WO2001084133A1

WO2001084133A1 - Biosensor

Info

Publication number: WO2001084133A1
Application number: PCT/JP2001/003685
Authority: WO
Inventors: Shoji Miyazaki; Hiroyuki Tokunaga; Masaki Fujiwara; Eriko Yamanishi
Original assignee: Matsushita Electric Industrial Co., Ltd.
Priority date: 2000-04-27
Filing date: 2001-04-27
Publication date: 2001-11-08
Also published as: JP2001305093A; JP4061816B2

Abstract

A biosensor includes a cavity (8), through which liquid reagent is supplied by capillary action to an electrode part consisting of a measuring electrode (2) and an opposite electrode (3) on an insulating substrate and to a reagent layer (5) on the electrode part. The biosensor has a projection (10) on its side where an entrance (9) to the cavity is formed. The biosensor defines where to supply liquid sample and improves manipulability.

Description

Description Biosensor Technical Field

The present invention relates to a biosensor for analyzing a specific component in a liquid sample, and more particularly to a biosensor having a cavity for introducing a liquid sample by capillary action. Background art.

Conventionally, various biosensors have been proposed as a method for simply quantifying a specific component in a sample solution without diluting or stirring the sample solution. As an example of such a biosensor, a measurement electrode, a counter electrode, and a detection electrode made of an electrically conductive substance are formed on an insulating substrate such as polyethylene terephthalate. Some have a reagent layer containing an enzyme or the like that specifically reacts with a component.

In order to form a cavity in which the electrode detects a current value generated by a reaction between the reagent layer and the specific component in the sample liquid collected in an appropriate amount, a portion corresponding to the upper part of the electrode and the reagent layer And a cover having an air hole are stuck on the insulating substrate.

In the biosensor having such a configuration, the sample liquid is supplied into the cavity from the entrance of the cavity, which is the sample liquid suction port, by capillary action, and is guided to a position where the electrode and the reagent layer are present. On the electrode, a current value generated by a reaction between a specific component in the sample solution and a reagent contained in the reagent layer is read by connecting to an external measurement device through a lead, not shown here. .

However, in the conventional biosensor having the above-described configuration, the site for supplying the sample liquid (the entrance of the cavity) is unclear, so that it is difficult for the user to recognize, and especially, the inexperienced user ( (For example, this sensor is used for the first time.) There is a problem that a user mistakenly spots blood on the air hole, and the user tends to apply a sample liquid to the wrong part of the PY sensor, thereby causing measurement errors and measurement errors. there were. The present invention has been made to solve such a problem, and makes it easy for a user to recognize a portion to which a sample solution is to be supplied, and measures a measurement caused by a user spotting a sample solution on an incorrect portion. It aims to provide an excellent biosensor with few errors and measurement errors. Disclosure of the invention

The biosensor according to claim 1 of the present invention, wherein at least a measurement electrode formed on an insulating substrate, an electrode portion including a counter electrode, and a cavity to which a sample solution is supplied by a capillary phenomenon, A biosensor comprising: a reagent layer formed in a cavity; and a convex region or a concave region provided on a side surface of the biosensor. The sample liquid supply portion is provided in the convex region or the concave region. The entrance of the cavity is formed. '

As a result, it is possible to provide an excellent biosensor with few measurement errors and measurement errors, which makes it possible to clarify the sample liquid supply part and to easily recognize the sample liquid supply part.

Further, the biosensor according to claim 2 of the present invention is the biosensor according to claim 1, wherein the biosensor has a vertically long shape, The entrance of the cavity is formed. As a result, it is possible to provide a cavity entrance on the side surface where the user can easily supply the sample liquid, and to provide a biosensor excellent in user operability and having few measurement errors and measurement errors. ::.

Further, the biosensor according to claim 3 of the present invention is the biosensor according to claim 1, wherein the cavities are formed on the reagent layer disposed on the electrode unit. A spacer having a notch is attached thereto, and a cover is attached thereon.

This makes it possible to embody a cavity structure to which the sample liquid is supplied.

The biosensor according to claim 4 of the present invention is the biosensor according to claim 3, wherein the spacer is made of an opaque or translucent material. The force par is made of a transparent material.

As a result, the portion of the cavity to which the sample liquid is supplied is clarified, the user can easily recognize the sample liquid supply site, and there are few measurement errors and measurement errors, and an excellent pyrosensor can be provided. .

Further, since the supply state of the sample liquid can be visually checked, it is possible to provide an excellent pyrosensor with few measurement errors and measurement errors due to a shortage of the sample liquid. Further, the biosensor according to claim 5 of the present invention is the biosensor according to claim 1, wherein the cavity is a sample solution which is added to an inlet of the cavity. An air hole is provided to be supplied into the cavity by a phenomenon. Thus, the sample liquid supplied to the entrance of the cavity can be smoothly supplied into the cavity by capillary action.

Further, in the biosensor according to claim 6 of the present invention, in the biosensor according to claim 5, wherein the cavity is formed on the reagent layer disposed on the electrode unit. A spacer having a notch is attached thereto, and a force par is attached thereon, and the air hole is provided on a cover in contact with the cavity.

Thereby, the air holes can be made concrete, and the sample liquid supplied to the entrance of the cavity can be smoothly supplied into the T cavity by capillary action. .

The biosensor according to claim 7 of the present invention is the biosensor according to claim 5 or claim 6, wherein the shape of the air hole is a circle, an ellipse, or a triangle. , Square, rectangle, or polygon.

Thus, the sample liquid supplied to the entrance of the cavity can be smoothly supplied into the cavity by a capillary phenomenon.

Further, in the biosensor according to claim 8 of the present invention, in the biosensor according to claim 5 or claim 6, the air hole is formed at a position closest to an entrance of the cavity. It is formed at a position facing an end of the reagent layer at a remote position. As a result, diffusion of the reagent from the vicinity of the electrode after aspirating the sample liquid can be suppressed to a necessary minimum, and a highly accurate biosensor with less measurement variation can be provided. The biosensor according to claim 9 of the present invention is the biosensor according to claim 8, wherein the shape of the air hole is rectangular or square.

As a result, the amount of sample solution required to fill the cavity can be reduced, the diffusion of the reagent from the vicinity of the electrode is minimized, and a high-performance pyrosensor with little measurement variation is provided. Can be. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is an exploded perspective view showing a biosensor having a convex region according to the first embodiment of the present invention. .

FIG. 2 is an exploded perspective view showing the biosensor having a concave region according to the first embodiment of the present invention. BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1

Hereinafter, Embodiment 1 of the present invention will be described with reference to FIG. Embodiment 1 specifically describes an enzyme sensor using an enzyme as a molecular identification element that specifically reacts with a specific substance in a sample solution.

FIG. 1 is an exploded perspective view of a biosensor according to Embodiment 1 of the present invention. In FIG. 1, a measurement electrode 2, a counter electrode 3, and a detection electrode 4 made of an electrically conductive substance are formed on an insulating substrate 1.

The detection electrode 4 can be used not only as an electrode for detecting a shortage of a sample amount but also as a reference electrode or a part of the counter electrode 3.

First, preferred materials for the insulating substrate 1 include polyethylene terephthalate, polycarbonate, polyimide, and the like. Preferred examples of the electrically conductive substance for forming the electrodes include noble metals such as gold, platinum, and palladium, and carbon. Simple materials, or composite materials such as carbon paste and noble metal paste. In the case of the former, the electric conductive layer can be easily formed by a sputtering deposition method or the like, and in the case of the latter, the electric conductive layer can be easily formed by a screen printing method or the like. ::

The electrodes 2, 3, and 4 may be formed by forming the electrically conductive material on the entire surface or a part of the insulating substrate 1 by a sputtering method or a screen printing method, and then performing laser trimming or the like. The electrode can be divided and formed by providing a slit by using. Also, the electrodes can be formed in the same manner by a screen printing method using a printing plate on which an electrode pattern is formed in advance, a mask plate, a sputtering evaporation method, or the like.

On the electrodes 2, 3 and 4 thus formed, a reagent layer 5 containing an enzyme, an electron carrier and a hydrophilic polymer is formed as shown in FIG. 2, 3, 4 and on the reagent layer 5, laminating a spacer 6 having a notch, bonding the force per 7 having an air hole 1 1 thereon ^this: etc. Accordingly, the electrode及Pi reagent A cavity 8 for supplying the sample liquid to the layer 5 is formed. The reagent layer 5 may be placed on the entire surface of the electrodes 2, 3, and 4 or on a part thereof. In addition, any portion in contact with the cavity 8 may be used. -Here, the enzymes contained in the reagent layer 5 include glucose oxidase, lactate oxidase, cholesterol reoxidase, cholesterol monoolesterase, pericase, ascorbic acid oxidase, bilirubin oxidase, glucose dehydrogenase, Lactate todehydrogenase, etc. Use p-benzoquino other than potassium ferricyanide and its derivatives, phenazine methosulphate, methylene blue, phlegene and its derivatives as electron carriers in addition to potassium ferricyanide. Examples of hydrophilic polymers include carboxymethylcellulose, hydroxyxetinoresenorelose, hydroxypropinoresenorelose, methinoresenorelose, technoresenorelose, and etinoleshydroxenolose. Polyamino acids such as rerose, canoleboxymethylinoethyl cellulose, polybutyl alcohol, polybutylpyrrolidone, polylysine, polystyrene sulfonic acid, gelatin and its derivatives, acrylic acid and its salts, methacrylic acid and its salts, starch and Its derivatives, Maleic anhydride and its salts, agarose gel and its derivatives and the like can be used.

Suitable materials for the spacer 6 and the copper 7 include polyethylene terephthalate, polycarbonate, polyimide, polybutylene terephthalate, polyamide, polychlorinated vinyl, polychlorinated vinylidene, polyimide, and nylon. Can be

The biosensor of the present invention having the above configuration is significantly different from a conventional biosensor, in that a convex region 10 is provided on a part of the side surface of the biosensor, and the convex region 10 is provided in the convex region 10. This is because the entrance 9 of the cavity, which is the site for supplying the sample liquid, is made to come, which makes it easy for the user to recognize the location for supplying the sample liquid.

The shape of the region where the entrance 9 of the cavity is provided may be a shape other than a convex shape, for example, a concave shape as shown in FIG. 2, and in FIG. Reference numeral 5 denotes a recessed region in which the entrance 9 of the cavity is provided, and the same reference numerals as those in FIG. 1 denote the same or corresponding parts.

Further, the convex region 10 or the concave region 15 which is the region where the cavity entrance 9 is provided, reacts with the specific component in the sample solution added by the user and the reagent of the reagent layer 5. The sensor may be provided anywhere on the side surface of the biosensor as long as the current value as the measurement result can be obtained. As shown in the figure, the tip side surface in the longitudinal direction of the sensor is most preferable.

Further, when an opaque material or a translucent material is used for the material of the spacer 6 and a transparent material is used for the material of the force par 7 and the two are bonded together, only the cavity 8 of the pyrosensor becomes transparent, Provide an excellent biosensor with few measurement errors, since the inlet 9 of the cavity, which is the sample liquid supply part, is more clear, so that the user does not mistake the part that supplies the sample liquid (for example, whole blood). Can be done. In addition, since the cavity 8 is transparent, it is possible for the user to visually check the supply state of the sample liquid, and the measurement error of the Pyo sensor due to insufficient addition of the liquid to the sample liquid supply site Errors can be reduced. The opaque or translucent material of the spacer 6 is, for example, a colored resin film in which the material itself contains a pigment as a coloring agent, or a rubber film printed or dyed on the surface of the transparent resin film. It is possible to use a material that has been colored by the method described above.

When a sample liquid is supplied to the biosensor according to the first embodiment having such a configuration from the inlet 9 of the cavity, the sample liquid penetrates into the cavity 8 by capillary action, and is supplied to the electrode or the reagent layer 5. In order to allow the sample liquid to smoothly penetrate into the cavity 8, an air hole 11 for releasing air to the outside of the biosensor is required on the force par 7 facing the cavity 8.

The position of the air hole 11 may be any position in contact with the cavity 8 as long as the supply of the sample solution is not hindered.If the air hole 11 is too far from the reagent layer 5, The reagent diffuses in the vicinity of the electrode without the reagent layer 5, and the concentration of the required reagent on the electrodes 2, 3, and 4 becomes low, and the response value of the sensor tends to fluctuate. More preferably, 1 is at the same position as the rear part of the reagent layer 5 (the reagent layer 5 located farthest from the cavity entrance 9).

In addition, the shape of the air hole 11 can be a circle, an ellipse, a triangle, a square, a rectangle, a polygon, or the like. Even if any of the above-mentioned shapes is used, a smooth supply of the sample liquid is realized. However, if the shape of the air holes 11 is square or rectangular, the amount of the sample liquid required to fill the cavity 8 can be reduced, and the vicinity of the electrodes can be reduced. Thus, the diffusion of the reagent can be minimized.

In addition, the current value obtained by the reaction between the specific component in the sample solution and the reagent layer 5 containing the enzyme and the like is represented by the leads 12, 13, and 13 of the measurement electrode 2, counter electrode 3, and detection electrode 4. Through 14 it is connected to an external measuring device (not shown) and read.

In the current measurement, in addition to the three-electrode system consisting of the measuring electrode 2, the counter electrode 3 and the detection electrode 4 described in the first embodiment, there is a two-electrode system comprising only the measuring electrode and the counter electrode. Any method may be used to realize the effect obtained by the present invention. The three-electrode method can perform more accurate measurement.

As described above, according to the biosensor of the first embodiment, the user The cavity inlet 9 that supplies the sample liquid is provided with a convex area 10 that protrudes partially from the side of the sensor or a concave area 15 that depresses to make it easier for the user to recognize the sample supply area. It is easy for the user to operate, and measurement errors and measurement errors can be reduced.

Furthermore, by using an opaque material or a translucent material for the spacer 6 and using a transparent material for the cover 7, only the cavity 8 is made transparent, so that the sample liquid supply portion To provide a pyro sensor that allows the user to visually recognize the entrance 9 of a certain cavity or the cavity 8 itself, thereby making the user more aware of the site to which the sample is to be added and reducing measurement errors and measurement errors. be able to. Further, since the user can also check the sample supply state in the cavity 8, it is possible to provide a pyrosensor that can reduce measurement errors and measurement errors caused by an excessively small amount of the sample liquid to be added. In the above description, an example of an enzyme sensor was used. However, in addition to enzymes, biomolecules that use antibodies, microorganisms, DNA, RNA, etc. as molecular identification elements that specifically react with specific substances in the sample solution The sensor can be similarly configured. Industrial applicability

In the biosensor of the present invention, the sample liquid supply site can be clarified for the user by arranging the entrance of the cavity to which the sample liquid is supplied in the convex or concave area provided on the side surface of the biosensor. Useful for reducing errors and measurement errors.

Claims

The scope of the claims

1. At least a measurement electrode formed on an insulating substrate, and an electrode portion including a counter electrode;

A cavity in which the sample liquid is supplied by capillary action,

And a reagent layer disposed at a position facing the cavity.

A convex region or a concave region is provided on a side surface of the biosensor,

In the convex region or the concave region, an entrance of the cavity which is a supply portion of the sample liquid is formed.

A biosensor characterized in that:

2. In the biosensor according to claim 1,

The biosensor has a vertically long shape, and an entrance of the cavity is formed on a side surface of a longitudinal end thereof.

3. In the biosensor according to claim 1,

The cavity is formed by bonding a spacer having a notch on the reagent layer disposed on the electrode portion, and bonding a force bar on the spacer. Pyo sensor.

4. In the biosensor according to claim 3,

A biosensor, wherein the spacer is made of an opaque or translucent material, and the force par is made of a transparent material.

5. In the pyrosensor according to claim 1,

The biosensor according to claim 1, wherein the cavity has an air hole through which a sample liquid added to an entrance of the cavity is supplied into the cavity by a capillary phenomenon. "

6. In the pyrosensor according to claim 5,

The cavity is formed by bonding a spacer having a notch on the reagent layer disposed on the electrode portion, and bonding a force bar on the spacer, and the air hole includes: Being provided on a force par contacting the cavity, A biosensor characterized in that:

7. In the pyrosensor according to claim 5 or claim 6,

A biosensor, wherein the shape of the air hole is any one of a circle, an ellipse, a triangle, a square, a rectangle, and a polygon.

8. In the biosensor according to claim 5 or claim 6,

A biosensor, wherein the air hole is formed at a position facing an end of the reagent layer located farthest from an entrance of the cavity.

9. The biosensor according to claim 8, wherein

The shape of the said air hole is a rectangle or a square, The biosensor characterized by the above-mentioned.