KR20220006978A - High sensitive sensor for measuring glucose and method of the same - Google Patents

Abstract

The present invention relates to an electrochemical high-sensitivity glucose measurement sensor and a manufacturing method thereof. According to the present invention, the electrochemical high-sensitivity glucose measurement sensor comprises: electrodes; an active layer laminated on the electrodes and including an enzyme; and a polymer layer laminated on the active layer and including a polymer having a structure of the structural formula 1, wherein n is a positive integer. Accordingly, the polymer layer prevents inflow of interfering substances except for sugar in a sample containing sugar, and thus only sugar can be selectively detected and quantitative measurement thereof is possible.

Description

HIGH SENSITIVE SENSOR FOR MEASURING GLUCOSE AND METHOD OF THE SAME

The present invention relates to a glucose sensor and a manufacturing method thereof, and more particularly, to a glucose measuring sensor capable of selectively measuring glucose in urine and a manufacturing method thereof.

Diabetes mellitus is characterized by hyperglycemia in which the concentration of blood glucose is increased due to abnormal insulin action or insulin secretion defect, and causes acute complications or chronic complications related to damage to human tissues due to diabetes. Recently, the number of diabetic patients is increasing in Korea as well. As a result of analysis of medical expenses data by the National Health Insurance Corporation, the number of diabetic patients increased by 23.9% from 1.63 million in 2006 to 2.02 million in 2010. According to the nutritional survey data, it was analyzed that 1 in 10 adults over the age of 30 had diabetes.

A very important factor in managing and treating diabetes is to manage blood sugar by periodically measuring and monitoring blood sugar. A representative blood sugar device currently on the market for blood sugar management consists of a blood sugar device that displays blood sugar information, a test strip on which blood is placed, and a blood sampler used to collect blood. Although the blood glucose device of the blood glucose meter can be used for a long time, there is a disadvantage that the blood glucose strip (test strip) and the blood sampler, which are parts that detect blood to measure blood glucose, must be used once and then thrown away.

A commonly used method for measuring blood sugar is to collect a small amount of blood from the capillaries at the tip of the finger and apply the blood to a test strip for measurement. The test strip, that is, the blood sugar strip, contains an enzyme that reacts with blood sugar in the blood, and the blood sugar is detected through an electrochemical reaction using the enzyme. However, the blood sampling method for collecting a small amount of blood from the fingertip for blood sugar control is reluctant due to the side effects of patients feeling fear and pain at the fingertip easily. In addition, since there is a medical risk of infection, many researchers have been conducting research on blood glucose measurement for a long time rather than a blood glucose measurement method through blood collection.

Among them, in a method using urine, which is a representative method for measuring blood glucose without blood, glucose measurement may be performed using a strip-based urine glucose sensor. However, the urine glucose sensor is a simple sensor that estimates the quantity by comparing the color change with a standard color, and there is a problem in that there is no information on the quantitative concentration of sugar during actual urination, and it is difficult to secure an accurate quantitative value.

It is an object of the present invention to provide a high-sensitivity glucose sensor capable of selectively measuring only sugar in urine, including a member capable of blocking substances other than sugar in urine.

Another object of the present invention is to provide a high-sensitivity glucose measurement sensor capable of quantitatively measuring sugar.

Another object of the present invention is to provide a method for manufacturing a high-sensitivity glucose measurement sensor including a layer capable of blocking substances other than sugar in urine to selectively measure glucose.

A high-sensitivity glucose sensor for one purpose of the present invention includes an electrode, an active layer laminated on the electrode and containing an enzyme, and a polymer layer laminated on the active layer and including a polymer having a structure of the following Structural Formula 1:

<Structural formula 1>

In Structural Formula 1, n is a positive integer.

In one embodiment, the polymer comprises 1H,1H,2H,2H-perfluorodecyl methacrylate (1H,1H,2H,2H-perfluorodecyl polyacrylate, PDA) and cyclohexyl methacrylate (CHMA). may be a bonded polymer.

In one embodiment, the enzyme may be a glucose oxidase.

In an embodiment, the active layer may include glutaraldehyde (GA).

In one embodiment, the active layer may further include albumin (Bovine serum albumin, BSA).

A method for manufacturing a high-sensitivity glucose sensor for another purpose of the present invention comprises a first step of forming an active layer by coating an active solution containing an enzyme on an electrode, an initiator in a solvent, 1H, 1H, 2H, 2H-perfluoro A second step of synthesizing a polymer having the structure of Structural Formula 1 by adding and polymerizing decyl methacrylate (1H, 1H, 2H, 2H-perfluorodecyl polyacrylate, PDA) and cyclohexyl methacrylate (CHMA); and a third step of forming a polymer layer by applying the synthesized polymer on the active layer:

<Structural formula 1>

In Structural Formula 1, n is a positive integer.

In one embodiment, the enzyme may be glucose oxidase (glucose oxidase).

In an embodiment, the active layer may include glutaraldehyde (GA).

In one embodiment, the active layer may further include albumin (Bovine serum albumin, BSA).

In an embodiment, the initiator may be azobisisobutyronitrile (AIBN).

In an embodiment, the solvent may be trifluorotoluene (α,α,α-trifluorotoluene, TFT).

According to the present invention, by applying a polymer layer that can block substances other than sugar, it is possible to selectively detect only glucose in urination, and quantitative measurement of the detected sugar is possible, so that it can have high accuracy, and damage to the sensor This has the effect of prolonging the life of the sensor.

In addition, since it is easy to clean, the risk of infection and contamination of the sugar measuring sensor is small, it can be reused repeatedly, and it is very economical because it enables continuous measurement, and it has the advantages of very easy storage.

1 and 2 are views for explaining the polymer layer synthesis of the present invention.
3 is a view showing the glucose measurement results of the active layer of the present invention.
4 is a view showing repeated measurement results _{of hydrogen peroxide (H 2} O ₂ ) of the sensor including the polymer layer of the present invention.
5 is a view showing measurement results according to glucose concentration using a glucose measurement sensor manufactured according to an embodiment of the present invention.
6 is a view showing the results of a stability test according to a storage period using a sugar measuring sensor manufactured according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Since the present invention can have various changes and can have various forms, specific embodiments are illustrated in the drawings and described in detail in the text. However, this is not intended to limit the present invention to the specific disclosed form, it should be understood to include all modifications, equivalents and substitutes included in the spirit and scope of the present invention. In describing each figure, like reference numerals have been used for like elements.

The terminology used in the present application is only used to describe specific embodiments and is not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly dictates otherwise. In the present application, terms such as “comprise” or “have” are intended to designate that a feature, step, operation, component, part, or combination thereof described in the specification is present, and includes one or more other features or steps. , it should be understood that it does not preclude the possibility of the existence or addition of an operation, a component, a part, or a combination thereof.

Unless defined otherwise, all terms used herein, including technical and scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and should not be interpreted in an ideal or excessively formal meaning unless explicitly defined in the present application. does not

The present invention relates to a glucose sensor, which is an electrochemical biosensor that can selectively measure only glucose (glucose) present in urine, and includes ascorbic acid, uric acid, etc. excluding glucose in urine. It is characterized by including a layer capable of blocking the same other materials.

The high-sensitivity glucose sensor and method for manufacturing the same of the present invention may include an electrode, an active layer formed on the electrode, and a polymer layer formed on the active layer and capable of blocking impurities other than sugar from entering the electrode.

If the electrode is formed of a material having sufficient electrical conductivity to measure a current, there is no particular limitation on the type of material forming the electrode. Preferably, the electrode is a carbon electrode (graphite electrode, CNT electrode, etc.) containing a metal material such as gold (Au), platinum (Pt), silver (Ag), copper (Cu), a conductive polymer, and carbon. can be formed.

The active layer is a layer capable of oxidizing glucose and may be laminated on the electrode. The active layer may be formed of a material including an enzyme to oxidize glucose, for example, the enzyme may be a glucose oxidase.

In one embodiment, the active layer may include glutaraldehyde (GA). The glutaraldehyde may maximize the amount of enzyme immobilization by mutually binding the enzymes included in the active layer as a crosslinker.

In addition, the active layer may additionally include a protein together with glutaraldehyde. For example, the protein may be a protein such as bovine serum albumin (BSA) or ovalbumin.

In another embodiment, the active layer may include glutaraldehyde and bovine serum albumin (BSA). The albumin (Bovine serum albumin, BSA) can increase the stability of the enzyme.

The glucose oxidase is an enzyme that catalyzes the reaction of glucose into gluconic acid. When glucose is exposed to glucose oxidase, the glucose is oxidized by the glucose oxidase to produce gluconic acid. At this time, oxygen may be easily reduced to _{hydrogen peroxide (H 2} O ₂ ) due to its high reducing power. In summary, while glucose reacts with glucose oxidase, oxidation of glucose and reduction of oxygen occur simultaneously to produce _{gluconic acid and hydrogen peroxide (H 2} O _{2 ).} In general, most glucose sensors _{measure glucose by measuring the amount of hydrogen peroxide (H 2} O ₂ ) generated through the reaction or by measuring the amount of oxygen consumed.

In the present invention, by using the fact that glucose oxidase is reversibly changed into oxidation and reduction forms in the reaction of glucose and performs only the catalytic role of the reaction, and it accompanies the movement of electrons in the process of restoring it back to its original state, Glucose can be quantified and measured by measuring the amount of charge through movement.

The active layer may be laminated by applying an active solution containing an enzyme on the electrode. The active solution may be a solution in which gelation is in progress. The active layer using the active solution may be formed using a spin coater. However, the present invention is not necessarily limited thereto. The thickness of the active layer is not particularly limited, and may be adjusted to a thickness suitable for a necessary situation.

In one embodiment, the active solution may contain glutaraldehyde (GA). The glutaraldehyde may be added to immobilize an enzyme included in the active layer as a crosslinker.

In addition, the active solution containing glutaraldehyde may further contain a protein. For example, the protein may be a substance such as albumin (Bovine serum albumin, BSA) or ovalbumin.

In one embodiment, the active solution may include glutaraldehyde and bovine serum albumin (BSA). The albumin (Bovine serum albumin, BSA) may be added to increase the stability of the enzyme.

The polymer layer is a layer that blocks all substances except sugar in urine, and may be laminated on the active layer. The polymer layer may be prepared by including a polymer having a structure of Structural Formula 1 below.

<Structural formula 1>

In Structural Formula 1, n is a positive integer.

The polymer having the structure of Structural Formula 1 is 1H,1H,2H,2H-perfluorodecyl methacrylate (1H,1H,2H,2H-perfluorodecyl polyacrylate, PDA) and cyclohexyl methacrylate (CHMA) It can be prepared by polymerization.

Hereinafter, it will be described in more detail with reference to FIGS. 1 and 2 showing the structure of perfluorodecyl methacrylate for the synthesis of the polymer and the synthesis of the polymer layer.

1 and 2 , in one embodiment, the polymer comprises an initiator in a solvent, 1H,1H,2H,2H-perfluorodecyl methacrylate (1H,1H,2H,2H-perfluorodecyl polyacrylate, PDA) and It can be prepared by adding and polymerizing cyclohexyl methacrylate (CHMA).

The initiator is an initiator of a polymerization reaction, and refers to a material capable of first forming radicals in a monomer to be polymerized. For example, the initiator may be azobisisobutyronitrile (AIBN).

The solvent means a material capable of dissolving materials for a polymerization reaction. For example, the solvent may be trifluorotoluene (α,α,α-trifluorotoluene, TFT).

Polymerization of the polymer is not particularly limited as long as the conditions for polymer polymerization can be sufficiently performed, and in one embodiment, the polymerization may be performed at about 72° C. for 6 hours.

The polymer layer may be formed using a solution obtained by dissolving the polymerized polymer in an organic solvent. The organic solvent is not particularly limited as long as it is an organic solvent capable of dissolving the polymerized polymer, and for example, acetone or alcohol may be used. The formation of the polymer layer may be performed using a spin coater, but is not limited thereto, and any method capable of coating the polymer layer on the active layer may be used.

According to the present invention, by providing a polymer layer that can block substances other than sugar from entering the sensor in urine, damage to the sensor is prevented, and a sensor with high sensitivity is provided by selectively detecting and measuring only sugar can do.

Hereinafter, the high-sensitivity glucose measurement sensor of the present invention and a manufacturing method thereof will be described in more detail through specific examples. However, the embodiments of the present invention are merely some embodiments of the present invention, and the scope of the present invention is not limited to the following examples.

Example

Electrode/Active Layer Manufacturing

An active layer, which is a glucose detection layer for detecting glucose, was laminated on the electrode. First, a mixed solution is prepared by mixing a glutaraldehyde (GA) solution, an enzyme (Enzyem) and a bovine serum albumin (BSA) solution, and after a certain period of time, the mixed solution becomes a gel. It was produced using the phenomenon. After the preparation of the mixed solution, the mixed solution, in which gelation proceeds after about 1 minute, was applied and laminated to have a constant thickness on the front surface of the electrode using a spin coater. A structure (electrode/active layer) was prepared.

Glucose having concentrations of 0, 31.25, 62.5, 125, 250, 500, and 1000 mg/dl was detected by an electrochemical method using the structure (electrode/active layer) prepared above, and the results are shown in FIG. 3 .

Referring to FIG. 3 , it can be confirmed that glucose can be detected according to the concentration by the active layer.

Electrode/Polymer Layer Manufacturing

A polymer layer to block interfering substances except for sugar in urine (urination) was laminated on the electrode. 1H,1H,2H,2H-perfluorodecyl methacrylate (1H,1H,2H,2H-perfluorodecyl polyacrylate, PDA), cyclohexyl methacrylate (CHMA), trifluorotoluene (α,α) ,α-trifluorotoluene, TFT) and azobisisobutyronitrile (AIBN) were mixed, and polymerization was performed at 72° C. for 6 hours to synthesize P (FDA-r-CHMA). After dissolving the synthesized P(FDA-r-CHMA) in an organic solvent and applying it to the entire electrode using a spin coater, the P(FDA-r-CHMA) polymer layer was applied on the electrode through immobilization for 30 minutes. A laminated structure (electrode/polymer layer) was prepared.

Repeat measurement ability _{of hydrogen peroxide (H 2} O ₂ ), a reaction product after glucose and glucose oxidase reaction, was evaluated using the structure (electrode/polymer layer) prepared above. The results are shown in FIG. 4 .

Referring to FIG. 4 , it was confirmed that the P (FDA-r-CHMA) polymer layer was maintained without disappearing even during repeated measurement, and it was confirmed that only the reaction of the reactant, hydrogen peroxide (H ₂ O ₂ ) can be measured. have.

Electrode/active layer/polymer layer manufacturing

By performing the same process as the process of laminating a polymer layer in the preparation of the structure (electrode/polymer layer) on the structure (electrode/active layer) prepared above, the high-sensitivity glucose measurement sensor according to an embodiment of the present invention ( electrode/active layer/polymer layer) was prepared.

For the selective glucose detection test of the glucose sensor, the glucose detection ability was tested using urine having a glucose concentration of 0, 31.25, 62.5, 125, 250, 500, and 1000 mg/dl, respectively, and the results are shown in FIG. showed

Referring to FIG. 5 , it can be confirmed that the sensor can detect glucose according to each glucose concentration in the urine.

In addition, by storing the high-sensitivity glucose measurement sensor (electrode/active layer/polymer layer) in general tap water for 7 days, the stability ability of the sensor according to the storage period was evaluated, and the results are shown in FIG. 6 .

Referring to FIG. 6 , it can be confirmed that the sensor of the present invention can measure glucose even after 7 days have elapsed. Although the above has been described with reference to the preferred embodiment of the present invention, those skilled in the art will recognize the following patents It will be understood that various modifications and variations of the present invention can be made without departing from the spirit and scope of the invention as set forth in the appended claims.

Claims (11)

electrode;
an active layer laminated on the electrode and including an enzyme; and
A polymer layer laminated on the active layer and comprising a polymer having a structure of the following Structural Formula 1,
High Sensitivity Per Measurement Sensor:
<Structural formula 1>

In Structural Formula 1, n is a positive integer.
According to claim 1,
The polymer is a polymer in which 1H,1H,2H,2H-perfluorodecyl methacrylate (1H,1H,2H,2H-perfluorodecyl polyacrylate, PDA) and cyclohexyl methacrylate (CHMA) are combined. characterized,
High sensitivity per measurement sensor.
According to claim 1,
The enzyme is glucose oxidase,
High sensitivity per measurement sensor.
According to claim 1,
The active layer is characterized in that it contains glutaraldehyde (GA),
High sensitivity per measurement sensor.
5. The method of claim 4,
The active layer is characterized in that it further comprises albumin (Bovine serum albumin, BSA),
High sensitivity per measurement sensor.
A first step of forming an active layer by applying an active solution containing an enzyme on the electrode;
Initiator, 1H,1H,2H,2H-perfluorodecyl methacrylate (1H,1H,2H,2H-perfluorodecyl polyacrylate, PDA) and cyclohexyl methacrylate (CHMA) are added to the solvent and polymerized a second step of synthesizing a polymer having a structure of the following Structural Formula 1; and
A third step of forming a polymer layer by applying the synthesized polymer on the active layer;
Method for manufacturing high-sensitivity glucose measurement sensor:
<Structural formula 1>

In Structural Formula 1, n is a positive integer.
7. The method of claim 6,
The enzyme is glucose oxidase,
High-sensitivity per-measurement sensor.
7. The method of claim 6,
The active layer is characterized in that it contains glutaraldehyde (GA),
A method for manufacturing a high-sensitivity glucose measurement sensor.
7. The method of claim 6,
The active layer is characterized in that it further comprises albumin (Bovine serum albumin, BSA),
High-sensitivity per-measurement sensor.
7. The method of claim 6,
The initiator is azobisisobutyronitrile (AIBN),
A method for manufacturing a high-sensitivity glucose measurement sensor.
7. The method of claim 6,
The solvent is trifluorotoluene (α, α, α-trifluorotoluene, TFT),
A method for manufacturing a high-sensitivity glucose measurement sensor.

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