Preparation method and application of a dual-network photonic crystal hydrogel for visualizing blood glucose detection

Abstract

The application discloses a preparation method of a double-network photonic crystal hydrogel for visualizing blood glucose detection and application thereof, and belongs to the biomedical field.The preparation method of the double-network photonic crystal hydrogel comprises the following steps: injecting a glucose-unresponsive hydrogel solution into a gap of a photonic crystal and solidifying, and then removing a microsphere template of the photonic crystal by chemical etching to obtain a hydrogel with inverse opal structure and structural color; and filling a glucose-responsive hydrogel solution into the gap of the hydrogel as a skeleton and solidifying to obtain a double-network photonic crystal hydrogel with structural color and glucose responsiveness.The double-network photonic crystal hydrogel has good biocompatibility and glucose reversible responsiveness, can visualize the glucose concentration, and can be used for visualizing detection of blood glucose level.

Description

Technical Field

[0001] This invention belongs to the field of biomedicine, specifically relating to a method for preparing a dual-network photonic crystal hydrogel for visual blood glucose detection and its application. Background Technology

[0002] Diabetes mellitus is a global chronic disease that seriously threatens human health, characterized primarily by high blood sugar levels. Long-term diabetes patients experience chronic damage and functional impairment in various tissues, particularly the eyes, kidneys, heart, blood vessels, and nerves. Currently, over 537 million people worldwide have been diagnosed with type 1 or type 2 diabetes, and this number continues to rise. High glucose levels are the most important biochemical indicator for diabetic patients; therefore, blood glucose monitoring is crucial for diagnosis and daily health management. Currently, finger-prick blood glucose meters are the most common method. However, frequent blood tests consume large quantities of test strips, increasing the financial burden on patients. Furthermore, this invasive method causes pain, significantly reducing patient dependence and posing a risk of infection. Therefore, compared to current expensive and painful methods, developing a low-cost, simple, non-invasive, and minimally painful glucose monitoring method has significant clinical practical value. Summary of the Invention

[0003] The purpose of this invention is to provide a method for preparing a dual-network photonic crystal hydrogel for visual blood glucose detection and its application. The dual-network photonic crystal hydrogel of this invention enables visualized, reversible, and reusable detection of glucose levels in body fluids.

[0004] The objective of this invention is achieved through the following technical solution:

[0005] A method for preparing a dual-network photonic crystal hydrogel for visual blood glucose detection includes the following steps: injecting a glucose-non-responsive hydrogel solution into the gaps of a photonic crystal and solidifying it; then removing the microsphere template of the photonic crystal using chemical etching to obtain a hydrogel with an inverse opal structure and structural color; using this as a framework; filling the vacancies with a glucose-responsive hydrogel solution and solidifying it to obtain a dual-network photonic crystal hydrogel with structural color and glucose responsiveness, i.e., the dual-network photonic crystal hydrogel for visual blood glucose detection. The photonic crystal is preferably a silica photonic crystal, and preferably etched using hydrofluoric acid.

[0006] In some embodiments, the glucose-free hydrogel solution is a P(AA-Am) hydrogel solution, which is initiated and cured using a thermal initiator. It preferably contains the following components in the following amounts: 10%-25% (v / v) acrylic monomer, 10%-25% (w / v) acrylamide monomer, 1‰-5‰ (w / v) potassium persulfate, 1‰-5‰ (w / v) N-N'-methylenebisacrylamide, with water as the solvent. More preferably, it contains the following components in the following amounts: 20% (v / v) acrylic monomer, 10% (w / v) acrylamide monomer, 5‰ (w / v) potassium persulfate, 3‰ (w / v) N-N'-methylenebisacrylamide, with water as the solvent.

[0007] In some embodiments, the glucose-responsive hydrogel solution is a hydrogel solution containing a glucose-responsive molecule, preferably 4-(2-acrylamidoethylcarbamoyl)-3-fluorophenylboronic acid (AFPBA). Further, the glucose-responsive hydrogel solution is a P(AA-Am) hydrogel solution containing AFPBA, cured using a photoinitiator, preferably comprising the following components in the following proportions: 10%-25% (v / v) acrylic monomer, 10%-25% (w / v) acrylamide monomer, 5%-20% (w / v) AFPBA, 1%-5% (w / v) 2-hydroxy-2-methyl-1-phenyl-1-propanone, 1‰-5‰ (w / v) N-N'-methylenebisacrylamide, with water as the solvent. More preferably, it comprises the following components in the following amounts: 20% (v / v) acrylic monomer, 10% (w / v) acrylamide monomer, 10% (w / v) AFPBA, 1% (w / v) 2-hydroxy-2-methyl-1-phenyl-1-propanone, 3‰ (w / v) N-N'-methylenebisacrylamide, and water as the solvent.

[0008] Furthermore, the preparation method of the dual-network photonic crystal hydrogel for visual blood glucose detection includes the following steps:

[0009] (1) The photonic crystal prepared using an aqueous dispersion of silica microspheres is fixed between two glass slides.

[0010] (2) Inject the glucose-insensitive hydrogel solution into the gaps of the silica photonic crystal, heat and solidify it, and then remove the hydrogel and the photonic crystal.

[0011] (3) The removed hydrogel and photonic crystal were soaked together in hydrofluoric acid solution to etch the silica microspheres, resulting in a hydrogel with an inverse opal structure and structural color.

[0012] (4) The hydrogel with inverse opal structure and structural color is immersed in a hydrogel solution with glucose responsive function and cured by ultraviolet light (preferably 331nm) to obtain the dual-network photonic crystal hydrogel for visual blood glucose detection.

[0013] In step (1), the photonic crystal is preferably prepared using a self-assembled horizontal deposition method, specifically including the following steps: preparing a PDMS fence using PDMS monomer and a crosslinking agent, and treating it with O2 plasma to obtain a hydrophilic PDMS fence. The hydrophilic PDMS fence is then bonded to a clean glass slide, and an aqueous dispersion of SiO2 microspheres is added to the fence. After the water evaporates, the photonic crystal is obtained. The water evaporation is preferably carried out at 35-40 degrees Celsius (preferably 37 degrees Celsius).

[0014] In step (2), the heating temperature is 50-70 degrees Celsius, preferably 60 degrees Celsius.

[0015] In step (3), the concentration of the hydrofluoric acid solution is 10%-49% (wt.), preferably 49% (wt.).

[0016] In the preparation method of the dual-network photonic crystal hydrogel for visual blood glucose detection, the structural color of the dual-network photonic crystal hydrogel can be controlled by adjusting the particle size of the silica microspheres.

[0017] A dual-network photonic crystal hydrogel for visual blood glucose detection is obtained by the above preparation method.

[0018] A schematic diagram of the structure of the dual-network photonic crystal hydrogel of the present invention is shown below. Figure 1 The hydrogel system serving as the framework is an acrylamide co-acrylic acid hydrogel, which is initiated and cured using a thermal initiator, exhibiting good biocompatibility and reversibility. The glucose-responsive hydrogel system serving as the filler is an acrylamide co-acrylic acid hydrogel system with added glucose-responsive molecule AFPBA, which is initiated and cured using a photoinitiator. The resulting hydrogel exhibits good biocompatibility, glucose responsiveness, and good reversibility.

[0019] The visualization function of the dual-network photonic crystal hydrogel of this invention is achieved through the structural color characteristics of photonic crystals. The periodic structure inside the photonic crystal prevents light of certain wavelengths from propagating and thus reflects it. The color of the photonic crystal changes with the changes in the periodic structure. Due to the structural color characteristic of photonic crystals, when the photonic crystal hydrogel swells, its color undergoes a visible change.

[0020] The glucose-responsive molecule AFPBA in the dual-network photonic crystal hydrogel of this invention, as a derivative of phenylboronic acid, exhibits excellent glucose responsiveness. When the dual-network photonic crystal hydrogel dissolves in a glucose solution, the boric acid group on the phenyl ring of AFPBA partially ionizes, becoming negatively charged. This boric acid then binds to the dihydroxyl group in the glucose molecule. Therefore, as the glucose concentration increases, the ionization equilibrium shifts in the ionization direction, causing more hydrophobic, uncharged PBA to ionize into hydrophilic, negatively charged PBA. This results in swelling of the entire hydrogel network, causing a red shift in the sample color, demonstrating its excellent glucose responsiveness. Conversely, as the glucose concentration decreases, the ionization equilibrium of AFPBA reverses, causing the hydrogel sample volume to shrink and a blue shift in the sample color, thus achieving the purpose of visually reading out glucose levels.

[0021] The application of the dual-network photonic crystal hydrogel for visualizing blood glucose detection in blood glucose detection or in the preparation of blood glucose detection products.

[0022] A blood glucose testing product comprising the aforementioned dual-network photonic crystal hydrogel for visual blood glucose detection.

[0023] The blood glucose test described is a visual test of blood glucose levels.

[0024] Advantages and beneficial effects of this invention: This invention utilizes the ionization equilibrium of glucose-responsive molecules to achieve visualized glucose level detection. The resulting dual-network photonic crystal hydrogel sample exhibits vibrant structural color and good reversibility. Furthermore, the structural color of the dual-network photonic crystal hydrogel can be controlled by adjusting the particle size of the photonic crystals. Compared to single-network photonic crystal hydrogels, the dual-network photonic crystal hydrogel in this invention has a larger volume ratio of responsive hydrogel, resulting in a faster response to glucose and potentially halving the reaction time. Attached Figure Description

[0025] Figure 1 This is a two-dimensional schematic diagram of the dual-network photonic crystal hydrogel of the present invention.

[0026] Figure 2 These are morphology images of photonic crystals prepared using SiO2 microspheres of different particle sizes. From left to right, the red, green, and blue photonic crystals use SiO2 microspheres with particle sizes of 300 nm, 270 nm, and 240 nm, respectively.

[0027] Figure 3 This is a diagram of hue values.

[0028] Figure 4These are schematic diagrams of the dual-network photonic crystal hydrogel and the single-network photonic crystal hydrogel of the present invention: (a) single-network photonic crystal hydrogel; (b) dual-network photonic crystal hydrogel.

[0029] Figure 5 The reversible responsiveness change of the blue dual-network photonic crystal hydrogel in glucose solution is shown in the figures: (a) the color of the blue dual-network photonic crystal hydrogel, and (b) the hue value of the blue dual-network photonic crystal hydrogel.

[0030] Figure 6 The reversible responsiveness change of the green dual-network photonic crystal hydrogel in glucose solution is shown in the figures: (a) the color of the green dual-network photonic crystal hydrogel, and (b) the hue value of the green dual-network photonic crystal hydrogel.

[0031] Figure 7 It shows the hue value change of a blue dual-network photonic crystal hydrogel after cyclic immersion in a glucose solution.

[0032] Figure 8 This is a comparison of the responsiveness of dual-network photonic crystal hydrogels and single-network photonic crystal hydrogels in glucose solution.

[0033] Figure 9 This is an in vivo glucose responsiveness test of a green dual-network photonic crystal hydrogel. (a) Mouse wound model, (b) Color changes of the hydrogel corresponding to mouse wounds with different blood glucose levels, (c) Color value changes of the hydrogel corresponding to mouse wounds with different blood glucose levels. Detailed Implementation

[0034] The following embodiments are used to further illustrate the present invention, but should not be construed as limiting the present invention. Unless otherwise specified, the technical means used in the embodiments are conventional means well known to those skilled in the art.

[0035] Example 1: Preparation and Performance Testing of Photonic Crystal Hydrogels

[0036] 1. Preparation of photonic crystals

[0037] SiO2 microsphere dispersions were prepared using ammonia, deionized water, ethanol, and tetraethyl orthosilicate. The SiO2 microspheres were then purified and freeze-dried to obtain SiO2 microsphere solid powders with different particle sizes (220-320 nm).

[0038] PDMS prepolymer and curing agent were mixed at a mass ratio of 10:1 and crosslinked to prepare PDMS fences of different shapes with a depth of 2 mm. The PDMS fences were then treated with O2 plasma to increase their hydrophilicity.

[0039] The PDMS hydrophilic fence and a clean glass slide are bonded together and placed on a horizontal heating stage at 35-40 degrees Celsius (preferably 37 degrees Celsius), and an aqueous dispersion of SiO2 microspheres is added. As the water evaporates during heating, the SiO2 microspheres gradually accumulate in the center of the PDMS fence to form a close-packed structure of a photonic crystal. This process is rapid and can be completed in only 3-4 hours.

[0040] By controlling the concentration of reactants, SiO2 microspheres of different sizes were obtained, thereby producing photonic crystals with different colors. Figure 2 The structural color of a color can be represented by its corresponding hue value. Hue, or color appearance, is one of the three elements of color and its primary characteristic; it is the most accurate standard for distinguishing different colors. Hue values ​​can be represented using a color wheel (…). Figure 3 Hue values ​​are represented in degrees from 0 to 360, for example, 0° is red, 120° is green, and 240° is blue. If a color changes counterclockwise and exceeds 0°, the hue value can be represented by a negative number; for example, 300° and -60° both correspond to the same color. Conversely, if a color changes clockwise and exceeds 0°, it can be represented by a hue value plus 360°; for example, 60° and 420° both correspond to the same color.

[0041] 2. Preparation of single-network photonic crystal hydrogels

[0042] Weigh out 20% (v / v) acrylic monomer, 10% (w / v) acrylamide monomer, 5‰ (w / v) potassium persulfate, 3‰ (w / v) N-N'-methylenebisacrylamide, and 10% (w / v) AFPBA respectively, add them to water, and shake thoroughly to dissolve them, thus obtaining a hydrogel solution.

[0043] The photonic crystal was fixed between two glass slides. A hydrogel solution was injected into the gap between the photonic crystal and the slides, and the mixture was heated at 60°C for one hour. After curing, the hydrogel and photonic crystal samples were removed together and immersed in a 49% (wt.) hydrofluoric acid solution for 24 hours. The silica microspheres were then etched, removed, and washed with pure water, ultimately yielding a single-network photonic crystal hydrogel sample with distinct structural colors. Its two-dimensional structure is shown in the schematic diagram below. Figure 4 As shown in a.

[0044] 3. Preparation of dual-network photonic crystal hydrogels

[0045] (1) Preparation of skeleton acrylamide coacrylic acid hydrogel

[0046] Weigh out 20% (v / v) acrylic monomer, 10% (w / v) acrylamide monomer, 5‰ (w / v) potassium persulfate, and 3‰ (w / v) N-N'-methylenebisacrylamide respectively, add them to water, and shake thoroughly to dissolve them, thus obtaining a hydrogel solution.

[0047] The photonic crystal was fixed between two glass slides. The hydrogel solution was injected into the gap between the photonic crystal and the two glass slides. After heat curing at 60 degrees Celsius for one hour, the hydrogel and photonic crystal samples were removed together, immersed in 49% (wt.) hydrofluoric acid solution for 24 hours, and then taken out and rinsed with pure water.

[0048] (2) Preparation of dual-network photonic crystal hydrogels

[0049] The above acrylamide coacrylic acid hydrogel was immersed in a hydrogel solution containing AFPBA for five minutes, then removed and subjected to 365nm ultraviolet light (light intensity density 68.24mW / cm²). 2 Irradiation for 3 minutes followed by photocuring yielded a dual-network photonic crystal hydrogel sample with distinct structural colors, as shown in the schematic diagram of its two-dimensional structure. Figure 4 As shown in b. The parameters of the hydrogel solution containing AFPBA are: 20% (v / v) acrylic monomer, 10% (w / v) acrylamide monomer, 10% (w / v) AFPBA, 1% (w / v) 2-hydroxy-2-methyl-1-phenyl-1-propanone, 3‰ (w / v) N-N'-methylenebisacrylamide, and water as the solvent.

[0050] 4. In vitro glucose response and reversibility test of dual-network photonic crystal hydrogel

[0051] The dual-network photonic crystal hydrogels were individually immersed in glucose solutions of concentrations of 0 mM, 6.6 mM, 13.2 mM, 19.8 mM, and 26.4 mM, respectively. After 15 minutes of immersion, the hydrogels were removed, and their color changes were observed and recorded. To verify the reversibility of the photonic crystal hydrogels' response to glucose, the hydrogels were then individually immersed in glucose solutions of decreasing concentrations, again for 15 minutes. After immersion, the hydrogels were removed, and their color changes were observed and recorded.

[0052] (1) Blue structural color photonic crystals and dual-network photonic crystal hydrogels were prepared using silica microspheres with a particle size of 240 nm. The blue structural color dual-network photonic crystal hydrogel was used for testing. The reversible responsiveness of the hydrogel samples to glucose solutions of different concentrations is shown in the figure below. Figure 5 As shown.

[0053] Depend on Figure 5 As can be seen, the blue hydrogel exhibits a red shift in color after being immersed in glucose solutions of varying concentrations for a sufficient period of time. Figure 5 a) This is because the interaction between AFPBA and glucose causes the entire hydrogel to swell, leading to a change in the internal periodic structure of the photonic crystal. According to the Bragg diffraction formula, the position of the reflection peak redshifts. Software was used to collect and analyze the hue changes of the obtained image pixels, and the results are as follows: Figure 5 As shown in b, the hue value of the macroscopic structural color on the surface of the blue photonic crystal hydrogel gradually changes from 173° corresponding to 0 mM glucose solution to 62° corresponding to 26.4 mM glucose solution, as illustrated in the hue value diagram (). Figure 3 This indicates that the color has undergone a redshift, with a hue value change of 111°, thus proving the glucose visualization detection capability of the photonic crystal hydrogel.

[0054] The above photonic crystal hydrogel was immersed in a high-concentration glucose solution, then back to a low-concentration glucose solution, and finally immersed in pure water. The macroscopic color of the photonic crystal hydrogel changed from green back to blue. Figure 5 a) The color undergoes a blue shift, and its hue value and data reversibly match the data obtained when soaking in glucose solutions of varying concentrations from low to high. Figure 5 b) This verifies that the hydrogel has good reversible responsiveness to glucose.

[0055] (2) Similarly, green structural color photonic crystals and dual-network photonic crystal hydrogels were prepared using silica microspheres with a particle size of 270 nm. Experiments were conducted using the green structural color dual-network photonic crystal hydrogel. The reversible responsiveness of the hydrogel samples to glucose solutions of different concentrations is shown in the figures below. Figure 6 As shown.

[0056] Depend on Figure 6 As can be seen, the green structural color photonic crystal hydrogel also exhibited a redshift phenomenon after being immersed in glucose solutions of varying concentrations for a sufficient period of time. Figure 6 a) Its reaction principle is similar to that of the aforementioned blue photonic crystal hydrogel. Furthermore, hue value analysis was performed on the obtained image results, and the results are as follows: Figure 6 As shown in b, the hue value of the macroscopic structural color on the surface of the green photonic crystal hydrogel gradually changes from 160° (corresponding to 0 mM glucose solution) to -70° (corresponding to 26.4 mM glucose solution). Figure 6 b) The color underwent a red shift, with a hue value change of 230°, further demonstrating the glucose visualization detection capability of the photonic crystal hydrogel.

[0057] Furthermore, when the above photonic crystal hydrogel was immersed in a high-concentration glucose solution and then back to a low-concentration glucose solution, and finally immersed in pure water, the macroscopic color of the photonic crystal hydrogel changed from red back to green. Figure 6a) The color undergoes a blue shift, and its hue value data reversibly matches the data obtained from immersion in glucose concentrations from low to high. Figure 6 b) further verified that the hydrogel has good reversible responsiveness to glucose.

[0058] In the above experiment, when reacting in glucose solutions of varying concentrations from low to high, the hue value of the green photonic crystal hydrogel varied over a range of 230 degrees, which was greater than that of the blue photonic crystal hydrogel over a range of 111 degrees, making it more conducive to visualization, reading out, and testing.

[0059] 5. Repeatability testing of the reversible response of dual-network photonic crystal hydrogels

[0060] Taking a blue structural color photonic crystal hydrogel as an example, it was repeatedly immersed in glucose solutions with concentrations of 0 mM, 6.6 mM, 13.2 mM, 19.8 mM, and 26.4 mM to verify the repeatability and stability of its glucose responsiveness. The hue values ​​of the photonic crystal hydrogel were recorded during the process, and the results are as follows: Figure 7 As shown, during each immersion cycle, the macroscopic structural color of the photonic crystal hydrogel surface gradually decreased from 173° to 62°, and then increased back to 173°; and after 8 cycles, the hue value remained essentially stable. These results indicate that the reversible response of the hydrogel is stable, and the hydrogel can be reused for real-time monitoring of glucose concentration changes.

[0061] 6. Comparison of responsiveness between dual-network photonic crystal hydrogels and single-network photonic crystal hydrogels

[0062] To compare the response times of single-network and dual-network photonic crystal hydrogels, different photonic crystal hydrogels were prepared and their response times were tested, specifically including:

[0063] Blue structural color photonic crystals and single-network photonic crystal hydrogels were prepared using silica microspheres with a particle size of 240 nm. The single-network photonic crystal hydrogels were then immersed in a 26.4 mM glucose solution, and the color change over time was observed.

[0064] Blue structural color photonic crystals and dual-network photonic crystal hydrogels were prepared using silica microspheres with a particle size of 240 nm. The dual-network photonic crystal hydrogels were then immersed in a 26.4 mM glucose solution, and the color change over time was observed.

[0065] like Figure 8As shown, the dual-network photonic crystal hydrogel completed the reaction after 15 minutes of immersion, after which its hue value stabilized and remained unchanged. In contrast, the single-network photonic crystal hydrogel required 30 minutes to complete the reaction, after which its hue value also remained unchanged. This is because, in the dual-network photonic crystal hydrogel, the glucose-responsive hydrogel occupies a larger volume proportion (…). Figure 4 Therefore, it has a faster response than single-network photonic crystal hydrogels.

[0066] Example 2: In vivo glucose responsiveness test of dual-network photonic crystal hydrogel

[0067] A diabetic mouse model was established using C57 black mice and streptozotocin to induce different in vivo blood glucose levels (8.3 mM, 16.4 mM, and 25.7 mM). Hair was removed from the backs of the mice, and 5 mm diameter wounds were created by punching holes in their backs. Green structurally colored photonic crystals and dual-network photonic crystal hydrogels were prepared using 270 nm silica microspheres. The structurally colored side of the prepared green structurally colored dual-network photonic crystal hydrogel was applied to the wound surface and fixed with a transparent dressing. After 15 minutes, the dressing was removed, and the color change of the photonic crystal hydrogel was observed and recorded.

[0068] Mouse wound model experiments, such as Figure 9 As shown in Figure a. The results obtained from the experiment using green photonic crystal hydrogel are as follows. Figure 9 As shown in b, a significant redshift was observed in the green photonic crystal, verifying the responsiveness of the photonic crystal hydrogel on organisms. In mouse wounds with a blood glucose level of 8.3 mM, the hue value of the photonic crystal hydrogel was 147°. When the blood glucose level in the mice increased to 25.7 mM, the hue value of the photonic crystal hydrogel gradually decreased to 107°. Figure 9 c) The hue value changed by 40°, which verified the responsiveness of the photonic crystal hydrogel on organisms.

[0069] It should be noted that small animals have less exudate on their skin surface, so the amount of liquid involved in the reaction is not as sufficient as in a glucose solution. Therefore, the effect of blood glucose detection in in vivo experiments is not as obvious as the detection effect in a glucose solution.

[0070] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A method for preparing a dual-network photonic crystal hydrogel for visual blood glucose detection, characterized in that: The process includes the following steps: injecting a glucose-insensitive hydrogel solution into the gaps of a silica photonic crystal and curing it; then using hydrofluoric acid to etch away the microsphere template of the photonic crystal to obtain a hydrogel with an inverse opal structure and structural color; using this hydrogel as a framework to fill the vacancies with a glucose-responsive hydrogel solution and curing it to obtain the dual-network photonic crystal hydrogel for visual blood glucose detection. The glucose-free hydrogel solution comprises the following components in the following amounts: 10%-25% (v / v) acrylic monomer, 10%-25% (w / v) acrylamide monomer, 1‰-5‰ (w / v) potassium persulfate, 1‰-5‰ (w / v) N-N'-methylenebisacrylamide, and water as the solvent; The glucose-responsive hydrogel solution contains the following components in the following proportions: 10%-25% (v / v) acrylic monomer, 10%-25% (w / v) acrylamide monomer, 5%-20% (w / v) 4-(2-acrylamidoethylcarbamoyl)-3-fluorophenylboronic acid, 1%-5% (w / v) 2-hydroxy-2-methyl-1-phenyl-1-propanone, 1‰-5‰ (w / v) N-N'-methylenebisacrylamide, and water as the solvent.

2. The method for preparing the dual-network photonic crystal hydrogel for visual blood glucose detection according to claim 1, characterized in that: The glucose-free hydrogel solution comprises the following components in the following amounts: 20% (v / v) acrylic monomer, 10% (w / v) acrylamide monomer, 5‰ (w / v) potassium persulfate, 3‰ (w / v) N-N'-methylenebisacrylamide, and water as the solvent.

3. The method for preparing the dual-network photonic crystal hydrogel for visual blood glucose detection according to claim 1, characterized in that: The glucose-responsive hydrogel solution contains the following components in the following proportions: 20% (v / v) acrylic monomer, 10% (w / v) acrylamide monomer, 10% (w / v) 4-(2-acrylamidoethylcarbamoyl)-3-fluorophenylboronic acid, 1% (w / v) 2-hydroxy-2-methyl-1-phenyl-1-propanone, 3‰ (w / v) N-N'-methylenebisacrylamide, and water as the solvent.

4. The method for preparing the dual-network photonic crystal hydrogel for visual blood glucose detection according to claim 1, characterized in that: The concentration of hydrofluoric acid used for etching is 10 wt%-49 wt%.

5. A dual-network photonic crystal hydrogel for visual blood glucose detection, characterized in that: It is obtained by the preparation method according to any one of claims 1-4.

6. The application of the dual-network photonic crystal hydrogel according to claim 5 in the preparation of blood glucose detection products.

7. A blood glucose testing product, characterized in that: It includes the dual-network photonic crystal hydrogel of claim 5.

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