JP3907584B2 - Sugar detection electrode device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a sugar detection electrode device, and more particularly, a sugar detection electrode that maintains high sensitivity even when used for a long period of time in contact with blood, provides highly stable measurement values, and is easily sterilized and washed. Relates to the device.
[0002]
[Prior art]
Sugar analysis is carried out in a wide range of fields. For example, in the medical field, blood sugar concentration, that is, blood sugar level is measured.
[0003]
In the blood glucose level measurement, conventionally, a human invasive method of collecting blood from the fingertip and directly measuring the blood glucose level for each blood sample solution has been adopted, but this method requires continuous measurement. In addition, it has the disadvantage of causing pain and wounds to the patient.
[0004]
Therefore, a sugar detection device using current measurement using an electrode is being developed, and an enzyme sensor that can be incorporated into the sugar detection device has been proposed (Patent Document 1). In this sugar detection device, saliva or the like is used as a sample, an electrode is immersed in the sample solution, and the current generated when the sugar in the saliva reacts on the electrode is measured. The current generated by the reaction is measured, and the blood sugar level is determined from the relationship between the sugar concentration in saliva and the sugar concentration in blood.
[0005]
[Patent Document 1]
In the enzyme sensor as an example used in this type of conventional sugar detecting apparatus, for example, an enzyme film made of glucose oxidase and peroxidase is formed on a platinum electrode, and sugar is produced by these enzymes. Oxidize and measure the current generated at that time. According to this sugar detection apparatus, it is possible to perform continuous measurement while immersing the electrode in the sample solution, and since there is no need to collect blood, there is no pain for the patient.
[0006]
However, since this conventional sugar detection device uses an enzyme, the sensitivity decreases due to the fact that the enzyme is deactivated over time or the electrode is contaminated due to protein adhesion in the blood, etc. There was a drawback in that the value varied greatly, the measured value became unstable, and it could not be used for a long time.
[0007]
This conventional sugar detection device further has a drawback that cleaning is difficult because the enzyme film formed on the electrode is easily damaged by a mechanical external force.
[0008]
The sugar detector using the enzyme membrane has a drawback that it cannot be easily sterilized by a high pressure heating sterilization method and a gas sterilization method because the enzyme membrane has low durability against heat and pressure.
[0009]
[Problems to be solved by the invention]
An object of the present invention is to eliminate the above-described drawbacks of conventional sugar detection electrode devices. That is, an object of the present invention is to provide a sugar detection electrode device that can maintain high sensitivity over a long period of time as compared with an electrode using an enzyme membrane, can obtain a highly stable measurement value, and can be easily washed. It is.
[0010]
[Means for Solving the Problems]
As a means for solving the problem, the means according to claim 1 includes a counter electrode in a puncture body formed in an injection needle shape, and two insertion holes provided in a filler filled in the puncture body. A working electrode made of Ti - Ni alloy disposed so as to be movable back and forth in the direction along the axial direction in the insertion hole, and the insertion hole in the other insertion hole. A sugar detection electrode device comprising a reference electrode disposed so as to be movable back and forth in a direction along the axial direction in the inside ,
The means according to claim 2 can move back and forth in a direction along the axial direction of the counter electrode in the puncture body formed in the shape of an injection needle and the first tube disposed inside the puncture body. The working electrode made of Ti - Ni alloy and the second tube arranged outside the first tube and inside the puncture body are moved back and forth in the direction along the axial direction thereof. A sugar detection electrode device comprising a working electrode arranged to be movable ;
The means according to claim 3 includes : a counter electrode in a puncture body formed in an injection needle shape; an inner wall of an outer tube disposed inside the puncture body; and an outer wall of an inner tube disposed in the outer tube. Between the reference electrode and the working electrode made of Ti - Ni alloy , which is arranged so as to be movable back and forth in the direction along the axial direction of the outer tube, and the inside of the outer tube within arranged inside tube in its back and forth axial direction along the direction disposed so as to be movable in the reference electrode and Ti -; and a other of Ni alloy of the working electrode A sugar detection electrode device,
The means according to claim 4 is the sugar detection electrode device according to claim 1 , wherein the puncture body is formed by insulating the reference electrode and the working electrode with an insulating material filled therein.
The means according to claim 5 is the sugar detection electrode device according to any one of claims 1 to 4 , wherein the puncture body is formed to be bendable.
The sugar detection electrode device according to any one of claims 1 to 5 , wherein the puncture body is formed of a conductive material, and the puncture body itself forms a counter electrode. And
Means according to claim 7, wherein the puncture body is formed of a nonconductive material, the claim 1-6 any one of formed by a counter electrode is formed on the outer surface of the tip portion of the puncture body sugar detecting electrodes according to.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
The sugar detection electrode device according to the present invention, particularly the glucose detection electrode device, inputs an electrical measurement value measured at the electrode section and calculates the sugar concentration in the sample, particularly glucose, and displays it. With.
[0012]
As shown in FIG. 1, the electrode unit 10 includes a puncture body 11, a reference electrode 12, a working electrode 13, and a filler 14.
[0013]
The puncture body 11 is made of a conductive material and is formed into an injection needle shape. In other words, the puncture body 11 has a tip portion formed in a sharp bevel, and can be easily punctured, for example, in a blood vessel or the like. Therefore, the preferred puncture body 11 in the present invention has a size and dimensions that allow puncture of a blood vessel or the like. For example, the puncture body 11 can be formed with a diameter of about 1 to 0.1 mm. Of course, the diameter of this puncture body 11 can be made larger than the said range according to a use. Examples of the conductive material forming the puncture body 11 include metals such as stainless steel.
[0014]
The puncture body 11 further has a cylindrical shape, in which a reference electrode 12, a working electrode 13, and a filler 14 can be incorporated. The puncture body 11 formed of a conductive material also forms a counter electrode in the present invention. Therefore, the puncture body 11 in FIG. 1 is electrically coupled to the puncture body 11 and a measurement calculation unit described later via a conductive path such as a conductive line.
[0015]
The puncture body 11 is filled with a filler 14, and two insertion holes 15 and 16 are opened in the filler 14.
[0016]
The filler 14 may be an insulating material that can be easily processed. For example, synthetic resin such as curable epoxy resin and curable urethane resin, and synthetic rubber such as silicon rubber and styrene-butadiene rubber may be used. Can be mentioned. In the present invention, a liquid curable epoxy resin is particularly preferable for facilitating filling of the resin into the puncture body and from the viewpoint of safety.
[0017]
Of the two insertion holes provided in the filler 14, one of the insertion holes 15 has a core wire as the working electrode 13, and the distal end of the working electrode 13 slightly extends from the opening of the insertion hole 15. It is arranged so as to protrude or be exposed. As described above, when the tip of the working electrode 13 protrudes or is exposed from the opening of the insertion hole 15, the core wire as the working electrode 13 is slightly moved along its axis, thereby acting. The tip of the electrode 13 is brought into sliding contact with the edge of the opening of the insertion hole 15 so that the dirt adhering to the tip of the working electrode 13 can be easily removed. In other words, the outer diameter of the core wire as the working electrode 13 is slightly smaller than the inner diameter of the insertion hole 15 so that the core wire as the working electrode 13 can move back and forth in the direction along the axial direction in the insertion hole 15. Is preferably designed to be small.
[0018]
The working electrode 13 can be preferably made of a Ti—Ni alloy. The Ti—Ni alloy has a function of quantitatively oxidizing OH groups bonded to sugars such as glucose existing in blood. Therefore, since the material of the working electrode 13 is a Ti—Ni alloy, the working electrode 13 can come into contact with sugar in blood, oxidize the sugar, and generate a current corresponding to the sugar concentration.
[0019]
The composition of Ti and Ni in the Ti—Ni alloy is not particularly limited as long as the above functions are ensured. For example, the Ti content is 40 to 60% by mass with respect to the entire alloy, and the Ni content is 60 to 40%. Since the said function is exhibited effectively as it is the mass%, it is preferable.
[0020]
Of the two insertion holes, the other insertion hole 16 is provided with a core wire as the reference electrode 12 such that the tip of the reference electrode 12 slightly protrudes or is exposed from the opening of the insertion hole 16. It is installed. As described above, when the tip of the reference electrode 12 protrudes or is exposed from the opening of the insertion hole 16, the core wire as the reference electrode 12 is moved slightly along the axis, thereby making reference The tip of the electrode 12 can be brought into sliding contact with the edge of the opening of the insertion hole 16 to easily remove the dirt adhering to the tip of the reference electrode 12.
[0021]
The reference electrode 12 is not particularly limited as long as the potential of the working electrode 13 can be appropriately set, and a known reference electrode such as a Pd electrode, a platinum black electrode, a silver / silver chloride electrode, or the like can be used.
[0022]
The electrode portion in the present invention is not limited to the electrode portion 10 shown in FIG. 1, and various design changes can be made within the scope of the present invention.
[0023]
A puncture body 21 as shown in FIG. 2 can be employed instead of the puncture body 11 in the electrode section 10 shown in FIG.
[0024]
The puncture body 21 shown in FIG. 2 is formed of a non-conductive material such as hard plastic, particularly hard epoxy resin. Thus, when the puncture body 21 is formed of a non-conductive material, a conductive material such as metal foil, metal plating, carbon powder, carbon fiber, or carbon nanofiber is formed on the outer peripheral surface of the tip of the puncture body 21. The counter electrode 22 can be formed of a composite material containing a carbon material. The counter electrode 22 may be formed of a material that does not polarize itself as much as possible, as long as a current flowing in the direction opposite to that of the working electrode (not shown in FIG. 2) flows smoothly. The counter electrode forming material can be used.
[0025]
Further, the puncture body may be formed to be bendable by a conductive material or a non-conductive material. As the puncture body formed to be bendable, for example, a puncture body formed of a thermoplastic resin which is a bendable material, a puncture body main body having a bendable mechanical structure such as a bellows structure, and the puncture body thereof The puncture body etc. which are formed from the puncture body front-end | tip part couple | bonded with the front-end | tip of a main body can be mentioned. In any of the puncture bodies, it is desirable to form the counter electrode 22 on the outer peripheral surface of the puncture body as shown in FIG.
[0026]
Instead of the electrode part 10 shown in FIG. 1, the electrode part 30 shown in FIG. 3 can also be adopted.
[0027]
In the electrode portion 10 shown in FIG. 1, the working electrode 13 and the reference electrode 12 can be moved forward and backward along the axial direction in the two insertion holes 15 and 16, respectively, in the two insertion holes 15 and 16 in the filler 14. In the electrode portion 30 shown in FIG. 3, the two electrodes, the working electrode 13 and the reference electrode 12 are fixed by the filler 14 filled in the puncture body 11. In FIG. 3, the working electrode 13 and the tip of the reference electrode 12 are fixed so as to slightly protrude from the filler surface.
[0028]
The embodiment shown in FIG. 3 has the advantage that the stability of the measured value can be ensured by increasing the electrode surface area, and the electric saturation phenomenon due to liquid retention near the electrode is reduced.
[0029]
The electrode unit 40 shown in FIG. 4 can be employed instead of the electrode unit 10 shown in FIG.
[0030]
In FIG. 4, a first tube disposed inside the puncture body 11 and a second tube disposed outside the first tube and inside the puncture body 11 are provided. Inside the two tubes, a working electrode 13 is disposed on one side, and a reference electrode 12 is disposed on the other side.
[0031]
Also in FIG. 4, the tips of the working electrode 13 and the reference electrode 12 are formed to protrude from the tube. With such a configuration, the tip of the reference electrode 12 is slidably contacted with the edge of the opening of the insertion hole 16 by slightly moving the core wire as the reference electrode 12 along the axis. Thus, there is an advantage that dirt attached to the tip of the reference electrode 12 can be easily removed.
[0032]
In FIG. 5, an outer tube 51 disposed inside the puncture body 11 and an inner tube 52 disposed inside the outer tube 51. The inner tube 52 has one of a working electrode 53 and a reference electrode 54 inside, and the tube is either the working electrode 53 or the reference electrode 54 between the inner wall of the outer tube 51 and the outer wall of the inner tube. Or the other. The outer tube 51 and the puncture body 11 have a structure filled with an insulating material.
[0033]
FIG. 6 is a conceptual diagram showing a sugar detection electrode device 60, particularly a glucose detection electrode device, which is an example of the present invention. The sugar detection electrode device 60 includes a lead wire 66, a lead wire 67, a power source 68, a power source 69, and an ammeter 65. The lead wire 66 is provided with a power source 68 so that the counter electrode 63 serves as a cathode and the reference electrode 61 side serves as an anode. The lead wire 67 connects the counter electrode 63 and the working electrode 62. The lead wire 67 is provided with a power source 69 so that the counter electrode 63 side is a cathode and the working electrode 62 side is an anode. The lead wire 67 is provided with an ammeter 65. The ammeter 65 is connected to a measurement calculation unit that converts the measured current value into a sugar value.
[0034]
FIG. 7 is a conceptual diagram in which the puncture body 72 of the sugar detection electrode device 71 of the present invention is injected into a human blood vessel, and the sugar content in the blood is measured by the measurement calculation unit 73. The part to be punctured with the puncture body may be the upper arm or the abdomen, and is determined according to the handling of the patient in consideration of the condition of the patient.
[0035]
FIG. 8 is a correlation diagram between the integrated value of the current that flows when the puncture body of the sugar detection electrode device is injected and the glucose concentration 81. It can be seen that as the integrated value 82 of the current increases, the glucose concentration 81 also increases.
[0036]
【The invention's effect】
According to the sugar detection electrode device according to the present invention, since a Ti—Ni alloy is used for the working electrode, high-accuracy sugar detection, particularly glucose detection can be performed for a long period of time, and cleaning is easy.
[0037]
In the sugar detection electrode device according to the present invention, a Ti—Ni alloy is used for the working electrode. Therefore, in the conventional sugar detection electrode device using an enzyme for the working electrode, it is possible to avoid inactivation of the enzyme over time. Since it cannot be used, its lifetime is as short as several months. However, since it does not deteriorate over time like an enzyme, the sugar detection electrode device according to the present invention can be used for at least one year.
[0038]
Further, by disposing the working electrode and the reference electrode in the tube and bending the two electrodes protruding from the rear part of the puncture body, the tip part can be moved back and forth, and the dirt on the tip part can be removed.
[Brief description of the drawings]
FIG. 1 is a transverse cross-sectional view when an insertion hole of a sugar detection electrode device of the present invention is used as an axis.
FIG. 2 is a plan view of a sugar detection electrode device according to the present invention.
FIG. 3 is a vertical sectional view in the vertical direction when the insertion hole of the sugar detection electrode device of the present invention is used as an axis.
FIG. 4 is a cross-sectional view when the insertion hole of the sugar detection electrode device of the present invention is used as an axis.
FIG. 5 is a vertical cross-sectional view in the vertical direction when the insertion hole of the sugar detection electrode device of the present invention is used as an axis.
FIG. 6 is a conceptual diagram of a sugar detection electrode device according to the present invention.
FIG. 7 is a conceptual diagram for measuring current by injecting a sugar detection electrode device of the present invention into a blood vessel.
FIG. 8 is a correlation diagram between an integrated current value and a glucose concentration.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Electrode part 11 Puncture body, 12 Working electrode, 13 Reference electrode, 14 Filler,
15 insertion hole, 16 insertion hole, 20 electrode part, 21 puncture body,
22 counter electrode, 30 electrode part, 40 electrode part, 50 electrode part,
51 outer tube, 52 inner tube, 53 working electrode,
54 reference electrode, 55 filler, 60 sugar detection electrode device,
61 reference electrode, 62 working electrode, 63 counter electrode, 64 lead wire part,
65 ammeter, 65a measurement calculation unit, 66 lead wire, 67 lead wire,
68 power supply, 69 power supply, 71 sugar detection electrode device, 72 puncture body,
73 measurement calculation unit, 81 glucose concentration, 82 integral value of current,

Claims (7)

A counter electrode in the puncture body formed in the shape of an injection needle,
Of the two insertion holes provided in the filling material filled in the puncture body, Ti is disposed in one insertion hole so as to be movable back and forth in the direction along the axial direction within the insertion hole. - Ni alloy of the working electrode, and sugar to the other insertion hole, characterized in that it comprises a reference electrode disposed so as to be movable back and forth in the direction along the axis direction within the through hole Detection electrode device. A counter electrode in the puncture body formed in the shape of an injection needle ,
A working electrode made of a Ti — Ni alloy disposed so as to be movable back and forth in a direction along the axial direction in the first tube disposed inside the puncture body , and the first tube A sugar detection comprising: a working electrode disposed outside and in a second tube disposed inside the puncture body so as to be movable back and forth in a direction along an axial direction thereof. Electrode device. A counter electrode in the puncture body formed in the shape of an injection needle ,
Between the inner wall of the outer tube arranged inside the puncture body and the outer wall of the inner tube arranged inside the outer tube so as to be movable back and forth in the direction along the axial direction of the outer tube. It is possible to move back and forth in the direction along the axial direction of either the disposed reference electrode or the working electrode made of Ti - Ni alloy, and the inner tube disposed inside the outer tube. A sugar detection electrode device comprising : a reference electrode and a working electrode made of a Ti — Ni alloy , arranged in the manner described above . The sugar detection electrode device according to claim 1, wherein the puncture body is formed by insulating the reference electrode and the working electrode with an insulating material filled therein. The sugar detection electrode device according to any one of claims 1 to 4, wherein the puncture body is formed to be bendable. The sugar detection electrode device according to any one of claims 1 to 5, wherein the puncture body is formed of a conductive material, and the puncture body itself forms a counter electrode. The sugar detection electrode device according to any one of claims 1 to 6, wherein the puncture body is formed of a non-conductive material, and a counter electrode is formed on an outer surface of a tip portion of the puncture body.

Images