KR20200011369A - Nonenzymatic determination of glucose at near neutral ph values based on the use of nafion and platinum black coated microneedle electrode array - Google Patents

Abstract

The present invention relates to a microneedle electrode sensor for non-enzymatically measuring blood glucose, a manufacturing method thereof, and a method for non-enzymatically measuring blood glucose. According to the present invention, the microneedle electrode sensor for measuring blood glucose can measure blood glucose non-enzymatically in contrast to an existing enzyme-based microneedle electrode sensor, and can continuously perform monitoring while having improved stability and durability not to cause pain. The method for non-enzymatically measuring blood glucose comprises the steps of: (a) forming a plurality of microneedle shapes on a substrate; (b) coating the entire substrate with a protective agent; and (c) coating a glucose oxidation catalyst on a reaction part of the microneedle formed in a tip part of the microneedle.

Description

Microneedle electrode sensor for measuring blood glucose non-enzymatically and a method for manufacturing the same

The present invention relates to a microneedle electrode sensor capable of measuring blood glucose non-enzymatically, and a method for manufacturing the same. More specifically, blood glucose can be measured non-enzymatically using Pt black, which is a metal catalyst rather than glucose oxidase. It relates to a microneedle electrode sensor that can be.

As of 2018, around 400 million people worldwide suffer from diabetes, with an estimated 600 million by 2035. Blood sugar management is essential for the treatment of diabetes mellitus and prevention of complications. In this case, the most common method for measuring blood glucose is measuring blood glucose by taking a small amount of blood from the fingertip of the patient. However, this has caused problems with trypanophobia in many diabetics, and there have been numerous investigations on alternative methods of measuring blood glucose. Among them, microelectrochemical system (MEMS) technology such as microneedle has been considered as an ideal method for measuring blood glucose without pain. Micro needles are microsized devices that have the ability to penetrate the skin envelope with less pain and can be used in a variety of therapeutic or diagnostic systems. Thus, the microneedle field has been growing rapidly, which has attracted considerable attention because of the potential for delivery and collection into the skin without pain.

Until now, microneedle has been used as a sensor for insulin injection and various analysis. Most applications of microacupuncture have focused on the delivery of minimally invasive, pain-free transdermal drugs, and the microneedle used as a sensor has been primarily focused on the electrical measurement of minimally invasive glucose.

Like the latter, several attempts have been made to use microneedle for the electrical measurement of glucose. Sensors that measure wearable electrical glucose using MEMS technology have been reported, such as smart patches that detect glucose electrically, and devices that detect glucose using electrochemical electrodes combined with enzymes located under the microneedle array. Many glucose sensors have been reported using a base electrochemical sensing method. However, these enzyme-based glucose sensors were easily affected by temperature, PH, humidity, etc., and thus there was a problem of insufficient stability.

On the other hand, unlike the enzyme-based glucose sensor, a glucose sensor that does not use an enzyme has several advantages of high stability, simple manufacturing, high reproducibility of blood glucose measurement, and free from oxygen limitation. And over the last few decades, the sensitivity of glucose measurements has risen considerably as much as enzyme-based sensors. Therefore, non-enzymatic glucose measuring sensor has been suggested as an alternative method for detecting glucose level.

Mo R, Jiang T, Di J, Tai W, Gu Z, (2014) Emerging micro- and nanotechnology based synthetic approaches for insulin delivery. Chem Soc Rev 43 (10): 3595-3629 Yoon Y, Lee GS, Yoo K, Lee J-B, (2013) Fabrication of a microneedle / CNT hierarchical micro / nano surface electrochemical sensors and its in-vitro glucose sensing characterization. Sensors 13 (12): 16672-16681

An object of the present invention is to provide a microneedle electrode sensor capable of measuring blood glucose non-enzymatically, a method for preparing the same, and a method for measuring blood glucose non-enzymatically.

In order to achieve the above object, the present invention provides a method for producing a microneedle electrode sensor for measuring blood glucose non-enzymatically.

The method of manufacturing a microneedle electrode sensor for measuring blood glucose non-enzymatically comprises: (a) forming a plurality of microneedle shapes on a substrate; (b) forming a microneedle by bending a microneedle shape perpendicularly to the substrate; (c) protecting the reaction part of the microneedle positioned at the tip of the formed microneedle and the contact pad of the substrate on which the electrode of the substrate is formed with a protective agent and coating the entire substrate with a protective agent; (d) removing the protective part of the reaction part of the microneedle and the contact pad of the substrate after step (c); And (e) coating a glucose oxidation catalyst on the reaction part of the fine needle from which the protecting agent is removed.

 The step (b) may include plating gold (Au), platinum (Pt), or silver (Ag) on the surface of the microneedle.

The protective agent protecting the reaction zone of the microneedle may be polydimethylsiloxane (PDMS), and the protective agent protecting the contact pad of the substrate may be Parafilm.

The protective agent may be Parylene, and the protective agent may be coated with a thickness of 1 μm or more.

The glucose oxidation catalyst of step (e) may be Pt black, and the coating of the glucose oxidation catalyst may include 2.5% chloroplatinic acid, 0.05% lead acetate, and 0.1M hydrochloric acid (HCl). Electrodeposition solution consisting of) can be used.

In addition, the fine needle electrode sensor serving as a reference electrode may be manufactured by coating silver chloride instead of the glucose oxidation catalyst in step (e).

After the step (e), it may further comprise the step of coating Nafion on top of the glucose oxidation catalyst.

In order to achieve the above another object, the present invention provides a microneedle electrode sensor for non-enzymatically detecting blood glucose.

The microneedle electrode sensor for non-enzymatically detecting blood sugar may include a substrate made of a conductive metal; A plurality of fine needles standing perpendicular to the substrate; A reaction part formed at the tip of the microneedle; A support part connecting the reaction part of the microneedle and the substrate; It includes, wherein the reaction unit is coated with a glucose oxidation catalyst, the support and the substrate may be characterized in that the coating with a protective agent.

The microneedle may be plated with gold (Au), platinum (Pt), or silver (Ag).

The glucose oxidation catalyst may be Pt black.

The protective agent may be parylene, and the protective agent may be coated with a thickness of 1 μm or more.

Instead of the glucose oxidation catalyst, silver chloride may be coated and used as a reference electrode.

The reaction unit may further coat Nafion on top of the glucose oxidation catalyst coating.

In order to achieve the above another object, the present invention can provide a method for detecting blood glucose non-enzymatically measuring the electrical signal of glucose by configuring the microneedle electrode sensor for detecting blood glucose non-enzymatically three electrodes have.

 According to the present invention as described above, unlike the conventional enzyme-based microneedle electrode sensor by producing a microneedle electrode sensor by sequentially coating Pt black and Nafion on the microneedle tip and coating the remaining part with parylene. Enzyme can measure blood glucose and improve stability and durability, so there is no pain and continuous monitoring effect.

1 shows a manufacturing process of the microneedle electrode sensor of the present invention.
2 is a scanning electron microscopy (SEM) image according to Measurement Example 1. FIG.
3 is a cyclic voltammograms (CVs) according to Measurement Example 2;
4 is a linear sweep voltammetry (LSV) according to Measurement Example 3;
5 is a current-time graph according to Measurement Example 4.
6 is a graph of reproducibility according to Measurement Example 5;
7 is a stability graph according to Measurement Example 5.
8 is a current-time graph according to Measurement Example 6.

Hereinafter, the present invention will be described in detail.

In order to achieve the above object, the present invention provides a method for producing a microneedle electrode sensor for measuring blood glucose non-enzymatically.

The method of manufacturing a microneedle electrode sensor for measuring blood glucose non-enzymatically comprises: (a) forming a plurality of microneedle shapes on a substrate; (b) forming a microneedle by bending a microneedle shape perpendicularly to the substrate; (c) protecting the reaction part of the microneedle positioned at the tip of the formed microneedle and the contact pad of the substrate on which the electrode of the substrate is formed with a protective agent and coating the entire substrate with a protective agent; (d) removing the protective part of the reaction part of the microneedle and the contact pad of the substrate after step (c); And (e) coating a glucose oxidation catalyst on the reaction part of the fine needle from which the protecting agent is removed.

 The step (b) may include plating gold (Au), platinum (Pt), or silver (Ag) on the surface of the microneedle.

The protective agent protecting the reaction zone of the microneedle may be polydimethylsiloxane (PDMS), and the protective agent protecting the contact pad of the substrate may be Parafilm.

The protective agent may be parylene, and the protective agent may be coated with a thickness of 1 μm or more.

In addition, the fine needle electrode sensor may be manufactured by coating silver chloride instead of the glucose oxidation catalyst in the step (e), and the prepared fine needle electrode may be used as an Ag / AgCl reference electrode when configuring a three-electrode measurement method.

The glucose oxidation catalyst of step (e) may be platinum black (Pt black), coating the glucose oxidation catalyst is 2.5% chloroplatinic acid and 0.05% lead acetate and the rest The electrodeposition solution consisting of 0.1M hydrochloric acid (HCl) can be used.

By performing the above steps, a Pt black microneedle electrode sensor may be manufactured.

After the step (e), it may further comprise the step of coating Nafion on top of the glucose oxidation catalyst.

By performing the above steps, a Pt black / nafion microneedle electrode sensor may be manufactured.

In more detail, the microneedle electrode sensor capable of measuring blood glucose non-enzymatically prepared by the present invention in step (a) has a plurality of microneedle because the microneedle acts as a working electrode. The formed substrate is a conductive metal material, preferably stainless steel. In addition, a metal having excellent conductivity may be plated and used on the substrate on which the plurality of fine needles are formed, and preferably, gold (Au), platinum (Pt), or silver (Ag) may be plated. In forming the microneedle on the substrate, the microneedle may be formed to stand perpendicular to the substrate surface (90 °). In the case of the plurality of fine needles formed on the substrate, the number may be a plurality of fine needles formed on the substrate in a 3 × 5 array.

In the step (c), the reaction part of the microneedle is protected by a gel type PDMS (polydimethylsiloxane), and the contact pad portion protruding on one side of the substrate on which the plurality of microneedle is formed is coated with Parafilm and then protected and coated. Parylene may be coated as a protective agent on the remaining parts.

The protective agent may have an electrical insulation and a waterproofing effect by coating parylene, and to prevent corrosion or biofouling by substances inside the body during use of the microneedle electrode sensor. The parylene may be coated by chemical vapor deposition (CVD). In general, parylene has a disadvantage in that it is difficult to etch, but the present invention can apply parylene coating without an additional etching process by applying PDMS (polydimethylsiloxane) and parafilm to the parylene coating exclusion part. In addition, the coating thickness of parylene is stable for several days when it is put in a liquid state such as water when it is 1 μm or more, but it should be coated with 1 μm or more because it shows unstable characteristics as soon as it is put in liquid below 1 μm. Most effectively, it is better to be 5 μm or more, but it is preferable to set it within 10 μm because the thin film may be physically disturbed when penetrating the skin.

In step (e), the glucose oxidation catalyst coated on the reaction part of the microneedle may be Pt black. Coating of Pt black used as the oxidation and reduction catalyst of glucose is performed after removing PDMS protecting the reaction part of the microneedle. Specifically, the Pt black coating uses a three-electrode system (Ag / AgCl reference electrode, Pt counter electrode and microneedle working electrode) with a current density of 2.5 mA / m², 2.5% chloroplatinic acid, 0.05% lead acetate. (lead acetate) and 3 mL of solution consisting of 0.1 M hydrochloric acid (HCl). Pt black is a form of platinum powder that is easy to use for electroplating and is a representative material present in excess of available electrode materials. It has high biocompatibility and high catalytic activity against glucose oxidation.

Thus, the use of Pt black allows glucose oxidation to occur without enzymes such as glucose oxidase, minimizing the access of other blockers with co-existing electrical activity. In addition, since it is present in excess, it can be used to reduce the production cost of the microneedle electrode sensor.

And after the step (e) may further comprise the step of further coating Nafion on the surface of the glucose oxidation catalyst-coated microneedle reaction unit. Nafion is a biocompatible substance that acts as a barrier to limit access to the electrode surface (Pt black) for several in vivo signal-interfering substances that are not involved in glucose and blood sugar by electrostatic repulsion. In this case, since a glucose oxidation catalyst such as Pt black is coated on the reaction part of the microneedle, Nafion coating may be performed by a simple method of coating the microneedle reaction part by dipping in a Nafion solution. Specifically, Nafion and ethanol was immersed in a solution of a volume ratio of 1: 6 for 60 seconds, then dried for 40 seconds on a hot plate of 50 ℃, and dried with fresh air for 1 hour at room temperature (24 ℃) Is done.

In order to achieve the above another object, the present invention provides a microneedle electrode sensor for non-enzymatically detecting blood glucose.

The microneedle electrode sensor for non-enzymatically detecting blood sugar may include a substrate made of a conductive metal; A plurality of fine needles standing perpendicular to the substrate; A reaction part formed at the tip of the microneedle; A support part connecting the reaction part of the microneedle and the substrate; It includes, wherein the reaction unit is coated with a glucose oxidation catalyst, the support and the substrate may be characterized in that the coating with a protective agent.

The microneedle may be plated with gold (Au), platinum (Pt), or silver (Ag).

 The protective agent may be parylene, and the protective agent may be coated with a thickness of 1 μm or more.

Instead of the glucose oxidation catalyst, silver chloride may be coated and used as a reference electrode.

Including the above configuration may be a configuration of the Ag / AgCl fine needle reference electrode.

The glucose oxidation catalyst may be Pt black.

Including the above configuration may be a configuration of the Pt microneedle electrode sensor.

The reaction unit may further coat Nafion on top of the glucose oxidation catalyst coating.

Including the above configuration may be a configuration of a Pt black / nafion microneedle electrode sensor.

In order to achieve the above another object, the present invention can provide a method for detecting blood glucose non-enzymatically measuring the electrical signal of glucose by configuring the microneedle electrode sensor for detecting blood glucose non-enzymatically three electrodes have.

The three electrodes include a working electrode, a counter electrode, and a reference electrode, wherein the working electrode includes a Pt black / nafion microneedle electrode sensor and a counter electrode. The counter electrode may use a Pt microneedle electrode sensor, and the reference electrode may use an Ag / AgCl microneedle electrode sensor.

Hereinafter, the present invention will be described in more detail with reference to Examples and Measurement Examples. These examples and measurement examples are only for illustrating the present invention, it will be apparent to those skilled in the art that the scope of the present invention is not to be construed as being limited thereto.

Example 1

The Pt black / nafion microneedle electrode sensor uses a wet ferric chloride (FeCl ₃ ) chemical etchant jet under a pressure of 2 kgf / cm ² for 60 seconds to form the microneedle shape in stainless steel. Formed. Then, a thin layer of gold (Au) was electroplated on the surface of the microneedle and bent at 90 ° using a jig. Thereafter, the tip portion of the microneedle was a gel type PDMS, and the contact pad of the substrate on which the microneedle electrode was formed was protected with parafilmn. Thereafter, 5 μm of parylene was coated on the remaining regions except for the protected portion, and the PDMS and parafilmn were removed, followed by electrodeposition of Pt black on the tip of the microneedle. A three-electrode system (Ag / AgCl reference electrode, Pt counter electrode and microneedle working electrode) was used for electrodeposition of Pt black. Pt black was then electrodeposited using a 3 mL solution consisting of 2.5% chloroplatinic acid, 0.05% lead acetate, and 0.1 M hydrochloric acid (HCl) for 200 seconds at a current density of -2.5 mA / cm ² . It became. And the tip portion of the fine needle electrodeposited with Pt black was supported for 60 seconds in a solution mixed with Nafion and ethanol in a volume ratio of 1: 6. After drying for 40 seconds on a hot plate of 50 ℃, dried for 1 hour at room temperature (24 ℃) with fresh air to prepare a Pt black / nafion microneedle electrode sensor.

Example 2

The Pt microneedle electrode sensor was formed of stainless steel using a wet ferric chloride (FeCl ₃ ) chemical etchant jet under a pressure of 2 kgf / cm ² for 60 seconds. Then, a thin platinum (Pt) layer was electroplated on the surface of the microneedle and bent at 90 ° using a jig. Thereafter, the tip portion of the microneedle was a gel type PDMS, and the contact pad of the substrate on which the microneedle electrode was formed was protected with parafilmn. Then, parylene coating was performed at 5 μm on the remaining areas except for the protected portion.

Example 3

The Ag / AgCl microneedle electrode sensor was formed of stainless steel using a wet ferric chloride (FeCl 3) chemical etchant jet under a pressure of 2 kgf / cm 2 for 60 seconds. Then, a thin layer of silver (Ag) was electroplated on the surface of the microneedle and bent at 90 ° using a jig. Thereafter, the tip portion of the microneedle was a gel type PDMS, and the contact pad of the substrate on which the microneedle electrode was formed was protected with parafilmn. After the parylene coating at 5 μm in the remaining region except for the protected portion, the PDMS and parafilmn were removed, and AgCl (silver chloride) coating was applied to the microneedle tip to prepare Ag / AgCl microneedle electrode sensors. .

Measurement Example 1.

Scanning electron microscopy (SEM) images show that the surface of the microneedle, whose surface is not plated with gold, is flat, but after sequential plating of gold (Au) and Pt black, the surface becomes rough and porous. (FIG. 2A) Finally, as in the microneedle electrode sensor manufactured in Example 1, Nafion is coated on a microneedle plated with Pt black, the surface of the microneedle reaction part in which a thin film is formed can be observed. (FIG. 2B)

Measurement Example 2.

The Pt black / nafion microneedle electrode prepared in Example 1 was a working electrode, the Pt microneedle electrode prepared in Example 2 was a counter electrode, and the Ag / AgCl prepared in Example 3 The microneedle electrode was used as a reference electrode to measure the voltage current. Specifically, a two-electrode system consisting of a working electrode, a counter electrode, and a reference electrode (FIG. 3A) and a two consisting of a working electrode and a reference electrode only. Under the electrode system (FIG. 3B), cyclic voltammograms (CVs) were recorded using buffered saline (pH 7.4) at a scan rate of 50 mV / s in the 0.7 to 0.4 V voltage range. 3A and 3B, the Pt black microneedle electrode showed a cyclic voltage-current graph of a typical Pt, showing a higher redox peak compared to the microneedle electrode without Pt black plating. . This is because the impedance of the electrode decreases as the reactive area of the electrode increases due to Pt black. In the case of Nafion-coated (Pt black / nafion microneedle electrode), the anodic peak current increased slightly at 0.12 V (12% and 40% respectively in FIGS. 3A and 3B), but significantly at -0.37 V. Reductions (143% and 49% in FIGS. 3A and 3B, respectively). However, no change in the anodic peak voltage was found. This means that even after the formation of the Nafion film, the characteristics of the microneedle electrode sensor measuring the redox current were not lost.

Measurement Example 3.

The Pt black / nafion microneedle electrode prepared in Example 1 was a working electrode, the Pt microneedle electrode prepared in Example 2 was a counter electrode, and the Ag / AgCl prepared in Example 3 The microneedle electrode is used as a reference electrode to 50 mV of various concentrations of glucose (0 to 30 mM) present in buffered saline at pH 7.4 under a three-electrode system (FIG. 4A) and a two-electrode system (FIG. 4B). Voltage current was measured at a scan rate of / s and a linear sweep voltammetry (LSV) thereof is shown in FIG. 4. The current peak at -0.37 V is due to the adsorbed intermediate formed for the electrosorption of glucose (adsorption-desorption zone of hydrogen: -1.0 V to -0.6 V) and the second peak at -0.12 V and +0.12 V The third peak at corresponds to the direct oxidation of glucose at the electrode surface (glucose oxidation region: -0.4 V to +0.6 V).

 As the glucose concentration increased, the current peak due to glucose oxidation increased at the above-mentioned voltages. The optimum voltage for glucose oxidation was chosen as +0.12 V, and this low overvoltage enabled unobstructed measurements.

In the case of glucose measurement voltage, conventional non-enzymatic electrochemical glucose sensors require a high voltage (about +0.6 V) while the sensor of the present invention requires a low measurement voltage of +0.12 V. This reduction in voltage makes it possible to safely perform in vivo analysis and has the effect of reducing the power consumption of the portable sensor.

Measurement Example 4.

 After adding glucose continuously at intervals of 100 seconds by +0.12 V, the Pt black / nafion microneedle electrode prepared in Example 1 was a working electrode, and the Pt microneedle electrode prepared in Example 2 As an electrode (counter electrode), the Ag / AgCl microneedle electrode prepared in Example 3 was used as a reference electrode to measure the current-time. In the three-electrode system (FIG. 5A), the anodic current increased linearly with increasing glucose concentration and reached saturation at 40 mM. In a two-electrode system (FIG. 5B) the saturation was reached at 20 mM.

The electrodes exhibit a measurement sensitivity of 175 ± 0.84 μA / mM · cm 2 and 205.57 ± 0.84 μA / mM · cm 2, respectively, over a wide dynamic range of 1-40 mM in a three-electrode system and 4-20 mM in a two-electrode system. The response time of the sensor is 2 seconds, and the limits of detection (DL) of glucose correspond to 23 ± 2.0 μm and 6.0 ± 1.0 μm, respectively, in the 3- and 2-electrode systems. DL values are treated the same as measurement sensitivity. This is actually higher than the upper limit of measurement concentration and measurement sensitivity of existing non-enzymatic electrochemical glucose sensors.

The high linearity results observed over a wide concentration range demonstrated the high reproducible electrochemical behavior of the sensors fabricated for the glucose being measured (FIG. 5C, FIG. 5D) and in this case the measured glucose concentration ranges were determined physiologically and pathologically. This range includes glucose concentrations, indicating the diagnostic value of the microneedle sensor for future use as a glucose sensor. And relative analysis of sensor performance showed that the 3-electrode system (FIG. 5C) had a better linear range, moderate sensitivity and DL than the 2-electrode system (FIG. 5D).

Measurement Example 5.

 The reproducibility of the microneedle electrodes prepared by the preparation method of Examples 1 to 3 was evaluated from the response to various glucose concentrations. The Pt black / nafion microneedle electrode prepared in Example 1 was a working electrode, the Pt microneedle electrode prepared in Example 2 was a counter electrode, and the Ag / AgCl prepared in Example 3 The microneedle electrode showed 3.2% relative deviation and acceptable acceptable reproducibility when glucose was added to 0.1 M PBS buffer (pH7.4) continuously in a three-electrode system that was used as a reference electrode. (FIG. 6)

Stability was achieved by continuously adding and measuring glucose in a concentration range of 4-8 mM in 0.1 M PBS buffer (pH 7.4) under constant voltage of +0.12 V for 5 hours. The result proves that 60% of the initial activity of the sensor is still maintained at the end of 12 consecutive measurements (Figs. 7 A, B).

 On the other hand, existing non-enzymatic electrochemical glucose sensors can be measured in the same basic environment as in NaOH solution, and for this reason, it is not easy to use non-enzymatic sensors in actual sample analysis. However, in the case of the sensor based on Pt black / nafion as in the present invention, it is possible to analyze in a neutral environment, so it is easy to analyze the actual sample.

Measurement Example 6.

 In order to confirm the glucose selectivity of the microneedle electrode sensor manufactured by the preparation method of Examples 1 to 3, interfering substances in actual blood samples, namely AA, DP, AP, LA and UA (AA: ascorbic acid, The effects of LA: lactic acid, UA: uric acid, DP: dopamine, and AP: acetaminophen were studied. The concentrations of obstructions used in the investigation were 10 times higher than normal physiological levels. FIG. 8 shows the presence of an obstruction using a Pt black / nafion microneedle electrode sensor under 0.12 V of the 3-electrode system (FIG. 8A) and the 2-electrode system (FIG. 8B) (glucose concentration is 2 mM, obstruction concentration is 0.1 mM). The experimental results appear in. As a result, it was clear that the addition of any obstruction had a negligible effect on the detection of glucose. This negligible effect of the obstructions was due to the limited access of the obstructions to the microneedle electrode surface due to the electrostatic repulsion caused by Nafion. And the detection of glucose free from these blockages reflects a strong and selective electrocatalytic activity for glucose detection of Pt.

Measurement Example 7

Using the standard method of adding the concentration of glucose present in the three different blood samples (A, B, and C) under 0.12V, the microneedle prepared in the manufacturing method of Examples 1 to 3 As a control, it was measured using a commercial glucometer (glucometer). The results are shown in the table below.

 Microneedle electrode sensors of Examples 1 to 3 Commercial glucometer A 3.8 ± 0.14 mM 4.0 ± 0.016 mM B 5.1 ± 0.21 mM 5.2 ± 0.012 mM C 4.7 ± 0.17 mM 4.5 ± 0.031 mM

This shows that there is no significant difference between the two measured values. Compatibility between these volumetric measurements demonstrates confidence in measuring glucose using the sensor of the present invention on real blood samples. These studies indicate that the sensor of the present invention can be used for the analysis of sensitive and quantitative glucose in real samples.

As mentioned above, specific portions of the present invention have been described in detail, and it should be apparent to those skilled in the art that such specific descriptions are merely preferred embodiments, and thus the scope of the present invention is not limited thereto. will be. Thus, the substantial scope of the present invention will be defined by the appended claims and their equivalents.

Claims (20)

In manufacturing a microneedle electrode sensor for measuring blood sugar,
(a) forming a plurality of microneedle shapes on the substrate;
(b) coating the entire substrate with a protective agent; And
(c) manufacturing a microneedle electrode sensor for non-enzymatically measuring blood glucose, comprising coating a glucose oxidation catalyst on the reaction part of the microneedle formed at the tip of the microneedle. Way.
The method of claim 1,
The step (a) further comprises the step of plating the substrate with a conductive metal,
The conductive metal is gold (Au), platinum (Pt), or silver (Ag) method for producing a microneedle electrode sensor for measuring blood glucose non-enzymatically characterized in that.
The method of claim 2,
And bending the microneedle shape vertically with respect to the plated substrate to form a microneedle, wherein the microneedle electrode sensor is non-enzymatically measuring blood glucose.
The method of claim 3,
The microneedle electrode for measuring blood glucose non-enzymatically further comprising the step of protecting the reaction portion of the microneedle located in the tip of the microneedle and the contact pad of the substrate on which the electrode of the substrate is formed with a protective agent. How to make a sensor.
The method of claim 4, wherein
The protective agent for protecting the reaction portion of the microneedle is PDMS (Polydimethylsiloxane), the protective agent for protecting the contact pad of the substrate is a method for producing a microneedle electrode sensor for measuring blood glucose non-enzymatically characterized in that the Parafilm .
The method of claim 5,
The step (b) of the protective agent is a method for producing a microneedle electrode sensor for measuring blood glucose non-enzymatically characterized in that the parylene.
The method of claim 6,
The step (b) of the protective agent is a method for producing a microneedle electrode sensor for measuring blood glucose non-enzymatically characterized in that the coating to a thickness of 1μm or more.
The method of claim 7, wherein
The method of manufacturing a microneedle electrode sensor for measuring blood glucose non-enzymatically further comprising the step of removing the protective part of the reaction pad and the contact pad of the substrate after the step (b) coating the protective agent. .
The method of claim 8,
The glucose oxidation catalyst of step (c) is platinum black (Platinum black, Pt black) characterized in that the method for producing a microneedle electrode sensor for measuring blood glucose non-enzymatically.
The method of claim 7, wherein
The method of manufacturing a microneedle electrode sensor for measuring blood glucose non-enzymatically characterized in that the reference electrode is prepared by coating silver chloride instead of the glucose oxidation catalyst in step (c).
The method of claim 9,
After the step (c), the method of manufacturing a microneedle electrode sensor for measuring blood glucose non-enzymatically characterized in that it further comprises the step of coating Nafion on top of the glucose oxidation catalyst.
A substrate made of a conductive metal; A plurality of fine needles standing perpendicular to the substrate; A reaction part formed at the tip of the microneedle; A support part connecting the reaction part of the microneedle and the substrate; Including,
The reaction unit is coated with a glucose oxidation catalyst,
The support and the substrate is a microneedle electrode sensor for detecting blood glucose non-enzymatically characterized in that the coating with a protective agent.
The method of claim 12,
The surface of the substrate and the microneedle is a microneedle electrode sensor for detecting blood glucose non-enzymatically characterized in that the plated with a conductive metal.
The method of claim 13,
The conductive metal is gold (Au), platinum (Pt), silver (Ag) microneedle electrode sensor for detecting blood glucose non-enzymatically characterized in that.
The method of claim 14,
The protective agent is a microneedle electrode sensor for non-enzymatically detecting blood glucose, characterized in that parylene.
The method of claim 15,
The protective agent is a microneedle electrode sensor for non-enzymatically detecting blood glucose, characterized in that the coating is coated in a thickness of 1μm or more.
The method of claim 16,
The glucose oxidation catalyst is a non-enzymatic microneedle electrode sensor characterized in that the platinum black (Pt black).
The method of claim 17,
The reaction unit is a microneedle electrode sensor for detecting blood glucose non-enzymatically characterized in that the Nafion is further coated on top of the glucose oxidation catalyst coating.
The method of claim 16,
The microneedle electrode sensor for detecting blood glucose non-enzymatically, characterized in that the coating can be used as a reference electrode instead of the glucose oxidation catalyst.
20. A method for detecting blood glucose non-enzymatically by measuring the electrical signal of glucose by configuring the microneedle electrode sensor according to claim 17, 18 and 19 in a three- or two-electrode measuring method.

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