KR20190045064A - Biosensor resistant to coffee ring effect - Google Patents

Abstract

A biosensor robust against a coffee ring effect is disclosed. The biosensor robust against the coffee ring effect includes: a substrate; a work electrode and a reference electrode patterned on one surface of the substrate; a reactive material layer applied to the one surface of the substrate such that one portion thereof is layered on one part of the work electrode, and another portion thereof is layered on one part of the reference electrode; and a film layer, which is layered on the one surface of the substrate and has a slot having a predetermined width and extending such that the reactive material layer is exposed, wherein each of the work electrode and the reference electrode includes: a terminal part positioned in an external area of the slot; a reaction part positioned in an internal area of the slot, having a predetermined width, extending in the widthwise direction of the slot at a predetermined length, and having both longitudinal ends, respectively spaced apart from slot side walls, which face each other in the widthwise direction of the slot, at a predetermined interval; and a connection part having a width narrower than that of the reaction part, and extending from the reaction part to be connected to the terminal portion.

Description

[0001] The present invention relates to a biosensor resistant to coffee ring effect,

This application is a priority claim based on Korean Patent Application No. 10-2017-0137669 filed on October 23, 2017, the disclosure of which is incorporated herein by reference in its entirety.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrochemical biosensor, and more particularly, to an electrochemical biosensor having a characteristic strong against a coffee ring effect generated when a reaction material for causing an electrochemical reaction with a target biomaterial is coated on an electrode of the biosensor. .

Generally, an electrochemical biosensor is an electrochemical biosensor that uses an electrode coated with a biologically specific reactant such as an enzyme, an antigen, an antibody, a hormone, and the like, Means an apparatus that outputs an electrical signal according to a chemical reaction. That is, an electrochemical biosensor is a device that provides specific information about a bio material as a current value or a voltage value. Recently, as these biosensors have been applied to blood glucose measurement systems and various kinds of precision medical diagnosis systems, there is a growing interest and demand for techniques for improving the accuracy and reproducibility of measured values measured by a biosensor.

However, as disclosed in Korean Patent Laid-Open Nos. 10-2004-0028437 and 10-2014-0005156, a reaction material for an electrochemical reaction with a target biomaterial is fixed to an electrode of a biosensor In the conventional technology, since the liquid material is applied on the electrode in the actual manufacturing process and then dried, the reactant particles are dispersed in the reactive material application region due to the coffee ring effect generated in the drying process. The amount and density of biased particles are different for each biosensor as well as the accuracy and reproducibility of the measurement value using the biosensor are deteriorated and the reliability of the measurement value can not be guaranteed .

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and it is an object of the present invention to provide a biosensor that improves the accuracy and reproducibility of measured values using a biosensor and ensures the reliability of measured values, .

A biosensor robust against a coffee ring effect according to an embodiment of the present invention includes: a substrate; At least one working electrode and at least one reference electrode patterned on a surface of the substrate, respectively, with a conductive material; Wherein the working electrode and the reference electrode are coated with a predetermined area on one surface of the substrate on which the working electrode and the reference electrode are patterned and a part of the working electrode is stacked on a part of the working electrode, A layer of reactive material deposited on a portion; And a film layer stacked on one surface of the substrate on which the working electrode and the reference electrode are patterned and having a slot having a predetermined width so as to expose the reactive material layer, A terminal portion located in an outer region of the slot; A plurality of spaced-apart reaction slots spaced apart from the sidewalls of the slots, each slot having a predetermined width and extending in a widthwise direction of the slots, part; And a connection part having a narrower width than the reaction part and extending from the reaction part and connected to the terminal part.

In one embodiment, the biosensor is configured such that when the width of the slot is Ws and the distance between the longitudinal end of the reaction part facing the sidewall of the slot and the sidewall is d, .

[Equation 1]

0.075Ws? D? 0.2Ws

In one embodiment, the biosensor may be configured to satisfy the following equation (2) when the width of the reaction part is Wr and the width of the connection part is Wc.

&Quot; (2) "

0.2 Wr? Wc? 0.5 Wr

In one embodiment, the working electrode and the reference electrode each further include an extension having the same width as the connection portion and extending from the reaction portion and having an end located in an outer region of the slot, May be configured to extend in the width direction of the slot in the reaction part, respectively, and extend in opposite directions to each other in the reaction part.

In one embodiment, the biosensor may be configured to satisfy Equation (3) below when the width of the slot is Ws and the length of the extension is Le.

&Quot; (3) "

0.2Ws <Le? 0.4Ws

In one embodiment, the width of the slot may be configured to correspond to a range of 1.5 mm to 3 mm.

According to the present invention, a reaction part of an electrode to which a reactive material is applied is located in an area of a slot of a biosensor into which a target biomaterial is introduced, a reaction part which is spaced apart from the sidewalls of the slot, It is possible to improve the accuracy and reproducibility of the measurement value using the biosensor in spite of the coffee ring effect that the reactant particles are unevenly distributed along the edge of the reactive substance applied to the electrode, Reliability can be assured.

In addition, an extension part extending in the width direction of the slot in the reaction part of the electrode and connected to the terminal part of the electrode is provided in the reaction part of the electrode so as to extend in the direction opposite to the connection part, , The area of the electrode located in the slot area can be kept constant even when tolerance is generated in the width direction of the slot in the process of laminating the film layer having the slot on the substrate. As a result, And reproducibility can be further improved.

Further, regarding the structural correlation between the slot and the electrode of the biosensor and the structural correlation between the electrode reaction part, the connection part and the extension part, the reproducibility of the measurement value using the biosensor can be maintained at a high level without applying new materials or materials By providing an optimized numerical range, it is possible to facilitate the design of the biosensor and reduce the time and cost required for manufacturing the biosensor.

It will be apparent to those skilled in the art that various embodiments of the present invention can be accomplished without departing from the spirit and scope of the present invention.

1 is a perspective view illustrating a biosensor robust to a coffee ring effect according to an embodiment of the present invention.
2 is an exploded perspective view showing the biosensor of FIG.
3 is a view illustrating an electrode structure of a biosensor according to an embodiment of the present invention.
4 is a view showing a reactive material layer applied to electrodes of a general structure.
5 is a view illustrating a layer of a reactive material applied to an electrode of a biosensor according to an embodiment of the present invention.
6 is a view showing an example in which a film layer is laminated on a substrate on which electrodes having no extension portion are patterned.
7 is a view showing another example in which a film layer is laminated on a substrate on which an electrode not including an extension portion is patterned.
8 is a view showing an example in which a film layer is laminated on a substrate on which an electrode including an extended portion is patterned.
9 is a view showing another example in which a film layer is laminated on a substrate on which an electrode including an extension portion is patterned.
10 is a graph showing the coefficient of variation of the biosensor according to the interval between the reaction part of the slot side wall and the electrode.
11 is a graph showing the coefficient of variation of the biosensor according to the connection width of the electrode.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings in order to clarify solutions for technical problems of the present invention. In the following description of the present invention, however, the description of related arts will be omitted if the gist of the present invention becomes obscure. In addition, terms used in this specification are defined in consideration of the functions of the present invention, and they may vary depending on the intention or custom of a designer, a manufacturer, and the like. Therefore, the definitions of the following terms should be based on the contents throughout this specification.

FIG. 1 is a perspective view of a biosensor 100 resistant to a coffee-ring effect according to an embodiment of the present invention.

1, a biosensor 100 according to an exemplary embodiment of the present invention includes a substrate 110, electrodes 120 and 130, a reactive material layer 140 and a film layer 150, , An outer film layer 160 according to an embodiment, and the like. The biosensor 100 may have a stacked structure in which electrodes 120 and 130, a reactive material layer 140, a film layer 150, and an outer film layer 160 are stacked on one surface of a substrate 110 .

A slot 152 into which the target bio material to be analyzed is inputted is provided in the film layer 150 stacked on the substrate 110. The outer film layer 160 laminated on the film layer 150 may be provided with a discharge port 162 for discharging the air inside the slot 152 as the target biomaterial enters the slot 152. A reactive material layer 140 including a substance that causes an electrochemical reaction with a target biomaterial is applied and laminated to a portion of the substrate corresponding to the inner area of the slot 152 of the entire substrate 110. [

In the present specification, 'biomaterial' is meant to include all biomaterials capable of quantitatively measuring the characteristics of amorphometry applied to electrochemical techniques. For example, the target biomaterial may be a biological material such as blood, saliva, a cell, a gene, or the like, a biochemical material, or a biomaterial or a material derived from a biochemical material.

2 is an exploded perspective view of the biosensor 100 of FIG.

As shown in FIG. 2, the substrate 110 corresponds to a base layer of the biosensor 100, and may be formed of an insulating material. At least one working electrode 120 and at least one reference electrode 130 are patterned on a surface of the substrate 110 with a conductive material. For example, the working electrode 120 and the reference electrode 130 may be formed on one side of the substrate 110 through a screen printing process using carbon ink.

The reactive material layer 140 includes a material that causes an electrochemical reaction with the target biomaterial and is applied on one surface of the substrate 110 on which the working electrode 120 and the reference electrode 130 are patterned, A portion is deposited on a portion of the working electrode 120 and another portion is deposited on a portion of the reference electrode 130.

The film layer 150 is stacked on one surface of the substrate 110 on which the working electrode 120 and the reference electrode 130 are patterned and has a predetermined width to expose the reactive material layer 140, Respectively. In this case, the slot 152 is constituted by a U-shaped groove recessed in the horizontal direction of the film layer 150 and having a certain opening at the edge of the film layer 150 and a certain width toward the center of the film layer 150 . The order of lamination between the reactive material layer 140 and the film layer 150 may be appropriately changed according to the embodiment.

The outer film layer 160 is configured to laminate to the film layer 150 to protect the inner space of the slot 152 in which the reactive material layer 140 is located. The discharge port 162 formed in the outer film layer 160 is formed in the slot 152 so that the internal air of the slot 152 is discharged to the outside as the target bio material is introduced into the internal space of the slot 152 by capillary phenomenon, As shown in FIG. The outer film layer 160 may be made of a hydrophilic material. When the outer film layer 160 is made of a hydrophilic material, the introduction of the target biomaterial containing water can be facilitated.

The measurement system for measuring the characteristics of the target biomaterial using the biosensor 100 described above can quantitatively measure the characteristics of the target biomaterial by applying amperometry among the electrochemical techniques. That is, the measurement system applies a voltage of a certain magnitude to the working electrode 120 of the biosensor 100 and controls the biosensor 100 in proportion to the concentration or content of the target biosensor input to the biosensor 100 By measuring the magnitude of the oxidation-reduction current that is generated, a quantified measurement of the target biomaterial can be provided.

For example, when the biosensor 100 is constituted by a glucose sensor used in a blood glucose measurement system, the reactive material layer 140 may include an enzyme such as a glucose oxidase (GOx) or a glucose dehydrogenase (GDH) And an electron transfer mediator which is reduced by receiving an electron upon an enzyme reaction, and the like. In this case, an enzyme such as GOx or GDH, which reacts with the sugar to supply electrons to the medium, is contained at a concentration of 1000 to 5000 U / ml, and serves as an electron transfer mediator between the enzyme and the working electrode 120 Of ferricyanide, ruthenium, or osmium based on 100 to 500 mM of the compound. In addition, Triton X-100 or Tween-100, which contains BSA (Bovine serum albumin) in an amount of 0.1 to 10 wt% and maintains the activity of the enzyme, And 0.1 to 2 wt% of a fixing agent such as polyethyleneglycol (PEG), polyvinylpyrrolidone (PVP), or agarose to aid in fixing the reaction material may be contained in an amount of 0.1 to 1 wt% have.

The blood glucose measurement system using the biosensor 100 does not directly measure the electrons generated due to the reaction of the glucose and the enzyme in the biosensor 100, The blood glucose level is measured by measuring the magnitude of the generated oxidation-reduction current, that is, the magnitude of the current output through the working electrode 120 of the biosensor 100.

On the other hand, the current value i (t) of the biosensor applying amperometry over time can be calculated through the Cottrell's equation as follows.

[Cotrel type]

i (t) = (nFAD ^1/2 C ₀ ) / (tt) ^1/2

In the Coctrel equation, n is the number of electrons involved in the electrochemical reaction, F is the Faraday constant, A is the electrode area, D is the diffusion coefficient, C ₀ is the initial concentration of the material (reduced medium) .

As shown in the Coctrel equation, the current value of the biosensor is determined by taking the number (n) of electrons participating in the reaction and the area (A) of the electrode as factors, respectively. Accordingly, in order to improve the accuracy and reproducibility of the measurement value using the biosensor, it is necessary to prevent the edge portion of the reaction material layer 140, which is unpredictably biased due to the coffee ring effect, from participating in the electrochemical reaction On the other hand, it is necessary to keep the area of the electrode used in the electrochemical reaction constant.

The working electrode 120 and the reference electrode 130 of the biosensor 100 according to an embodiment of the present invention may include the terminal portions 122 and 132, the reaction portions 124 and 134, 136, and may further include extensions 128, 138, depending on the embodiment.

The terminal portions 122 and 132 are located in an outer region of the slot 152 formed in the film layer 150 stacked on the substrate 110 and are configured to be electrically connected to an external circuit. The shapes of the terminal portions 122 and 132 can be variously modified.

The reaction parts 124 and 134 are positioned in the inner region of the slot 152 and have a constant width and extend by a predetermined length in the width direction of the slot 152, And spaced apart from the sidewalls of the slots 152 that face each other.

The connection portions 126 and 136 are configured to be narrower than the reaction portions 124 and 134 and extend from the reaction portions 124 and 134 to be connected to the terminal portions 122 and 132. In this case, one end of each of the connection portions 126 and 136 is located in the inner region of the slot 152, and the other end of the connection portions 126 and 136 is located in the outer region of the slot 152.

When the working electrode 120 and the reference electrode 130 further include the extension portions 128 and 138, the extension portions 128 and 138 have the same width as the connection portions 126 and 136, , 134 so that the distal end is located in the outer region of the slot 152. In this case, the connection portions 126 and 136 and the extension portions 128 and 138 are configured to extend in the width direction of the slots 152 in the reaction portions 124 and 134, respectively, and extend in opposite directions to each other.

3 shows an electrode structure of the biosensor 100 according to an embodiment of the present invention.

3, the reaction units 124 and 134 of each of the electrodes 120 and 130 are located in the inner region of the slot 152 and have a constant width and have a predetermined length in the width direction of the slot 152 And spaced from each other by a predetermined distance d1, d2 from the side wall of the slot 152, which is opposite in the width direction of the slot 152, at both ends in the longitudinal direction.

In this case, the spaces d1 and d2 between the reaction parts 124 and 134 and the side walls of the slots 152 are set such that the edge portions of the reactive material layer 140, The area of the reaction parts 124 and 134 should not be too small, while not directly contacting the reaction parts 124 and 134. For this, the distance between the longitudinal ends of the reaction parts 124 and 134, which face the side wall of the slot 152, and the corresponding side wall can be determined within a range satisfying the following equation (1).

[Equation 1]

0.075Ws? D? 0.2Ws [mm]

In Equation 1, Ws is the width of the slot 152, and d is the distance between the longitudinal end of the reacting portions 124 and 134 and the corresponding sidewall facing the sidewall of the slot 152. In this case, the width Ws of the slot 152 may have a size corresponding to a range of 1.5 mm or more and 3 mm or less.

In Fig. 3, d1 and d2 have a size corresponding to a range of 0.075 Ws to 0.2 Ws, respectively. When d1 and d2 are smaller than 0.075 Ws, the edge portions of the reactant material layer 140, which are ununiformly biased due to the coffee ring effect, contact the reactive portions 124 and 134, Participate in the oxidation-reduction reaction, and the reproducibility of the measurement value using the biosensor 100 is lowered. When d1 and d2 are larger than 0.2 Ws, the area of the reaction parts 124 and 134 becomes excessively small, so that the output current of the biosensor 100 decreases. As a result, the measured values of the biosensor 100 Rather it will degrade accuracy.

The connection portions 126 and 136 of the electrodes 120 and 130 are extended from the reaction portions 124 and 134 to the terminal portions 122 and 132 with a narrower width than the reaction portions 124 and 134, As shown in FIG.

In this case, the width Wc of the connection portions 126 and 136 should be determined within a range that minimizes the contact area with the edge portion of the reactive material layer 140, and is easy to implement and does not cause disconnection. For this purpose, the width Wc of the connecting portions 126 and 136 can be determined within a range satisfying the following equation (2).

&Quot; (2) &quot;

0.2 Wr? Wc? 0.5 Wr [mm]

In Equation (2), Wr is the width of the reacting portions 124 and 134, and Wc is the width of the connecting portions 126 and 136. In this case, the width of the reaction part 124 of the working electrode 120 may range from 0.2 mm to 3 mm, and the width of the reaction part 134 of the reference electrode 130 may be 0.2 mm or more and 4.5 mm. &lt; / RTI &gt;

3, the width Wc of the connecting portion 126 has a size corresponding to a range of 0.2 Wr or more and 0.5 Wr or less. When the width Wc of the connecting portion 126 is smaller than 0.2 Wr, actual implementation is difficult, resulting in manufacturing defects or disconnection. When the width Wc of the connection portion 126 is larger than 0.5 Wr, the contact area between the edge portion of the reactive material layer 140 and the connection portion 126 increases, and the measured value of the biosensor 100 The reproducibility is degraded.

On the other hand, in the case where the working electrode 120 and the reference electrode 130 further include extensions 128 and 138 extending in the direction opposite to the connecting portions 126 and 136 in the reaction portions 124 and 134, The portions 128 and 138 may be configured to have the same width as the connecting portions 126 and 136.

Figure 4 shows a layer of reactive material 16 applied to electrodes 12, 14 of general construction.

As shown in FIG. 4, when the reactant solution coated on the electrodes 12 and 14 having the general structure formed on the substrate 10 is dried to form the reactive material layer 16, Due to the effect of the coffee ring effect, the reactant particles are unevenly distributed along the edge of the reactive material layer 16, and the amount and density of the biased particles are also different for each biosensor. Since the electrodes 12 and 14 of the general structure have a large area of the portions x1 to x4 contacting the edge portions of the reactive material layer 16, And thus the accuracy and reproducibility of the measurement value using the biosensor are deteriorated and the reliability of the measurement value can not be guaranteed.

FIG. 5 is a view illustrating a reactive material layer 140 applied to electrodes 120 and 130 of a biosensor according to an embodiment of the present invention.

5, in the present invention, even though the reactant particles applied to the substrate 110 are unevenly biased along the edges of the reactive material layer 140 due to the coffee ring effect, Since the areas of the connecting portions 126 and 136 and the portions y1 to y4 of the extension portions 128 and 138 that contact the edge portions of the electrodes 120 and 130 are small, The center portion of the reactive material layer 140 that is in contact with the reaction portions 124 and 134 of the reactive material layer 140 is involved and the edge portions of the reactive material layer 140 participate at a very low rate that does not affect the measured value. Therefore, according to the present invention, it is possible to improve the accuracy and reproducibility of the measurement value using the biosensor and ensure the reliability of the measurement value.

3, the working electrode 120 and the reference electrode 130 patterned on the substrate 110 of the biosensor according to the embodiment of the present invention have the same width as the connecting portions 126 and 136, respectively And may further include extension portions 128 and 138 extending from the reaction portions 124 and 134 and configured to be positioned at the outer region of the slot 152. In this case, the connecting portions 126 and 136 and the extending portions 128 and 138 may be configured to extend in the width direction of the slots 152 in the reaction portions 124 and 134, respectively, and extend in opposite directions to each other.

The reason why the electrodes 120 and 130 of the biosensor 100 are provided with the extensions 128 and 138 is that when the film layer 150 having the slots 152 is laminated on the substrate 110, In order to further improve the accuracy and reproducibility of the measurement value using the biosensor by keeping the area of the electrode located in the inner region of the slot 152 constant even when a tolerance is generated in the direction of the width Ws of the biosensor 152 to be.

To this end, the length Le of the extensions 128 and 138 may be determined to satisfy the following equation (3).

&Quot; (3) &quot;

0.2Ws <Le? 0.4Ws [mm]

In Equation (3), Ws is the width of the slot 152 and Le is the length of the extensions 128 and 138.

Even when a tolerance is generated in the direction of the width Ws of the slot 152 in the process of laminating the film layer 150 on the substrate 110, the area of the electrode located in the inner region of the slot 152 is kept constant The extensions 128 and 138 must have a margin of a certain length l ₀ in the outer region of the slot 152. Therefore, the length Le of the extension portions 128, 138 should be at least longer than 0.2 Ws, which is the maximum value of d1 or d2. Since the tolerances in the lamination of the film layers 150 are allowed only when the reaction portions 124 and 134 of the electrodes 120 and 130 are located in the inner region of the slot 152, The length Le does not need to be longer than 0.4 Ws which is the maximum value of d1 + d2.

3, the connecting portion 126 of the working electrode 120 should be formed to be longer than the extending portion 138 of the reference electrode 130 without being shorter than the extending portion 128 thereof. Also, the connection portion 136 of the reference electrode 130 should be formed not to be shorter than the extension portion 138 thereof.

FIG. 6 shows an example in which a film layer 150a is laminated on a substrate 110a on which an electrode 120a not including an extended portion is patterned.

7 shows another example in which the film layer 150a is laminated on the substrate 110a on which the electrode 120a not including the extension part is patterned.

6, when the film layer 150a is laminated on the substrate 110a on which the electrode 120a composed of only the terminal portion 122a, the reaction portion 124a and the connection portion 126a is patterned, When the tolerance occurs, the area Sa of the connection portion 126a located in the slot region of the film layer 150 is narrowed, so that the electrode area used in the electrochemical reaction is reduced.

7, in the process of stacking the film layer 150a on the substrate 110a on which the electrode 120a composed of only the terminal portion 122a, the reaction portion 124a and the connection portion 126a is patterned, When a tolerance occurs to the right, the area Sa 'of the connection portion 126a located in the slot region of the film layer 150 is widened, and the electrode area used for the electrochemical reaction increases.

When the electrode of the biosensor does not include the extension portion, the electrode area used for the electrochemical reaction differs from one biosensor to another because of the tolerance generated in manufacturing the biosensor.

8 shows an example in which a film layer 150 is laminated on a substrate 110 on which an electrode 120 including an extension part 128 is patterned.

9 shows another example in which the film layer 150 is laminated on the substrate 110 on which the electrodes 120 including the extending portions 128 are patterned.

The film layer 150 is formed on the substrate 110 on which the electrode 120 including the terminal portion 122, the reaction portion 124, the connection portion 126, and the extension portion 128 is patterned, The area S2 of the connection part 126 located in the slot internal area of the film layer 150 is narrowed but the area S2 of the film layer 150 is located inside the slot of the film layer 150 The area S1 of the extension portion 128 becomes wider. Since the connection portion 126 and the extension portion 128 have the same width, the electrode area used in the electrochemical reaction is kept constant despite the tolerances.

9, an electrode 120 including a terminal portion 122, a reaction portion 124, a connection portion 126, and an extension portion 128 is formed on a substrate 110 patterned with a film layer The area S2 'of the connection part 126 located in the slot internal area of the film layer 150 is widened in the process of stacking the film layers 150. However, The area S1 'of the extension portion 128 located at the end portion becomes narrow. Since the connection portion 126 and the extension portion 128 have the same width, the electrode area used in the electrochemical reaction is kept constant despite the tolerances.

In this way, when the electrode of the biosensor includes the above-described extension, the electrode area used for the electrochemical reaction is kept constant in all the biosensors, regardless of the tolerance generated in manufacturing the biosensor, It is possible to ensure the reproducibility of the measured values using a high level.

Hereinafter, the reproducibility improvement effect of the biosensor according to one embodiment of the present invention will be verified with reference to the experimental results of the measurement of the coefficient of variation.

The coefficient of variation indicates the standard deviation of the population consisting of blood glucose values measured by the biosensor as a percentage of the average value of the population, and the smaller the size, the higher the reproducibility.

In the experiment of measuring the coefficient of variation, a biosensor having a structure as shown in FIG. 2 as a whole and using a biosensor constructed as a blood glucose sensor was used. Hypoglycemia blood having a blood glucose level of 119 mg / dL and high blood glucose blood glucose having a blood glucose level of 299 mg / dL were used as a target biomaterial.

FIG. 10 is a graph showing the variation coefficient of the biosensor according to the interval between the side wall of the slot and the reaction part of the electrode. In the experiment related to Fig. 10, while maintaining the width Ws of the slot for each biosensor constantly and changing the length of the reaction part of the electrode, the hypoglycemia blood having a blood sugar level of 119 mg / dL was administered 30 times with a blood glucose level of 299 mg / Blood was measured 20 times for blood.

As shown in FIG. 10, when the intervals d1 and d2 between the sidewalls of the slots and the reacting portions of the electrodes become larger than the width Ws of the slot by 0.05 Ws or more, It can be seen that the coefficient of variation has a value within 4% and shows a high level of reproducibility. Particularly, when the intervals d1 and d2 fall within the range of 0.075 Ws to 0.2 Ws with respect to the width Ws of the slots 152, the coefficient of variation has a value within 3% and a relatively higher level of reproducibility . &Lt; / RTI &gt; However, if the intervals d1 and d2 are larger than 0.2 Ws, the area of the reaction area of the electrode is excessively reduced, and the reproducibility is rather lowered.

11 is a graph showing the coefficient of variation of the biosensor according to the connection width of the electrode. In the experiment related to Fig. 11, 30 times for hypoglycemic blood having a blood glucose level of 119 mg / dL, while maintaining the reaction width Wr of the electrode constant for each biosensor and changing the width Wc of the connecting portion and the extension portion of the electrode, The blood glucose level was measured 20 times for hyperglycemic blood having a blood sugar level of 299 mg / dL.

As shown in FIG. 11, if the width Wc of the connecting portion and the extending portion is reduced to 0.5 Wr or less with respect to the width Wr of the reaction portion, the coefficient of variation of measured values is within 4% for hyperglycemic blood as well as hypoglycemic blood Value and high level of reproducibility. However, if the width (Wc) of the connecting portion and the extending portion is less than 0.2 Wr, it is difficult to realize the actual implementation, resulting in manufacturing failure and disconnection.

As described above, according to the present invention, a reaction part of an electrode to which a reactive material is applied is located in a region of a slot of a biosensor into which a target biomolecule flows, and the reaction part of the electrode is spaced apart from the sidewalls of the slot, So that the accuracy and reproducibility of the measured value using the biosensor can be improved in spite of the coffee ring effect in which the reactant particles are unevenly biased along the edge of the reactive substance applied to the electrode And the reliability of the measured value can be guaranteed.

In addition, an extension part extending in the width direction of the slot in the reaction part of the electrode and connected to the terminal part of the electrode is provided in the reaction part of the electrode so as to extend in the direction opposite to the connection part, , The area of the electrode located in the slot area can be kept constant even when tolerance is generated in the width direction of the slot in the process of laminating the film layer having the slot on the substrate. As a result, And reproducibility can be further improved.

Further, regarding the structural correlation between the slot and the electrode of the biosensor and the structural correlation between the electrode reaction part, the connection part and the extension part, the reproducibility of the measurement value using the biosensor can be maintained at a high level without applying new materials or materials By providing an optimized numerical range, it is possible to facilitate the design of the biosensor and reduce the time and cost required for manufacturing the biosensor.

Furthermore, it should be understood that the embodiments according to the present invention can solve various technical problems other than those mentioned in the specification in the related technical field as well as the related art.

The present invention has been described with reference to specific embodiments. It will be apparent, however, to one skilled in the art that various modifications may be practiced within the technical scope of the invention. Therefore, the above-described embodiments should be considered from an illustrative point of view, not from a restrictive viewpoint. That is, the scope of the true technical idea of the present invention is shown in the claims, and all differences within the scope of equivalents thereof should be construed as being included in the present invention.

100: biosensor 110: substrate
120: working electrode 130: reference electrode
140: Reactive material layer 150: Film layer
152: Slot 160: outer film layer

Claims (6)

Board; At least one working electrode and at least one reference electrode patterned on a surface of the substrate, respectively, with a conductive material; Wherein the working electrode and the reference electrode are coated with a predetermined area on one surface of the substrate on which the working electrode and the reference electrode are patterned and a part of the working electrode is stacked on a part of the working electrode, A layer of reactive material deposited on a portion; And a film layer laminated on one surface of the substrate on which the working electrode and the reference electrode are patterned and having a slot having a predetermined width so as to expose the reactive material layer,
Wherein the working electrode and the reference electrode each comprise:
A terminal portion located in an outer region of the slot;
A plurality of spaced-apart reaction slots spaced apart from the sidewalls of the slots, each slot having a predetermined width and extending in a widthwise direction of the slots, part; And
And a connection portion extending from the reaction portion and connected to the terminal portion, the connection portion being narrower in width than the reaction portion. The method of claim 1, wherein
When the width of the slot is Ws and the distance between the longitudinal end of the reaction part facing the side wall of the slot and the sidewall is d, the following equation (1) is satisfied: .
[Equation 1]
0.075Ws? D? 0.2Ws The method according to claim 1,
Wherein a width of the reaction part is Wr and a width of the connection part is Wc, the following formula (2) is satisfied.
&Quot; (2) &quot;
0.2 Wr? Wc? 0.5 Wr The method according to claim 1,
Wherein the working electrode and the reference electrode each include an extension portion having the same width as the connection portion and extending in the reaction portion and having an end located in an outer region of the slot,
Wherein the connection portion and the extension portion extend in the width direction of the slot in the reaction portion and extend in opposite directions to each other in the reaction portion. 5. The method of claim 4,
Wherein when the width of the slot is Ws and the length of the extended portion is Le, the following expression (3) is satisfied.
&Quot; (3) &quot;
0.2Ws <Le? 0.4Ws The method according to claim 1,
Wherein the width of the slot corresponds to a range of 1.5 mm or more and 3 mm or less.

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