KR20160012767A - Method for manufacturing carbon electrode material for nonenzymatic glucose biosensor and carbon electrode material manufactured by the method, method for manufacturing working electrode for nonenzymatic glucose biosensor - Google Patents

Abstract

Disclosed are a method for manufacturing a carbon electrode material for a nonenzymatic glucose biosensor, a carbon electrode material manufactured by the same, and a method for manufacturing a working electrode for a nonenzymatic glucose biosensor. The method for manufacturing a carbon electrode material for a nonenzymatic glucose biosensor comprises: (a) a step of depositing gold (Au) on a carbon material to manufacture a carbon electrode material, and dissolving a metal oxide precursor in a solvent to manufacture a metal oxide precursor solution; (b) a step of mixing the carbon electrode material and the metal oxide precursor solution to manufacture a mixed solution; and (c) a step of heat-treating the mixed solution to manufacture a metal oxide-carbon electrode material compound. According to the present invention, gold (Au) is deposited on the carbon material, and metal oxide is introduced to provide excellent sensitivity to glucose.

Description

FIELD OF THE INVENTION [0001] The present invention relates to a method for producing a carbon electrode material for a non-enzyme glucose biosensor, and a method for manufacturing a carbon electrode material and an operating electrode for a non-enzyme glucose biosensor, , METHOD FOR MANUFACTURING WORKING ELECTRODE FOR NONENZYMATIC GLUCOSE BIOSENSOR}

The present invention relates to a method for producing a carbon electrode material for a non-enzyme glucose biosensor, and a method for manufacturing the carbon electrode material and the working electrode for the non-enzyme glucose biosensor, And a method of manufacturing a carbon electrode material for a non-enzyme glucose biosensor and a method for manufacturing an electrode for a non-enzyme glucose biosensor, .

Generally, a biosensor immobilizes a substance capable of reacting with a specific substance on an electrode surface, converts it into an electrical signal, and analyzes its component or amount.

More than 90% of domestic biosensors are medical biosensors, and most of them are easy to measure blood glucose. Recently, there have been many attempts to apply carbon nanotubes in biotechnology field. Detection of glucose sensor, protein, detection of specific DNA sequence Research on carbon nanotube-based biosensors has attracted attention.

These biosensors are divided into two categories: an enzyme glucose biosensor using a glucose enzyme and a non-enzyme glucose biosensor not using a glucose enzyme when detecting glucose. Enzyme Glucose biosensors use enzymes, so they are highly selective and therefore highly sensitive. However, since the enzyme is a protein, it is not only vulnerable to the external environment such as temperature, pH, and humidity, but also has a high price, which has limited the development of a glucose biosensor. In addition, the hydrogen peroxide produced by the enzymatic reaction causes denaturation of the enzyme causing a great problem in reproducibility, accompanied by an increase in the cost due to the enzyme immobilization process and high material cost.

On the other hand, since non-enzymatic glucose does not use an enzyme, it is strong against the external environment and can reduce the cost of purchasing the enzyme, making it possible to manufacture a glucose biosensor which is easy to commercialize. However, the non-enzyme glucose biosensor has a problem in that the sensitivity is lower than that of the enzyme glucose biosensor.

In order to overcome these limitations, metals such as glucose, a metal oxide, and an alloy which are easily oxidized and reduced are used. In particular, metal oxides are widely used as electrode materials for non-enzyme glucose biosensors because they are easy to manufacture and have a low cost.

However, when a glucose biosensor electrode material is made of such a metal oxide, there is a disadvantage that it exhibits high sensitivity only to specific forms such as nano-wire, nano-rod, and nano-flower , Complex processes are required to produce these specific types of metal oxides. Specifically, nano-rods require two or more kinds of metal oxide precursors, and it is known that the nano-rods can be manufactured only after a heat treatment process of 6 steps or more. Also, in the case of nanoflowers, there is a risk of environmental pollution by using acetone, formamide, and it is known that it takes period of more than 15 days to periodically remove the formed layer.

Disclosure of Invention Technical Problem [8] Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and it is an object of the present invention to provide a carbon electrode material for non-enzymatic glucose biosensor capable of realizing excellent glucose sensing sensitivity by depositing gold (Au) And a method for producing a carbon electrode material and a working electrode for a non-enzyme glucose biosensor produced by the method.

The objects of the present invention are not limited to those mentioned above, and other objects not mentioned can be clearly understood by those skilled in the art from the following description.

According to an aspect of the present invention, there is provided a method of manufacturing a metal oxide precursor solution, comprising the steps of: (a) depositing gold (Au) on a carbonaceous material to prepare a carbon electrode material and dissolving a metal oxide precursor in the solvent; (b) mixing the carbon electrode material and the metal oxide precursor solution to prepare a mixed solution; And (c) heat-treating the mixed solution to prepare a metal oxide-carbon electrode composite material. The present invention also provides a method of manufacturing a carbon electrode material for a non-enzymatic glucose biosensor.

The metal oxide _{precursor, Cu (NO 3) 2 ·} 3H 2 O, Cu (CH 3 COO) 2 · H 2 O, CuCl 2 · 2H 2 O, NiSO 4 (H 2 O) 6, NiCl 2 · 6H 2 O, Ni (CH ₃ CO ₂ ) ₂ , Ti {OCH (CH ₃ ) ₂ } ₄ .

In the mixing process of the step (b), the carbon electrode material may be mixed in an amount of 2 to 10 parts by weight based on 100 parts by weight of the metal oxide precursor.

The heat treatment may be performed at 150 to 200 DEG C for 1 to 2 hours.

After the step (c), the metal oxide-carbon electrode composite material is washed with water and dried, and the drying may be performed at 80 to 120 ° C for 24 to 30 hours.

According to another aspect of the present invention, there is provided a method for manufacturing a carbon electrode material, comprising the steps of: (a) preparing a metal oxide-carbon electrode composite material prepared by the method for producing a carbon electrode material for a non-enzyme glucose biosensor; And (b) mixing the metal oxide-carbon electrode composite material with a binder and a volatile solvent, followed by filtration under reduced pressure to produce a working electrode.

After the step (b), drying the working electrode may further include drying the working electrode.

The drying may be performed at 20 to 120 ° C for 24 to 30 hours.

According to the present invention, it is possible to realize excellent glucose sensing sensitivity by depositing gold (Au) on a carbon material and introducing a metal oxide.

In addition, by introducing a metal oxide after gold (Au) deposition, the metal oxide can be introduced into a nano-cluster shape increasing the sensitivity of the non-enzyme glucose biosensor.

In addition, a metal oxide-carbon electrode composite material for a non-enzyme glucose biosensor that can be used without a separate substrate can be produced.

The effects of the present invention are not limited to those mentioned above, and other effects not mentioned can be clearly understood by those skilled in the art from the following description.

1 is a flowchart showing a method of manufacturing a carbon electrode material for a non-enzyme glucose biosensor according to an embodiment of the present invention.
FIG. 2 is a flowchart showing a method of manufacturing a working electrode for a non-enzymatic glucose biosensor according to an embodiment of the present invention.
FIG. 3A is a UHR-SEM image of a general carbon nanotube, and FIG. 3B is a UHR-SEM image of a carbon electrode material on which gold (Au) is deposited as an intermediate product of Example 1 of the present invention.
4 is an FE-SEM image of the metal oxide-carbon electrode material composite produced by Example 1 of the present invention and the metal oxide-carbon electrode material composite produced by Comparative Example 2;
5 is a graph comparing XRD spectra of the metal oxide-carbon electrode composite material prepared in Example 1 of the present invention and the carbon electrode material prepared in Comparative Examples 1 to 3.
6 is a graph showing current response characteristics of Example 2, Comparative Example 4, Comparative Example 5, and Comparative Example 6 of the present invention.
7 is a graph showing a result of measurement of a current change in the second embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. It will be apparent to those skilled in the art that the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, It is provided to let you know. Wherein like reference numerals refer to like elements throughout.

The method of manufacturing a carbon electrode material for a non-enzymatic glucose biosensor according to an embodiment of the present invention (hereinafter referred to as a "manufacturing method") is a method of manufacturing a carbon electrode material for a non-enzymatic glucose biosensor by a simple manufacturing process different from a nanorod, a nanowire, And to produce a carbon electrode material capable of sensitizing glucose sensing.

Hereinafter, the present invention will be described in detail.

As shown in FIG. 1, a manufacturing method according to an exemplary embodiment of the present invention includes the steps of depositing gold (Au) on a carbon material to produce a carbon electrode material and dissolving a metal oxide precursor in a solvent to prepare a metal oxide precursor solution A step S120 of mixing a carbon electrode material and a metal oxide precursor solution to prepare a mixed solution S110, a step S120 of preparing a metal oxide-carbon electrode material composite by heat treating the mixed solution S120, - washing and drying the carbon electrode composite material (S130).

First, in step S100, gold (Au) is deposited on the carbon material to prepare a carbon electrode material, and a metal oxide precursor solution is dissolved in the solvent to prepare a metal oxide precursor solution. The metal oxide precursor solution is provided for the introduction of the metal oxide to the carbon electrode material.

In one example of the present invention, the carbon material may be selected from carbon fiber, activated carbon, activated carbon fiber, carbon nanotube, graphene, and carbon black. Also, gold (Au) is provided to allow easy and efficient introduction of metal oxide into the carbon material. The Au may be deposited on the surface of the carbonaceous material through various deposition methods such as evaporation, sputtering, ion plating and the like.

On the other hand, when a metal oxide is introduced into the carbon material, an energy of about -156 kJ / mol or more is required. In the present invention, gold (Au) reduces the energy required to allow metal oxide to be introduced into the carbon material can do. In addition, as described later, nano-cluster-like metal oxide can be introduced into the carbon material deposited with gold (Au), thereby ultimately improving glucose sensing sensitivity.

Referring back to step S100, it is preferable that the gold (Au) deposition time is approximately 25 seconds to 35 seconds, and the purity of gold (Au) is preferably 99.99% or more.

When the gold (Au) deposition time is less than 25 seconds, a small amount of gold (Au) is introduced into the carbonaceous material, so that the metal oxide is introduced into the carbonaceous material in the form of nano-clusters and eventually glucose sensing sensitivity There is a risk of degradation.

In addition, when the gold (Au) deposition time exceeds 35 seconds, gold (Au) can not be uniformly deposited on the carbon material, and deposition is carried out in a specific region so that sensitivity to glucose sensing of the metal oxide- It is not desirable because there is a possibility of becoming.

The gold (Au) is preferably deposited in an amount of 0.1 to 1 part by weight based on 100 parts by weight of the carbon material. When the amount of gold (Au) is less than the lower limit, a small amount of gold (Au) It is not preferable because the metal may be introduced into the carbon material without being in the form of a nano-cluster, which may eventually degrade the sensitivity of glucose sensing. When the amount of gold (Au) exceeds the upper limit value, Au is not uniformly deposited and is deposited in a specific region in a state of being deposited, the contact resistance is increased and the sensitivity of glucose sensing of the metal oxide-carbon electrode composite material is lowered, which is not preferable

In step S100, a metal oxide precursor solution is prepared by dissolving a metal oxide precursor in a solvent to introduce metal oxide into the carbon material deposited with gold (Au).

In the present invention, as the metal oxide precursor, a metal hydroxide containing an active hydroxyl group (OH < ^- & gt ^; ) is used. See, for examples thereof, a metal hydroxide containing Cu, Ni and _{Ti Cu (NO 3) 2 ·} 3H 2 O, Cu (CH 3 COO) 2 · H 2 O, CuCl 2 · 2H 2 O, NiSO 4 ( H ₂ O) ₆ , NiCl ₂ .6H ₂ O, Ni (CH ₃ CO ₂ ) ₂ and Ti {OCH (CH ₃ ) ₂ } ₄ .

The metal oxide precursor is a material having excellent electrical conductivity, which allows a biosensor working electrode described later to realize a high glucose sensing sensitivity. That is, due to the gold (Au) deposited on the carbon material, the metal oxide is introduced into the carbonaceous material in the form of nano-cluster, thereby realizing excellent glucose sensing sensitivity of the working electrode.

In step S110, the metal oxide precursor solution prepared through step S100 and the carbon electrode material on which gold (Au) is deposited are mixed. At this time, the mixing ratio of the metal oxide precursor and the carbon electrode material on which the Au is deposited is preferably 2 to 10 parts by weight of the carbon electrode material on which Au is deposited, relative to 100 parts by weight of the metal oxide precursor. In addition, since the carbon electrode material is a material having a relatively low density, it is provided in a significantly smaller amount than the metal oxide precursor.

Here, when the mixing ratio of the carbon electrode material on which gold (Au) is deposited is less than the lower limit value, the amount of gold (Au) introduced into the carbon electrode material is limited, so that even when a large amount of metal oxide precursor is used, Is limited. That is, when the mixing ratio of the carbon electrode material is less than the lower limit value, there is no difference between the lower limit value and the amount of the metal oxide to be introduced, and only the waste of resources is wasted.

In addition, when the mixing ratio of the carbon electrode material on which gold (Au) is deposited exceeds the upper limit value, the amount of metal oxide introduced into the carbon electrode material may not be sufficient, which is not preferable.

In the present invention, the solvent may be any solvent capable of dissolving the metal oxide precursor, and examples thereof include, but not limited to, NaOH, KOH, and H ₂ O.

Subsequently, the mixed solution is heat-treated to produce a metal oxide-carbon electrode composite material (S120).

The heat treatment is performed to obtain a metal oxide-carbon electrode composite material in which a metal oxide is introduced into the carbon electrode material, and is preferably performed at 150 to 200 ° C for 1 to 2 hours.

If the heat treatment temperature and the heat treatment time are less than the lower limit, there is a fear that the introduction of the metal oxide to the surface of the carbon electrode material may not be sufficient, which may result in a significant drop in the glucose sensing sensitivity of the working electrode. Specifically, there arises a problem that the sensitivity of the working electrode is lowered by about 3 to 4 times as compared with the case of normal operation.

In addition, when the heat treatment temperature and the heat treatment time exceed the upper limit value, a problem may occur in the shape of the metal oxide introduced into the carbon electrode material due to excessive reaction. Concretely, there is a fear that a metal oxide having a relatively insensitive sensing sensitivity, which is not a nano-cluster structure capable of sensing glucose more sensitively, may be introduced. Further, there may arise a problem in the particle size and uniformity of the metal oxide, which is undesirable because the particle size may be formed in a size out of the desired size range and the size of the plurality of particles may become non-uniform. This is undesirable because it can result in a marked decrease in the glucose sensing sensitivity of the working electrode.

Next, in step S120, the produced metal oxide-carbon electrode composite material is washed with water and dried to produce a carbon electrode material for a non-enzyme glucose biosensor (S130).

The drying step after the water washing step is preferably carried out at 80 to 120 DEG C for 24 to 30 hours.

Here, when the drying temperature is lower than 80 캜, the drying time for sufficiently drying the metal oxide-carbon electrode composite material is not only unnecessarily increased but also difficult to dry sufficiently. If the metal oxide-carbon electrode composite material can not be sufficiently dried, moisture may remain in the metal oxide-carbon electrode composite material, resulting in difficulty in accurate glucose sensing, which is not preferable.

When the drying temperature exceeds 120 ° C, the metal oxide-carbon electrode composite material is over-dried and may be broken or broken.

On the other hand, if the drying time is less than 24 hours, it is difficult to dry the metal oxide-carbon electrode composite material sufficiently, and if the drying time exceeds 30 hours, undesired side reactions and possibility of transformation of the metal oxide- But also an unnecessary process time for drying is increased, which is not preferable.

Hereinafter, a method for manufacturing a working electrode for a non-enzyme glucose biosensor (hereinafter referred to as a working electrode manufacturing method) according to an embodiment of the present invention will be described.

As shown in FIG. 2, the manufacturing method of the working electrode according to an example of the present invention includes the steps of preparing the metal oxide-carbon electrode composite material produced by the method for manufacturing the carbon electrode material for a non-enzymatic glucose biosensor A step S210 of mixing an oxidized metal-carbon electrode composite material with a binder and a volatile solvent, followed by filtration under reduced pressure to produce a working electrode S210, and a step S220 of drying the working electrode S210.

First, step S200 is performed through steps S100, S110, and S120 described above, and detailed description thereof has been hereinbefore described, so that the following description is omitted.

Next, the oxidized metal-carbon electrode composite material is mixed with a binder and a volatile solvent, followed by filtration under reduced pressure to produce a working electrode (S210).

Specifically, in step S210, the metal oxide-carbon electrode composite material is first put into a volatile solvent, stirred for 10 minutes, and then the binder is added thereto, followed by further sintering for 1 hour. After the sterilization, sonication is performed for 1 hour. Then, the dispersed mixture is put into a glass filter of a vacuum filtration apparatus composed of a glass filter, a paper filter, and a decompressor, and the decompressor is operated, so that the electrode material in the mixture is filtered on the paper filter to become a working electrode having a certain thickness.

At this time, unless accompanied by the ultrasonic decomposition process, the electrode material and the binder are not dispersed uniformly in the mixture and are aggregated, and thus disadvantageous in that the surface of the working electrode obtained after the filtration under reduced pressure may be unevenly formed is not preferable. In addition, when the ultrasonic disintegration process is performed excessively, for example, when the ultrasonic disintegration process is performed for more than 2 hours, material damage may occur and the metal oxide and the carbon electrode material may be separated from each other.

Here, the mixing ratio of the metal oxide-carbon electrode composite material and the binder is preferably 30 to 60 parts by weight based on 100 parts by weight of the metal oxide-carbon electrode composite material.

The oxidized metal-carbon electrode material must be monolithic in order to act as the working electrode, and a contact portion between the materials must be present to facilitate electron transfer and current flow as the working electrode. The binder serves as a paste that provides a bonding force between the materials to maintain the thickness and shape of the metal oxide-carbon electrode reacting electrode.

The binder having such a role is preferably a material having good conductivity while imparting a bonding force. The binder is not particularly limited, but examples thereof include polyvinylidene fluoride (PVDF), polytetrafluoroethylene polytetrafluoroethylene (PTFE), Nafion, etc. may be used.

When the binder is less than 30 parts by weight based on 100 parts by weight of the oxidized metal-carbon electrode composite material, there is a fear that the working electrode formed after the filtration under reduced pressure may not form a single body. In addition, when the binder is provided in an amount exceeding 60 parts by weight based on 100 parts by weight of the metal oxide-carbon electrode composite material, the metal oxide-carbon electrode composite material is not uniformly dispersed in the solvent and is aggregated on either side, It is difficult to form a structure for application to the substrate. In addition, when an excess of binder is present in the oxidized metal-carbon electrode composite, accurate results may not be obtained in the working electrode analysis. Specifically, there is a risk that a redox reaction occurs between glucose and a working electrode, and a phenomenon occurs in which the binder interrupts the reaction between the glucose and the working electrode, thereby making it difficult to obtain accurate results.

The volatile solvent increases the binding force of the working electrode while dispersing the metal oxide-carbon electrode composite material in a solvent so as to be evenly mixed with the binder. The volatile solvent is preferably one which does not cause a mutual reaction with the metal oxide-carbon electrode composite material, and any of them may be used as long as it does not cause a mutual reaction. On the other hand, if a solvent which is not volatile is used unlike a volatile solvent, it takes a long time to dry the working electrode, but its use is not unavoidable.

In the present invention, the working electrode is manufactured through the reduced pressure filtration method. When the working electrode is manufactured using this method, the amount of carbon material in the step S100 determines the thickness of the working electrode. Here, carbon materials have different densities depending on the kind (carbon fiber, activated carbon, activated carbon fiber, carbon nanotube, graphene, carbon black, etc.). Therefore, when an electrode having a specific thickness is to be manufactured, different amounts of carbon materials should be used depending on the kind of the carbonaceous material to be applied. For example, a smaller amount of carbon material should be used when the density is small (i.e., a large volume), and a larger amount of carbon material should be used when the density is large (i.e., when the volume is small) .

In other words, by applying different amounts of carbon material according to the type of carbonaceous material (density difference) applied in step S100, it is possible to manufacture the working electrode having substantially similar thickness regardless of the type of carbonaceous material in step S210 .

Next, in step S210, the manufactured working electrode is dried (S220).

The drying process of the working electrode is preferably performed at 20 to 120 DEG C for 24 to 30 hours. For reference, the volatile solvent is a solvent having a very low boiling point. When such a volatile solvent is used, the solvent can be dried even at a low temperature of 20 ° C.

If the drying temperature is lower than 20 ° C, a volatile solvent remains in the working electrode, which is not preferable because accurate results can not be obtained at the time of glucose sensing. If the drying temperature exceeds 120 ° C, the metal oxide- So that it may be broken or broken.

In the present invention, the metal oxide-carbon electrode re-working electrode for a non-enzyme glucose biosensor can be manufactured through steps S100 to S120, S200 to S220, and the working electrode can be used as an electrode without a separate substrate Do.

In addition, in the case of the above-mentioned nano-rods, nanowires, and nanoflower-type metal oxides, a certain type of working electrode is manufactured and then coated on a substrate having excellent electrical conductivity such as ITO.

However, in the case of a carbon electrode material containing gold (Au) and a metal oxide, since the carbon electrode material itself serves as an electrode and a substrate in the present invention, a substrate such as a conventional ITO is not required.

In summary, the present invention can provide an electrode material capable of realizing excellent glucose sensitivity by the simple process described above, unlike nano-rods, nanowires, and nanoflowers that require complicated manufacturing processes.

Hereinafter, the present invention will be described in more detail with reference to Examples and Test Examples.

Example  1: gold ( Au Lt; RTI ID = 0.0 > metal-oxide- Carbon electrode material  Manufacture of Composites

0.05 g of carbon nanotubes (CM-350, Hanwha Chemical) was prepared and then gold (Au) was deposited at 15 mA under a vacuum of 10 Pa at room temperature for 30 seconds. As a result of ultrahigh-resolution scanning electron microscope (UHR-SEM) analysis, the gold introduced into the carbon nanotubes had a nanoparticle size of 10 nm or less.

A metal oxide precursor solution containing a metal oxide precursor was prepared to introduce a metal oxide into a carbon nanotube deposited with gold (Au). The metal oxide precursor solution was prepared by mixing ₂ g of the metal oxide precursor Cu (NO ₃ ) ₂ .3H ₂ O and 100 ml of the solvent 15M NaOH.

The thus prepared metal oxide precursor solution was mixed with carbon nanotubes deposited with gold (Au) to prepare a mixed solution, and the mixed solution was heat-treated at 180 ° C for 1 hour.

Thereafter, the heat-treated mixture was dried at 80 DEG C for 24 hours to prepare a metal oxide-carbon electrode composite material.

Comparative Example  One

Pure carbon nanotubes in which the introduction of metal oxide was omitted without depositing gold (Au) were prepared.

Comparative Example  2: gold ( Au Lt; RTI ID = 0.0 > metal-oxide- Carbon electrode material  Manufacture of Composites

A metal oxide-carbon electrode composite material was prepared in the same manner as in Example 1 except that gold (Au) was not deposited.

Comparative Example  3: gold ( Au ) And the production of a carbon electrode material in which the introduction of a metal oxide is omitted

A metal oxide-carbon electrode composite material was prepared in the same manner as in Example 1 except that the introduction of the metal oxide was omitted.

Example  2: gold ( Au Lt; RTI ID = 0.0 > metal-oxide- Carbon electrode material  Using the complex Working electrode  Produce

After 0.05 g of the metal oxide-carbon electrode composite material prepared in Example 1 and 0.02 g of polytetrafluoroethylene (PTFE) were prepared, the metal oxide-carbon nanotube material was placed in 200 ml of a volatile solvent, and the mixture was stitched for 10 minutes Then, the PTFE was added to the PTFE for 1 hour, and a working electrode was prepared through a vacuum filtration process.

Comparative Example  4: gold ( Au ) Deposition and metal oxide introduction process omitted The carbon electrode material  using Working electrode  Produce

Using the pure carbon nanotubes according to Comparative Example 1, a working electrode was prepared in the same manner as in Example 2,

Comparative Example  5: gold ( Au ) The deposition process  The omitted metal oxide- Carbon electrode material  Manufacture of working electrode using composite

A working electrode was prepared in the same manner as in Example 2, except that the metal oxide-carbon electrode composite material prepared in Comparative Example 2 was used.

Comparative Example  6: gold ( Au ) Was deposited and the metal oxide introduction process was omitted The carbon electrode material  using Working electrode  Produce

A working electrode was prepared in the same manner as in Example 2 except that the carbon electrode material prepared in Comparative Example 3 was used.

Carbon electrode material , Metal oxide- Carbon electrode material  Identify the shape and structure of the complex

Using the high resolution field emission scanning electron microscope (UHR-SEM; Hitachi, S-5500) and X-ray diffractometer (XRD; D8 DISCOVER, Bruker AXS, with Cu K radiation) ) Deposited carbon nanotubes and carbon nanotubes not deposited with gold (Au) were confirmed.

The metal oxide-carbon electrode composite material of Example 1 and the metal oxide-carbon composite material of Comparative Example 2 were formed by using a field emission scanning electron microscope (FE-SEM; Hitachi, S-4700) and the same X- The shape and structure of the electrode material composite were confirmed.

3 is a carbon nanotube UHR-SEM image of Comparative Example 1, which is an intermediate product of gold (Au) deposition in Example 1 of the present invention, and FIG. 4 is a UHR-SEM image of a metal oxide- SEM image of the carbon nanotube composite and the metal oxide-carbon nanotube composite of Comparative Example 2.

FIG. 3A is a UHR-SEM image of a general carbon nanotube, and FIG. 3B is a UHR-SEM image of a carbon electrode material on which gold (Au) is deposited as an intermediate product of Example 1 of the present invention. Referring to FIG. 3 (B), it was confirmed that nano-sized gold (Au) particles were uniformly dispersed on the surface of the carbon nanotubes and deposited.

Also, as shown in FIG. 4, it was confirmed that the metal oxide particles introduced into the carbon nanotubes were uniformly formed in a cluster shape.

Nano-clustered CuO  Check presence

The XRD patterns of carbon nanotubes and metal oxide - carbon nanotube composites prepared by various methods were compared.

5 is a graph comparing XRD spectra of the metal oxide-carbon electrode composite material prepared in Example 1 of the present invention and the carbon electrode material prepared in Comparative Examples 1 to 3.

5, it can be seen that, in the case of Example 1, unlike the case of Comparative Example 2 in which the gold (Au) deposition process was not performed, the rotational peaks represented by CuO vary. Specifically, it was confirmed that there was a polycrystal, that is, a nano-cluster type CuO, with 2? Diffraction peaks at 32 °, 35 °, 53 ° and 68 °.

On the other hand, the peak at 26 DEG is the peak of carbon nanotubes, and the peak at 36 DEG, 44 DEG and 65 DEG is the peak of gold (Au). From FIG. 5, it can be confirmed that the material is well formed from a specific diffraction peak for each material.

Glucose  Measurement of current change with concentration

In order to examine the sensitivity and the minimum detection limit of Example 2, Comparative Example 4, Comparative Example 5, and Comparative Example 6, the current change according to the glucose concentration was measured.

6 is a graph showing current response characteristics of Example 2, Comparative Example 4, Comparative Example 5, and Comparative Example 6 of the present invention. 6 is a graph showing the relationship between the working electrodes of Example 2 and Comparative Examples 4 to 6, the reference electrode of the standard calomel electrode, and the counter electrode of the platinum electrode, that is, Using a three-electrode system, the current changes with glucose concentration.

Referring to FIG. 6, it can be seen that as the concentration of glucose increases, the current also increases. However, it can be seen that the current decreases rather than the specific glucose concentration, thereby reducing the space for glucose to react.

In addition, the minimum detection limit, sensitivity, and determination coefficient R ² of Example 2, Comparative Example 4, Comparative Example 5 and Comparative Example 6 were compared, and the results are as follows. Here, the coefficient of determination R ² is the square of the correlation coefficient R, which is a measure for explaining the degree of fit of the regression model. This is a number indicating how many measured values are separated from a straight line. The closer to 1, the higher the accuracy and the smaller the error.

The minimum detection limits of Example 2, Comparative Example 4, Comparative Example 5 and Comparative Example 6 were 0.48 mM, 0.63 mM, 3.15 mM, and 4.83 mM, respectively.

Further, Fig. Referring to the sensitivity of the working electrode from the graph, the slope of 6, Example 2, Comparative Example 4, Comparative Example 5 and Comparative Example 6, sensitivity of each 504.1μA · cm ^-2 · mM ^-1 a, 303.1μA · cm ^{- 2} · mM ^-1, can be identified by a vision ^{152.3μA · cm -2 · mM -1,} 110.4 μA · cm -2 · mM -1. As a result, it was confirmed that the sensitivity of Example 2 was increased by at least four times as compared with Comparative Example 4, Comparative Example 5, and Comparative Example 6.

The sensitivity, minimum detection limit, and R ² of the above-described Example 2, Comparative Example 4, Comparative Example 5 and Comparative Example 6 are summarized in Table 1 below.

Sensitivity, minimum detection limit, R ² compare division responsiveness
(μA · cm ^-2 · mM ^-1 ) Minimum detection limit
(mM) R2 Example 2 504.1 0.48 0.9909 Comparative Example 4 303.1 0.63 0.9607 Comparative Example 5 152.3 3.15 0.9659 Comparative Example 6 110.4 4.83 0.9801

Glucose  Selectivity test of biosensor

The selectivity for glucose detection of the biosensor having the working electrode of Example 2 of the present invention was tested. In general, sucrose, lactose and the like are known to interfere with the electrochemical response during glucose detection using a non-enzyme glucose biosensor.

Specifically, the biosensor including the working electrode, the reference electrode, and the counter electrode of Example 2 was immersed in 0.1 M NaOH electrolyte, and a voltage of 0.8 V was applied to the biosensor. After that, sucrose having a concentration of 0.1 mM, lactose, and glucose having a concentration of 5 mM were sequentially added to the solution, and the current change was measured. The results are shown in Fig.

FIG. 7 shows that the addition of sucrose and lactose resulted in a negligible change in current when the glucose was added. Thus, it was confirmed that the working electrode of Example 2 had excellent glucose selectivity.

Although the present invention has been described with reference to the accompanying drawings and the preferred embodiments described above, the present invention is not limited thereto but is limited by the following claims. Accordingly, those skilled in the art will appreciate that various modifications and changes may be made thereto without departing from the spirit of the following claims.

Claims (10)

(a) depositing gold (Au) on a carbon material to produce a carbon electrode material, and dissolving a metal oxide precursor in a solvent to prepare a metal oxide precursor solution;
(b) mixing the carbon electrode material and the metal oxide precursor solution to prepare a mixed solution; And
(c) heat-treating the mixed solution to prepare a metal oxide-carbon electrode composite material.
The method according to claim 1,
In manufacturing the carbon electrode material by depositing gold (Au) on the carbon material of the step (a)
Wherein the gold (Au) is deposited in an amount of 0.1 to 1 part by weight based on 100 parts by weight of the carbon material.
The method according to claim 1,
The metal oxide _{precursor, Cu (NO 3) 2 ·} 3H 2 O, Cu (CH 3 COO) 2 · H 2 O, CuCl 2 · 2H 2 O, NiSO 4 (H 2 O) 6, NiCl 2 · 6H 2 O, Ni (CH ₃ CO ₂ ) ₂ and Ti {OCH (CH ₃ ) ₂ } ₄ .
The method according to claim 1,
Wherein the carbon electrode material is mixed in an amount of 2 to 10 parts by weight based on 100 parts by weight of the metal oxide precursor in the mixing process of the step (b).
The method according to claim 1,
Wherein the heat treatment is performed at 150 to 200 ° C for 1 to 2 hours. The method for manufacturing a carbon electrode material for a non-enzymatic glucose biosensor according to claim 1,
The method according to claim 1,
The method of claim 1, further comprising washing and drying the metal oxide-carbon electrode composite material after step (c), wherein the drying is performed at 80 to 120 ° C for 24 to 30 hours. A method for manufacturing a carbon electrode material.
A carbon electrode material for a non-enzyme glucose biosensor produced by the method for producing a carbon electrode material for a non-enzyme glucose biosensor according to any one of claims 1 to 6.
(a) preparing a metal oxide-carbon electrode composite material prepared by the method for producing a carbon electrode material for a non-enzyme glucose biosensor according to any one of claims 1 to 6; And
(b) mixing the metal oxide-carbon electrode composite material with a binder and a volatile solvent, followed by filtration under reduced pressure to produce a working electrode.
9. The method of claim 8,
(c) drying the working electrode after the step (b). < Desc / Clms Page number 19 >
10. The method of claim 9,
Wherein the drying is performed at 20 to 120 DEG C for 24 to 30 hours.

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