KR20200120286A - Bio sensor - Google Patents

Abstract

The present invention relates to a biosensor with improved convenience and sensing performance. The biosensor of the exemplary embodiments of the present invention includes: a substrate; a first electrode including a protruding surface of a protruding shape; and a second electrode including a recessed surface of a recess shape. The area of the surface wherein the first electrode and the second electrode face each other increases, so that a sensing performance may be improved.

Description

Bio sensor {BIO SENSOR}

The present invention relates to a biosensor. More specifically, it relates to a biosensor capable of detecting the concentration of a substance to be detected.

As the life expectancy of humans increases, the healthcare industry is expanding rapidly. In particular, there is a growing demand for a portable small biosensor that can conveniently measure various bio-signals anywhere.

Conventional biosensors use enzymes that react with chemical species contained in body fluids (sweat, tears, blood, etc.). When the enzyme reacts with the chemical species to generate an electric current, it is measured to measure the concentration of the chemical species.

Most of the studies on biosensors are, for example, as disclosed in Korean Patent Publication No. 10-1107506, glucose oxidase or glucose dehydrogenase that promotes the oxidation of glucose to gluconolactone. It is based on the immobilization of enzymes such as enzymes.

To drive the biosensor, a predetermined amount of sample must be supplied to the sensor electrode. The larger the minimum sample requirement of the sensor, the more difficult it is to obtain a corresponding amount of sample (eg, sweat or blood).

Korean Registered Patent Publication No. 10-1107506

An object of the present invention is to provide a biosensor with improved convenience and sensing performance.

1. a substrate; A first electrode disposed on the substrate and including a protruding surface having a shape protruding in one direction parallel to the substrate; A biosensor comprising a second electrode on the substrate that faces and is spaced apart from the first electrode and includes a recess surface having a recess shape for receiving the protruding shape of the protruding surface.

2. The biosensor according to the above 1, wherein the protruding shape of the first electrode defines a protrusion, and the recess shape of the second electrode defines a recess.

3. The biosensor according to the above 1, wherein the protruding shape is formed in a central area of the protruding surface.

4. The biosensor according to the above 1, wherein the protruding surface and the recessed surface have a curved shape.

5. The biosensor according to the above 1, wherein the spaced apart space between the protruding surface and the recessed surface defines a channel portion, and the channel portion has a constant width.

6. In the above 5, the central portion of the channel portion is provided as a sensing area, the biosensor,

7. The biosensor according to the above 1, wherein the protruding shape of the protruding surface and the recess shape of the recessed surface are in a complementary relationship.

8. In the above 1, a side surface opposite to the protruding surface of the first electrode defines a first opposite surface, a side surface opposite to the recess surface of the second electrode defines a second opposite surface, and 1 opposite surface and the second opposite surface have a seamless (seamless) curved shape, the biosensor.

9. The biosensor according to the above 8, wherein the distance between the recessed surface and the second opposite surface of the second electrode is constant.

10. The biosensor according to the above 1, wherein the first electrode and the second electrode define a sensing electrode, and the total width of the sensing electrode is 0.3 to 5 mm.

11. The biosensor according to the above 10, comprising a plurality of sensing electrodes arranged on the substrate, the sensing electrodes sensing different sensing target materials.

12. The biosensor according to the above 1, further comprising a first wiring electrically connected to the first electrode and a second wiring connected to the second electrode.

13. The biosensor according to the above 1, wherein one of the first electrode and the second electrode is provided as a working electrode, and the other of the first electrode and the second electrode is provided as a reference electrode.

14. In the above 13, the working electrode, the conductive layer disposed on the substrate; An electron transport layer disposed on the conductive layer; And an enzyme reaction layer disposed on the electron transport layer.

15. In the above 14, the enzyme reaction layer is at least one of glucose oxidase, cholesterol oxidase, lactate oxidase, ascorbic acid oxidase, and alcohol oxidase, or glucose dehydrogenase, glutamic acid dehydrogenase, lactate A biosensor comprising at least one of dehydrogenase and alcohol dehydrogenase.

16. The biosensor according to the above 14, wherein the electron transport layer includes Prussian blue.

17. The biosensor according to the above 14, wherein the conductive layer includes a metal layer and a metal protective layer.

18. In the above 17, the metal layer includes at least one of Au, Ag, Cu, Pt, Ti, Ni, Sn, Mo, Co, Pd, and alloys thereof, and the metal protective layer is ITO (Indium Tin Oxide ) Or IZO (Indium Zinc Oxide) containing, a biosensor.

19. The biosensor according to the above 14, wherein the working electrode further comprises a filter layer disposed on the enzyme reaction layer.

According to exemplary embodiments of the present invention, the first electrode and the second electrode are disposed to face each other, and the opposite surfaces have a protruding shape and a recess shape, respectively. In this case, the protruding shape may be accommodated in the recess shape to increase the area of the facing surface compared to the total size of the sensing electrode. Therefore, it is possible to reduce the minimum sample requirement and improve sensing sensitivity and speed.

According to exemplary embodiments, a protruding shape of the protruding surface and a recess shape of the recessed surface may have a complementary relationship. In this case, the area of the facing surface may be increased relative to the total area of the sensing electrode.

1 is a schematic plan view of a biosensor according to exemplary embodiments.
2 is a schematic plan view of a sensing electrode according to exemplary embodiments.
3 is a schematic plan view of a sensing electrode according to a comparative example.
4 is a schematic cross-sectional view of a sensing electrode according to exemplary embodiments.

Exemplary embodiments of the present invention provide a biosensor including a substrate, a first electrode including a protruding surface having a protruding shape, and a second electrode including a recess surface having a recess shape. The area of the surface where the first electrode and the second electrode face each other increases, so that the sensing performance may be improved.

1 is a schematic plan view of a biosensor according to exemplary embodiments.

Referring to FIG. 1, a biosensor 10 according to exemplary embodiments includes a substrate 100, a first electrode 110, a second electrode 120, and a wiring 140. In addition, an auxiliary sensor 130 may be further included.

The substrate 100 is provided as a base layer on which the first electrode 110, the second electrode 120, the wiring 140 and/or the auxiliary sensor 130 are disposed.

For example, the substrate 100 may be a base film having flexible properties, and specific examples include polyester resins such as polyethylene terephthalate, polyethylene isophthalate, polyethylene naphthalate, and polybutylene terephthalate; Cellulose resins such as diacetyl cellulose and triacetyl cellulose; Polycarbonate resin; Acrylic resins such as polymethyl (meth)acrylate and polyethyl (meth)acrylate; Styrene resins such as polystyrene and acrylonitrile-styrene copolymer; Polyolefin resins such as polyethylene, polypropylene, polyolefin having a cyclo-based or norbornene structure, and ethylene-propylene copolymer; Vinyl chloride resin; Amide resins such as nylon and aromatic polyamide; Imide resin; Polyethersulfone resin; Sulfone resin; Polyether ether ketone resin; Sulfide polyphenylene resin; Vinyl alcohol resin; Vinylidene chloride resin; Vinyl butyral resin; Allylate resin; Polyoxymethylene resin; A film composed of a thermoplastic resin such as an epoxy resin may be mentioned, and a film composed of a blend of the thermoplastic resin may also be used. In addition, a film made of a thermosetting resin such as (meth)acrylic, urethane, acrylic urethane, epoxy, silicone, or an ultraviolet curable resin may be used.

The thickness of the substrate 100 may be appropriately determined, but may be 1 to 500 μm in consideration of strength, handling, workability, and thin layer properties. It is preferably 1 to 300 µm, and more preferably 5 to 200 µm.

For example, the base film may contain one or more additives. Examples of the additives include ultraviolet absorbers, antioxidants, lubricants, plasticizers, release agents, colorants, flame retardants, nucleating agents, antistatic agents, pigments, colorants, and the like.

In some embodiments, the base film may include various functional layers such as a hard coating layer, an antireflection layer, and a gas barrier layer on one or both sides of the film.

In some embodiments, the base film may be surface-treated. For example, the surface treatment may include chemical treatment such as plasma treatment, corona treatment, dry treatment such as primer treatment, and alkali treatment including saponification treatment.

The sensing electrode may be formed on the substrate 100. The sensing electrodes may include a first electrode 110 and a second electrode 120 facing each other and spaced apart from each other. According to some embodiments, the first electrode 110 and the second electrode 120 may be disposed to face left and right.

Therefore, when a sample is supplied between the first electrode 110 and the second electrode 120, the sample is formed of electrons/holes and oxidation-reduction materials between the first electrode 110 and the second electrode 120. Movement can be mediated. Therefore, it is possible to drive the biosensor 10 with a small amount of sample.

2 is a schematic plan view of a sensing electrode according to exemplary embodiments.

Referring to FIG. 2, the first electrode 110 may include a protruding surface 112, and the second electrode 120 may include a recess surface 122.

The protruding surface 112 may be defined as a surface facing the second electrode 120 of the side surfaces of the first electrode 110. The protruding surface 112 may have a shape protruding in one direction parallel to the substrate 100. In some embodiments, the protruding surface 112 may protrude in the second direction. For example, a profile viewed from a top view of the protruding surface 112 may have a shape protruding in the second direction. The protruding portion defined by the protruding surface 112 of the first electrode 110 may be provided as the protruding portion 114.

In the present specification, the'first direction' may mean a direction in which sensing electrodes extend from the wires (eg, a length direction). The'second direction' may mean a direction in which the first electrode and the second electrode face each other (eg, a width direction of sensing electrodes). The'third direction' may mean the thickness direction of the biosensor and sensing electrodes.

In example embodiments, the protruding shape may be formed in a central region of the protruding surface 112. The central region may mean a region covering the center of the length of the first electrode 110.

In example embodiments, the first electrode 110 may have an ax blade shape. In this case, a portion to which the ax handle of the ax blade is coupled may be provided as the protrusion 114.

The recess surface 122 may be defined as a surface facing the first electrode 110 among side surfaces of the second electrode 120. The recessed surface 122 may have a recessed shape that accommodates the protruding shape of the protruding surface 112. For example, a region of the protruding surface 112 of the recess surface 122 corresponding to the position at which the protruding shape is formed may have a concave shape. A recess portion 124 into which the protrusion portion 114 of the first electrode 110 is inserted may be formed in the second electrode 120 by the recess surface 122.

In this case, the protruding shape of the protruding surface 112 may be at least partially accommodated in the recess shape of the recess surface 122. Accordingly, an area facing the protruding surface 112 and the recess surface 122 may be increased compared to the size of the sensing electrodes (the first electrode 110 and the second electrode 120 ).

In example embodiments, the recess shape may be formed substantially all over the recess surface 122.

In some embodiments, the second electrode 120 may have a'C' shape. In this case, the protrusion 114 of the first electrode 110 may be accommodated in the'C'-shaped concave portion. In some embodiments, the'C' shape may include a left and right inverted'C' shape.

For example, two surfaces of the first electrode 110 and the second electrode 120 facing each other may be defined as a protruding surface 112 and a recess surface 122, respectively. The protruding surface 112 of the first electrode 110 and the recessed surface 122 of the second electrode 120 may be spaced apart from each other to face left and right.

In example embodiments, the protruding surface 112 and/or the recessed surface 122 may have a curved shape. For example, a profile viewed from a plan view of the protruding surface 112 and/or the recess surface 122 may have a curved shape.

In this case, an area facing the protruding surface 112 and the recess surface 122 may be increased compared to the lengths of the protruding surface 112 and the recess surface 122. The lengths of the protruding surface 112 and the recess surface 122 may mean the lengths of the long sides of the protruding surface 112 and the recess surface 122. Accordingly, the sensing performance for the sensing target material may be improved.

In addition, the sample may flow smoothly along the curved shape. In this case, even if a small amount of the sample is used, the sample may evenly fill the space between the first electrode 110 and the second electrode 120. Accordingly, the minimum amount of sample required to drive the biosensor 10 can be reduced.

For example, the protruding surface 112 and/or the recess surface 122 may have the curved shape as a whole.

When the protruding surface 112 and the recess surface 122 have a protruding shape and a recess shape, respectively, the area of the surface facing the first electrode 110 and the second electrode 120 is compared to the size of the sensing electrode. Can increase.

In example embodiments, the protruding surface 112 may include one of the protruding shapes. For example, the protrusion 114 may be formed alone. In this case, the recess shape of the recess surface 122 and the recess portion 124 may also be formed alone.

In example embodiments, a space facing the first electrode 110 and the second electrode 120 and spaced apart from each other may define a channel portion. For example, the channel portion may include a space spaced apart between the protruding surface 112 and the recess surface 122. The channel portion may penetrate the sensing electrode in a longitudinal direction (first direction). A sample may be filled in the channel portion, and movement of a compound such as a sensing target material and a reaction product may be mediated between the first electrode 110 and the second electrode 120 by the sample.

In example embodiments, the channel portion may have a substantially constant width. The width of the channel portion may mean the shortest distance between the protruding surface 112 and the recess surface 122. The'substantially constant' may include a change within ±5% in addition to the mathematical change. In this case, the fluidity of the sample may be improved within the channel part. Accordingly, the sample may be evenly distributed in the channel part, and a wider area of the first electrode 110 and the second electrode 120 may be used for the electrochemical reaction.

In example embodiments, the central portion of the channel portion may be provided as a sensing area. The sensing region may mean a region having relatively excellent sensing performance (eg, sensitivity and speed). The central portion may mean a region covering the central portion of the length of the channel portion (length in the first direction). For example, it may mean a region in which the protrusions 114 are formed.

In example embodiments, the protruding surface 112 and the recess surface 122 may have substantially the same length. The lengths of the protruding surface 112 and the recessed surface 122 may mean the length of the curved profile. The'substantially identical' may include not only mathematical equality, but also a change within ±5%.

In example embodiments, the protruded shape of the protruding surface 112 and the recessed shape of the recessed surface 122 may have a complementary relationship. The term “complementary relationship” used in the present specification may mean that when two shapes are attached, they are substantially integrated without an empty space, and may include a case including a predetermined tolerance. For example, when the first electrode 110 and the second electrode 120 shown in FIG. 2 are connected together, an integrated circle or ellipse may be formed. When the complementary relationship is satisfied, an area facing the sensing electrode may increase.

In example embodiments, one of the side surfaces of the first electrode 110 opposite to the protruding surface 112 may be provided as the first opposite surface 116. Among the side surfaces of the second electrode 120, a side opposite to the recess surface 122 may be provided as a second opposite surface 126. The first opposite surface 116 and/or the second opposite surface 126 may have a curved shape without irregularities. The curved shape without irregularities may be, for example, a seamless shape.

In some embodiments, a distance between the recess surface 122 and the second opposite surface 126 of the second electrode 120 may be substantially constant. In this case, the shape of the recess of the second electrode 120 may be enlarged, and the amount of accommodating the protrusion 114 of the first electrode 110 may be increased.

In some embodiments, the first opposite surface 116 and the second opposite surface 126 may have a semicircular profile. In this case, the sensing electrode including the first electrode 110 and the second electrode 120 may be substantially circular or elliptical. Accordingly, when a sample droplet is provided to the sensing electrode, the shape of the droplet and the sensing electrode are similar, so that the sensing performance of the biosensor 10 may be improved.

In example embodiments, the first electrode 110 and the second electrode 120 may define a sensing electrode. The sensing electrode may include a pair of opposing first electrodes 110 and second electrodes 120 and spaced apart spaces therebetween (eg, the channel portion).

The term “the total width of the sensing electrode” as used herein may mean a distance between the two farthest points of the first electrode 110 and the second electrode 120.

In example embodiments, the total width of the sensing electrode may be 0.3 to 5 mm. When the total width is less than 0.3mm, the amount of an electric signal (current) generated when measuring the sensing target material decreases, and thus the sensitivity, the measurement speed, and/or the maximum measurement concentration of the biosensor may decrease. When the total width exceeds 5 mm, the minimum amount of sample required for driving the sensing electrode may increase.

In some embodiments, the minimum sample requirement of the biosensor 10 may be 0.1 to 1 μl. For example, when the total width of the sensing electrode is 0.3 to 5 mm, the biosensor 10 may be driven with a sample of about 1 μl or less.

In example embodiments, the biosensor 10 may include a plurality of the sensing electrodes. Each of the sensing electrodes may detect different sensing target materials or the same sensing target materials.

3 is a schematic plan view of a sensing electrode according to a comparative example.

Referring to FIG. 3, the sensing electrode of the comparative example includes a working electrode 210 and a reference electrode 220, and may be connected to a first wiring 242 and a second wiring 244, respectively.

The sensing electrode of the comparative example may have a structure in which the reference electrode 220 surrounds the working electrode 210. In this case, a sample of an amount capable of covering the working electrode 210 and the reference electrode 220 together may be required to drive the sensor. Accordingly, the minimum amount of sample required for driving the sensor can be increased.

In addition, when the size of the working electrode 210 of the comparative example is matched with the size of the first electrode 110 of the embodiment, the overall size of the sensing electrode of the comparative example may increase. Accordingly, the minimum sample required amount for covering the working electrode 210 and the reference electrode 220 may increase. When the overall size of the sensing electrode of the comparative example is matched with the overall size of the sensing electrode of the embodiment, the size of the working electrode 210 of the comparative example may be smaller than the size of the first electrode 110 of the embodiment. Accordingly, the sensitivity, maximum measurement concentration, and sensing speed of the sensor may be reduced.

The wiring 140 may be connected to the sensing electrode. The wiring 140 may include a first wiring 142 connected to the first electrode 110 and a second wiring 144 connected to the second electrode 120. In addition, a third wiring 146 connected to the auxiliary sensor 130 may be included.

The auxiliary sensor 130 may include a heat sensor, a pH sensor, and/or a humidity sensor. For example, the auxiliary sensor 130 may measure temperature, pH and/or humidity to correct a measurement error of the biosensor 10.

In exemplary embodiments, one of the first electrode 110 and the second electrode 120 is provided as a working electrode, and the other of the first electrode 110 and the second electrode 120 is provided as a reference electrode Can be.

For example, the first electrode 110 may be provided as a working electrode of the sensing electrode, and the second electrode 120 may be provided as a reference electrode of the sensing electrode. In some embodiments, the first electrode 110 may be provided as a reference electrode of the sensing electrode, and the second electrode 120 may be provided as a working electrode of the sensing electrode.

4 is a schematic cross-sectional view of a sensing electrode according to exemplary embodiments.

Referring to FIG. 4, the sensing electrode may include a working electrode 310 and a reference electrode 320 disposed on the substrate 100.

The working electrode 310 may include a conductive layer 312, an electron transport layer 314 and an enzyme reaction layer 316. In addition, a filter layer 318 may be further included. The conductive layer 312 may include a metal layer 312a and a metal protective layer 312b. The reference electrode 320 may include a second conductive layer 322 and a reference material layer 324.

In the working electrode 310, an oxidation-reduction reaction of a sensing target material (measurement target material) may occur. The working electrode 310 may detect an electrical signal generated by the reaction of the target material included in the sample. The sample may be sweat, body fluid, tears, blood, etc., but is not limited thereto.

For example, the sensing target material may include glucose or lactic acid (lactate).

The conductive layer 312 may be disposed on the substrate 100. The conductive layer 312 may be provided as a path through which electrons or holes generated in an oxidation-reduction reaction of a material to be sensed are transferred.

In example embodiments, the conductive layer 312 may include a metal layer 312a and a metal protective layer 312b.

The metal protective layer 312b may entirely cover the upper surface of the metal layer 312a. For example, the metal protection layer 312b may directly contact the metal layer 312a. The metal protective layer 312b may prevent oxidation-reduction of the metal layer 312a due to an oxidation-reduction reaction.

In example embodiments, the metal layer 312a may include at least one of Au, Ag, Cu, Pt, Ti, Ni, Sn, Mo, Co, Pd, and alloys thereof. For example, an APC (Ag-Pd-Cu) alloy may be used. The metal layer 312a may be formed of only at least one of Au, Ag, APC alloy, and Pt. The Au, Ag, APC alloy, and Pt may improve electrical conductivity of the conductive layer 312 and reduce resistance. Accordingly, it is possible to improve the detection performance of the biosensor 10.

In example embodiments, the metal protective layer 312b may include Indium Tin Oxide (ITO) or Indium Zinc Oxide (IZO). For example, the metal protective layer 312b may be formed of only ITO or IZO. ITO and IZO have electrical conductivity and are chemically stable, so that the metal layer 312a can be effectively protected from an oxidation-reduction reaction.

For example, the metal protective layer 312b may prevent the metal layer 312a from directly contacting the atmosphere, thereby preventing oxidation of a metal component constituting the metal layer 312a. Accordingly, reliability of an electrical signal sensed by the metal layer 312a may be improved.

The electron transport layer 314 may be disposed on the conductive layer 312. For example, the conductive layer 312 may be directly covered.

The electron transport layer 314 may provide an electron/hole movement path for transferring electrons or holes generated in the oxidation-reduction reaction to the conductive layer 312.

The electron transport layer 314 may include an electron transport material. The electron transport material may include, for example, a material that is oxidized or reduced by receiving electrons/holes generated in an oxidation-reduction reaction of a substance to be detected in the enzyme reaction layer 316. Electrons/holes may be transferred through the oxidation or reduction.

In example embodiments, the electron transport material may include Prussian blue. Prussian blue is a blue pigment whose main component is potassium hexacyano iron (II) iron (III) acid, and may have high oxidation properties. When Prussian blue is disposed on the conductive layer 312, the electrical sensitivity of the working electrode 310 may be improved.

In some embodiments, the electron transport layer 314 may further include carbon paste.

The enzyme reaction layer 316 may be disposed on the electron transport layer 314. For example, it may directly contact the upper surface of the electron transport layer 314.

The enzyme reaction layer 316 may be provided as a layer in which a chemical reaction of a substance to be detected included in the sample occurs. The enzyme reaction layer 316 may include an oxidative enzyme or a dehydrogenase that reacts with a substance to be detected.

In exemplary embodiments, the oxidative enzyme is the enzyme reaction layer 316 is glucose oxidase, cholesterol oxidase, lactate oxidase, and ascorbic acid oxidase. acid oxidase) and alcohol oxidase. The dehydrogenase may include at least one of glucose dehydrogenase, glutamate dehydrogenase, lactate dehydronase, and alcohol dehydrogenase.

Therefore, the concentration of glucose, cholesterol, lactate, ascorbic acid, alcohol or glutamic acid can be measured.

For example, when the biosensor 10 is a glucose sensor, the enzyme reaction layer 316 may include glucose oxidase or glucose dehydrogenase.

In some embodiments, the oxidative enzyme or the dehydrogenase may be immobilized through a binder. The binder may include a binder commonly used in the art, and may include, for example, chitosan.

For example, when a sample is injected into the biosensor 10, a detection target material included in the sample is oxidized by an oxidase or dehydrogenase, and hydrogen peroxide may be formed. The electron transport material (for example, Prussian blue) reduces hydrogen peroxide, and itself can be oxidized. The oxidized electron transport material loses electrons at the electrode surface to which a certain voltage is applied and can be electrochemically oxidized again.

Since the concentration of the object to be detected in the sample is proportional to the amount of current generated in the process of oxidizing the electron transporting substance, the concentration of the object to be detected can be measured by measuring the amount of current.

The filter layer 318 may be disposed on the enzyme reaction layer 316. For example, it may be directly covered on the upper surface of the enzyme reaction layer 316.

The filter layer 318 may protect the enzyme reaction layer 316 from external physical forces. Further, it is possible to prevent the oxidative enzyme or dehydrogenase of the enzyme reaction layer 316 from being exposed to the external environment.

The filter layer 318 may pass only the material to be detected in the sample. Accordingly, it is possible to prevent the enzyme reaction layer 316 from being denatured or damaged by materials other than the material to be detected.

If the filter layer 318 passes a material to be sensed, an ion exchange membrane commonly used in the art may be used. The ion exchange membrane may include a cation exchange resin such as a perfluorosulfonic acid resin. For example, the ion exchange membrane may include Nafion.

According to exemplary embodiments of the present invention, a conductive layer 312 is formed on the substrate 100, an electron transport layer 314 is formed on the conductive layer 312, and an enzyme is formed on the electron transport layer 314. By forming the reaction layer 316, the working electrode 310 can be manufactured.

The conductive layer 312 forms a metal film including at least one of Au, Ag, Cu, Pt, Ti, Ni, Sn, Mo, Co, Pd, and alloys thereof on the substrate 100, and then patterning ( It can be formed by patterning).

For the patterning, a patterning method commonly used in the art may be used. For example, photolithography can be used.

When the conductive layer 312 further includes a metal protective layer 312b, the metal layer 312a is first patterned and then a metal protective layer 312b is formed, or ITO (Indium Tin Oxide) or IZO is formed on the metal layer. After the (Indium Zinc Oxide) conductive oxide layer is formed, the metal layer 312a and the metal protective layer 312b may be formed together by patterning the metal layer and the conductive oxide layer together.

In example embodiments, the electron transport layer 314 may be formed by applying a mixture of an electron transport material and a carbon paste on the conductive layer 312.

For the coating, a coating method commonly used in the art may be used, and for example, various printing methods may be used.

The enzyme reaction layer 316 may be formed by, for example, applying a composition obtained by mixing the oxidative enzyme or the dehydrogenase with a binder on the electron transport layer 314 and then drying it.

The reference electrode 320 may be disposed on the substrate 100 to face the working electrode 310 left and right. The reference electrode 320 and the working electrode 310 may be electrically separated. The reference electrode 320 may be provided as a counter electrode for an oxidation-reduction reaction.

The reference electrode 320 may provide a reference value for a current value or a potential value measured by the working electrode 310 during measurement. Using the potential value of the reference electrode 320 as a reference value, an oxidation-reduction reaction of the material to be sensed occurring in the working electrode 310 may be specified. In addition, by comparing the reference value of the current value and the current value measured by the working electrode 310, the amount of current purely changed by the sensing target material may be calculated. Accordingly, the concentration of the material to be detected can be derived from the amount of current.

The second conductive layer 322 of the reference electrode 320 may include substantially the same material as the conductive layer 312 of the working electrode 310. In addition, a reference material layer 324 may be disposed on the second conductive layer 322 instead of the electron transport layer 314. For example, the reference electrode 320 may be formed by stacking the second conductive layer 322 and the reference material layer 324 on the substrate 100.

The reference material layer 324 may include, for example, Ag/AgCl paste.

In some embodiments, the wiring 140 may be connected to the first electrode 110 and the second electrode 120, respectively. The first wiring 142 connected to the first electrode 110 and the second wiring 144 connected to the second electrode 120 may be electrically spaced apart from each other. The wirings 140 may be connected to a driving integrated circuit (IC) chip. For example, the first wiring 142 may be connected to the working electrode 310, and the second wiring 144 may be connected to the reference electrode 320.

For example, the wiring 140 may be formed of the same material as the metal layer 312a of the working electrode 310 and the second conductive layer 322 of the reference electrode 320. In some embodiments, the wiring 140 may be integrally formed with the working electrode 310 and the reference electrode 320. For example, by forming a metal film on the substrate 100 and patterning it, the sensing electrode and the wiring 140 may be formed together.

Electrical signals measured from the first and second electrodes 110 and 120 may be transmitted to the driving IC chip through the wiring 140, and the driving IC chip may calculate the concentration of the component to be measured.

10: biosensor
100: substrate
110: first electrode 112: protruding surface
114: protrusion 116: first opposite surface
120: second electrode 122: recess surface
124: recess portion 126: second opposite surface
310: working electrode
312: conductive layer 314: electron transport layer
316: enzyme reaction layer 318: filter layer
320: reference electrode
322: second conductive layer 324: reference material layer
130: auxiliary sensor 140: wiring
20: sensing electrode of a comparative example

Claims (19)

Board;
A first electrode disposed on the substrate and including a protruding surface having a shape protruding in one direction parallel to the substrate;
A biosensor comprising a second electrode on the substrate that faces and is spaced apart from the first electrode and includes a recess surface having a recess shape for receiving the protruding shape of the protruding surface.
The biosensor of claim 1, wherein the protruding shape of the first electrode defines a protrusion, and the recess shape of the second electrode defines a recess.
The biosensor of claim 1, wherein the protruding shape is formed in a central area of the protruding surface.
The biosensor of claim 1, wherein the protruding surface and the recessed surface have a curved shape.
The biosensor of claim 1, wherein a spaced apart space between the protruding surface and the recess surface defines a channel portion, and the channel portion has a constant width.
The biosensor of claim 5, wherein the central portion of the channel portion is provided as a sensing area,
The biosensor of claim 1, wherein the protruding shape of the protruding surface and the recess shape of the recessed surface are in a complementary relationship.
The method according to claim 1, wherein a side opposite to the protruding surface of the first electrode defines a first opposite surface, and a side opposite to the recess surface of the second electrode defines a second opposite surface,
The first opposite surface and the second opposite surface have a seamless (seamless) curved surface shape, the biosensor.
The biosensor of claim 8, wherein a distance between the recessed surface and the second opposite surface of the second electrode is constant.
The biosensor of claim 1, wherein the first electrode and the second electrode define a sensing electrode, and the total width of the sensing electrode is 0.3 to 5 mm.
The biosensor according to claim 10, comprising a plurality of the sensing electrodes arranged on the substrate, the sensing electrodes sensing different sensing target materials.
The biosensor of claim 1, further comprising a first wire electrically connected to the first electrode and a second wire connected to the second electrode.
The biosensor of claim 1, wherein one of the first electrode and the second electrode is provided as a working electrode, and the other of the first electrode and the second electrode is provided as a reference electrode.
The method of claim 13, wherein the working electrode,
A conductive layer disposed on the substrate;
An electron transport layer disposed on the conductive layer; And
A biosensor comprising an enzyme reaction layer disposed on the electron transport layer.
The method of claim 14, wherein the enzyme reaction layer is at least one of glucose oxidase, cholesterol oxidase, lactate oxidase, ascorbic acid oxidase, and alcohol oxidase, or glucose dehydrogenase, glutamic acid dehydrogenase, lactate dehydrogenase. And at least one dehydrogenase of alcohol dehydrogenase.
The biosensor according to claim 14, wherein the electron transport layer comprises Prussian blue.
The biosensor of claim 14, wherein the conductive layer comprises a metal layer and a metal protective layer.
The method of claim 17, wherein the metal layer comprises at least one of Au, Ag, Cu, Pt, Ti, Ni, Sn, Mo, Co, Pd, and alloys thereof, and the metal protective layer is ITO (Indium Tin Oxide) or A biosensor containing Indium Zinc Oxide (IZO).
The biosensor of claim 14, wherein the working electrode further comprises a filter layer disposed on the enzyme reaction layer.

Images