hyperthermia device consists of four parts: a wireless charging module (100), a biosafety battery (200), a heating module (300), and a magnetic control switch module (400). The device is a flexible stacked structure, consisting of a heating module (300), a biosafety battery (200), a wireless charging module (100), and a magnetic switch module (400) in the interlayer gaps. The wireless charging module (100) is connected to the biosafety battery (200) to provide wireless power supply to the biosafety battery; The magnetic switch module (400) is connected in series between the biosafety battery (200) and the heating module (300) to realize wireless on / off control of the heating module without the need for external devices; The components of the device are tightly bonded together with thermosetting adhesive, and the outer layer is covered with a polydimethylsiloxane (PDMS) film to achieve biosafety encapsulation.

2. The miniature implantable biosafety tumor hyperthermia device as described in claim 1, characterized in that: The biosafety battery (200) adopts a layered structure. In an inert gas glove box, the positive electrode, separator + electrolyte and negative electrode are stacked in a layered form and placed between two PP / PE films. Under external pressure, the battery is vacuum heat-sealed.

3. The miniature implantable biosafety tumor hyperthermia device as described in claim 1, characterized in that: The positive electrode of the battery is lithium iron phosphate, the negative electrode is a pre-lithiated lithium-tin alloy, and the electrolyte is 0.2 M LiBOB added to DMM solvent.

4. The miniature implantable biosafety tumor hyperthermia device as described in claim 1, characterized in that: The magnetic switch module (400) includes a miniature magnetic reed switch, one end of which is connected to one pole of the battery, and the other end of which is connected to one end of the heating patch. The other pole of the battery is directly connected to the other end of the heating patch.

5. The miniature implantable biosafety tumor hyperthermia device as described in claim 1, characterized in that: The heating module (300) is a carbon nanotube heating patch, which is made by patterning carbon nanotube slurry onto a polyimide substrate using additive manufacturing technology. The heating patch has a resistance of 1500 ohms and, at a working voltage of 3.3V, its temperature rises by an average of 6°C and a maximum of 7°C compared to the surrounding environment.

6. The method for preparing the miniature implantable biosafety tumor hyperthermia device according to any one of claims 1 to 5, characterized in that: include, Preparation of heating module; Fabrication of a wireless charging module; Preparation of biosafe batteries; Connect the positive and negative terminals of the battery to the two ends of the wireless charging module, connect the miniature magnetic reed switch between the battery and the heating pad, and after the connection is completed, use thermosetting adhesive to tightly bond the components in the middle of each layer. Finally, cover the outer layer of the device with a PDMS film.

7. The preparation method according to claim 6, characterized in that: The method for preparing the heating module includes: using additive manufacturing technology to print carbon nanotube slurry in a patterned manner on a polyimide substrate, and cutting out heating patches of appropriate size.

8. The preparation method according to claim 6, characterized in that: The method for preparing the wireless charging module includes: using customized additive manufacturing technology, printing silver paste in the form of coils on a polyimide substrate, printing coils on both sides, connecting the positive and negative coils at the center, and finally connecting a micro circuit board for circuit integration.

9. The preparation method according to claim 7, characterized in that: The heating patch has a resistance of 1500 ohms. When powered on at 3.3V, the heating patch rises by a maximum of 7°C and an average of 6°C compared to the surrounding environment.

10. The application of the miniature implantable biosafety tumor hyperthermia device as described in any one of claims 1 to 5.

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