Split type deep body temperature monitoring device, preparation method and application

Abstract

The application discloses a split type deep body temperature monitoring device, a preparation method and application, and belongs to the technical field of temperature monitoring. The monitoring device is prepared from biodegradable materials and comprises a double-layer electrode layer, a spacing layer, a connecting channel, a dielectric layer and a packaging layer. Each of the upper and lower electrode layers comprises a spiral inductance coil, a serpentine connecting wire and a capacitor plate. The spiral inductance coils are arranged on the two sides of the spacing layer and have opposite rotation directions, and are connected in series through the connecting channel to enhance mutual inductance. The serpentine connecting wire is used for connecting the spiral inductance coil and the capacitor plate, and improves mechanical flexibility. The application adopts a split type design, better realizes deep body temperature monitoring, and significantly improves a wireless reading distance and a Q value in cooperation with series-connected double-layer asymmetric coils, so that the accuracy of deep body temperature monitoring is comprehensively improved. Moreover, the sensor is made of fully biodegradable materials, secondary surgery for removal is avoided, and has a good biomedical application prospect.

Description

Technical Field

[0001] This invention relates to the field of temperature monitoring technology, specifically to a split-type deep body temperature monitoring device, its preparation method, and its application. Background Technology

[0002] Wireless passive LC resonant sensors achieve wireless detection of physical parameters by utilizing changes in the resonant characteristics of an inductor-capacitor circuit. They offer advantages such as no power supply required, simple structure, and ease of packaging, making them promising for applications in temperature and other parameter monitoring. However, existing wireless passive LC resonant sensors generally suffer from insufficient electromagnetic coupling, resulting in short readout distances and low resonance quality factors, making it difficult to obtain stable and accurate measurement results in confined or implanted environments. This is particularly true when used for deep body temperature monitoring, where the increased distance from the external reading device further reduces the accuracy of the measurement results. Therefore, existing wireless passive LC resonant sensors limit their practical application in biomedical and other scenarios. Summary of the Invention

[0003] Based on the above-mentioned technical problems, the present invention proposes a split-type deep body temperature monitoring device, as well as the preparation method and application of the split-type deep body temperature monitoring device.

[0004] The technical solution adopted in this invention is:

[0005] A split-type deep body temperature monitoring device includes an electrode layer, a spacer layer, a dielectric layer and an encapsulation layer. The electrode layer includes a first electrode layer and a second electrode layer, which are stacked together. The spacer layer and the dielectric layer are disposed between the first electrode layer and the second electrode layer.

[0006] The first electrode layer includes a first spiral inductor coil, a first connecting line, and a first capacitor plate, wherein the first spiral inductor coil is connected to the first capacitor plate via the first connecting line; the second electrode layer includes a second spiral inductor coil, a second connecting line, and a second capacitor plate, wherein the second spiral inductor coil is connected to the second capacitor plate via the second connecting line.

[0007] The spacer layer includes a circular sheet and a strip sheet. The circular sheet is disposed between the first spiral inductor and the second spiral inductor, and a conductive region is provided at the center of the circular sheet. The spiral directions of the first spiral inductor and the second spiral inductor are opposite, and the inner end of the first spiral inductor is electrically connected to the inner end of the second spiral inductor through the conductive region. The strip sheet is disposed between the first connecting line and the second connecting line.

[0008] The dielectric layer is made of a temperature-sensitive material and is disposed between the first capacitor plate and the second capacitor plate. The first capacitor plate, the dielectric layer and the second capacitor plate together constitute a parallel plate capacitor structure.

[0009] The encapsulation layer covers the outside of the electrode layer, spacer layer, and dielectric layer.

[0010] The present invention also provides a method for preparing the split-type deep body temperature monitoring device as described above, comprising the following steps:

[0011] (1) Preparation of electrode layers: The first electrode layer and the second electrode layer are fabricated on a biodegradable conductive substrate, respectively;

[0012] (2) Preparation of spacer layer and connection channel: Prepare a biodegradable polymer film as spacer layer, and open through holes in the film and fill them with conductive material to form connection channel;

[0013] (3) Fabrication of dielectric layer: The dielectric layer is fabricated using a temperature-sensitive material;

[0014] (4) Assembly and lamination: Align and stack the first electrode layer, spacer layer and second electrode layer, so that the first spiral inductor coil and the second spiral inductor coil are connected through the connection channel, the first capacitor plate and the second capacitor plate sandwich the dielectric layer and are combined by hot pressing process;

[0015] (5) Encapsulation: The assembled device is fully encapsulated using a biodegradable polymer film to obtain a split-type deep body temperature monitoring device.

[0016] The present invention also provides an application of the split-type deep body temperature monitoring device as described above. The monitoring device is used for temperature monitoring at deep body locations. In use, the ends of the first and second capacitor plates of the electrode layer are inserted into the deep body location to be measured, and the ends of the first and second spiral inductor coils of the electrode layer are placed below the body surface to cooperate with external reading devices.

[0017] The beneficial technical effects of the present invention are as follows:

[0018] (1) The monitoring device of the present invention adopts a split design, which separates the temperature-sensitive unit (capacitor) and the transmitting unit (inductor) and connects them through a connecting line, thereby enabling the monitoring of temperature information deep in the body and shortening the distance between the spiral inductor coil and the external reading device, making it convenient for the external reading device to read information and improving the accuracy of temperature measurement results.

[0019] (2) The present invention adopts a double-layer inductor coil design, and the spiral directions of the upper and lower spiral inductor coils are opposite. The inner ring of the spiral inductor coil is electrically connected through a connecting channel to increase the coupling ability with the reading coil, increase the reading distance, improve the Q value of the sensor, and further improve the accuracy of the temperature measurement results.

[0020] (3) The connecting wires in the monitoring device of the present invention adopt a serpentine structure design, which significantly improves the mechanical reliability and fatigue resistance of the device in the dynamic environment in vivo; moreover, the serpentine connecting wires adopt an upper and lower layer staggered design, which reduces the risk of accidental contact and avoids the introduction of additional parasitic capacitance.

[0021] (4) The capacitor plates in the monitoring device of the present invention adopt various shapes, which can better adapt to the irregular organ surface, increase the friction with biological tissue, and prevent the monitoring device from shifting in the body.

[0022] (5) The monitoring device of the present invention is made of fully biodegradable materials, such as the spacer layer and the encapsulation layer made of polylactic acid-glycolic acid copolymer, and the dielectric layer made of polyethylene glycol. After being implanted in the body, it does not need to be removed by a second surgery, which greatly reduces the risk of infection and has broad application prospects. Attached Figure Description

[0023] Figure 1 This is a schematic diagram illustrating the structural principle of the split-type deep body temperature monitoring device of the present invention;

[0024] Figure 2 for Figure 1 A schematic diagram of the structural principle without the encapsulation layer;

[0025] Figure 3 This is a top view of the first electrode layer and the second electrode layer stacked in the monitoring device of the present invention;

[0026] Figure 4 The diagram shows the structure of capacitor plates of different shapes in the monitoring device of the present invention; wherein, (1) is a circular capacitor plate, (2) is a hexagonal capacitor plate, (3) is a square capacitor plate, (4) is an elliptical capacitor plate, (5) is a forked capacitor plate, and (6) is a petal-shaped capacitor plate.

[0027] Figure 5 The equivalent circuit diagram for deep body temperature monitoring using the monitoring device of the present invention;

[0028] Figure 6 This is a simulation data diagram of the monitoring device of the present invention; wherein, (a) shows the return loss (S) of the monitoring device at different coupling distances. 11 (a) shows the frequency response characteristics of the monitoring device at different temperatures (35℃~42℃). (b) shows the frequency response characteristics of the monitoring device at different temperatures (35℃~42℃).

[0029] In the diagram: 1-spacer layer, 2-dielectric layer, 3-encapsulation layer, 4-first electrode layer, 5-second electrode layer;

[0030] 101-Circular sheet, 102-Strip sheet, 103-Circular through hole, 104-Circular conductive material, 401-First spiral inductor coil, 402-First connecting wire, 403-First capacitor plate, 501-Second spiral inductor coil, 502-Second connecting wire, 503-Second capacitor plate. Detailed Implementation

[0031] This invention discloses a split-type deep body temperature monitoring device, its preparation method, and its application. The monitoring device, or sensor, is made of biodegradable materials and includes a double-layer electrode layer, a spacer layer, a connecting channel, a dielectric layer, and an encapsulation layer. Each of the upper and lower electrode layers contains a spiral inductor coil, a serpentine connecting wire, and a capacitor plate. The spiral inductor coil is positioned on both sides of the spacer layer with an asymmetrical helix direction and is connected in series through the connecting channel to enhance mutual inductance. The serpentine connecting wire connects the spiral inductor coil to the capacitor plate, improving mechanical flexibility. The irregularly shaped capacitor plate increases friction with tissue. This invention employs a split-type design, which effectively achieves deep body temperature monitoring. The series-connected double-layer asymmetrical coil significantly improves the wireless reading distance and Q value, thereby comprehensively improving the accuracy of deep body temperature monitoring. Furthermore, the sensor of this invention is made of fully biodegradable materials, avoiding the need for secondary surgery for removal, and has promising prospects for biomedical applications.

[0032] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0033] Example 1: As Figure 1 As shown, a split-type deep body temperature monitoring device includes an electrode layer, a spacer layer 1, a dielectric layer 2, and an encapsulation layer 3. The electrode layer includes a first electrode layer 4 and a second electrode layer 5, which are stacked. The spacer layer 1 and the dielectric layer 2 are disposed between the first electrode layer 4 and the second electrode layer 5. The first electrode layer 4 includes a first spiral inductor coil 401, a first connecting line 402, and a first capacitor plate 403. The first spiral inductor coil 401 is connected to the first capacitor plate 403 via the first connecting line 402. The second electrode layer 5 includes a second spiral inductor coil 501, a second connecting line 502, and a second capacitor plate 503. The second spiral inductor coil 501 is connected to the second capacitor plate 503 via the second connecting line 502.

[0034] The spacer layer 1 includes a circular sheet 101 and a strip-shaped sheet 102. The circular sheet 101 is disposed between the first spiral inductor coil 401 and the second spiral inductor coil 501, and a conductive region is provided at the center of the circular sheet 101. The spiral directions of the first spiral inductor coil 401 and the second spiral inductor coil 501 are opposite, such as... Figure 1 and Figure 2 As shown, the first spiral inductor coil 401 is counterclockwise spiraled, and the second spiral inductor coil 501 is clockwise spiraled to enhance inductance and coupling coefficient. A circular through-hole 103 is provided in the conductive area of ​​the circular sheet layer 101, and a circular sheet-shaped conductive material 104 is filled in the circular through-hole 103 to form a connection channel. The inner end of the first spiral inductor coil 401 is electrically connected to the inner end of the second spiral inductor coil 501 through the circular sheet-shaped conductive material 104. This design ensures that the magnetic field generated when the current flows through the upper and lower inductor coils is in the same direction, thereby achieving a superposition effect through mutual inductance (…). This significantly improves the total inductance and quality factor (Q value). The strip-shaped layer 102 is disposed between the first connecting line 402 and the second connecting line 502. The dielectric layer 2 is made of a temperature-sensitive material and is disposed between the first capacitor plate 403 and the second capacitor plate 503. The first capacitor plate 403, the dielectric layer 2, and the second capacitor plate 503 together constitute a parallel plate capacitor structure. The encapsulation layer 3 is disposed outside the electrode layers, etc., and seals and encapsulates the first electrode layer 4, the second electrode layer 5, the spacer layer 1, and the dielectric layer 2. The encapsulation layer 3 serves to physically isolate the device from bodily fluids, preventing rapid degradation or short circuits, while ensuring biocompatibility.

[0035] The monitoring device is used for temperature monitoring at deep locations within the body. In use, the ends of the first capacitor plate 403 and the second capacitor plate 503 of the electrode layer are inserted into the deep location to be measured within the body, and the ends of the first spiral inductor coil 401 and the second spiral inductor coil 501 of the electrode layer are placed below the surface of the body to cooperate with external reading devices.

[0036] This invention's monitoring device employs a split design, separating the temperature monitoring end from the information transmitting end and connecting them via a connecting cable. This enables the monitoring of temperature information deep within the body and shortens the distance between the spiral inductor coil and the external reading device, facilitating information reading and improving the accuracy of temperature measurement results. Furthermore, this invention utilizes a double-layer inductor coil design, with the upper and lower spiral inductor coils having opposite helical directions (counter-clockwise and clockwise respectively). The inner coils of the spiral inductor coils are electrically connected in series via a connecting channel to increase coupling with the reading coil, extend the reading distance, improve the sensor's Q value, and further enhance the accuracy of temperature measurement results.

[0037] Example 2: Based on Example 1, the following design is also made: Figure 1 , Figure 2 As shown, both the first connecting line 402 and the second connecting line 502 are serpentine curves, specifically derived from function expressions. The resulting curves are formed by connecting them end to end. The line width of the serpentine curve is 0.5mm. One end of the first connecting line 402 is connected to the outer end of the first spiral inductor coil 401, and the other end of the first connecting line 402 is connected to the first capacitor plate 403; one end of the second connecting line 502 is connected to the outer end of the second spiral inductor coil 501, and the other end of the second connecting line 502 is connected to the second capacitor plate 503. Furthermore, the first connecting line 402 and the second connecting line 502 are arranged in an alternating vertical arrangement, as shown below. Figure 3 As shown, the staggered distance when projected onto the same horizontal plane is 0.5mm.

[0038] The first connecting line 402 and the second connecting line 502 adopt a serpentine curve structure, which has excellent mechanical ductility. This structure can effectively release the mechanical stress generated by the continuous dynamic deformation of organs (such as heartbeat, gastrointestinal peristalsis, and muscle contraction) after the device is implanted in the body, prevent electrode breakage, and improve fatigue resistance. The serpentine connecting lines adopt an alternating upper and lower layer design, which reduces the risk of accidental contact and avoids the introduction of additional parasitic capacitance.

[0039] The first spiral inductor coil 401 and the second spiral inductor coil 501 have a line width of less than or equal to 0.5 mm, a number of turns of less than or equal to 20, and a thickness of less than or equal to 0.1 mm. The thickness of both the spacer layer 1 and the dielectric layer 2 is less than or equal to 10 mm. The overall size of the monitoring device is less than or equal to 100 mm to meet the requirements of minimally invasive implantation.

[0040] like Figure 4 As shown, the shapes of the first capacitor plate 403 and the second capacitor plate 503 are selected from one of the following: circular, hexagonal, square, elliptical, forked, and petal-shaped. Among them, the forked and petal shapes, which have complex edges, can increase the contact friction with biological tissue after implantation, playing a role in physical anchoring. They are particularly suitable for the surfaces of irregular or frequently peristaltic organs such as the heart and intestines, preventing the sensor from shifting on the slippery and dynamic tissue surfaces in the body.

[0041] Example 3: Based on Example 2, the following design is further implemented: The electrode layers, namely the first electrode layer 4 and the second electrode layer 5, are selected from magnesium, zinc, and iron. These metals have good conductivity and are essential trace elements for the human body, and their degradation products are non-toxic. The spacer layer 1 is made of polylactic acid-glycolic acid copolymer (PLGA), which serves as a supporting framework to ensure the spacing between the upper and lower inductor coils. The degradation rate can also be controlled by adjusting the ratio of lactic acid to glycolic acid. The dielectric layer 2 is made of polyethylene glycol (PEG), utilizing its dielectric properties within a specific temperature range to achieve temperature sensing. The encapsulation layer 3 is made of polylactic acid-glycolic acid copolymer (PLGA), providing both good sealing and biodegradability. The conductive material filling the through-holes is a tungsten wax mixture, made by mixing tungsten powder and candelilla wax. The tungsten powder provides conductivity, while the wax matrix provides plasticity and biodegradability.

[0042] The working principle of the split-type deep body temperature monitoring device of this invention is roughly as follows:

[0043] This invention operates based on the principle of LC resonant circuits. For example... Figure 5 As shown in the equivalent circuit diagram, the equivalent circuit of the monitoring device (sensor) includes inductors L1 and L2 connected in series (corresponding to the upper and lower spiral inductors, namely the first spiral inductor 401 and the second spiral inductor 501, respectively), resistor R1, and a variable capacitor composed of capacitor plates and a dielectric layer. Its resonant frequency The calculation formula is:

[0044]

[0045] in, For the total equivalent inductance, It is a variable capacitor.

[0046] When the ambient temperature changes, the dielectric constant of dielectric layer 2 ( The capacitance will change, which in turn will affect the capacitance. The value changes (according to) Changes in capacitance directly affect the sensor's resonant frequency. Drift. This is determined by an external reading device (containing a reading coil). and resistance Transmit a frequency sweep signal, utilizing electromagnetic coupling (mutual inductance) , Monitor the signal reflected back from the sensor and detect the shift in its resonant frequency (usually manifested as return loss). By observing the movement of the trough position of the curve, the temperature information of the measured part can be deduced.

[0047] Example 4:

[0048] This invention also provides a method for preparing a split-type deep body temperature monitoring device, specifically including the following steps:

[0049] Step S1: Prepare the electrode layer;

[0050] A 100μm thick biodegradable magnesium (Mg) foil was selected as the conductive layer substrate and ultrasonically cleaned with deionized water for 5 minutes each time to remove surface oil and impurities.

[0051] The cutting is performed using a small ultraviolet laser cutting machine. The preferred parameters are: working current of 12A, Q drive frequency of 60kHz, Q drive pulse width of 9μs, cutting speed of 600mm / s, and processing times of 1000 times.

[0052] Finally, the material is rinsed with deionized water and then dried to obtain the upper first electrode layer and the lower second electrode layer.

[0053] Step S2: Prepare the spacer layer and connecting channels;

[0054] Preparation of PLGA solution: Weigh polylactic acid-glycolic acid copolymer (PLGA, with a molar ratio of lactic acid to glycolic acid of 50:50 and a molecular weight of 5w) particles, dissolve them in dichloromethane (DCM) solvent, and prepare a PLGA solution with a mass fraction of 15wt%.

[0055] Thin film preparation: The above solution was coated onto a clean glass substrate by casting, and then placed in a vacuum drying oven and dried at room temperature for 24 hours to remove the solvent, thus obtaining a PLGA spacer layer film with a thickness of about 80 μm.

[0056] Drilling: A 6mm diameter through hole is made at the preset center position of the PLGA spacer film using an ultraviolet laser cutting machine.

[0057] Filling the connection channels: Weigh tungsten powder (particle size 1-5μm) and small wax resin, and mix them at a mass ratio of 8:2. Heat the mixture to 90℃ to melt it and stir it evenly. While it is hot, fill it into the through-holes of the above PLGA film. After cooling and solidification, conductive connection channels are formed.

[0058] Step S3: Prepare the dielectric layer;

[0059] Polyethylene glycol (PEG) with a molecular weight of 1500 was selected as the temperature-sensitive dielectric material. The PEG was heated to 65°C to melt and then coated onto the capacitor plate area of ​​the second electrode layer by spin coating at a speed of 1000 rpm. After cooling, a uniform dielectric layer with a thickness of approximately 500 μm was formed.

[0060] Step S4: Device assembly and lamination;

[0061] Alignment and assembly were performed with the aid of a stereomicroscope. The second electrode layer, spacer layer, and first electrode layer were stacked sequentially, ensuring:

[0062] The inner ends of the first and second spiral inductors are accurately aligned with the tungsten wax connection channel in the middle; the first and second capacitor plates are accurately aligned, and the PEG dielectric layer prepared in step S3 is sandwiched in the middle. The stacked device is placed in a hot press, and the temperature is set to 60°C (slightly higher than the glass transition temperature of PLGA but lower than its melting point), the pressure is 0.5 MPa, and the holding time is 3 minutes, so that the layers are tightly bonded to form an integrated structure.

[0063] Step S5: Packaging;

[0064] Two PLGA films (approximately 50 μm thick), slightly larger than the sensor body, are cut and placed on the top and bottom of the assembled device, respectively. A thermoforming machine is used to heat and encapsulate only the edge areas of the device, set at 70°C, 1 MPa, and 2 minutes, fusing the edges of the upper and lower encapsulation layers to complete the full encapsulation of the sensor. Finally, laser cutting is used to trim any excess edges, resulting in the finished sensor, i.e., the split-type deep body temperature monitoring device.

[0065] Performance simulation and analysis:

[0066] Figure 6 Simulation test results of the sensor of the present invention are presented. Among them, (a) shows the return loss S of the sensor at different coupling distances. 11 The curve shows that the double-layer inductor structure used in this invention can maintain a deep resonance valley (Dip) even at a long read distance, demonstrating its excellent coupling ability and high Q value.

[0067] (b) shows the frequency response characteristics of the sensor at different temperatures (35℃~42℃). As the temperature increases, the resonant frequency shifts significantly (the peak of the curve in the figure shifts to the left / lower frequency direction). This indicates that the sensor has good sensitivity and linearity to changes in physiological body temperature, and can meet the needs of core body temperature monitoring (36℃~38℃) and fever monitoring.

[0068] In summary, this invention, through the separate design of the spiral inductor coil and capacitor plate, the double-layer asymmetric spiral inductor design, the serpentine flexible interconnection, and the combination of biodegradable materials, successfully solves the problems of short wireless transmission distance, inability to perform deep body temperature monitoring, and the need for secondary surgery to remove existing implantable sensors, and has important clinical application value.

[0069] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. An application of a split-type deep body temperature monitoring device, characterized in that: This split-type deep body temperature monitoring device is used for temperature monitoring at deep locations within the body. The split-type deep body temperature monitoring device includes an electrode layer, a spacer layer, a dielectric layer and an encapsulation layer. The electrode layer includes a first electrode layer and a second electrode layer, which are stacked together. The spacer layer and the dielectric layer are disposed between the first electrode layer and the second electrode layer. The first electrode layer includes a first spiral inductor coil, a first connecting line, and a first capacitor plate, wherein the first spiral inductor coil is connected to the first capacitor plate via the first connecting line; the second electrode layer includes a second spiral inductor coil, a second connecting line, and a second capacitor plate, wherein the second spiral inductor coil is connected to the second capacitor plate via the second connecting line. The spacer layer includes a circular sheet and a strip sheet. The circular sheet is disposed between the first spiral inductor and the second spiral inductor, and a conductive region is provided at the center of the circular sheet. The spiral directions of the first spiral inductor and the second spiral inductor are opposite, and the inner end of the first spiral inductor is electrically connected to the inner end of the second spiral inductor through the conductive region. The strip sheet is disposed between the first connecting line and the second connecting line. The dielectric layer is made of a temperature-sensitive material and is disposed between the first capacitor plate and the second capacitor plate. The first capacitor plate, the dielectric layer and the second capacitor plate together constitute a parallel plate capacitor structure. The encapsulation layer covers the outside of the electrode layer, the spacer layer, and the dielectric layer; Both the first connecting line and the second connecting line are serpentine curves; and the first connecting line and the second connecting line are arranged in an alternating manner, with an alternation distance of 0.3-0.5mm when projected onto the same horizontal plane; The first spiral inductor coil is counterclockwise spiraled, and the second spiral inductor coil is clockwise spiraled; through holes are provided in the conductive area of ​​the circular sheet, and conductive material is filled in the through holes to form a connection channel; The shapes of the first capacitor plate and the second capacitor plate are selected from one of the following: circular, hexagonal, square, elliptical, forked, and petal-shaped. The conductive material filling the through hole is a tungsten wax mixture, which is made by mixing tungsten powder and candelilla wax. In use, the ends of the first and second capacitor plates of the electrode layer are inserted into the deep part of the body at the location to be measured, and the ends of the first and second spiral inductors of the electrode layer are placed below the surface of the body to cooperate with external reading devices.

2. The application of the split-type deep body temperature monitoring device according to claim 1, characterized in that: The line width of the first spiral inductor and the second spiral inductor is less than or equal to 0.5 mm, the number of turns is less than or equal to 20, and the thickness is less than or equal to 0.1 mm. The thickness of both the spacer layer and the dielectric layer is less than or equal to 10 mm; The overall size of the monitoring device is less than or equal to 100 mm.

3. The application of the split-type deep body temperature monitoring device according to claim 1, characterized in that, The preparation method of this split-type deep body temperature monitoring device includes the following steps: (1) Preparation of electrode layers: The first electrode layer and the second electrode layer are fabricated on a biodegradable conductive substrate, respectively; (2) Preparation of spacer layer and connection channel: Prepare a biodegradable polymer film as spacer layer, and open through holes in the film and fill them with conductive material to form connection channel; (3) Fabrication of dielectric layer: The dielectric layer is fabricated using a temperature-sensitive material; (4) Assembly and lamination: Align and stack the first electrode layer, spacer layer and second electrode layer, so that the first spiral inductor coil and the second spiral inductor coil are connected through the connection channel, the first capacitor plate and the second capacitor plate sandwich the dielectric layer and are combined by hot pressing process; (5) Encapsulation: The assembled device is fully encapsulated using a biodegradable polymer film to obtain a split-type deep body temperature monitoring device.

4. The application of the split-type deep body temperature monitoring device according to claim 3, characterized in that: The biodegradable conductive substrate is prepared using magnesium, zinc, or iron foil; the biodegradable polymer film is a film made of polylactic acid-glycolic acid copolymer; the conductive material is made by mixing tungsten powder and candelilla wax; the temperature-sensitive material is polyethylene glycol; and the biodegradable polymer film used in encapsulation is made of polylactic acid-glycolic acid copolymer.

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