A porous hydrogel film for detecting sweat glucose and preparation and detection method thereof

Abstract

The present application relates to a kind of detection of sweat glucose porous hydrogel film and preparation, detection method, porous hydrogel film includes: carrier, cobalt oxyhydroxide modified rare earth nanoparticles and glucose oxidase;The cobalt oxyhydroxide modified rare earth nanoparticles and the glucose oxidase are distributed in the inside of the carrier;The cobalt oxyhydroxide is coated on the surface of the rare earth nanoparticles to form the cobalt oxyhydroxide modified rare earth nanoparticles;The cobalt oxyhydroxide is used to quench the fluorescence emission of the rare earth nanoparticles;The carrier is formed by polyacrylamide intercrossing.This application detects glucose in sweat by the principle of fluorescence resonance energy transfer, with the advantages of high efficiency and stability, safe and simple to use, the structure of porous hydrogel film is simple, easy to make and low in cost, the detection of sweat glucose is realized by observing the fluorescence intensity of film, and it can also work in dark environment.

Description

Technical Field

[0001] This invention belongs to the field of sweat glucose detection technology, specifically relating to a porous hydrogel membrane for detecting sweat glucose and its preparation and detection methods. Background Technology

[0002] Human sweat contains various ions, organic molecules, amino acids, hormones, proteins, and other secretions, all closely related to the body's physiological state. Monitoring sweat composition allows for analysis of electrolyte imbalances, lactate levels, sweat glucose levels, dehydration status, potential diseases, and calorie consumption, thereby monitoring vital signs. Compared to other bodily fluids, especially blood, sweat testing can be performed externally, making it a non-invasive and convenient method. Sweat testing demonstrates unique advantages in the field of wearable sensors, particularly in health tracking and monitoring during human movement. Sweat sensors provide continuous and real-time physiological information by dynamically and non-invasively measuring biomarkers in bodily fluids, while direct contact with the sampled fluid does not cause discomfort to the wearer.

[0003] The sensitive materials, structural design, hardware systems, and software platforms of sweat sensors have been studied by numerous teams worldwide. Various strategies, including electrochemical detection, colorimetric detection, and fluorescence detection, have been applied to sweat analysis. Detecting glucose molecules in sweat using these strategies allows for the inference of blood sugar levels, calorie consumption, and other parameters, making it an important part of sweat detection.

[0004] Electrochemical methods for detecting glucose in sweat rely on the electrochemical reaction of substances on the electrode surface to detect the output current of a sensor, thus achieving accurate detection of the concentration of the analyte. However, electrochemical detection methods suffer from drawbacks such as complex structure, low portability, and high cost. Colorimetric methods depend on a colorimetric indicator to induce a color reaction in the analyte in sweat. Colorimetric sweat sensors are simple in structure and easy to manufacture, but their color change relies mainly on human visual perception, resulting in large errors, significant susceptibility to environmental interference, and inability to be used in dark environments. Summary of the Invention

[0005] To address the aforementioned problems in the prior art, this invention provides a porous hydrogel membrane for detecting glucose in sweat, along with its preparation and detection methods. The technical problem to be solved by this invention is achieved through the following technical solution:

[0006] A first aspect of the present invention provides a porous hydrogel film for detecting glucose in sweat, comprising: a carrier, rare earth nanoparticles modified with cobalt hydroxyoxide, and glucose oxidase;

[0007] The cobalt hydroxyoxide-modified rare earth nanoparticles and the glucose oxidase are distributed inside the carrier.

[0008] The cobalt hydroxyoxide is coated on the surface of the rare earth nanoparticles to form the cobalt hydroxyoxide-modified rare earth nanoparticles.

[0009] The cobalt hydroxyoxide is used to quench the fluorescence emission of the rare earth nanoparticles;

[0010] The carrier is formed by cross-linking polyacrylamide.

[0011] In one specific embodiment, the rare earth nanoparticles comprise NaGdF4: 30% Yb, 1% Er, and 5% Ce.

[0012] In one specific embodiment, the cobalt hydroxyoxide can react with hydrogen peroxide to generate divalent cobalt ions, which then detach from the surface of the rare earth nanoparticles.

[0013] In one specific embodiment, the wavelength of the laser includes 980 nm.

[0014] In one specific embodiment, the power of the laser is 0.2 to 0.6 W.

[0015] A second aspect of the present invention provides a method for preparing a porous hydrogel film for detecting glucose in sweat, used to prepare the porous hydrogel film provided in the first aspect of the present invention, comprising the following steps:

[0016] S1: Preparation of rare earth nanoparticles;

[0017] S2: Preparation of rare earth nanoparticles modified with cobalt hydroxyoxide;

[0018] S3: Acrylamide, N,N′-methylenebisacrylamide and K2S2O8 are dissolved in a second solvent to obtain a first gel solution; glucose oxidase and the rare earth nanoparticles modified with cobalt hydroxyoxide are added to the first gel solution, and the mixture is shaken to obtain a second gel solution; tetramethylethylenediamine solution is added to the second gel solution to obtain a porous hydrogel film with cross-linked polyacrylamide as the carrier.

[0019] In one specific embodiment, step S1 includes the following steps:

[0020] S101: Mix EDTA and the first solvent to obtain the first dispersion;

[0021] S102: Gd(NO3)3, Yb(NO3)3, Er(NO3)3 and Ce(NO3)3 are added to the first dispersion to obtain the second dispersion;

[0022] S103: Add sodium fluoride solution to the second dispersion to obtain a third dispersion;

[0023] S104: The third dispersion is placed under reaction conditions to carry out the reaction, and the reaction product is obtained after the reaction is completed;

[0024] S105: Perform a first post-treatment on the reaction product to obtain NaGdF4:30%Yb,1%Er,5%Ce rare earth nanoparticles after the first post-treatment.

[0025] In one specific embodiment, step S2 includes the following steps:

[0026] S201: Mix the rare earth nanoparticles, sodium hydroxide and sodium hypochlorite to obtain the fourth dispersion;

[0027] S202: The fourth dispersion is ultrasonically dispersed to obtain a fifth dispersion;

[0028] S203: Add cobalt chloride solution to the fifth dispersion to obtain the sixth dispersion;

[0029] S204: Perform a second post-treatment on the sixth dispersion to obtain rare earth nanoparticles modified with cobalt hydroxyoxide after the second post-treatment.

[0030] A third aspect of the present invention provides a method for detecting glucose in a porous hydrogel membrane of sweat, comprising:

[0031] Step 1: Prepare multiple artificial sweat samples containing different concentrations of glucose;

[0032] Step 2: Divide the multiple porous hydrogel films provided in the first aspect of the present invention into an artificial sweat film group and a sweat film group to be tested; contact each porous hydrogel film in the artificial sweat film group with one artificial sweat sample to obtain multiple first porous hydrogel films to be tested;

[0033] Step 3: Excite the plurality of first test porous hydrogel films using laser. After excitation, obtain the fluorescence intensity of the plurality of first test porous hydrogel films and establish a standard curve of the fluorescence intensity and the glucose concentration in the artificial sweat sample.

[0034] Step 4: Contact the porous hydrogel membrane in the sweat membrane group to be tested with the sweat to be tested to obtain the second porous hydrogel membrane to be tested;

[0035] Step 5: Excite the second porous hydrogel film to be tested using a laser. After the excitation is completed, obtain the fluorescence intensity of the second porous hydrogel film to be tested. Based on the fluorescence intensity of the second porous hydrogel film to be tested and the standard curve, obtain the glucose concentration in the sweat to be tested.

[0036] In a specific embodiment, the specific steps of step three are as follows:

[0037] The plurality of first test porous hydrogel films are excited using a 980nm laser. After excitation, a plurality of first excited porous hydrogel films are obtained. Fluorescence images of the plurality of first excited porous hydrogel films are captured through a 710nm short-pass filter. The fluorescence intensity of the plurality of first test porous hydrogel films is obtained based on the fluorescence images of the plurality of first excited porous hydrogel films. A standard curve is established between the fluorescence intensity and the glucose concentration in the artificial sweat sample.

[0038] The specific steps of step five are as follows:

[0039] The second porous hydrogel film to be tested is excited using a laser with a wavelength of 980 nm. After excitation, a second excited porous hydrogel film is obtained. A fluorescence image of the second excited porous hydrogel film is captured through a 710 nm short-pass filter. The fluorescence intensity of the second porous hydrogel film to be tested is obtained based on the fluorescence image of the second excited porous hydrogel film. The glucose concentration in the sweat to be tested is obtained based on the fluorescence intensity of the second porous hydrogel film to be tested and the standard curve.

[0040] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0041] This invention discloses a porous hydrogel membrane for detecting glucose in sweat. When exposed to sweat, sweat permeates into the interior of the membrane through its pores. Glucose oxidase within the membrane specifically catalyzes the formation of hydrogen peroxide from glucose in the sweat. The fluorescence emitted by the rare-earth nanoparticles within the membrane is initially quenched by the cobalt hydroxyl oxide coating on their surface. The hydrogen peroxide generated by glucose oxidase reacts with the cobalt hydroxyl oxide, causing it to detach from the surface of the rare-earth nanoparticles, thus restoring their fluorescence. The detection of glucose in sweat is achieved by observing the fluorescence intensity of the porous hydrogel membrane. This invention detects glucose in sweat using the principle of fluorescence resonance energy transfer, offering advantages such as high efficiency, stability, safety, and ease of use. The porous hydrogel membrane has a simple structure, is easy to manufacture, and is low in cost. Detection of glucose in sweat is achieved by observing the fluorescence intensity of the membrane, and it can operate even in dark environments. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of the structure of a porous hydrogel film for detecting glucose in sweat, provided in an embodiment of the present invention.

[0043] Figure 2 This is a scanning electron microscope image of rare earth nanoparticles provided in an embodiment of the present invention;

[0044] Figure 3 These are rare earth nanoparticles modified with cobalt hydroxyoxide provided in the embodiments of the present invention;

[0045] Figure 4 This is a standard curve graph provided in the embodiments of the present invention;

[0046] Figure 5 This is a fluorescence image of the second excited porous hydrogel film provided in an embodiment of the present invention;

[0047] Figure 6 This is a photograph of a porous hydrogel film for detecting glucose in sweat after being excited by a 980nm laser, according to an embodiment of the present invention.

[0048] Figure 7 The present invention provides a method for detecting glucose in sweat using a porous hydrogel film. After excitation with a 980nm laser, multiple fluorescence images of the first excited porous hydrogel film are captured through a 710nm short-pass filter.

[0049] Figure 8 This is a physical image of a carrier formed by cross-linking rare earth nanoparticles without cobalt hydroxyl oxide modification and polyacrylamide containing glucose oxidase after being excited by a 980nm laser.

[0050] Figure 9 The image is a fluorescence image captured by a 710nm short-pass filter after the carrier formed by cross-linking rare earth nanoparticles without cobalt hydroxyl oxide modification and glucose oxidase with polyacrylamide was excited by a 980nm laser.

[0051] Figure label:

[0052] 1: Polyacrylamide; 2: Rare earth nanoparticles; 3: Cobalt hydroxyoxide; 4: Glucose oxidase. Detailed Implementation

[0053] The present invention will be further described in detail below with reference to specific embodiments, but the implementation of the present invention is not limited thereto.

[0054] Example 1

[0055] Please see Figure 1 A porous hydrogel film for detecting glucose in sweat includes: a carrier, cobalt hydroxyoxide-modified rare earth nanoparticles, and glucose oxidase 4. The cobalt hydroxyoxide-modified rare earth nanoparticles and glucose oxidase 4 are distributed within the carrier. Cobalt hydroxyoxide 3 coats the surface of the rare earth nanoparticles 2 to form cobalt hydroxyoxide-modified rare earth nanoparticles. Cobalt hydroxyoxide 3 is used to quench the fluorescence emission of the rare earth nanoparticles 2. The carrier is formed by cross-linking with polyacrylamide 1.

[0056] Specifically, the rare earth nanoparticles 2 in the porous hydrogel film emit fluorescence after laser excitation, but the cobalt hydroxyl oxide 3 coating the surface of the rare earth nanoparticles 2 quenches the fluorescence. The porous hydrogel film has pores that allow sweat to pass through. Sweat permeates into the interior of the film through the pores, and glucose oxidase 4 inside the film specifically catalyzes the glucose in the sweat to generate hydrogen peroxide. The cobalt hydroxyl oxide 3 reacts with the hydrogen peroxide to generate divalent cobalt ions, which then detach from the surface of the rare earth nanoparticles 2, thereby restoring the fluorescence of the rare earth nanoparticles 2.

[0057] Furthermore, the rare earth nanoparticles 2 comprise NaGdF4: 30% Yb, 1% Er, and 5% Ce. Cobalt hydroxyoxide 3 reacts with hydrogen peroxide to generate divalent cobalt ions, which then detach from the surface of the rare earth nanoparticles 2. The laser wavelength includes 980 nm, and the laser power ranges from 0.2 to 0.6 W.

[0058] Specifically, NaGdF4:30%Yb,1%Er,5%Ce rare earth nanoparticles 2 emit green fluorescence under 980nm laser excitation, and the fluorescence intensity of the porous hydrogel film under laser excitation is proportional to the glucose concentration in sweat. Figure 6 This is a photograph of the porous hydrogel film in this embodiment after being excited by a 980nm laser. Figure 7 This is a fluorescence image of the porous hydrogel film in this embodiment, obtained by excitation with a 980nm laser and then passing through a 710nm short-pass filter. Figure 8 Image of a support formed by cross-linking rare earth nanoparticles without cobalt hydroxyl oxide modification and polyacrylamide 1 containing glucose oxidase 4, after excitation with a 980 nm laser. Figure 9 Fluorescence images of a support formed by cross-linking rare earth nanoparticles without cobalt hydroxyl oxide modification and polyacrylamide 1 containing glucose oxidase 4, excited by a 980 nm laser and captured through a 710 nm short-pass filter, are compared with those obtained by cross-linking. Figure 6 , Figure 7 , Figure 8 and Figure 9 The porous hydrogel film in this embodiment can be clearly seen to emit green fluorescence, while the carrier formed by the cross-linking of rare earth nanoparticles modified with cobalt hydroxyl oxide and polyacrylamide 1 with glucose oxidase 4 without the addition of cobalt hydroxyl oxide does not fluoresce.

[0059] This embodiment provides a porous hydrogel membrane for detecting glucose in sweat. When exposed to sweat, sweat permeates into the interior of the porous hydrogel membrane through its pores. Glucose oxidase 4 within the membrane specifically catalyzes the formation of hydrogen peroxide from glucose in sweat. The fluorescence emission of rare earth nanoparticles 2 within the membrane, initially quenched by cobalt hydroxyl oxide 3 covering their surface, reacts with the hydrogen peroxide generated by glucose oxidase 4, causing the cobalt hydroxyl oxide to detach from the surface of the rare earth nanoparticles 2, thus restoring their fluorescence. The detection of glucose in sweat is achieved by observing the green fluorescence intensity of the membrane. This method of detecting glucose in sweat using the principle of fluorescence resonance energy transfer (FRET) offers advantages such as high efficiency, stability, safety, and ease of use. The porous hydrogel membrane has a simple structure, is easy to manufacture, and is low in cost. It can operate even in dark environments. Using cross-linked polyacrylamide 1 as the main body of the porous hydrogel membrane allows it to cover the surface of the skin to be tested, making it easy to carry and use.

[0060] Example 2

[0061] A method for preparing a porous hydrogel membrane for detecting glucose in sweat, used to prepare the porous hydrogel membrane provided in Example 1 of this invention, includes the following steps:

[0062] S1: Preparation of rare earth nanoparticles;

[0063] Further, step S1 includes the following steps:

[0064] S101: Mix EDTA and the first solvent to obtain the first dispersion;

[0065] Specifically, 15 ml of ultrapure water was added to a beaker, 1 mmol of EDTA was weighed and dissolved, and the first dispersion was obtained after dissolution.

[0066] S102: Gd(NO3)3, Yb(NO3)3, Er(NO3)3 and Ce(NO3)3 are added to the first dispersion to obtain the second dispersion;

[0067] Specifically, 0.64 mmol Gd(NO3)3, 0.3 mmol Yb(NO3)3, 0.01 mmol Er(NO3)3 and 0.05 mmol Ce(NO3)3 were added to the first dispersion, and the mixture was stirred for one hour. After stirring, the second dispersion was obtained.

[0068] S103: Add sodium fluoride solution to the second dispersion to obtain the third dispersion;

[0069] Specifically, 10 mL of sodium fluoride solution with a concentration of 0.04198 g / mL was added to the second dispersion, and the mixture was stirred for 1 hour. After stirring, the third dispersion was obtained.

[0070] S104: The third dispersion is placed under reaction conditions and the reaction is carried out. After the reaction is completed, the reaction product is obtained.

[0071] Specifically, the third dispersion was poured into the reactor and reacted in an oven at 180°C for 3 hours. After the reaction was completed, the reactor was opened after natural cooling to obtain the reaction product.

[0072] S105: The reaction product is subjected to a first post-treatment. After the first post-treatment, NaGdF4:30%Yb,1%Er,5%Ce rare earth nanoparticles are obtained.

[0073] Preferably, the first post-treatment includes centrifugation and drying.

[0074] Specifically, the supernatant of the reaction product was discarded, and the product was centrifuged for 7 minutes at 7500 rpm. The supernatant was discarded again after the first centrifugation. Ultrapure water was added, and a second centrifugation was performed, after which the supernatant was discarded. A third centrifugation was performed at 7500 rpm for 7 minutes, after which the supernatant was discarded, yielding the centrifuged product. The product was then dried in an oven at 80°C for 3 hours, yielding NaGdF4:30%Yb,1%Er,5%Ce rare earth nanoparticles. The scanning electron microscope (SEM) image of the NaGdF4:30%Yb,1%Er,5%Ce rare earth nanoparticles prepared in this step is shown below. Figure 2 As shown.

[0075] S2: Preparation of rare earth nanoparticles modified with cobalt hydroxyoxide;

[0076] Further, step S2 includes the following steps:

[0077] S201: Rare earth nanoparticles, sodium hydroxide and sodium hypochlorite are mixed to obtain the fourth dispersion;

[0078] Specifically, 1 mL of rare earth nanoparticles with a concentration of 10 mg / mL, 2 mL of sodium hydroxide with a concentration of 0.8 M, and 2 mL of sodium hypochlorite with a concentration of 0.2 M were added to a 50 mL centrifuge tube to obtain the fourth dispersion.

[0079] S202: The fourth dispersion is ultrasonically dispersed to obtain the fifth dispersion;

[0080] S203: Add cobalt chloride solution to the fifth dispersion to obtain the sixth dispersion;

[0081] Specifically, under ultrasonic treatment, 0.9523 mL of 0.01 M cobalt chloride solution was added to the fifth dispersion to obtain the sixth dispersion.

[0082] S204: The sixth dispersion is subjected to a second post-treatment, and rare earth nanoparticles modified with cobalt hydroxyoxide are obtained after the second post-treatment.

[0083] Specifically, the second post-processing includes centrifugation and drying.

[0084] Preferably, the sixth dispersion is centrifuged three times and dried in an oven at 60°C to obtain rare earth nanoparticles modified with cobalt hydroxyl oxide. A scanning electron microscope image of the cobalt hydroxyl oxide-modified rare earth nanoparticles prepared in this step is shown below. Figure 3 As shown.

[0085] S3: Acrylamide, N,N′-methylenebisacrylamide and K2S2O8 are dissolved in a second solvent to obtain a first gel solution. Glucose oxidase and rare earth nanoparticles modified with cobalt hydroxyoxide are added to the first gel solution. After shaking, a second gel solution is obtained. Tetramethylethylenediamine solution is added to the second gel solution to obtain a porous hydrogel film with cross-linked polyacrylamide as the carrier.

[0086] Specifically, 0.6 g of acrylamide, 0.01 g of N,N′-methylenebisacrylamide, and 0.01 g of K₂S₂O₈ were dissolved in 2 mL of deionized water to obtain a first gel solution. Then, 2 mL of a 5 mg / mL aqueous solution of cobalt hydroxyl oxide-modified rare earth nanoparticles and 2 mg of glucose oxidase were added to the first gel solution, and the mixture was shaken well to obtain a second gel solution. 10 μL of tetramethylethylenediamine solution was added to the second gel solution, and the mixture was poured into a mold. After natural cooling, a hydrogel film with cross-linked polyacrylamide as a carrier was formed.

[0087] This embodiment provides a method for preparing a porous hydrogel film for detecting glucose in sweat. The method involves coating rare earth nanoparticles with cobalt hydroxyl oxide to form cobalt hydroxyl oxide-modified rare earth nanoparticles. Glucose oxidase and the cobalt hydroxyl oxide-modified rare earth nanoparticles are dispersed within the porous hydrogel film. The detection of glucose in sweat is achieved by observing the green fluorescence intensity of the film. This preparation method is simple, low-cost, and produces uniformly coated cobalt hydroxyl oxide-modified rare earth nanoparticles. The method allows for the detection of glucose in sweat by observing the green fluorescence intensity of the film and can operate even in dark environments.

[0088] Example 3

[0089] A method for detecting glucose in a porous hydrogel membrane of sweat, comprising:

[0090] Step 1: Prepare multiple artificial sweat samples containing different concentrations of glucose;

[0091] Specifically, 200 mg of sodium chloride, 175 mg of ammonium chloride, 50 mg of urea, and 25 mg of acetic acid were dissolved in 10 ml of water. The pH was measured and adjusted to 5.5 using sodium hydroxide solution to obtain the initial artificial sweat sample. 0.0396 g, 0.0793 g, 0.1189 g, 0.1585 g, and 0.1982 g of glucose were added to 1 mL of the initial artificial sweat sample, respectively, to obtain artificial sweat samples containing 0.2 M, 0.4 M, 0.6 M, 0.8 M, and 1.0 M glucose, respectively.

[0092] Step 2: Divide the porous hydrogel films provided in Embodiment 1 of the present invention into an artificial sweat film group and a test sweat film group. Contact each porous hydrogel film in the artificial sweat film group with an artificial sweat sample to obtain multiple first test porous hydrogel films.

[0093] Specifically, 100 μL of artificial sweat samples containing different concentrations of glucose were taken and dropped onto the surface of the porous hydrogel membrane in the artificial sweat membrane group. Each concentration of artificial sweat sample was dropped onto the surface of a corresponding porous hydrogel membrane. After the artificial sweat sample and the porous hydrogel membrane were in contact for 15 minutes, multiple first porous hydrogel membranes to be tested were obtained.

[0094] Step 3: Excite multiple first-test porous hydrogel films using laser. After excitation, obtain the fluorescence intensity of multiple first-test porous hydrogel films and establish a standard curve of fluorescence intensity and glucose concentration in artificial sweat samples.

[0095] Specifically, multiple first-stage porous hydrogel films to be tested are excited using a 980nm laser. After excitation, multiple first-stage excited porous hydrogel films are obtained. Fluorescence images of the multiple first-stage excited porous hydrogel films are captured through a 710nm short-pass filter. The fluorescence intensity of the multiple first-stage tested porous hydrogel films is obtained based on the fluorescence images, and a standard curve is established between fluorescence intensity and glucose concentration in artificial sweat samples. The standard curve obtained in this step is shown below. Figure 4 As shown.

[0096] Preferably, a mobile phone is used to capture green fluorescence images of multiple first-excited porous hydrogel films through a 710nm short-pass filter, and the green channels of the fluorescence images of multiple first-excited porous hydrogel films are segmented using ImageJ software to delineate the fluorescence regions, and the fluorescence intensity is quantitatively analyzed. This process is repeated three times to obtain the fluorescence intensity of multiple first-excited porous hydrogel films to be tested.

[0097] Step 4: Contact the porous hydrogel membrane in the sweat membrane group to be tested with the sweat to be tested to obtain the second porous hydrogel membrane to be tested.

[0098] Specifically, 100 μL of the sweat sample to be tested is dropped onto the surface of the porous hydrogel membrane in the sweat sample membrane group. After the sweat sample and the porous hydrogel membrane are in contact for 15 minutes, a second porous hydrogel membrane to be tested is obtained. The number of sweat samples corresponds to the number of porous hydrogel membranes. If there is one sample of sweat sample, one porous hydrogel membrane is taken from the sweat sample membrane group for testing; if there are two samples of sweat sample, two porous hydrogel membranes are taken from the sweat sample membrane group for testing. During the testing process, the sweat sample can be collected and dropped onto the surface of the porous hydrogel membrane, or the porous hydrogel membrane can be placed on the skin surface of the person being tested. Generally, the skin to be tested is an area of ​​the human body with more sweat, such as the arms, forehead, and back of the neck, but the choice can be flexible according to actual needs.

[0099] Step 5: Excite the second porous hydrogel film to be tested using a laser. After the excitation is completed, obtain the fluorescence intensity of the second porous hydrogel film to be tested. Based on the fluorescence intensity of the second porous hydrogel film to be tested and the standard curve, obtain the glucose concentration in the sweat to be tested.

[0100] The second porous hydrogel film to be tested was excited using a laser with a wavelength of 980 nm. After excitation, the second excited porous hydrogel film was obtained. The fluorescence image of the second excited porous hydrogel film was captured through a 710 nm short-pass filter. The fluorescence intensity of the second porous hydrogel film to be tested was obtained from the fluorescence image of the second excited porous hydrogel film. The glucose concentration in the sweat to be tested was obtained from the value corresponding to the fluorescence intensity of the second porous hydrogel film to be tested in the standard curve.

[0101] Preferably, a fluorescence image of the second excited porous hydrogel film is captured by a mobile phone through a 710nm short-pass filter, and the green channel of the fluorescence image of the second excited porous hydrogel film is segmented by ImageJ software to delineate the fluorescence region, and the fluorescence intensity is quantitatively analyzed. This process is repeated three times to obtain the fluorescence intensity of the second porous hydrogel film to be tested.

[0102] In this embodiment, sweat samples were extracted from three volunteers as three groups of test samples. The fluorescence images obtained after performing steps four and five on the three groups of test samples are shown below. Figure 5 As shown, observe Figure 5 The fluorescence image shown can be used to preliminarily determine the glucose concentration in sweat. Figure 5 The fluorescence intensity was obtained from the fluorescence image shown and then entered into the image. Figure 4 The standard curve shown can be used to obtain the glucose concentration in the sweat of the three volunteers.

[0103] This embodiment provides a detection method for glucose in sweat using a porous hydrogel membrane. This method is highly efficient and stable, offering advantages such as the safety and ease of use. The method involves simply adding the sweat sample to the surface of the porous hydrogel membrane or using the membrane itself. After covering the skin surface, the membrane is laser-excited, and the fluorescence intensity is obtained to detect glucose in the sweat. The method is convenient, simple, and applicable to various scenarios. Glucose in sweat is detected by observing the green fluorescence intensity of the membrane, and it can operate even in dark environments.

[0104] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such modifications and substitutions should be considered within the scope of protection of the present invention.

Claims

1. A porous hydrogel membrane for detecting glucose in sweat, characterized in that, include: Carrier, cobalt hydroxyoxide-modified rare earth nanoparticles, and glucose oxidase; The cobalt hydroxyoxide-modified rare earth nanoparticles and the glucose oxidase are distributed inside the carrier. The cobalt hydroxyoxide is coated on the surface of the rare earth nanoparticles to form the cobalt hydroxyoxide-modified rare earth nanoparticles. The rare earth nanoparticles comprise NaGdF4:30%Yb,1%Er,5%Ce, and are used to emit fluorescence after laser excitation. The cobalt hydroxyoxide is used to quench the fluorescence emission of the rare earth nanoparticles; The carrier is formed by cross-linking polyacrylamide.

2. The porous hydrogel membrane for detecting glucose in sweat according to claim 1, characterized in that, The cobalt hydroxyoxide can react with hydrogen peroxide to generate divalent cobalt ions, which then detach from the surface of the rare earth nanoparticles.

3. The porous hydrogel membrane for detecting glucose in sweat according to claim 1, characterized in that, The wavelength of the laser includes 980nm.

4. A porous hydrogel membrane for detecting glucose in sweat according to claim 1, characterized in that, The power of the laser is 0.2~0.6 W.

5. A method for preparing a porous hydrogel membrane for detecting glucose in sweat, used to prepare the porous hydrogel membrane as described in any one of claims 1 to 4, characterized in that, Includes the following steps: S1: Preparation of rare earth nanoparticles; S2: Preparation of rare earth nanoparticles modified with cobalt hydroxyoxide; S3: Acrylamide, N,N′-methylenebisacrylamide and K2S2O8 are dissolved in a second solvent to obtain a first gel solution; glucose oxidase and the rare earth nanoparticles modified with cobalt hydroxyoxide are added to the first gel solution, and the mixture is shaken to obtain a second gel solution; A tetramethylethylenediamine solution was added to the second gel solution to obtain a porous hydrogel film with cross-linked polyacrylamide as the carrier.

6. The method for preparing a porous hydrogel film for detecting glucose in sweat according to claim 5, characterized in that, Step S1 includes the following steps: S101: Mix EDTA and the first solvent to obtain the first dispersion; S102: Gd(NO3)3, Yb(NO3)3, Er(NO3)3 and Ce(NO3)3 are added to the first dispersion to obtain the second dispersion; S103: Add sodium fluoride solution to the second dispersion to obtain a third dispersion; S104: The third dispersion is placed under reaction conditions to carry out the reaction, and the reaction product is obtained after the reaction is completed; S105: Perform a first post-treatment on the reaction product to obtain NaGdF4:30%Yb,1%Er,5%Ce rare earth nanoparticles after the first post-treatment.

7. The method for preparing a porous hydrogel film for detecting glucose in sweat according to claim 5, characterized in that, Step S2 includes the following steps: S201: Mix the rare earth nanoparticles, sodium hydroxide and sodium hypochlorite to obtain the fourth dispersion; S202: The fourth dispersion is ultrasonically dispersed to obtain a fifth dispersion; S203: Add cobalt chloride solution to the fifth dispersion to obtain the sixth dispersion; S204: Perform a second post-treatment on the sixth dispersion to obtain rare earth nanoparticles modified with cobalt hydroxyoxide after the second post-treatment.

8. A method for detecting glucose in a porous hydrogel membrane of sweat, characterized in that, include: Step 1: Prepare multiple artificial sweat samples containing different concentrations of glucose; Step 2: Divide the multiple porous hydrogel films as described in any one of claims 1 to 4 into an artificial sweat film group and a sweat film group to be tested; contact each porous hydrogel film in the artificial sweat film group with one artificial sweat sample to obtain multiple first porous hydrogel films to be tested. Step 3: Excite the plurality of first test porous hydrogel films using laser. After excitation, obtain the fluorescence intensity of the plurality of first test porous hydrogel films and establish a standard curve of the fluorescence intensity and the glucose concentration in the artificial sweat sample. Step 4: Contact the porous hydrogel membrane in the sweat membrane group to be tested with the sweat to be tested to obtain the second porous hydrogel membrane to be tested; Step 5: Excite the second porous hydrogel film to be tested using a laser. After the excitation is completed, obtain the fluorescence intensity of the second porous hydrogel film to be tested. Based on the fluorescence intensity of the second porous hydrogel film to be tested and the standard curve, obtain the glucose concentration in the sweat to be tested.

9. The method for detecting glucose in sweat using a porous hydrogel membrane according to claim 8, characterized in that, The specific steps of step three are as follows: The plurality of first test porous hydrogel films are excited using a 980 nm laser. After excitation, a plurality of first excited porous hydrogel films are obtained. Fluorescence images of the plurality of first excited porous hydrogel films are captured through a 710 nm short-pass filter. The fluorescence intensity of the plurality of first test porous hydrogel films is obtained based on the fluorescence images of the plurality of first excited porous hydrogel films. A standard curve is established between the fluorescence intensity and the glucose concentration in the artificial sweat sample. The specific steps of step five are as follows: The second porous hydrogel film to be tested is excited using a laser with a wavelength of 980 nm. After excitation, a second excited porous hydrogel film is obtained. A fluorescence image of the second excited porous hydrogel film is captured through a 710 nm short-pass filter. The fluorescence intensity of the second porous hydrogel film to be tested is obtained based on the fluorescence image of the second excited porous hydrogel film. The glucose concentration in the sweat to be tested is obtained based on the fluorescence intensity of the second porous hydrogel film to be tested and the standard curve.

Images