Graphene film sensor, glucose sensor based thereon and preparation method thereof

Abstract

The present invention discloses a graphene film sensor, a glucose sensor based thereon and a preparation method thereof, wherein the graphene film sensor is prepared by the following method: 1) processing material preparation: providing a processing material having a PI film; 2) electrode processing: introducing the drawn electrode pattern into a carbon dioxide laser cutting machine to process the processing material; then dissolving the water-soluble adhesive tape between the PI film and the glass sheet, and then removing the glass sheet to obtain the graphene film sensor. The present invention uses carbon dioxide laser cutting to form dense and porous graphene to prepare a graphene film sensor, and further prepares a thin-film glucose sensor, which can realize non-invasive detection of blood sugar; the thin-film sensor obtained by the laser cutting method has low requirements on the sensor processing environment, fast processing speed, and low processing cost, which can meet the requirements of time-saving and cost-saving for large-scale processing, and at the same time, the laser cutting operation is simple and the operation process is easy to control.

Description

Technical Field

[0001] The present invention relates to the field of detection technology, and in particular to a graphene film sensor, a glucose sensor based thereon and a preparation method thereof. Background Art

[0002] The quantitative determination of glucose is of great significance in biochemistry, clinical chemistry and food analysis. Biosensors have many advantages in the measurement of glucose and are widely used. For example, patent CN107727723A discloses a skin-like ultra-thin flexible glucose measurement sensor and its preparation method. The sensor provided by the patent has the characteristics of ultra-thin flexibility and can be attached to any position on the surface of human skin. Without affecting human movement and normal life, it can non-invasively and accurately measure the concentration of glucose on the skin surface, thereby realizing non-invasive monitoring of blood sugar in diabetic patients. However, it has the following shortcomings: the method used in the processing of the working electrode is relatively complicated, which is not conducive to industrialization. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a graphene film sensor, a glucose sensor based thereon and a preparation method thereof in view of the deficiencies in the above-mentioned prior art.

[0004] In order to solve the above technical problems, the technical solution adopted by the present invention is: a graphene film sensor, which is prepared by the following method:

[0005] 1) Processing material preparation:

[0006] 1.1) Take a glass slide, wash it, and stick double-sided tape on one side of the glass slide;

[0007] 1.2) Stick the non-adhesive side of the water-soluble adhesive tape on the double-sided adhesive tape of the glass sheet until the double-sided adhesive tape is fully applied;

[0008] 1.3) Tear off the protective layer on the surface of the hydrosol tape to expose the sticky surface;

[0009] 1.4) cutting the PI film into the same size as the glass sheet, and then attaching it to the sticky surface of the water-soluble adhesive tape to obtain a processed material;

[0010] 2) Electrode processing:

[0011] 2.1) Draw the required electrode pattern and import the electrode pattern into the CO2 laser cutting machine;

[0012] 2.2) processing the processed material obtained in step 1) by a carbon dioxide laser cutting machine according to the electrode pattern to obtain a primary product;

[0013] 2.3) placing the initial product in water to dissolve the water-soluble adhesive tape between the PI film and the glass sheet in the initial product, and then separating the PI film from the glass sheet and discarding the glass sheet to obtain the graphene film sensor.

[0014] Preferably, the step 1) specifically includes:

[0015] 1.1) Take a glass slide, wash it with deionized water, and stick double-sided tape on one side of the glass slide;

[0016] 1.2) Stick the non-adhesive side of the water-soluble adhesive tape on the double-sided adhesive tape of the glass sheet until the double-sided adhesive tape is fully applied;

[0017] 1.3) Tear off the protective layer on the surface of the hydrosol tape to expose the sticky surface;

[0018] 1.4) Cut a PI film with a thickness of 0.05-0.5 mm into the same size as the glass sheet, and then attach it to the sticky surface of the water-soluble adhesive tape. Ensure that there are no bubbles between the PI film and the water-soluble adhesive tape during attachment to obtain a processed material.

[0019] Preferably, the step 2) specifically comprises:

[0020] 2.1) Draw the required electrode pattern in the CAD software, import the electrode pattern into the CO2 laser cutting machine, set the processing parameters: power 5%, speed 7%, PPI1000, and process in the form of raster;

[0021] 2.2) processing the processed material obtained in step 1) by a carbon dioxide laser cutting machine according to the electrode pattern to obtain a primary product;

[0022] 2.3) placing the initial product in water to dissolve the water-soluble adhesive tape between the PI film and the glass sheet in the initial product, and then separating the PI film from the glass sheet and discarding the glass sheet to obtain the graphene film sensor.

[0023] The present invention also provides a glucose sensor, which comprises the graphene film sensor as described above.

[0024] The present invention also provides a method for preparing a glucose sensor, comprising the following steps:

[0025] S1, preparing a Prussian blue solution and a chitosan solution immobilized with glucose oxidase;

[0026] S2, placing the graphene film sensor as described above in a Prussian blue solution for electroplating, and drying after the electroplating is completed;

[0027] S3, dropping the chitosan solution with glucose oxidase fixed thereon onto the graphene film sensor dried in step S2, and letting it stand to obtain the glucose sensor.

[0028] Preferably, in step S1, the Prussian blue solution comprises 0.01 M HCl, 2.5×10 -3 M FeCl3, 2.5X10 -3 M of K3[Fe(CN)6] and 0.1M KCl.

[0029] Preferably, in step S1, the chitosan solution immobilized with glucose oxidase is prepared by mixing a chitosan solution with a mass fraction of 2% and a glucose oxidase with a concentration of 34 mg / ml in a volume ratio of 1:1.

[0030] Preferably, the preparation method of the chitosan solution with a mass fraction of 2% is: dissolving chitosan in acetic acid solution according to a weight ratio, stirring until the chitosan is fully dissolved, and placing at room temperature until it becomes clear without bubbles to obtain a chitosan solution with a mass fraction of 2%.

[0031] Preferably, the step S2 specifically comprises: connecting the graphene film sensor to the working electrode of the electrochemical workstation, placing the graphene film sensor in a Prussian blue solution, electroplating for 60 seconds using a constant voltage of 0.4 V, and then drying at room temperature.

[0032] Preferably, the step S3 specifically comprises: adding the chitosan solution immobilized with glucose oxidase dropwise onto the graphene film sensor dried in step S2, wherein the amount of chitosan solution immobilized with glucose oxidase added is sufficient to form a non-flowing water drop shape on the graphene film sensor; and then placing it at room temperature for 5-6 hours to obtain the glucose sensor.

[0033] The beneficial effects of the present invention are:

[0034] The present invention provides a graphene film sensor and a glucose sensor based on the graphene film sensor. In the present invention, carbon dioxide laser cutting is used to form dense and porous graphene to prepare a graphene film sensor and further prepare a thin-film glucose sensor, which can realize non-invasive detection of blood sugar. In the present invention, the thin-film sensor obtained by the laser cutting method has low requirements on the sensor processing environment, high processing speed and low processing cost, which can meet the requirements of time-saving and cost-saving for large-scale processing. At the same time, laser cutting is simple to operate and the operation process is easy to control. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 The performance test results of the graphene film sensor of Example 1 are as follows;

[0036] Figure 2 These are the performance test results of the glucose sensor of Example 2. DETAILED DESCRIPTION

[0037] The present invention is further described in detail below in conjunction with embodiments so that those skilled in the art can implement the invention with reference to the description.

[0038] It should be understood that the terms such as “having”, “including” and “comprising” used herein do not exclude the existence or addition of one or more other elements or combinations thereof.

[0039] Example 1

[0040] This embodiment provides a graphene film sensor, which is prepared by the following method:

[0041] 1) Processing material preparation:

[0042] 1.1) Take a 10cm×10cm glass slide, wash it with deionized water, and stick double-sided tape on one side of the glass slide;

[0043] 1.2) Stick the non-adhesive side of the water-soluble adhesive tape on the double-sided adhesive tape of the glass sheet until the double-sided adhesive tape is fully applied;

[0044] 1.3) Tear off the protective layer on the surface of the hydrosol tape to expose the sticky surface;

[0045] 1.4) Cut a PI film with a thickness of 0.15 mm into the same size as the glass sheet, and then attach it to the sticky surface of the water-soluble adhesive tape. Ensure that there are no bubbles between the PI film and the water-soluble adhesive tape during attachment to obtain a processed material.

[0046] 2) Electrode processing:

[0047] 2.1) Draw the required electrode pattern in the CAD software, import the electrode pattern into the CO2 laser cutting machine, set the processing parameters: power 5%, speed 7%, PPI1000, and process in the form of raster;

[0048] 2.2) processing the processed material obtained in step 1) by a carbon dioxide laser cutting machine according to the electrode pattern to obtain a primary product;

[0049] 2.3) The initial product is placed in water to dissolve the water-soluble adhesive tape between the PI film and the glass sheet in the initial product, and then the PI film is separated from the glass sheet and the glass sheet is discarded to obtain a porous graphene film sensor.

[0050] The graphene film sensor was tested for its redox performance in PB solution at -0.05V-0.4V (VSAg / AgCl electrode) and a scan rate of 50mv / s; Figure 1 , which is the performance test result of the graphene film sensor of Example 1. From the test results, it can be seen that the interval ΔEp between the oxidation peak and the reduction peak of the graphene film electrode is less than 50mv, and it has strong redox properties.

[0051] Example 2

[0052] This embodiment provides a glucose sensor, which includes the graphene film sensor of embodiment 1. The preparation method of the glucose sensor includes the following steps:

[0053] S1, preparing a Prussian blue solution, a chitosan solution, and a chitosan solution immobilized with glucose oxidase;

[0054] The Prussian blue solution includes 0.01M HCl, 2.5X10 -3 M FeCl3, 2.5X10 -3 M of K3[Fe(CN)6] and 0.1M KCl.

[0055] The preparation method of the chitosan solution with a mass fraction of 2% is as follows: dissolve chitosan in acetic acid solution according to the weight ratio, stir until the chitosan is fully dissolved, and place it at room temperature until it is clear without bubbles to obtain a chitosan solution with a mass fraction of 2%.

[0056] The chitosan solution immobilized with glucose oxidase is prepared by mixing a chitosan solution with a mass fraction of 2% and a glucose oxidase with a concentration of 34 mg / ml in a volume ratio of 1:1.

[0057] S2. Connect the graphene film sensor of Example 1 to the working electrode of the electrochemical workstation, use Ag / AgCl as the reference electrode, place the graphene film sensor in a Prussian blue solution, electroplate at a constant voltage of 0.4 V for 60 seconds, and then dry at room temperature.

[0058] S3, adding the chitosan solution immobilized with glucose oxidase dropwise onto the graphene film sensor dried in step S2, wherein the amount of chitosan solution immobilized with glucose oxidase added is sufficient to form a non-flowing water droplet shape on the graphene film sensor; and then placing at room temperature for 5-6 hours to obtain the glucose sensor.

[0059] The detection principle of the glucose sensor is as follows: hydrogen peroxide is generated under the action of glucose oxidase, and hydrogen peroxide undergoes a catalytic reaction with the Prussian blue film to generate water and free electrons. The reaction current is measured to obtain the glucose concentration.

[0060] Among them, the porous graphene sensor facilitates the electroplating of Prussian blue.

[0061] In a preferred embodiment, CV is scanned before and after electroplating. Scanning before electroplating can detect whether the characteristics of the manufactured electrode meet the electroplating requirements. Scanning after electroplating can stabilize the Prussian blue layer.

[0062] In a preferred embodiment, when the processed electrode is connected to an electrochemical workstation, a Pt electrode clamp can be used to clamp the working electrode of the electrode, and the Pt electrode sheet can be used as a counter electrode.

[0063] Reference Figure 2 , is the performance test result of the glucose sensor of Example 2, which is an IT test in an electrochemical workstation, and the initial potential is set to 0.172 V according to the oxidation peak potential of 0.172 V. 0.017 mM of glucose is added every 100 seconds. It can be seen from the IT test graph that the glucose sensor has an obvious response to glucose.

[0064] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the implementation modes. They can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to specific details.

Claims

1. A glucose sensor, characterized in that: It includes a graphene film sensor; The graphene film sensor is prepared by the following method: 1) Processing material preparation: 1.1) Take a glass slide, clean it, and stick double-sided tape on one side of the glass slide; 1.2) Stick the non-adhesive side of the water-soluble adhesive tape on the double-sided adhesive tape of the glass sheet until the double-sided adhesive tape is fully applied; 1.3) Tear off the protective layer on the surface of the hydrosol tape to expose the sticky surface; 1.4) Cutting the PI film into the same size as the glass sheet, and then attaching it to the sticky surface of the water-soluble adhesive tape to obtain a processed material; 2) Electrode processing: 2.1) Draw the required electrode pattern and import the electrode pattern into the CO2 laser cutting machine; 2.2) According to the electrode pattern, the processed material obtained in step 1) is processed by a carbon dioxide laser cutting machine to obtain a primary product; 2.3) placing the initial product in water to dissolve the water-soluble adhesive tape between the PI film and the glass sheet in the initial product, and then separating the PI film from the glass sheet and discarding the glass sheet to obtain the graphene film sensor; The preparation method of the glucose sensor comprises the following steps: S1, preparing a Prussian blue solution and a chitosan solution immobilized with glucose oxidase; S2, placing the graphene film sensor in a Prussian blue solution for electroplating, and drying after the electroplating is completed; S3, dropping the chitosan solution immobilized with glucose oxidase onto the graphene film sensor dried in step S2, and letting it stand to obtain the glucose sensor; In step S1, the chitosan solution immobilized with glucose oxidase is prepared by mixing a chitosan solution with a mass fraction of 2% and a glucose oxidase with a concentration of 34 mg / ml in a volume ratio of 1:1; The step S3 specifically comprises: adding the chitosan solution with fixed glucose oxidase to the graphene film sensor dried in step S2, wherein the amount of chitosan solution with fixed glucose oxidase added is sufficient to form a non-flowing water drop shape on the graphene film sensor; and then placing it at room temperature for 5-6 hours to obtain the glucose sensor.

2. The glucose sensor according to claim 1, characterized in that The step 1) specifically includes: 1.1) Take a glass slide, wash it with deionized water, and stick double-sided tape on one side of the glass slide; 1.2) Stick the non-adhesive side of the water-soluble adhesive tape on the double-sided adhesive tape of the glass sheet until the double-sided adhesive tape is fully applied; 1.3) Tear off the protective layer on the surface of the hydrosol tape to expose the sticky surface; 1.4) Cut a PI film with a thickness of 0.05-0.5 mm into the same size as the glass sheet, and then attach it to the sticky surface of the water-soluble adhesive tape. Ensure that there are no bubbles between the PI film and the water-soluble adhesive tape during attachment to obtain a processed material.

3. The glucose sensor according to claim 2, characterized in that The step 2) specifically includes: 2.1) Draw the required electrode pattern in the CAD software, import the electrode pattern into the CO2 laser cutting machine, set the processing parameters: power 5%, speed 7%, PPI1000, and process in the form of raster; 2.2) According to the electrode pattern, the processed material obtained in step 1) is processed by a carbon dioxide laser cutting machine to obtain a primary product; 2.3) placing the initial product in water to dissolve the water-soluble adhesive tape between the PI film and the glass sheet in the initial product, and then separating the PI film from the glass sheet and discarding the glass sheet to obtain the graphene film sensor.

4. The glucose sensor according to claim 3, characterized in that In step S1, the Prussian blue solution includes 0.01M HCl, 2.5X10 -3 M FeCl3, 2.5X10 -3 M of K3[Fe(CN)6] and 0.1M KCl.

5. The glucose sensor according to claim 4, characterized in that in, The preparation method of the chitosan solution with a mass fraction of 2% is as follows: dissolve chitosan in acetic acid solution according to the weight ratio, stir until the chitosan is fully dissolved, and place it at room temperature until it is clear without bubbles, so as to obtain a chitosan solution with a mass fraction of 2%.

6. The glucose sensor according to claim 3, characterized in that: The step S2 specifically includes: connecting the graphene film sensor to the working electrode of the electrochemical workstation, placing the graphene film sensor in a Prussian blue solution, electroplating for 60 seconds using a constant voltage of 0.4V, and then drying at room temperature.

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