JP2007232628A - Biosensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a biosensor capable of specifying accurately a sample volume by simple constitution, and capable of restraining dispersion of a coefficient of variation (CV). <P>SOLUTION: In this biosensor, leads are formed on two sheets of electrical insulating substrates, a working electrode and a counter electrode of same shape are provided in the respective substrates to contact with one part of the reed at a thickness thicker than the lead, and the two sheets of electrical insulating substrates are bonded via a spacer to oppose the working electrode to the counter electrode. The biosensor has an excellent effect to specify accurately the sample volume by the simple constitution, since the measuring sample volume is specified by a space between the opposed working electrode and counter electrode. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a biosensor. More specifically, the present invention relates to a biosensor that electrochemically measures component concentrations of various liquids using an enzyme or the like.

As a conventional disposable biosensor, a mechanism is known in which a three-dimensional structure is taken in order to ensure quantitativeness, and a sample solution is automatically introduced into the sensor using a capillary phenomenon or the like. Here, the electrode area is generally defined by an insulating layer in order to suppress fluctuations in measured values due to differences in electrode area.
Japanese Patent Laid-Open No. 1-291153

  In addition, a sensor having such a structure is assembled by stacking a spacer and a cover on an electrically insulating substrate, and further, an electrode pattern is formed on the substrate, and air necessary for capillary action is released on the cover. It is necessary to provide necessary air holes, and these components must be previously punched into a predetermined shape. Further, since positioning for accurate superimposition of each part in the three-dimensional processing is necessary, the three-dimensional processing process becomes complicated as the number of components increases.

  As described above, the conventional sensor is often used for manufacturing such as formation of an insulating layer on the electrode for suppressing fluctuations in measured values, formation of an air port for smooth capillary action, and alignment during substrate lamination. As a result, a large amount of capital investment was required for the production line, the yield of the product was not sufficient, and the cost was high. Naturally, the environmental load at the time of material procurement and manufacturing was also large.

  An object of the present invention is to provide a biosensor capable of accurately defining a sample volume with a simple configuration and suppressing variation in coefficient of variation (CV).

  The object of the present invention is to form a lead on two electrically insulating substrates and provide a working electrode and a counter electrode of the same shape on each substrate to be thicker than the lead so as to be in contact with a part of the lead. This is achieved by a biosensor in which two insulating substrates are bonded via a spacer so that the working electrode and the counter electrode face each other.

  The biosensor of the present invention has an excellent effect that the sample volume can be accurately defined with a simple configuration because the measurement sample volume is defined by the opposing working electrode and counter electrode. By accurately defining the measurement sample volume, variation in the coefficient of variation (CV) of the biosensor can be suppressed.Therefore, a biosensor array can be formed by providing multiple working and counter electrodes as a biosensor configuration, and multiple samples can be formed. It is also possible to simultaneously measure multiple items and the same item.

  As the substrate, it is sufficient if it is electrically insulating, for example, plastic, biodegradable material, paper or the like is used, and preferably polyethylene terephthalate is used.

  Leads are formed on the electrically insulating substrate. Each lead is formed on each of the two electrically insulating substrates so that one end thereof serves as a terminal connected to the measuring apparatus. The lead material is not particularly limited as long as it is conductive, and the same material as the electrode material described later can be used. For example, carbon, silver, silver / silver chloride, platinum, gold, nickel, copper, palladium, Examples include titanium, iridium, lead, tin oxide, and platinum black. Here, as the carbon, carbon nanotubes, carbon microcoils, carbon nanohorns, fullerenes, dendrimers, or derivatives thereof can be used. The lead made of a conductive material is formed by a screen printing method, a vapor deposition method, a sputtering method, a foil attaching method, a plating method, or the like.

  The electrode is formed in contact with a part of the lead. As an aspect which contacts a part of lead, what formed the electrode so that the edge part on the opposite side to the lead edge part which forms a terminal may be mentioned, for example. Since the electrode is in contact with the lead, it is possible to apply a voltage to the electrode and output a response current value from the electrode to the measuring device. As the electrode material, the same materials as exemplified in the lead are used.

  In such an electrode, the working electrode and the counter electrode are formed in the same shape on each substrate. By making the working electrode and the counter electrode have the same shape and arranging them facing each other at the time of forming the biosensor, it is possible to provide an excellent effect that the volume of the measurement sample solution can be defined by the electrode area and the distance between the electrodes. Accordingly, it is not necessary to form a resist layer, which is conventionally required for defining the electrode area, and it is possible to provide a biosensor with a simpler configuration and a small variation coefficient (CV value). In addition, by using the facing electrode, the electrochemical reaction proceeds efficiently, and the volume of the reaction layer can be effectively reduced to a small amount. As a result, the number of samples can be reduced.

  Here, the electrode is provided thicker than the lead thickness. Specifically, it has a thickness of 1 to 100 μm, preferably 3 to 20 μm, and is formed by a method appropriately selected from methods according to the thickness, for example, a screen printing method, a vapor deposition method, a sputtering method, a foil attaching method, a plating method, and the like. Is done. When the electrode is provided thinner than the lead thickness, the measurement sample solution wraps around the lead, making it difficult to define the volume of the measurement sample solution based on the electrode area and the distance between the electrodes.

  The electrode may be a two-pole method formed by a working electrode and a counter electrode or a three-pole method formed by a working electrode and a counter electrode, a reference electrode, or an electrode method having more poles. Here, when the three-pole method is adopted, in addition to the electrochemical measurement of the measurement target substance, it is possible to measure the moving speed of the blood sample introduced into the conveyance path, thereby measuring the hematocrit value. Further, it may be composed of two or more electrode systems. In this case, a biosensor array can also be constructed.

  A reagent layer (electrode reaction part) is formed on the substrate on which the electrodes are formed, if necessary. The reagent layer is formed by a screen printing method or a dispenser method, and the reagent layer can be immobilized on the electrode surface or the substrate surface by an adsorption method involving drying or a covalent bonding method. The reagent layer is preferably formed by purification before formation. Examples of the purification method include a filtration method using a membrane and the like, and impurities are removed by purification. Reagents include enzymes, antibodies, nucleic acids, primers, peptide nucleic acids, nucleic acid probes, microorganisms, organelles, receptors, cell tissues, molecular identifiers such as crown ether, mediators such as potassium ferricyanide, ferrocene, benzoquinone, intercalators, coenzymes , Antibody labeling substances, substrates, inorganic salts such as sodium chloride and potassium chloride, surfactants, and lipids can be contained. Further, the enzyme includes an enzyme such as oxidase or dehydrogenase, such as glucose oxidase, fructosylamine oxidase, lactate oxidase, urate oxidase, cholesterol oxidase, alcohol oxidase, glutamate oxidase, pyruvate oxidase, glucose dehydrogenase, lactate dehydrogenase, alcohol dehydrogenase, In addition, at least one of cholesterol esterase, protease, and DNA polymerase can be used.

  Examples of the reagent disposed in the electrode reaction part of the biosensor include those containing glucose oxidase as an oxidase and potassium ferricyanide as a mediator when configured for blood glucose measurement. When the reagent is dissolved by the blood, the enzyme reaction is started. As a result, potassium ferricyanide coexisting in the reaction layer is reduced and potassium ferrocyanide, which is a reduced electron carrier, is accumulated. The amount is proportional to the substrate concentration, ie the glucose concentration in the blood. The reduced electron carrier accumulated for a certain time is oxidized by an electrochemical reaction. An electronic circuit in the main body of the measuring apparatus, which will be described later, calculates and determines the glucose concentration (blood glucose level) from the anode current measured at this time, and displays it on the display unit arranged on the main body surface.

  Other examples of reagent layers include combinations of inorganic salts and quinhydrone, primer, DNA polymerase and deoxyribonucleotide triphosphate, primer, DNA polymerase, deoxyribonucleotide triphosphate, sodium chloride, potassium chloride, etc. Examples include combinations of inorganic salts and quinhydrone.

  In addition, a surfactant and a lipid can be applied around the measurement sample inlet, which will be described later, and on the surface of the electrode or reagent layer (electrode reaction part). By applying a surfactant or lipid, the measurement sample solution can be moved smoothly.

  The two substrates on which the electrodes are formed are bonded with an adhesive. Accordingly, an adhesive layer is formed on one or both of the two insulating substrates. The adhesive is not particularly limited as long as it does not react or dissolve with the substrate. For example, an acrylic resin adhesive, preferably a thermosetting resin or a photocurable resin, more preferably visible light. A curable acrylic resin is mentioned. Such an adhesive layer can also be formed by a screen printing method, and has a thickness capable of forming an interelectrode distance of 3 to 498 (about 500) μm between the working electrode and the counter electrode, that is, about 5 to 500 μm, preferably Is formed with a thickness of about 10-100 μm. Thus, in the biosensor according to the present invention, the adhesive layer has an important function as a spacer in addition to the role of bonding the electrically insulating substrates together.

  The two electrically insulating substrates on which the electrodes are formed are bonded to each other so that the electrodes face each other after an adhesive layer is formed, thereby forming a biosensor.

  In forming a biosensor, in order to accurately superimpose two electrically insulating substrates, it is preferable that one substrate has at least one position determining recess and the other substrate has at least one position determining protrusion, preferably two or more. , Provided together with or in place of the adhesive layer. By fitting such position determining irregularities to form a biosensor, it is possible to easily and accurately superimpose two electrically insulating substrates. Moreover, it can also have a role as a spacer together with the adhesive layer, and the distance between the electrodes can be accurately defined by the position determining convex portion. When the distance between the electrodes is defined by the position determining convex portion instead of the adhesive layer, the maximum distance can be set to 1.5 mm. Here, with respect to the convex portion, it is only necessary that the protruding portion at the tip fits into the concave portion of the concave portion. For the concave portion, even if the sample introduction hole is provided directly on the substrate, the concave member is attached to the substrate surface. The aspect provided in may be sufficient. By providing a positioning recess, the two substrates can be bonded to each other without the need for a particularly precise alignment compared to the conventional lamination method. Furthermore, according to this method, only the adhesive is used as a spacer. Compared with the case where it has been, it has the characteristic that control of thickness can be prescribed | regulated also by the length of a convex part.

  In addition, a biosensor as a folded molded body can be formed by connecting two electrically insulating substrates by a connecting portion and folding the two electrically insulating substrates along the connecting portion. In the case of a biosensor that is such a folded molded body, a connecting portion as a folding line is provided so as to be horizontal in the long axis direction of a long substrate, and further, an electrode or the like is formed and then folded along the connecting portion. After that, a large number of biosensors can be manufactured at once by punching into the sensor shape. The biosensor produced by such a production method has very good reproducibility and has features that cannot be achieved by the conventional lamination method.

  The length of the connecting portion is equal to or greater than the thickness of the adhesive layer, that is, 0.5 to 5 mm, width 0.2 to 2.5 mm, preferably length 1.0 to 4 mm, and width 0.5 to 1.5 mm. At least two or more places are provided between the substrates. If such a connection part has a length of about 0.5 to 0.9 mm on the insulating substrate, for example, it is a gear-shaped thin disk whose convex part is a blade, as a broken line The connection portion formed and having a length of about 1 to 5 mm is hinge-molded by punching an insulating substrate with a mold. Accordingly, the two insulating substrates in this case refer to each of the substrates that are formed with a connecting portion formed on one insulating substrate, with the result that the connecting portion is formed as a boundary. Here, by making the length of the connection part 0.5mm or more, the need to fix the folded part by thermocompression bonding or using a fixture is reduced, especially about 1 to 4mm in length and 0.5 to 1.5mm in width. In the case of a connecting portion having a length of, it is not necessary to prevent the warping by fixing the folded portion by thermocompression bonding or using a fixing tool. In addition, as the length of the connecting portion is increased, the accuracy during folding may be slightly deteriorated. In such a case, the alignment of the two insulating substrates should be performed using the alignment uneven portion. Thus, such a problem can be avoided. In the case of a folded biosensor, since the two substrates are connected by the connection portion, the positioning effect can be sufficiently exhibited by providing one position determining uneven portion.

  In the biosensor having the above-described configuration, the measurement sample solution sent from the sample introduction port is filled between the working electrode and the counter electrode. For example, the reaction caused by the measurement sample solution coming into contact with the reagent layer on the electrode Monitored as an electrical change.

  Furthermore, the biosensors of the present invention can be used in an array. For example, when a biosensor is used as a DNA chip, it is preferable to fix the nucleic acid probe as a sample layer and arrange the biosensor in an array.

  In the present invention, the volume of the measurement sample is defined by the measurement sample liquid filled between the working electrode and the counter electrode, but in order to more strictly define the measurement sample volume, it is fixed using a dispenser or pipette. A volume of sample solution can also be fed into the electrode reaction layer. In such a case, it is preferable to provide a sample introduction hole for introducing the measurement sample solution into either the working electrode or the counter electrode. The sample introduction hole penetrates the electrode and the electrically insulating substrate. When the reagent layer is provided on the working electrode, it is preferably provided on the counter electrode side.

  As a measuring device for a biosensor, a device that is easy to carry and secures operability and durability so that measurement using a biosensor can be repeatedly and reliably performed is used. Specific configurations include a sensor introduction part, a connector, an electrochemical measurement circuit, a memory part, an operation panel, a measurement part for measuring electrical values in the electrodes of the biosensor, and a display part for displaying the measurement values in the measurement part In addition, a radio wave such as Bluetooth (registered trademark) can be mounted as a wireless means.

  The measurement device must have voice guidance and voice recognition functions for visual impairment due to diabetes, measurement data management function with built-in radio clock, communication function for medical data such as measurement data, and charging function. Can do.

  A measurement method in the measurement unit of the measurement apparatus is not particularly limited, and potential step chronoamperometry, coulometry, cyclic voltammetry, or the like can be used.

As described above, the needle-integrated biosensor of the present invention does not limit the user, that is, can handle a universal project.

  Next, biosensors according to embodiments of the present invention will be described in detail with reference to the drawings. However, the present invention is not limited to the following examples unless it exceeds the gist.

  FIG. 1 is a view showing an assembly example of a biosensor according to the present invention. a) shows the side of the electrically insulating substrate 1 that forms the outside when the biosensor is formed, and marks 25 are provided on the upper and lower sides, respectively. b) shows the side of the electrically insulating substrate 1 that forms the interior when the biosensor is formed. Leads 7 are provided on the upper and lower surfaces. As shown in c), a working electrode and a counter electrode are respectively provided at the end of the lead to form electrodes 10 and 10. Further, as shown in d), the reagent layer 13 is provided on one surface thereof, and the adhesive layer 5 is provided in the central portion of the lead. Since the adhesive layer 5 is thick, it also functions as the spacer 2. e) shows a biosensor 3 formed of a folded molded body 18 formed by folding d) with the connecting portion 21 as a boundary. Here, the terminal 11 is provided at the upper part, and the sample inlet 12 is provided at the opposite lower tip. This A-A 'cross section is shown in f). As can be seen from this figure, the distance between the electrodes is defined by the thickness of the adhesive layer 5 inside the folded molded body 18 formed by folding the substrate 1. Further, the distance between the two electrodes facing each other is closer to the substrate by the thickness. By adopting such a structure, the sample liquid can penetrate between the two electrodes by surface tension. Other than the electrodes, for example, the substrate portion cannot reach the sample liquid because the distance between the substrates is larger than the distance between the electrodes. Here, the mark 25 is provided as a guide when inserting the tip of the sensor into the sample solution.

  FIG. 2 is a diagram showing an example of use of the biosensor shown in FIG. As shown to a), the sample liquid 24 in this case has shown the case where it exists abundantly compared with the required measurement sample volume of the sensor 3. FIG. When the biosensor is immersed in the sample solution up to the mark 25 provided as a guideline for immersing the sensor 3 in the sample solution 24, the sample solution 24 uses the surface tension of the sensor 3 as shown in b). It is introduced into the space 26 between the electrodes 10 and 10. When the sensor is quickly lifted from the sample solution as shown in c) in this state, the sample solution 24 is held between the two electrodes 10 and 10 as shown in d). Here, the sample solution shows the case of a large amount of sample in which the tip of the sensor chip is soaked. However, if the sample volume required for the sensor, that is, the volume between the working electrode and the counter electrode is satisfied, the sample amount is about the size of a water drop. Can be measured.

  FIG. 3 shows the biosensor shown in FIG. 1 in which a position determining convex portion 31 is provided on one substrate and at least one position determining concave portion 32 is provided on the other substrate. By fitting such position determining irregularities to form a biosensor, it is possible to easily and accurately superimpose two electrically insulating substrates. Moreover, it can also have a role as a spacer together with the adhesive layer, and the distance between the electrodes can be accurately defined by the position determining convex portion 31. By providing the position determining recess 32, the two substrates can be bonded together without the need for a particularly accurate alignment as compared with the conventional laminating method. According to this method, only the adhesive is used as a spacer. Compared to the case where it was used, it is possible to avoid a situation in which the thickness slightly changes depending on the blending method such as the adhesive solvent, so that the thickness control can be accurately defined by the length of the convex portion 31, and the sample There is a feature that strict definition of volume is possible.

  FIG. 4 shows a biosensor in which the substrate of the biosensor shown in FIG. 1 is not connected by a connecting portion, and two position determining irregularities are provided instead of the adhesive layer. By providing the positioning uneven portions at two locations, a more accurate inter-substrate distance can be defined, so that the sample volume can be strictly defined. Furthermore, it is possible to construct a stacked type biosensor that is not limited only to the distance between the substrates but has a very simple configuration including only the cover portion and the substrate portion and does not require strict positioning.

  FIG. 5 is a view showing another assembly example of the biosensor according to the present invention. In a), electrically insulating substrates 1 and 1 are shown, and one substrate is provided with a sample introduction hole 4. In b), leads 7 and 7 are formed on the surfaces of the electrically insulating substrates 1 and 1, and one lead is provided so as not to block the sample introduction hole 4 provided in the substrate. In c), electrodes 10 and 10 are provided at the end portions of these leads, respectively, and one of the electrodes is provided so as not to block the sample introduction hole 4 provided in the substrate like the lead. A reagent layer 13 'is formed on one electrode surface. Further, an adhesive layer 5 is provided at the center of the lead. Since the adhesive layer 5 is thick, it also functions as the spacer 2. d) shows a biosensor 3 consisting of a folded molded body 18 formed by folding c) with the connecting portion 21 as a boundary. Here, the terminal 11 is provided in the lower part, and the sample inlet 12 is provided in the upper part on the opposite side.

  FIG. 6 shows an example of use of the biosensor shown in FIG. The AA ′ and BB ′ cross sections shown in a) are shown in a) ii) and iii), respectively. In a) ii), the adhesive layer 5 maintains the distance between the folded substrates 1 and 1 as a spacer 2, and a sample introduction hole 4 is provided in the upper part of the two substrates, which is the sample introduction. It has a mouth 12. The sample solution introduced from here fills the space between the upper and lower electrodes 10, 10 by surface tension as shown in b) ii) and iii).

  FIG. 7 is a view showing still another assembly example of the biosensor according to the present invention. A significant difference from FIG. 5 is that two adhesive layers 5 are provided so as to sandwich the electrode 10 therebetween. e) is a cross-sectional view taken along the line AA ′ shown in d). The adhesive layer 2 is provided above and below the electrode reaction part 13 so that the structure can be kept stable.

  FIG. 8 is a view showing an assembly example of the biosensor array according to the present invention having two or more sets of electrode systems. The folding biosensor having the facing electrode structure having the fitting mechanism shown in FIG. 3 is an array. It is arranged in a shape. Here, the sensors are connected to each other by the insulating substrate 1 for forming the upper and lower sensor terminal portions 11 in order to form the array 35. a) shows a developed view before folding, and b) shows a completed biosensor array after folding.

  FIG. 9 shows the biosensor array 35 shown in FIG. 8b) arranged in 10 rows and a connector array connected to them. Here, the connector array 34 has 20 connectors 11 per row, and two connectors are connected to the two terminal portions of each sensor 3, respectively. Here, since the terminals 11 of the sensor 3 are arranged inside the two plates and do not contact the adjacent sensor terminals 11 facing each other, each terminal 11 of the connector array 34 is connected to the sensor terminal 11. Needs to be sandwiched between two plates. As a result, the connector array 34 and the biosensor array 35 have a feature that can also serve to physically fix the biosensor array 35 to the connector array 34 in addition to electrical connection.

  FIG. 10 shows an example of use of the sensor array 35 connected to the connector array 34. a) in a state before the sample liquid 24 is introduced into the sensor array 35 connected to the connector array 34, b) in a state in which the sample liquid 24 is introduced, and in c) after the sample liquid 24 is introduced. Indicates the state. By adopting such a configuration, for example, by forming the sample liquid array 38 on a plane using a dispenser or the like, a plurality of measurements can be performed at one time. Examples of applications include quantification of various components contained in the same blood, and simultaneous measurement of multiple items such as genetic diagnosis by single nucleotide polymorphism.

Further, in this embodiment, when forming the sample solution array 38, the sample solution is not a well-like (concave) array, but has a feature that simultaneous measurement of multiple items is possible only by spreading it into a flat plate shape. ing. As a treatment method to spread the sample solution in a flat plate shape and keep it in one place,
1) A sample solution having a high affinity with the solvent of the sample solution is provided on the sample solution arrangement portion on the flat plate.
2) A convex part is provided on the flat plate, and the top of the part is used as a sample liquid arrangement part.
3) A convex portion smaller than the diameter of the sample liquid is provided on the flat plate, and the sample liquid is formed by covering the entire convex portion with the sample liquid. Is difficult to move and the distance between the electrodes is made narrower than the head of the convex portion, so that the sample liquid is introduced in contact with the head of the convex portion.
Etc.

  FIG. 11 is a diagram showing another assembly example of the biosensor array according to the present invention having two or more sets of electrode systems. As shown in a), there are two electrically insulating substrates 1, 1, and the electrode forming insulating substrate 1 shown in the upper part has a through-hole serving as a position determining recess 32 between both ends of the substrate and each sensor. Is provided. The lower substrate 1 is formed with a lead 7 for forming a terminal 11 and an electrode 10 on one end portion of the lead 7 as in the upper substrate, and a position determining convex portion 31 is provided between both ends of the substrate and each sensor. It has been. b) shows a state in which each convex portion 31 is accurately fitted in accordance with the definition of the concave portion 32 so that the two insulating substrates 1 and 1 have a facing electrode structure. A side view of this assembly process is shown in c) i) and ii). FIG. 3d shows stepwise how the sample liquid 24 is introduced into the sensor in the AA ′ cross-sectional view shown in FIG. Here, the structure in which the electrode 10 structures formed on the surfaces of the substrate 1 and the leads 7 with a thickness equal to or larger than the leads are opposed to each other, so that the introduction of the sample solution 24 is smoothly performed only between the electrodes. It shows what is happening.

  FIG. 12 shows a biosensor array formed by connecting two insulating substrates of the biosensor array shown in FIG. 11 by a connecting portion and folding it. As shown in a), the two insulating substrates are connected to each other by the connecting portion 21. A biosensor array 35 formed by folding this is shown in b). A side view of this assembly process is shown in c) i) and ii). FIG. 3d shows stepwise how the sample liquid 24 is introduced into the sensor in the AA ′ cross-sectional view shown in FIG. Here, a state is shown in which the sample liquid 24 is smoothly introduced between the electrodes 10 and 10 with the same configuration as in FIG.

  FIG. 13 shows the folding biosensor array shown in FIG. 12 arranged in 8 rows. FIG. 12A shows a state in which eight biosensor arrays 35 shown in FIG. 12 are arranged in parallel, and a plate material serving as the spacer 2 is sandwiched between the arrays. b) shows a state in which the connector array 34 is similarly connected to the biosensor array of 8 rows and 12 columns formed in this way. c) i) is an AA ′ cross-sectional view of the biosensor array shown in b), and c) ii) shows a state in which the connector array 34 is connected to the terminal 11 portion of each sensor. With this configuration, it is possible to perform measurement with the same number of samples as the 96-hole multi-item simultaneous measurement apparatus.

  FIG. 14 is a view showing still another assembly example of the biosensor array according to the present invention having two or more electrode systems. a) shows a substrate 1 provided with a sample introduction hole 4 serving as a sample introduction port at the center of each of ten donut-shaped electrodes 10. One end of the lead 7 on the substrate 1 is in contact with the electrode 10, and the other end forms a terminal 11. b) i) shows a substrate 1 provided with an adhesive layer 5 which also serves as a spacer 2 on the surface, and 10) a substrate 1 shown in b) ii) provided on the surface. The biosensor electrode array 35 shown in c) is manufactured by facing each of the electrodes.

  FIG. 15 shows an example of use of the biosensor array shown in FIG. In i), ten electrodes 10 are arranged on the substrate 1 so as to face the electrodes 10 provided on the facing substrate 1, and each biosensor electrode is partitioned by the adhesive layer 5. One electrode 10 is provided with a sample introduction hole 4 serving as a sample introduction port 12. In ii), an array-like sample solution injector 30 is disposed in the sample introduction port 12. In iii), a sample solution is provided. 24 shows a state in which it is injected. In iv), the state in which the injected sample solution 24 is maintained at a surface tension that works only between the electrodes 10 and 10 provided above and below is shown.

  FIG. 16 shows a biosensor array in which positioning unevenness portions are provided on two insulating substrates of the biosensor array shown in FIG. It is a figure which shows the other assembly example of the biosensor array based on this invention which has two or more sets of electrode systems. By providing the position determining irregularities, an accurate inter-substrate distance can be defined as compared with the case where only the adhesive layer is formed, so that the sample volume can be strictly defined. Furthermore, it is possible to construct a stacked type biosensor array that is not limited only to the inter-substrate distance but has a very simple configuration including only the cover portion and the substrate portion and does not require strict positioning.

  FIG. 17 is a diagram showing an assembly example of the biosensor array shown in FIG. a) shows electrically insulating substrates 1 and 1 on which electrodes and leads are formed. One substrate is provided with a sample introduction hole, and the other substrate is provided with an alignment protrusion 31. It is shown. The convex part 31 also acts as a spacer. The convex portion 31 is fitted with many concave portions 32 provided in the substrate 1 shown in b), so that the two substrates overlap without requiring special alignment, thereby defining the distance between the substrates.

  FIG. 18 shows an example in which the two electrically insulating substrates 1 and 1 of the sensor array 35 shown in FIG. 16 are connected by a connecting portion. Due to the presence of the connecting portion 21, the positioning of the fitting portion is further facilitated.

  FIG. 19 shows a sensor array 35 of 5 rows and 10 columns formed by arranging five sensor arrays 35 shown in FIG. 16 in parallel. Also here, there is a feature that the use of the connecting portion 21 enables accurate and smooth stacking of plate materials having a wide area. Further, by using such a sensor array 35, multiple items of a plurality of samples and simultaneous measurement of the same items can be performed.

  The biosensor (array) according to the present invention is a home-use self-diagnosis blood glucose meter, urine sugar meter, glycated hemoglobin meter, and lactic acid meter that electrochemically measures the component concentrations of various liquids using enzymes and the like. Cholesterol meter, uric acid meter, protein meter, single nucleotide polymorphism sensor, DNA chip used for genetic diagnosis, alcohol meter, glutamic acid meter, pyruvic acid meter, pH meter, etc.

It is a figure which shows one assembly example of the biosensor which concerns on this invention. It is a figure which shows one usage example of the biosensor which concerns on this invention. It is a figure which shows one assembly example of the biosensor which concerns on this invention provided with the position determination uneven | corrugated | grooved part. It is a figure which shows one assembly example of the biosensor which concerns on this invention provided with two position determination uneven | corrugated | grooved parts. It is a figure which shows the other assembly example of the biosensor which provided the sample introduction hole based on this invention. An example of use of a biosensor according to the present invention provided with a sample introduction hole will be described. It is a figure which shows the other assembly example of the biosensor which provided the sample introduction hole based on this invention. It is a figure which shows one assembly example of the biosensor array which concerns on this invention. It is a figure which shows 10 biosensor arrays shown in FIG. 8, and a connector array connected to these. It is a figure which shows one usage example of the biosensor array shown in FIG. It is a figure which shows one assembly example of the biosensor array which concerns on this invention provided with the position determination uneven | corrugated | grooved part. It is a figure which shows the other assembly example of the biosensor array shown in FIG. It is a figure which shows eight biosensor arrays shown in FIG. 12, and a connector array connected to these. It is a figure which shows the other assembly example of the biosensor array which concerns on this invention. It is a figure which shows one usage example of the biosensor array shown in FIG. It is a figure which shows the other assembly example of the biosensor array which concerns on this invention provided with the positioning uneven | corrugated | grooved part. It is a figure which shows one assembly example of the biosensor array shown in FIG. It is a figure which shows the other assembly example of the biosensor array which concerns on this invention provided with the positioning uneven | corrugated | grooved part. It is a figure which shows the further assembly example of the biosensor array which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Insulating substrate 2 Spacer 3 Biosensor 4 Sample introduction hole 5 Adhesive layer 7 Lead 10 Electrode 11 Terminal 12 Sample introduction port 13 Electrode reaction part 13 'Reagent layer 18 Folding molding 21 Connection part 24 Sample liquid 25 Mark 26 Space 30 Sample solution injector 31 Convex part 32 Concave part 34 Connector array 35 Biosensor array 38 Sample liquid array

Claims (11)

  Leads are formed on two electrically insulating substrates, and each substrate is provided with a working electrode and a counter electrode having the same shape thicker than the leads so as to be in contact with a part of the leads. A biosensor in which two insulating substrates are bonded to each other through a spacer so as to face each other.   The biosensor according to claim 1, wherein the working electrode and the counter electrode have a thickness of 1 to 100 µm.   The biosensor according to claim 1, wherein a sample introduction hole that penetrates the electrode and the electrically insulating substrate for introducing the sample liquid is provided in either the working electrode or the counter electrode.   The biosensor according to claim 1, wherein the sample volume can be defined by introducing the sample liquid into a space formed by the working electrode and the counter electrode facing each other.   The biosensor according to claim 1, wherein one end of the conductor serves as a connection terminal connected to an external measuring device in order to electrically measure the characteristics of the sample solution.   The biosensor according to claim 1, wherein a position determination concave portion is provided on one substrate and at least one position determination convex portion is provided on the other substrate in order to indicate an overlapping position of the two electrically insulating substrates.   The biosensor according to claim 1, wherein the distance between the two electrically insulating substrates is 3 to 1500 µm.   The biosensor according to claim 1, wherein a distance between the two electrically insulating substrates is determined by a spacer.   The biosensor according to claim 1, wherein the spacer is formed of an adhesive layer or a positioning convexity.   The biosensor according to claim 1, wherein the two insulating substrates are connected by a connecting portion, and the two insulating substrates are folded along the connecting portion. The biosensor array according to any one of claims 1 to 10, comprising a plurality of working electrodes and counter electrodes.

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