Sensor

Abstract

Provided is a sensor capable of suppressing deviation in the state where the sensor is in contact with a living body.　A sensor 1 converts, to an electrical signal, the amount of a substance to be measured contained in a secretion from a living body H, the sensor 1 comprising: a sensor main body 10 having an electrode part 11 that is disposed on the contact surface side contacting the living body H and a substrate 12 that is disposed on the exposed surface side opposite to the contact surface; and a fixing part 20 for fixing the sensor main body 10 to the living body H, wherein the fixing part 20 has a flexible sheet 21 that is attached to the living body H and fixes the sensor main body 10 to the living body H, and a spacer part 22 that is disposed between the flexible sheet 21 and the exposed surface and has a thickness equal to or thicker than that of the sensor main body 10.

Description

Technical Field

[0001] The present invention relates to a sensor.

Background Art

[0002] Conventionally, sensors for measuring a substance to be measured contained in a secretion from a living body have been known. The sensor includes an absorption layer capable of absorbing the secretion, an enzyme layer containing an enzyme, and an electrode portion. The sensor detects, by the electrode portion, an electrode-detectable substance generated from the substance to be measured in the presence of the enzyme (see Non-Patent Documents 1 and 2).

Prior Art Documents

Non-Patent Documents

[0003]

Non-Patent Document 1

Non-Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, the sensor is positioned and brought into contact at a predetermined position of the living body. In continuous measurement, measurement may not be stably performed because the sensor moves from the contact position. Therefore, it is preferable that the sensor is suppressed from shifting while being in contact with the contact position during measurement.

[0005] The present invention has been made in view of the above problems, and an object thereof is to provide a sensor capable of suppressing displacement while being in contact with a living body.

Means for Solving the Problems

[0006] The present invention relates to a sensor that converts the amount of a substance to be measured contained in a secretion from a living body into an electrical signal, and includes a sensor body having an electrode portion disposed on the contact surface side in contact with the living body and a base material disposed on the exposed surface side opposite to the contact surface, and a fixing portion that fixes the sensor body to the living body. The fixing portion includes a flexible sheet that is attached to the living body and fixes the sensor body to the living body, and a spacer portion disposed between the flexible sheet and the exposed surface, the spacer portion being the same thickness as or thicker than the sensor body.

[0007] Further, the flexible sheet preferably has an adhesive layer on the surface in contact with the living body, and the spacer portion is preferably attached to the flexible sheet by the adhesive layer.

[0008] Further, the flexible sheet preferably has an area larger than the contact surface with the spacer portion.

[0009] Further, the sensor preferably further includes a covering portion that covers the fixing portion and presses the fixing portion against the living body.

[0010] Further, the sensor body preferably contacts the forehead, upper arm, back, or wrist of the human body.

[0011] Further, the electrode portion preferably includes an absorption layer capable of absorbing the secretion, an enzyme layer containing an enzyme that reacts with the absorbed secretion, and an electrode layer that converts the reaction with the secretion into an electrical signal.

[0012] Further, the enzyme layer preferably contains at least one selected from lactate oxidase, glucose oxidase, and alcohol oxidase.

[0013] Further, the absorption layer includes a polymer material having a chemically bonded crosslinked structure, and the absorption layer preferably covers the end faces of the enzyme layer and the electrode layer.

Advantages of the Invention

[0014] According to the present invention, it is possible to provide a sensor capable of suppressing displacement while being in contact with a living body.

Brief Description of the Drawings

[0015]

Figure 1

Figure 2

Figure 3

Mode for Carrying Out the Invention

[0016] Hereinafter, a sensor 1 according to an embodiment of the present invention will be described with reference to FIGS. 1 to 3. First, an overview of the sensor 1 will be described. The sensor 1 measures, for example, a substance to be measured contained in a secretion from a living body. The sensor 1 absorbs the secretion and generates an electrode-detectable substance from the substance to be measured contained in the absorbed secretion. The sensor 1 electrically detects the concentration of the electrode-detectable substance by measuring the current value generated by the electrochemical reaction of the generated electrode-detectable substance. Thereby, the sensor 1 electrically detects the concentration of the substance to be measured contained in the secretion from the living body H.

[0017] The sensor 1 is fixed with respect to the position of the living body H that measures the substance to be measured during measurement. By being fixed in a state of being in contact with the living body H, the sensor 1 can continuously measure the secretion over time. In the following embodiments, the sensor 1 is maintained in a state of being fixed to the position of the living body H that measures the substance to be measured, so as to appropriately absorb the secretion at a predetermined position of the living body H.

[0018] Note that the sensor 1 measures a substance to be measured contained in secretions from the living body H, such as sweat, tears, saliva, urine, etc. The sensor 1 measures, as the substance to be measured, for example, lactic acid, glucose, ethanol, uric acid, urea, vitamins, free cholesterol, phosphate ions, etc. Among these secretions, sweat is preferable from the viewpoints of the fixing method and the position of contact with the living body.

[0019] Next, the structure of the sensor 1 of the present embodiment will be described. The sensor 1 is a sensor 1 that converts the amount of a substance to be measured contained in secretions from the living body H into an electrical signal. The sensor 1 electrically converts, for example, the amount of a substance to be measured contained in secretions from a human or a horse as the living body H. The sensor 1 is fixed in contact with, for example, the forehead, upper arm, back, or wrist of the human body. As shown in FIGS. 1 and 2, the sensor 1 includes a sensor body 10, a fixing portion 20, and a covering portion 30.

[0020] As shown in FIG. 2, the sensor body 10 is a device that actually contacts the living body H and measures the amount of the substance to be measured. The sensor body 10 includes an electrode portion 11 and a base material 12. Although there is no particular specification for the size of the sensor body 10, from the viewpoints of the fixing method and the position of contact with the living body, it is preferable to use one having a width smaller than the diameter of the flexible sheet 21 in a plan view of the position overlapping the flexible sheet 21 described later.

[0021] The electrode portion 11 is disposed on the contact surface side that contacts the living body H. The electrode portion 11 absorbs the secretion of the living body H and measures the current value generated by the electrode-detectable substance. As shown in FIG. 3, the electrode portion 11 has an absorption layer 111, an enzyme layer 112, and an electrode layer 113.

[0022] The absorption layer 111 is a layer capable of absorbing secretions. The absorption layer 111 is disposed on the side of the surface of the base material 12 described later that faces the living body H. The absorption layer 111 contains a polymer material having a chemically bonded crosslinked structure. The absorption layer 111 covers the end faces of the enzyme layer 112 and the electrode layer 113 described later. The absorption layer 111 is composed of, for example, a polymer material having a chemically bonded crosslinked structure. The absorption layer 111 is configured to be able to absorb secretions by contacting the living body H.

[0023] The enzyme layer 112 is a layer containing an enzyme that reacts with the absorbed secretions. The enzyme layer 112 contains an enzyme. The enzyme layer 112 is covered by the absorption layer 111. The enzyme layer 112 can contain, for example, lactate oxidase (lactic acid oxidase), glucose oxidase (glucose oxidase), alkaline phosphatase, alcohol oxidase, uricase, L-amino acid oxidase, urease, cholesterol oxidase, phosphatase, horseradish peroxidase, etc. Among these, it is preferable to contain at least one selected from lactate oxidase, glucose oxidase, and alcohol oxidase from the viewpoints of the fixing method and the position of contact with the living body.

[0024] The electrode layer 113 is disposed between the base material 12 and the enzyme layer 112. Further, the electrode layer 113 converts the reaction with the secretions into an electrical signal.

[0025] The base material 12 is disposed on the exposed surface side opposite to the contact surface. The base material 12 supports the electrode portion 11. As the base material 12, for example, thermoplastic elastomers such as styrene-based thermoplastic elastomers, olefin-based thermoplastic elastomers, diene-based thermoplastic elastomers, vinyl chloride-based thermoplastic elastomers, urethane-based thermoplastic elastomers, and silicone-based thermoplastic elastomers, polyethylene, polypropylene, polystyrene, polyethylene terephthalate, cellulose, acrylonitrile / styrene (AS) resin, glass epoxy, acrylonitrile / butadiene / styrene (ABS) resin, methacrylic resin, thermoplastic resins such as vinyl chloride, polyamide resin, polyimide resin, etc. can be used. Among these, thermoplastic elastomers are preferred because of their excellent supportability and flexibility.

[0026] The fixing portion 20 is used to fix the sensor body 10 to the living body H. The fixing portion 20 is configured to have a size and shape that contacts the exposed surface of the base material 12 and can contact the surface of the living body H. The fixing portion 20 includes a flexible sheet 21 and a spacer portion 22.

[0027] The flexible sheet 21 is attached to the living body H and fixes the sensor body 10 to the living body H. The flexible sheet 21 has an adhesive layer on the surface that contacts the living body H.

[0028] The spacer portion 22 is disposed between the flexible sheet 21 and the exposed surface of the base material 12. The spacer portion 22 contacts the flexible sheet 21, for example, by a contact surface opposite to the surface facing the base material 12. Also, the spacer portion 22 is configured to be the same as or thicker than the sensor body 10. The spacer portion 22 is configured to have a width larger than, for example, the width of the base material 12. The spacer portion 22 is configured to be able to transmit the pressing force generated by attaching the flexible sheet 21 to the living body H to the base material 12. The spacer portion 22 is made of a material having a Young's modulus capable of maintaining the sensor body 10 in a continuously contacting state with the living body H against the strain generated by, for example, the pressing force when being pressed from the flexible sheet 21 to the base material 12, the shape of the sensor body 10, and the repulsive force from the living body H. Although there is no particular specification for the material, for example, non-woven fabric, cloth, cotton, compressed cotton, gauze, other absorbent materials, or combinations thereof can be used.

[0029] According to the above flexible sheet 21 and spacer portion 22, the flexible sheet 21 has an area larger than the contact surface of the spacer portion 22. Thereby, the flexible sheet 21 is configured to be able to directly contact the living body H. Also, the flexible sheet 21 has an adhesive layer on the surface contacting the living body H. Also, the flexible sheet 21 has an adhesive layer also at the portion contacting the spacer portion 22. The spacer portion 22 is attached to the flexible sheet 21 by the adhesive layer. The spacer portion 22 is provided together with the flexible sheet 21 in a state of being adhered to the flexible sheet 21, for example.

[0030] The covering portion 30 covers the sensor body 10 and the fixing portion 20, for example, between the covering portion 30 and the living body H. The covering portion 30 is, for example, a wearable item for the living body H such as a band containing an elastic body. By being worn on the living body H, the covering portion 30 presses the sensor body 10 and the fixing portion 20 toward the living body H. The covering portion 30 is configured to have a width capable of covering the spacer portion 22, for example. By having the covering portion 30, it is possible to suppress displacement in a state where the sensor body 10 is continuously in contact with the living body.

[0031] Next, the operation of sensor 1 will be described. First, the sensor body 10 is brought into contact with the measurement position of the living body H to be measured. At this time, the sensor body 10 is brought into contact with the living body H with the exposed surface of the base material 12 exposed. Also, the sensor body 10 is brought into contact with the position of the living body H that has been previously washed with water, a buffer solution such as physiological saline, alcohol, etc. Next, the fixing portion 20 is attached to the living body H. Specifically, the fixing portion 20 is attached to the living body H by bringing the adhesive layer into contact with the living body H in a state where the spacer portion 22 is in contact with the exposed surface of the base material 12. Next, the covering portion 30 is positioned at a position to cover the fixing portion 20 and is attached to the living body H. Thereby, the sensor 1 is attached to the living body H.

[0032] According to the sensor 1 according to the above-described embodiment, the following effects can be obtained.

[0033] (1) A sensor 1 that converts the amount of the substance to be measured contained in the secretion from the living body H into an electrical signal, comprising: a sensor body 10 having an electrode portion 11 disposed on the contact surface side in contact with the living body H and a base material 12 disposed on the exposed surface side opposite to the contact surface; and a fixing portion 20 for fixing the sensor body 10 to the living body H. The fixing portion 20 is attached to the living body H and includes a flexible sheet 21 for fixing the sensor body 10 to the living body H, and a spacer portion 22 disposed between the flexible sheet 21 and the exposed surface and having the same or a greater thickness as the sensor body 10. Thereby, the sensor body 10 can be appropriately pressed against the surface of the living body H, so that displacement can be suppressed in a state of being continuously in contact with the living body H.

[0034] (2) The flexible sheet 21 has an adhesive layer on the surface that contacts the living body H, and the spacer portion 22 is attached to the flexible sheet 21 by the adhesive layer. As a result, the sensor body 10 can be maintained in a state of contacting the living body H, so that measurement can be facilitated. For example, after determining the contact position of the sensor body 10 with respect to the living body H, the workability when fixing the sensor body 10 to the living body H can be improved. Also, after fixation, by reducing the displacement of the contact position of the sensor body 10 with respect to the living body H, a biological signal can be appropriately acquired.

[0035] (3) The flexible sheet 21 has an area larger than the contact surface with the spacer portion 22. Thereby, the state of pressing the spacer portion 22 can be easily maintained.

[0036] (4) The sensor 1 is a covering portion 30 that covers the fixing portion 20, and further includes a covering portion 30 that presses the fixing portion 20 against the living body H. Thereby, the displacement of the sensor body 10 with respect to the living body H can be more effectively suppressed.

[0037] (5) The sensor body 10 contacts the forehead, upper arm, back, or wrist of the human body. Thereby, the versatility of the sensor 1 can be improved.

[0038] (6) The electrode portion 11 has an absorption layer 111 that can absorb secretions, an enzyme layer 112 that contains an enzyme that reacts with the absorbed secretions, and an electrode layer 113 that converts the reaction with the secretions into an electrical signal. Thereby, the amount of the analyte contained in the secretions can be easily measured.

[0039] As described above, the preferred embodiments of the sensor of the present invention have been described. However, the present invention is not limited to the above-described embodiments and can be appropriately modified.

[0040] For example, in the above embodiment, the covering portion 30 is assumed to cover the entire fixing portion 20, but it is not limited thereto. The covering portion 30 only needs to be able to cover the portion of the spacer body.

[0041] In addition, in the above embodiment, the shape of the flexible sheet 21 may be changed according to the measurement position of the living body H. For example, when the sensor 1 is attached to the forehead, the flexible sheet 21 may have a planar shape with a longer long side according to the forehead. Further, when the sensor 1 is attached to the upper arm, the flexible sheet 21 may have a planar shape close to a square or a circle and may have a size that does not inhibit the movement of the portion where the sensor body is in contact. Further, the spacer portion 22 preferably has a planar shape close to a square or a circle, similar to the flexible sheet 21. Note that the spacer portion 22 only needs to be able to maintain the state in which the sensor body 10 is in contact with the living body H. The spacer portion 22 may be configured with an area smaller than that of the sensor body 10 in a plan view, for example.

Explanation of reference numerals

[0042] 1 Sensor H Living body 10 Sensor body 11 Electrode portion 12 Base material 20 Fixing portion 21 Flexible sheet 22 Spacer portion 30 Coating portion 111 Absorption layer 112 Enzyme layer 113 Electrode layer

Claims

1. A sensor that converts the amount of a substance to be measured contained in a secretion from a living body into an electrical signal, comprising: an absorption layer capable of absorbing the secretion having a contact surface that contacts the living body; an enzyme layer containing an enzyme that reacts with the absorbed secretion; and an electrode portion having an electrode layer that converts the reaction with the secretion into an electrical signal; and a sensor body having a base material with an exposed surface opposite to the contact surface; a fixing portion that fixes the sensor body to the living body by contacting the exposed surface; and comprising: The fixing portion is a flexible sheet that is attached to the living body and fixes the sensor body to the living body; a spacer portion disposed between the flexible sheet and the exposed surface, configured to transmit the pressing force generated by the attachment of the flexible sheet to the living body to the sensor body, and having a Young's modulus capable of maintaining the sensor body in a continuously contacting state with the living body against the strain generated by the pressing force when pressed from the flexible sheet to the sensor body, the shape of the sensor body, and the repulsive force from the living body; A sensor having the above.

2. The flexible sheet has an adhesive layer on the surface that contacts the living body, The sensor according to claim 1, wherein the spacer portion is attached to the flexible sheet by the adhesive layer.

3. The sensor according to claim 1 or 2, wherein the flexible sheet has an area larger than the contact surface with the spacer portion.

4. A covering portion that covers the fixing portion, further comprising a covering portion that presses the fixing portion against the living body, the sensor according to any one of claims 1 to 3.

5. The sensor according to any one of claims 1 to 4, wherein the sensor body contacts the forehead, upper arm, back, or wrist of a human body.

6. The sensor according to any one of claims 1 to 5, wherein the enzyme layer contains at least one selected from lactate oxidase, glucose oxidase, and alcohol oxidase.

7. The sensor according to any one of claims 1 to 6, wherein the absorption layer includes a polymer material having a chemically bonded crosslinked structure, and the absorption layer covers the end faces of the enzyme layer and the electrode layer.

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