Temperature self-correcting implantable blood glucose sensor

Abstract

The utility model discloses a temperature self-correcting implantable blood glucose sensor. The sensor mainly comprises a bin body, a power supply, a main board, a blood glucose processing module, a temperature correcting module, a Bluetooth receiving and transmitting module and a sensor probe module. The sensor probe module comprises a temperature detection electrode and a blood glucose detection electrode. Wherein the temperature detection electrode is an integrated electrode based on a thermistor, is attached to the surface of the blood glucose detection electrode and is used for detecting and sensing the real-time temperature of an implantation part, and the temperature change is fed back to the blood glucose detection module for correction, so that the measurement accuracy is improved. The device has the advantages of simple structure, high measurement accuracy, no environmental influence and the like, and is suitable for improving the long-term working stability of implantable blood glucose measurement equipment and the like.

Description

Technical Field

[0001] The utility model relates to the technical field of sensors, and particularly relates to an implantable blood glucose sensor with temperature self - calibration. Background Art

[0002] Traditional blood glucose monitoring usually requires measuring by collecting blood samples of patients. This method has problems such as the need for frequent blood sample collection, invasiveness, and inconvenience for long - term monitoring. To solve these problems, implantable blood glucose sensors have emerged. By puncturing the sensor electrode into the subcutaneous tissue of the patient, the function of continuously monitoring blood glucose concentration changes can be realized.

[0003] However, existing implantable blood glucose sensors still have some limitations and deficiencies in actual use. In particular, the accuracy of implantable blood glucose sensors is easily affected by various external factors, including human body and environmental temperature changes. The measurement of blood glucose concentration by the sensor comes from the current value of the electrochemical reaction, and the rate of the electrochemical reaction varies greatly under different temperature conditions. An increase in temperature will cause an increase in the current of the electrochemical reaction. The electrode of the implantable blood glucose is close to the epidermis and is easily affected by the outside world to produce temperature changes, which may cause the blood glucose reading to drift with temperature, thus affecting the effectiveness of diabetes management.

[0004] CN103549963A discloses an implantable real - time dynamic blood glucose monitoring device. The implantable real - time dynamic blood glucose monitoring device includes: a glucose sensor for real - time monitoring of blood glucose changes in the human body, generating a blood glucose available signal according to the blood glucose changes in the human body, and outputting the blood glucose available signal; a dynamic blood glucose monitoring device connected to the glucose sensor for processing the blood glucose available signal output by the glucose sensor; and a skin heating device for heating the skin tissue where the glucose sensor is implanted. Among them, the skin heating device includes: a skin heating film, a temperature - rising module, a temperature control module, a heat preservation module, and a temperature detection module. The implantable real - time dynamic blood glucose monitoring device can control the temperature of the human skin and reduce the influence of skin temperature changes on blood glucose monitoring.

[0005] The setting of this heat preservation device can reduce the influence of temperature changes on blood glucose monitoring, but the measurement accuracy still needs to be improved. Summary of the Utility Model

[0006] The utility model aims to solve the problem of temperature drift existing in existing implantable blood glucose sensors, reduce the numerical error caused by different environmental temperatures of existing sensors. The utility model patent can perform real - time calibration of blood glucose values according to the temperature detection electrode, making the measurement results more accurate and reliable.

[0007] To achieve the above - mentioned purpose, the technical solution adopted by the utility model is:

[0008] An implantable blood glucose sensor with self-temperature correction, comprising a housing and a cover plate. A main board is fixed inside the housing, and on the main board are a power module, a blood glucose data processing module, a temperature correction module, a Bluetooth transmission module, and a sensor probe module that are electrically connected; the main board is fixed to the housing by a buckle,

[0009] The sensor probe module includes a blood glucose detection electrode, a temperature detection electrode, an electrode fixing ring, and a flexible conductive rubber electrode contact;

[0010] The temperature detection electrode covers the periphery of the blood glucose detection electrode. The bottoms of both are connected and fixed to the electrode fixing ring, and the upper ends protrude through the through hole in the middle of the cover plate for fitting against the skin to detect the blood glucose value and temperature in the blood environment.

[0011] The electrode fixing ring is fixed to the main board, and a flexible conductive rubber electrode contact for connecting the blood glucose detection electrode and the temperature detection electrode is provided on the outer ring of the electrode fixing ring; the flexible conductive rubber electrode contact is also electrically connected to the main board circuit to transmit the detection data to the blood glucose data processing module and the temperature correction module;

[0012] The power module is used to supply power to all modules;

[0013] The blood glucose data processing module is used to connect to the blood glucose detection electrode; the temperature correction module is connected to the temperature detection electrode to correct the blood glucose value according to the temperature measured by the sensor; the Bluetooth transmission module is used to transmit all data to an external display device.

[0014] The sensor probe module in the present utility model has one more temperature detection electrode compared with a common sensor probe. To achieve temperature correction, an insulating layer is coated on the outside of the common sensor probe, and a temperature detection electrode is added on the insulating layer. The temperature detection electrode transmits the detected temperature value back to the temperature correction module, and through an algorithm, it feeds back to the blood glucose data processing module for correction according to the change in temperature, reducing the drift of the blood glucose value caused by temperature.

[0015] In the present utility model, there is a correction module for the change of blood glucose with temperature, and the real-time detection temperature of blood glucose is detected by the sensor probe module, and it feeds back to the blood glucose data processing module for correction according to the change in temperature to eliminate the temperature error in the measurement process and effectively avoid the influence of temperature change on the blood glucose value. This blood glucose sensor has the advantages of simple structure, high measurement accuracy, and being unaffected by the environment, and is suitable for improving the continuous measurement accuracy of implantable blood glucose measurement and other devices.

[0016] Preferably, the housing and the cover plate are fixedly connected and sealed with glue to prevent sweat, dust, or water vapor in the air from entering the housing and affecting the detection sensitivity and service life.

[0017] Preferably, an insulating layer is provided between the blood glucose detection electrode and the temperature detection electrode. The insulating layer is a polyurethane insulating layer to avoid mutual influence between the electrodes.

[0018] Preferably, the blood glucose detection electrode is longer than the temperature detection electrode. The blood glucose detection electrode detects the glucose concentration in the interstitial fluid of the subcutaneous tissue through the biological enzyme adsorbed on the electrode surface, so the surface of the blood glucose detection electrode cannot be sealed. The blood glucose detection electrode needs to have sufficient length to contact the interstitial fluid, while the temperature detection electrode has no such requirement and only needs to leave a reaction space for the blood glucose detection electrode.

[0019] Preferably, the positive pole of the power supply module contacts the battery slot, and the negative pole contacts the main board.

[0020] Preferably, the blood glucose detection electrode is a hollow cylinder with a tip. The blood glucose detection electrode is composed of a working electrode and a counter electrode. The working electrode and the counter electrode are attached to the opposite sides of the flexible cylindrical PET material by screen printing to transmit the detected blood glucose value back to the blood glucose data processing module.

[0021] Preferably, the blood glucose detection electrode and the temperature detection electrode are electrically connected to the electrode fixing ring. The flexible conductive rubber electrode contacts are also electrically connected to the blood glucose detection electrode and the temperature detection electrode.

[0022] Preferably, the electrode fixing ring penetrates the main board and is connected to the housing through a slot and a buckle. And the flexible conductive rubber electrode contacts are closely attached to the corresponding circuit of the main board under the pressure of the buckle to transmit the blood glucose data and the temperature data to the blood glucose data processing module and the temperature correction module.

[0023] Preferably, the sensor probe module is hermetically combined with the through hole of the cover plate.

[0024] Preferably, the temperature detection electrode is composed of a thermistor and a thyristor, and is attached to the surface of the blood glucose detection electrode to detect the real-time temperature of the sensing implantation site, transmit the temperature data back to the temperature correction module, and feedback to the blood glucose data processing module through an algorithm according to the change of the temperature for correction to improve the measurement accuracy.

[0025] Preferably, the lower surface of the cover plate has a sweat drainage groove, and the edge of the sweat drainage groove extends to the edge of the cover plate. The water vapor in the housing can be discharged to avoid the decrease of the detection sensitivity of the sensor in a long-term humid environment.

[0026] Preferably, an algorithm for calibrating the blood glucose level through temperature compensation is provided in the blood glucose data processing module and the temperature correction module.

[0027] Preferably, the algorithm includes receiving signals from a blood glucose detection electrode and receiving signals from a temperature detection electrode. Based on the measured temperature, the algorithm determines a corrected final blood glucose correction signal using a preset temperature correction coefficient.

[0028] Preferably, the main board further includes a potentiostat circuit, a chip resistor, a metal contact, a microprocessor chip, and other necessary parts and modules for connecting circuits and processing programs.

[0029] Compared with the prior art, the present utility model has the following beneficial effects:

[0030] The present utility model corrects the user's blood glucose value through the real-time temperature measurement data of the temperature detection electrode, effectively solving the influence of the temperature change at the implantation site of the implantable blood glucose sensor on the measurement accuracy of the sensor, and improving the reliability and stability of the implantable blood glucose sensor in application. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0032] Figure 1 It is a schematic structural diagram of an implantable blood glucose sensor detection device in the embodiment.

[0033] Figure 2 It is a schematic structural diagram of the sensor probe module in the embodiment.

[0034] Figure 3 It is a schematic anatomical diagram of the sensor probe module in the embodiment.

[0035] Figure 4 It is a current curve graph for testing the glucose concentration of the sensor probe in the embodiment.

[0036] Figure 5 It is a specific glucose concentration dot line graph for testing the glucose concentration of the sensor probe in the embodiment.

[0037] The reference numerals in the drawings are: housing 1, housing cover 2, power module 3, main board 4, blood glucose data processing module 5, temperature correction module 6, Bluetooth receiving and transmitting module 7, sensor probe module 8, blood glucose detection electrode 81, temperature detection electrode 82, insulating layer 83, electrode fixing ring 84, flexible conductive rubber electrode contact 85. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0038] In order to make the purpose, technical solutions and advantages of the present utility model more clear and understandable, the present utility model will be further described in detail below in conjunction with embodiments. It should be understood that the specific embodiments described herein are only used to explain the present utility model and are not used to limit the present utility model. Those skilled in the art who make modifications or equivalent replacements on the basis of understanding the technical solutions of the present utility model without departing from the spirit and scope of the technical solutions of the present utility model shall all be covered within the protection scope of the present utility model.

[0039] Embodiment 1

[0040] The present utility model discloses an implantable blood glucose sensor with a temperature self - calibration module, as Figures 1-3 shown, a main board 4 is fixed in a bin body 1, and on the main board 4 there are a power supply module 3, a blood glucose data processing module 5, a temperature calibration module 6, a Bluetooth transmission module 7 and a sensor probe module 8 which are electrically connected;

[0041] The bin body 1 is the installation skeleton of the whole sensor. The main board 4 is fixed to the bin body 1 by a buckle, and both the main board 4 and the bin body 1 have through - holes at the central position, which is convenient for installing the sensor probe module 8. The bin body cover plate 2 can be hermetically fixed to the bottom of the bin body 1 by glue, and the central position of the bin body cover plate 2 has through - holes corresponding to those of the bin body 1 and the main board 4, which is convenient for the blood glucose detection electrode 81 and the temperature detection electrode 82 of the sensor probe module 8 to expose the cover plate 2 and be implanted into the subcutaneous tissue layer of the human body. The power supply module 3 supplies power to the whole sensor system.

[0042] In the present utility model, the sensor probe module 8 includes a blood glucose detection electrode 81, a temperature detection electrode 82, an electrode fixing ring 84 and a flexible conductive rubber electrode contact 85; the blood glucose detection electrode 81 is composed of a working electrode and a counter electrode, which is responsible for monitoring the blood glucose of the user, and the temperature detection electrode 82 is an integrated electrode based on a thermistor, which is responsible for detecting the temperature change at the implantation site.

[0043] The temperature detection electrode 82 surrounds the blood glucose detection electrode 81, and is insulated by a polyurethane insulating layer 83 in the middle. Therefore, the distance between the tip of the blood glucose detection electrode 81 and the bottom surface of the bin body cover plate 2 needs to be greater than the distance between the outer end of the temperature detection electrode 82 and the bottom surface of the bin body cover plate 2, so that the tip of the temperature detection electrode 81 is more prominent than the outer end of the temperature detection electrode 82. The temperature measured by the temperature detection electrode 82 is transmitted back to the temperature calibration module 6, and the blood glucose value is micro - calibrated through a combined algorithm with the blood glucose data processing module 5, and is wirelessly transmitted to the corresponding upper computer by the Bluetooth receiving and transmitting module 7, solving the influence of the temperature change at the implantation site of the implantable blood glucose sensor on the measurement accuracy of the sensor.

[0044] During the actual operation process, the blood glucose data processing module 5 and the temperature correction module 6 form a blood glucose correction module. When the temperature correction module obtains the actual temperature, it matches with the set temperature correction coefficient, compensates the blood glucose value signal through an algorithm, and corrects the blood glucose value.

[0045] Using the configured standard glucose solution as the detection sample, heat 40 mL of PBS buffer solution in a water bath and maintain it at 40 °C. Place the sensor probe prepared by the present invention in the PBS buffer solution to level it, add 4 mL of 400 mM glucose solution, and the final glucose concentration is 4 mM. After 300 s, add another 4 mL of 400 mM glucose solution, and the final glucose concentration in the system is 8 mM. The detection results are as Figure 4 shown. The red curve is the curve actually measured by the blood glucose detection electrode, and the blue curve is the curve after the values are corrected with temperature compensation. According to the conversion, the final glucose concentrations of the two sample additions of the blue curve are 3.9 and 7.8 mM respectively.

[0046] Using the configured standard glucose solution as the detection sample, heat 40 mL of PBS buffer solution in a water bath and maintain it at 40 °C. Place the sensor probe prepared by the present invention in the PBS buffer solution to level it, and add glucose solutions with certain concentrations respectively, so that the final glucose concentration in the system increases successively (2, 4, 6, 8, 10, 14, 18, 22 mM). Record the sensor readings after temperature correction and the sensor readings without temperature correction respectively, and plot Figure 5 . The red dots are the values actually measured by the blood glucose sensor, and the blue dots are the values after correction with temperature compensation. It can be seen that the blue dots roughly coincide with the actual glucose concentration.

[0047] Even without these technical details and various changes and modifications based on the above embodiments, the technical solutions required to be protected by the present disclosure can also be realized. The division of the above embodiments is for convenience of description and should not constitute any limitation on the specific implementation manner of the present disclosure.

Claims

1. An implantable blood glucose sensor with temperature self - calibration, characterized in that, It includes a bin body (1) and a cover plate (2). A main board (4) is fixed inside the bin body (1). On the main board (4), there are a power supply module (3), a blood glucose data processing module (5), a temperature correction module (6), a Bluetooth transmission module (7) and a sensor probe module (8) which are electrically connected; The sensor probe module (8) includes a blood glucose detection electrode (81), a temperature detection electrode (82), an electrode fixing ring (84) and a flexible conductive rubber electrode contact (85); The temperature detection electrode (82) covers the periphery of the blood glucose detection electrode (81). The bottoms of both are connected and fixed to the electrode fixing ring (84), and the upper ends protrude through the through hole in the middle of the cover plate (2) for fitting the skin to detect the blood glucose value and temperature in the blood environment; The electrode fixing ring (84) is fixed on the main board (4). The outer ring of the electrode fixing ring (84) is provided with a flexible conductive rubber electrode contact (85) for connecting the blood glucose detection electrode (81) and the temperature detection electrode (82); The flexible conductive rubber electrode contact (85) is also electrically connected to the main board (4) to transmit the detection data to the blood glucose data processing module (5) and the temperature correction module (6); The power supply module (3) is used for supplying power to all modules; The blood glucose data processing module (5) is connected to the blood glucose detection electrode (81); The temperature correction module (6) is connected to the temperature detection electrode (82) to correct the blood glucose value according to the temperature measured by the sensor; The Bluetooth transmission module (7) is used to transmit all data to an external display device.

2. The temperature self-calibrating implantable blood glucose sensor according to claim 1, wherein The bin body (1) and the cover plate (2) are fixedly connected and sealed with glue.

3. The temperature self-calibrating implantable blood glucose sensor according to claim 1, characterized in that, An insulating layer (83) is provided between the blood glucose detection electrode (81) and the temperature detection electrode (82), and the insulating layer is a polyurethane insulating layer.

4. The temperature self-calibrating implantable blood glucose sensor according to claim 1, characterized in that, The blood glucose detection electrode (81) is longer than the temperature detection electrode (82); The positive pole of the power supply module (3) contacts the battery slot, and the negative pole contacts the main board (4).

5. The temperature self-calibrating implantable blood glucose sensor according to claim 1, wherein The blood glucose detection electrode (81) is a hollow cylinder with a tip. The blood glucose detection electrode (81) is composed of a working electrode and a counter electrode. The working electrode and the counter electrode are attached to the opposite sides of the flexible cylindrical PET material by screen printing to transmit the detected blood glucose value back to the blood glucose data processing module (5).

6. The temperature self-calibrating implantable blood glucose sensor according to claim 1, characterized in that, The blood glucose detection electrode (81) and the temperature detection electrode (82) are electrically connected to the electrode fixing ring (84).

7. The temperature self-calibrating implantable blood glucose sensor according to claim 1, wherein The sensor probe module (8) is hermetically combined with the through hole of the cover plate (2).

8. The temperature self-calibrating implantable blood glucose sensor according to claim 1, wherein, The temperature detection electrode (82) is composed of a thermistor.

9. The temperature self-calibrating implantable blood glucose sensor according to claim 1, wherein The lower surface of the cover plate (2) has a sweat drainage groove, and the edge of the sweat drainage groove extends to the edge of the cover plate (2).

10. The temperature self-calibrating implantable blood glucose sensor according to claim 1, wherein A chip for calibrating the blood glucose level through temperature compensation is provided in the blood glucose data processing module (5) and the temperature correction module (6).

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