Elastic Adaptive Microelectrode Element and Physiological Electrical Signal Measuring Device

Abstract

The present invention provides an elastic adaptive microelectrode element and a physiological electrical signal measuring device, comprising: a microelectrode element and an electrode fixing device; the microelectrode element is fixedly mounted on the electrode fixing device; a plurality of microelectrode contacts are arranged in an array on the side of the microelectrode element, and a microfluidic cavity is arranged inside the microelectrode element; a base electrode interface and a fixing device microfluidic channel are arranged on the electrode fixing device, the base electrode interface is electrically connected to the microelectrode contacts, and the fixing device microfluidic channel is connected to the microfluidic cavity. The present invention prepares a microelectrode array with a movable structure on an elastic substrate, realizes the overall elasticity of the electrode array, increases the contact area with the skin, reduces the contact impedance between the electrode and the skin, and improves the electrode sampling / stimulation signal capability.

Description

Technical Field

[0001] The invention relates to a physiological electrical signal measuring device, in particular to an elastic adaptive microelectrode element and a physiological electrical signal measuring device. Background Art

[0002] Currently, electrodes used for collecting physiological signals from the human body can be divided into implantable and non-invasive electrodes. Implantable electrodes require surgery, which makes them inconvenient to use and not well accepted. Non-invasive electrodes can be divided into wet electrodes, semi-dry electrodes, and dry electrodes. Wet electrodes and semi-dry electrodes require the addition of conductive gels and other additives to promote conductivity. They have the advantages of good stability and insensitivity to motion artifacts. However, the conductive gel will dry out, resulting in unstable performance, and are not suitable for daily long-term monitoring.

[0003] The most prominent advantage of dry electrodes is that they do not require electrolytes, but this results in a much higher contact impedance than wet electrodes. In addition, dry electrodes are easy to use, require a short preparation time, and are suitable for long-term monitoring, making them the first choice and research hotspot for various physiological monitoring devices in the future. However, dry electrodes still have the following key scientific and technological issues that need to be solved:

[0004] 1. The problem of high contact impedance with the skin. When the dry electrode contacts the skin, there will be air between them, resulting in high contact impedance. Increasing the contact ratio and contact area between the electrode and the skin is the main solution to reduce impedance.

[0005] 2. Electrode noise problem. The main sources of electrode noise are motion artifacts, flicker, thermal artifacts and line noise, which can be solved by improving wearing reliability and increasing back-end circuit compensation and filtering.

[0006] 3. Poor wearing comfort. Traditional electrodes are hard and have poor air permeability, which can cause sweating, skin compression and poor stability when worn for a long time. To solve this problem, research and optimization of materials and structures are needed to prepare flexible electrodes that can form a perfect fit with the skin.

[0007] The current existing technology references are as follows:

[0008] Patent document CN113545784A discloses a dry electrode and a resistance measuring device. The dry electrode includes an electrode base and a plurality of probes disposed on one side of the electrode base; the probes include a flexible substrate and a conductive medium disposed on the surface of the flexible substrate.

[0009] Patent document CN107411735A relates to a bioelectric signal flexible dry electrode and its preparation method. The electrode is suitable for conducting EEG (forehead area), muscle electrical signals, ECG and other signals in hairless or hairless areas. The dry electrode consists of two parts: a conductive flexible dry electrode body and an electrical connector. The conductive flexible dry electrode body is made of a flexible composite conductive material; the surface is a three-dimensional curved surface. Summary of the invention

[0010] In view of the defects in the prior art, the object of the present invention is to provide an elastic adaptive microelectrode element and a physiological electrical signal measuring device.

[0011] An elastic adaptive micro-electrode element provided according to the present invention comprises: a micro-electrode element and an electrode fixing device;

[0012] The microelectrode element is fixedly mounted on the electrode fixing device;

[0013] A plurality of microelectrode contacts are arranged in an array on the side of the microelectrode element, and a microfluidic cavity is arranged inside the microelectrode element;

[0014] The electrode fixing device is provided with a base electrode interface and a fixing device micro-channel, the base electrode interface is electrically connected to the micro-electrode contact, and the fixing device micro-channel is connected to the micro-channel cavity.

[0015] Preferably, the microchannel of the fixing device is connected to an electronic air pump, the base electrode interface is connected to a signal measuring device, and the electronic air pump and the signal measuring device are connected to a controller.

[0016] Preferably, the microelectrode element further comprises: a microelectrode element connector, an elastic substrate and a microchannel connector;

[0017] A plurality of microelectrode contacts are arranged in an array on one side of the elastic substrate, and the microchannel cavity is arranged inside the elastic substrate;

[0018] The microelectrode component connector and the microfluidic channel connector are arranged on the side of the elastic substrate facing away from the microelectrode contacts. The microelectrode component connector is electrically connected to the microelectrode contacts, and the microfluidic channel connector is connected to the microfluidic channel cavity.

[0019] Preferably, the connection method of the microelectrode contact to the microelectrode element connector includes:

[0020] A plurality of the microelectrode contacts are connected to each other and then directly connected to the microelectrode element connector;

[0021] Alternatively, a plurality of microelectrode connecting wires are arranged on the elastic substrate, the microelectrode connecting wires are connected to the microelectrode element connector, and the microelectrode contacts are respectively connected to different microelectrode connecting wires via one or more microelectrode contact connectors.

[0022] Preferably, the electrode fixing device comprises: an upper half of the fixing device and a lower half of the fixing device;

[0023] The lower half of the fixing device is connected to the upper half of the fixing device;

[0024] The fixture microchannel and fixture connecting wire are arranged between the lower half of the fixture and the upper half of the fixture.

[0025] Preferably, one or more fixing device bases are provided on the upper part of the fixing device;

[0026] The base electrode interface, the base microchannel interface and the fixed joint are arranged on the base of the fixing device;

[0027] The microelectrode element is fixedly mounted on the base of the fixing device through the fixing joint, the microelectrode element connector is connected to the base electrode interface, and the microchannel connector is connected to the base microchannel interface.

[0028] Preferably, the base microfluidic interface is connected to the electronic air pump through the fixture microfluidic channel;

[0029] The base electrode interface is connected to a signal measuring device through a wire connected to the fixing device.

[0030] Preferably, the elastic substrate, the microchannel connection port and the microchannel cavity are made of human body silicone.

[0031] Preferably, the upper half of the fixing device is bonded to the lower half of the fixing device;

[0032] The material of the lower half of the fixing device includes PI polymer material;

[0033] The fixing device micro-channel preparation material includes tetrafluoroethylene micro-tubes.

[0034] Preferably, the elastic base, the upper part of the fixing device and the lower part of the fixing device are elastic.

[0035] The present invention can greatly improve the deformation ability of the microelectrode array, and at the same time realize the dynamic adjustment and balance of the contact force between each microelectrode in the microelectrode array and the skin through the microchannel cavity and the electronic air pump, while ensuring the comfort of long-term wearing, thereby reducing the contact impedance and improving the stability, and reducing the measurement noise.

[0036] Compared with the prior art, the present invention has the following beneficial effects:

[0037] 1. The present invention prepares a microelectrode array with a movable structure on an elastic substrate, realizes the overall elasticity of the electrode array, increases the contact area with the skin, reduces the contact impedance between the electrode and the skin, and improves the electrode sampling / stimulation signal capability;

[0038] 2. The present invention sets a microchannel on the elastic substrate, and based on the initial impedance detection result, uses an air pump to dynamically adjust the fit between the microelectrode array and the skin, thereby reducing the contact impedance without affecting the wearing comfort;

[0039] 3. The present invention ensures comfort during long-term wearing through elastic microelectrode elements, elastic fixing devices and adaptive dynamic adjustment;

[0040] 4. The microelectrode contact array has a high specific surface area, which improves the sensitivity of electrode sampling, minimizes contact impedance, improves stability and reduces noise. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0042] Figure 1 It is a schematic diagram of the overall structure of the microelectrode element installed on the electrode fixing device;

[0043] Figure 2 Schematic diagram of the microelectrode element structure (I);

[0044] Figure 3 Schematic diagram of the microelectrode element structure (II);

[0045] Figure 4 It is a half-section view of a microelectrode element;

[0046] Figure 5 Schematic diagram of the microelectrode contact structure;

[0047] Figure 6 is a half-section view of the electrode fixing device;

[0048] As shown in the figure:

[0049] DETAILED DESCRIPTION

[0050] The present invention is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several changes and improvements can also be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0051] Example 1

[0052] like Figure 1 As shown, this embodiment provides an elastic adaptive microelectrode element that can be used for physiological electrical signal measurement, including: a microelectrode element 1 and an electrode fixture 2; the microelectrode element 1 is fixedly mounted on the electrode fixture 2, a plurality of microelectrode contacts 14 are arranged in an array on the side of the microelectrode element 1, a microfluidic cavity 17 is arranged inside the microelectrode element 1, and a fixture microfluidic channel 23 is arranged on the electrode fixture 2, and the fixture microfluidic channel 23 is connected to the microfluidic cavity 17. The fixture microfluidic channel 23 is connected to an electronic air pump, the microelectrode contact 14 is connected to a signal measuring device, and the electronic air pump and the signal measuring device are connected to a controller. The controller controls the electronic air pump to adjust the microfluidic cavity 17 according to the information fed back by the microelectrode contact 14 through the signal measuring device, thereby realizing the adjustment of the microelectrode element 1 array, realizing the dynamic adjustment and balancing of the contact force between each microelectrode element 1 in the microelectrode element 1 array and the skin, and at the same time, the microelectrode contact 14 has a high specific surface area and high sampling sensitivity, which can minimize the contact impedance, improve stability and reduce noise.

[0053] like Figures 2 to 5 As shown, the microelectrode element 1 further includes: a microelectrode element connector 12, an elastic substrate 13 and a microfluidic connection port 15; a plurality of microelectrode contacts 14 are arranged in an array on one side of the elastic substrate 13, a microfluidic cavity 17 is arranged inside the elastic substrate 13, a microelectrode element connector 12 and a microfluidic connection port 15 are arranged on the side of the elastic substrate 13 facing away from the microelectrode contacts 14, the microelectrode element connector 12 is electrically connected to the microelectrode contacts 14, and the microfluidic connection port 15 is connected to the microfluidic cavity 17. The connection method of the microelectrode contact 14 to the microelectrode element connector 12 includes: a plurality of microelectrode contacts 14 are connected to the microelectrode element connector 12 directly after being connected to each other; or, a plurality of microelectrode connection wires 11 are arranged on the elastic substrate 13, the microelectrode connection wires 11 are connected to the microelectrode element connector 12, and the microelectrode contact 14 is respectively connected to different microelectrode connection wires 11 through one or more microelectrode contact joints 16. The elastic substrate 13, the microfluidic connection port 15 and the microfluidic cavity 17 are made of human silicone.

[0054] like Figure 6As shown, the electrode fixture 2 comprises: a fixture upper part 22 and a fixture lower part 25; the fixture lower part 25 is connected to the fixture upper part 22, and a fixture microchannel 23 and a fixture connecting wire 24 are arranged between the fixture lower part 25 and the fixture upper part 22. The fixture upper part 22 is provided with one or more circular groove-shaped fixture bases 27, each fixture base 27 is installed with a microelectrode element 1, and the fixture base 27 is provided with a base electrode interface 21, a base microchannel interface 26 and a fixing joint 28, the microelectrode element 1 is fixedly installed on the fixture base 27 through the fixing joint 28, the microelectrode element connector 12 is connected to the base electrode interface 21, and the microchannel connection port 15 is connected to the base microchannel interface 26. The base microchannel interface 26 is connected to the electronic air pump through the fixture microchannel 23, and the base electrode interface 21 is connected to the signal measuring device through the fixture connecting wire 24. The upper part 22 of the fixture is bonded to the lower part 25 of the fixture. The material of the lower part 25 of the fixture includes PI polymer material. The material of the fixture microchannel 23 includes tetrafluoroethylene microtubes.

[0055] Example 2

[0056] Example 2 is a preferred example of Example 1.

[0057] like Figures 1 to 6 As shown, this embodiment provides an elastic adaptive microelectrode element and a physiological electrical signal measuring device, which can be used for impedance imaging, heart rate belts, chest electrical signals, brain electrical signals and other physiological electrical signal measurements. When in use, the device is worn on the measuring part, such as the head or chest, with one side of the electrode close to the skin.

[0058] This embodiment can greatly improve the deformation ability of the microelectrode contact 14 array, and use microfluidic technology to dynamically adjust and balance the contact force between each microelectrode element 1 in the microelectrode array and the skin, ensuring that the high-performance elastic electrode can perfectly fit the skin and keep perfect fit with the skin at any time as the human body moves, while ensuring comfort for long-term wearing. It achieves ultra-low contact impedance and ultra-high stability, reduces measurement noise, and can integrate the microelectrode element 1 with the active chip to further improve the performance of the microelectrode element 1.

[0059] This embodiment includes: a microelectrode element 1 and an electrode fixing device 2, the electrode fixing device 2 includes but is not limited to a strip-shaped, sheet-shaped, cap-shaped, etc., one or more fixing device bases 27 are arranged on the electrode fixing device 2, and one or more elastic microelectrode elements 1 are installed on the electrode fixing device 2 through the fixing device base 27.

[0060] The microelectrode element 1 comprises: an elastic substrate 13 and an array of microelectrode contacts 14 on the elastic substrate 13, and the connection of the microelectrode contacts 14 includes but is not limited to the following methods: each microelectrode contact 14 has one or more microelectrode contact connectors 16 at the bottom thereof, which are respectively connected to different microelectrode connection wires 11, and each different microelectrode connection wire 11 is connected to the corresponding contact of the microelectrode element connector 12. In some other embodiments, the array of microelectrode contacts 14 is connected to each other and directly connected to the microelectrode element connector 12. The elastic substrate 13 contains a hollow microfluidic cavity 17, and the microfluidic cavity 17 is connected to the microfluidic connection port 15.

[0061] The base electrode interface 21, the base microfluidic interface 26 and the fixing joint 28 are arranged on the fixing device base 27; the fixing joint 28 includes but is not limited to a physical fixing buckle or a magnetic buckle. The microelectrode element connector 12 is connected to the fixing device connecting wire 24 corresponding to the base electrode interface 21. In some other embodiments, the microelectrode element 1 can use a wireless connection to achieve communication or power supply. The microfluidic cavity 17 of each microelectrode element 1 is connected to the base microfluidic interface 26 through the microfluidic connection port 15.

[0062] The electrode fixture 2 includes: a fixture upper part 22, a fixture lower part 25, a fixture microchannel 23 between the fixture upper part 22 and the fixture lower part 25, a fixture connecting wire 24, and one or more fixture bases 27 on the fixture upper part 22. The fixture microchannel 23 is connected to a base microchannel interface 26 of the fixture base 27. Each fixture connecting wire 24 is connected to a contact corresponding to the base electrode interface 21.

[0063] Connect the fixture connecting wire 24 to the signal measuring device, connect the fixture microchannel 23 to the electronic air pump, and connect the electronic air pump, the signal measuring device and the controller. After wearing, the controller will automatically adjust the electronic air pump according to the measured impedance data, adjust the air pressure of the microchannel cavity 17 in the microelectrode element 1 to achieve the best fit with the skin, so that the measured impedance is minimized and automatically and continuously maintained stable, while ensuring the comfort of long-term wearing.

[0064] The preparation process of this embodiment is as follows:

[0065] (1) Preparation of microelectrode element 1: The elastic substrate 13, microfluidic cavity 17, and microfluidic connection port 15 are made of elastic polymer materials including but not limited to human silicone and are prepared by mold casting; the microelectrode connecting wire 11 and microelectrode contact 14 are made of conductive materials including but not limited to metal copper and are prepared by micro-electroforming process; the microelectrode element connector 12 includes a plurality of different contacts, which are respectively connected to the corresponding microelectrode connecting wire 11. Metal copper or other conductive materials are used, and processes including but not limited to micro-electroforming are used to prepare.

[0066] (2) Prepare the electrode fixture 2, taking the strip shape as an example: the lower part 25 of the fixture is made of polymer materials including but not limited to PI, and is prepared by methods including but not limited to mold casting; the fixture connecting wire 24 is prepared on the lower part 25 of the fixture using methods including but not limited to FPCB process; the lower part 25 of the fixture uses materials including but not limited to tetrafluoroethylene microtubes as the fixture microchannel 23; the upper part 22 of the fixture is made of polymer materials including but not limited to PI, and is prepared by methods including but not limited to mold casting; the fixture base 27 is prepared using but not limited to polymer materials , prepare the fixture base 27 by means including but not limited to mold casting; fix the fixture base 27 to the fixture upper part 22, or use methods including but not limited to mold casting to integrally prepare the fixture base 27 and the fixture upper part 22; bond the fixture upper part 22 to the fixture lower part 25, using methods including but not limited to hot bonds and process bonding, so that the fixture connecting wire 24 is connected to the corresponding contact on the base electrode interface 21 of the corresponding fixture base 27, and the fixture microchannel 23 is connected to the corresponding base microchannel interface 26 of the fixture base 27.

[0067] (3) Assembling the electrode fixture 2 and the microelectrode element 1: buckle the prepared one or more microelectrode elements 1 into the corresponding one or more fixture bases 27 on the electrode fixture 2, so that the microfluidic connection port 15 of the microelectrode element 1 is connected to the base microfluidic interface 26 of the fixture base 27. Connect the microelectrode element 1 to the corresponding fixing joint 28 on the electrode fixture 2 and fix them firmly. One or more microelectrode elements 1 can be selected for assembly and measurement according to the specific measurement application.

[0068] In the description of the present application, it should be understood that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0069] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. In the absence of conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims

1. An elastic adaptive microelectrode element, It is characterized in that include: Microelectrode element (1) and electrode fixing device (2); The microelectrode element (1) is fixedly mounted on the electrode fixing device (2); A plurality of microelectrode contacts (14) are arranged in an array on the side of the microelectrode element (1), and a microfluidic cavity (17) is arranged inside the microelectrode element (1); A fixture microchannel (23) is provided on the electrode fixture (2), and the fixture microchannel (23) is connected to the microchannel cavity (17); The fixing device microchannel (23) is connected to an electronic air pump.

2. The elastic adaptive microelectrode element according to claim 1, Features: The microelectrode contact (14) is connected to a signal measuring device, and the electronic air pump and the signal measuring device are connected to a controller.

3. The elastic adaptive microelectrode element according to claim 1, It is characterized in that The microelectrode element (1) further comprises: a microelectrode element connector (12), an elastic substrate (13) and a microchannel connector (15); A plurality of microelectrode contacts (14) are arranged in an array on one side of the elastic substrate (13), and the microchannel cavity (17) is arranged inside the elastic substrate (13); The microelectrode element connector (12) and the microfluidic channel connector (15) are arranged on the side of the elastic base (13) facing away from the microelectrode contact (14); the microelectrode element connector (12) is electrically connected to the microelectrode contact (14); and the microfluidic channel connector (15) is connected to the microfluidic channel cavity (17).

4. The elastic adaptive microelectrode element according to claim 3, It is characterized in that The connection method of the microelectrode contact (14) to the microelectrode element connector (12) includes: A plurality of microelectrode contacts (14) are connected to each other and then directly connected to the microelectrode element connector (12); Alternatively, a plurality of microelectrode connecting wires (11) are arranged on the elastic substrate (13), the microelectrode connecting wires (11) are connected to the microelectrode element connecting piece (12), and the microelectrode contacts (14) are respectively connected to different microelectrode connecting wires (11) via one or more microelectrode contact connectors (16).

5. The elastic adaptive microelectrode element according to claim 3, It is characterized in that The electrode fixing device (2) comprises: an upper fixing device part (22) and a lower fixing device part (25); The fixing device lower part (25) is connected to the fixing device upper part (22); The fixture microchannel (23) and the fixture connecting wire (24) are arranged between the fixture lower part (25) and the fixture upper part (22).

6. The elastic adaptive microelectrode element according to claim 5, Features: The upper part (22) of the fixing device is provided with one or more fixing device bases (27); The fixing device base (27) is provided with a base electrode interface (21), a base microfluidic channel interface (26) and a fixing joint (28); The microelectrode element (1) is fixedly mounted on the fixing device base (27) via the fixing joint (28), the microelectrode element connector (12) is connected to the base electrode interface (21), and the microfluidic channel connector (15) is connected to the base microfluidic channel interface (26).

7. The elastic adaptive microelectrode element according to claim 6, Features: The base microfluidic channel interface (26) is connected to the electronic air pump through the fixing device microfluidic channel (23); The base electrode interface (21) is connected to a signal measuring device via a connecting wire (24) of the fixing device.

8. The elastic adaptive microelectrode element according to claim 3, Features: The elastic base (13), the microchannel connection port (15) and the microchannel cavity (17) are made of human silicone.

9. The elastic adaptive microelectrode element according to claim 3, Features: The upper part (22) of the fixing device is bonded to the lower part (25) of the fixing device; The material of the lower part (25) of the fixing device includes PI polymer material; The fixing device microchannel (23) is prepared from materials including tetrafluoroethylene microtubes.

10. A physiological electrical signal measuring device, Features: The elastic adaptive microelectrode element according to any one of claims 1 to 9 is used.

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