CN114935572A - A visualization method for uric acid detection based on nanomaterials - Google Patents

Abstract

The invention provides a visual uric acid detection method based on nanomaterials, which is applied in the field of chemical testing. 5,5'-Tetramethylbenzidine (TMB) is a chromogenic reagent, which can be used for rapid detection and analysis of uric acid content according to the chromogenic intensity. Existing chromogenic methods for uric acid detection mostly use peroxidase or uric acid oxidase to achieve the bottom line. However, the long-term stability of enzyme preparations is easily affected by storage conditions; the present invention utilizes the peroxidase-like effect of gold nanoparticles with positive charges on the surface to realize the visual detection of enzyme-free uric acid. At the same time, we design The small-sized portable uric acid detection kit can be directly used for the detection of uric acid in urine by breaking the cotton swab and then immersing it in the matching reagent tube, which is convenient for the daily use of the elderly population.

Description

A visualization method for uric acid detection based on nanomaterials

technical field

The invention relates to the field of chemical testing, in particular to a visual uric acid detection method based on nanomaterials.

Background technique

Existing chromogenic methods for uric acid detection mostly use peroxidase or uric acid oxidase to achieve discoloration of the substrate, but the long-term stability of enzyme preparations is easily affected by storage conditions, and the storage conditions of enzyme reagents are strict and the cost is high .

SUMMARY OF THE INVENTION

The present invention aims to solve the problems of using enzymes for uric acid detection, but the storage conditions of enzyme reagents are strict and the cost is relatively high, and provides a visual uric acid detection method based on nanomaterials.

The present invention adopts the following technical means for solving the technical problem:

The present invention provides a visual uric acid detection method based on nanomaterials, comprising:

S1: break apart the cotton swabs to be tested, make the cotton swabs to be tested react with the air pressure, and fall to the bottom end of the cotton swabs to obtain the first cotton swabs to be tested with positively charged gold nanoparticles on the surface;

S2: the first cotton swab to be tested is placed in a preset hydrogen peroxide solution for reaction to obtain a second cotton swab to be tested with hydroxide radicals;

S3: placing the second cotton swab to be tested in a preset uric acid detection kit to react with the urine of the corresponding patient to obtain a test cotton swab with uric acid content;

S4: determine whether the test cotton swab changes to a preset color;

S5: If yes, the uric acid of the patient undergoing the uric acid test is too high.

Further, break apart the cotton swab to be tested, so that the cotton swab to be tested reacts with the air pressure, and falls to the bottom end of the cotton swab to obtain the first cotton swab to be tested of positively charged gold nanoparticles on the surface. In step S1, the preparation process of the gold nanoparticles with positive charges on the surface includes the following steps:

Add chloroauric acid and ascorbic acid solution into double distilled water, stir while heating, until the color of the solution changes from initial yellow to red, then the nano-gold particle solution can be obtained;

The carbon dots are added to the gold nanoparticle solution, and the gold nanoparticles with positive surface charges are obtained when the carbon dots completely wrap the gold nanoparticles.

Further, adding chloroauric acid and ascorbic acid solution into double-distilled water, stirring while heating, until the color of the solution changes from initial yellow to red, the steps of obtaining the nano-gold particle solution also include:

The heating temperature is limited to the interval of 30-50°C.

Further, in the step S4 of judging whether the test cotton swab changes into a preset color, it also includes:

The carbon dot gold nanometer encounters hydrogen peroxide to generate hydroxide, and the carbon dot gold nanometer reacts with 3,3',5,5'-tetramethylbenzidine and transforms into colorless or blue 3 ,3',5,5'-tetramethylbenzidine.

Further, the carbon dot gold nanometer encounters hydrogen peroxide to generate hydroxide, and the carbon dot gold nanometer reacts with 3,3',5,5'-tetramethylbenzidine and changes to colorless or blue. After the steps of coloring 3,3',5,5'-tetramethylbenzidine, include:

The colorless 3,3',5,5'-tetramethylbenzidine is uric acid without excessive reaction, and the blue 3,3',5,5'-tetramethylbenzidine is uric acid overreaction.

Further, in the step S3 of placing the second cotton swab to be tested in a preset uric acid detection kit and reacting with the urine of the corresponding patient to obtain a test cotton swab with uric acid content, it also includes:

3,3',5,5'-tetramethylbenzidine was used as a chromogenic agent to react with the urine of the corresponding patient.

Further, the preparation steps of 3,3',5,5'-tetramethylbenzidine include:

The undegraded 2,6-dimethylaniline is added to absolute ethanol, the pre-prepared deionized aqueous solution with hydrogen peroxide solution is added to the absolute ethanol, the oxidant is added dropwise, and after the dropwise addition is completed, the mixture is stirred until the solid is precipitated, The solid was filtered off with suction, washed with water and ethanol and air-dried to obtain 2,6-dimethylaniline degraded;

The degraded 2,6-dimethylaniline is added to the aqueous solution in which ammonium chloride is dissolved, and then glacial acetic acid is added to stir, and the temperature is adjusted to 15° C.-20° C. during the stirring process until the solid is precipitated. The solid is vacuum filtered, and the degree of vacuum is greater than or equal to 0.08MPa to obtain the crude product of 3,3,5,5-tetramethylbenzidine;

The 3,3,5,5-tetramethylbenzidine crude product was added to the pre-prepared methanol, and the temperature was raised to 70° C. and waited for the reaction, until the concentrated compound was obtained after the concentrated reaction, and the concentrated compound was obtained. Add to ethanol, continue to heat up to 80°C, stop the temperature rise and filter to obtain the finished product of 3,3,5,5-tetramethylbenzidine.

Further, the degraded 2,6-dimethylaniline is added to the aqueous solution dissolved in ammonium chloride, and then glacial acetic acid is added for stirring, and the temperature is adjusted to 15°C-20°C during the stirring process, until the solid is precipitated. , carry out vacuum filtration on the solid, the vacuum degree is ≥ 0.08MPa, in the step of obtaining the crude product of 3,3,5,5-tetramethylbenzidine, it also includes:

The solid is stirred and washed with water, filtered with suction, repeated twice, and dried in an environment of 45-60° C. for 2-3 hours to obtain an activated solid;

The activated solid was dissolved in 2-5 times of dichloromethane, 1-4 times of benzyl chloride was added, the reaction solution was placed in an aqueous solution at 30°C to 45°C, and taken out after reacting for 2-3 hours to obtain the Crude activated solid;

The crude product of the activated solid was added to a solution with 10% sodium acetate methanol, stirred and washed with methanol and then suction filtered, washed the crude product until the suction filtrate did not change color when exposed to water, and dried at 45-60°C , to get the active bolded boutique.

Further, in the step S2 of placing the first cotton swab to be tested in a preset hydrogen peroxide solution to react to obtain the second cotton swab to be tested with hydroxide radicals, the preset peroxide The preparation steps of the hydrogen solution include:

Add medium water to the preset anode plate end;

Feed reaction O ₂ at the preset cathode electrode end;

Connecting the anode electrode plate end and the cathode electrode plate end with an external power source to form an electrolysis path;

The medium water is decomposed into products O ₂ and H ⁺ on the end of the anode electric plate after electrolysis reaction, and the product O ₂ is discharged through the drain port on the end of the anode electric plate;

The H ⁺ reaches the cathode through the cathode electrode plate end, and combines with the reaction O ₂ fed in to generate the product H ₂ O ₂ . After the product H ₂ O ₂ is discharged through the exhaust port on the cathode end plate, to collect.

Further, the temperature of the electrolysis reaction is set between 20°C and 50°C.

The present invention provides a visual uric acid detection method based on nanomaterials, which has the following beneficial effects:

The invention adopts portable visual detection, has low detection cost, simple operation, is convenient for the elderly to operate, and realizes non-enzyme detection, improves the stability of the reagent, and can realize the daily self-examination of uric acid content at low cost, simply and quickly.

Description of drawings

FIG. 1 is a schematic flowchart of an embodiment of a method for visualizing uric acid detection based on nanomaterials according to the present invention.

Detailed ways

It should be understood that the specific embodiments described herein are only used to explain the present invention, not to limit the present invention. The realization, functional characteristics and advantages of the present invention will be further described with reference to the accompanying drawings in conjunction with the embodiments.

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the implementations. example. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

Referring to accompanying drawing 1, it is a nanomaterial-based visual uric acid detection method in an embodiment of the present invention, comprising the following steps:

S1: break apart the cotton swabs to be tested, make the cotton swabs to be tested react with the air pressure, and fall to the bottom end of the cotton swabs to obtain the first cotton swabs to be tested with positively charged gold nanoparticles on the surface;

S2: the first cotton swab to be tested is placed in a preset hydrogen peroxide solution for reaction to obtain a second cotton swab to be tested with hydroxide radicals;

S3: placing the second cotton swab to be tested in a preset uric acid detection kit to react with the urine of the corresponding patient to obtain a test cotton swab with uric acid content;

S4: determine whether the test cotton swab changes to a preset color;

S5: If yes, the uric acid of the patient undergoing the uric acid test is too high.

In this embodiment,

Experimental materials: chloroauric acid (HAuCl·4H ₂ O), ascorbic acid, H ₂ O ₂ , methanol, tetramethylbenzidine, n-heptane, xanthine, hypoxanthine, creatinine, inosine, glucose and uric acid, etc. All of them are of analytical grade; alkyl ketene dimer; vacuum silicone grease; human serum samples; double distilled water.

Experimental procedure: 50 μL (0.1 mol/L) chloroauric acid and 50 μL (24 g/L) ascorbic acid solution were added to 10 mL double distilled water, and stirred at 40 °C for 2 min. The color of the solution rapidly changed from light yellow to bright red, and the positively charged AuNPs were obtained.

Preparation of uric acid solution: Weigh 0.02 g of uric acid standard and dissolve it in a freshly prepared 10 mL NaOH (0.1 mol/L) solution to obtain a 2 g/L uric acid stock solution. When using, it was diluted with double distilled water to 0, 25, 50, 75, 100 and 125 mg/L uric acid standard solution respectively.

Detection of uric acid: When the colorless mixed solution of TMB and H ₂ O ₂ encounters the (+) AuNPs of the positive electrode, the (+) AuNPs of the positive electrode have the properties of peroxidase-mimicking enzymes, and TMB is quickly catalyzed by it. H ₂ O ₂ is oxidized to blue-green. After adding uric acid, the oxidized TMB is reduced to colorless by uric acid, and the degree of color change is proportional to the content of uric acid. That is, when the patient's uric acid content is too high, the color of TMB presented is blue; When the patient's uric acid content is normal, the TMB color presented is colorless.

Uric acid detection method: take TMB methanol solution with a concentration of 0.02 mol/L and 8.82 mol/L H ₂ O ₂ aqueous solution in a volume ratio of 5:1 to be mixed as a color developing solution; take 2 μL of positive (+) AuNPs solution for ingestion. Put it into the cotton swab to be tested, then ingest 2 μL of chromogenic solution, the detection area turns blue, take standard solutions of uric acid with different concentrations, put the cotton swab to be tested into the detection area in turn, the blue rapidly becomes lighter, and at 1.5 It tends to be stable at min, and the gray value is obtained (the darker the blue, the smaller the gray value).

HPLC determination of uric acid in serum The uric acid value in serum was compared and analyzed by HPLC. The chromatographic conditions were as follows: ACE 5 AQ aqueous column (250mmx4.6mm, 5μm), detection wavelength 254nm, column temperature 25℃, gradient elution, The mobile phase consisted of acetic acid solution (solvent A) and acetonitrile (solvent B) at pH=3. The gradient program was that solvent A was maintained for 20 min, and then the volume fraction of solvent B was increased to 40% within 10 min and maintained for 5 min, with a flow rate of 1 mL/min.

In the present embodiment, the cotton swab to be tested is broken apart, so that the cotton swab to be tested reacts with the air pressure and falls to the bottom end of the cotton swab to obtain the first cotton swab to be tested with carbon dots gold nanometers. In step S1, the preparation process of the carbon dot gold nanometer includes the following steps:

Add chloroauric acid and ascorbic acid solution into double distilled water, stir while heating, until the color of the solution changes from initial yellow to red, then the nano-gold particle solution can be obtained;

The carbon dots are added to the gold nanoparticle solution, and the gold nanoparticles with positive surface charges are obtained when the carbon dots completely wrap the gold nanoparticles.

In this embodiment,

Experimental materials: chloroauric acid, double distilled water, sodium hydroxide, amino, hydroxyl, citric acid, carbon dots, gold nanoparticles;

Experimental procedure: 10 mL of 15mM chloroauric acid solution was added to 8 mL of 55 mg/mL BSA solution, stirred for 30 min at 800 rpm in a water bath at 50 °C, and 800 μL of 1 M NaOH solution was added, and the mixed solution was heated at 50 °C Continuous stirring for 7 h, centrifuged at 6000 rpm for 5 min, the supernatant was dialyzed with a 1 000 Da dialysis bag and freeze-dried to obtain an activated solid;

Prepare the carbon dot solution with amino and carboxyl groups on the surface, put the mixture into a hydrothermal reactor, evaporate to dryness at 70 °C, and react at 220 °C for 2 h to obtain carbon dot solids; dissolve the carbon dot solids in 100 mL Water, add 1M NaOH solution to pH 7, centrifuge at 6 000 rpm for 5 min, and dialyze the supernatant with a 1000 Da dialysis bag to obtain carbon dots;

The activated solid and carbon dots are directly mixed and dropped into gold nanoparticles to obtain carbon dots and gold nanoparticles.

In the present embodiment, adding chloroauric acid and ascorbic acid solution into double distilled water, stirring while heating, until the color of the solution changes from the initial yellow to red, the nano-gold particle solution can be obtained in the step, which also includes the following steps: :

The heating temperature is limited to the interval of 30-50°C.

In this embodiment,

Experimental materials: chloroauric acid, ascorbic acid solution, double distilled water, gold nanoparticles;

Add chloroauric acid and ascorbic acid solution to double-distilled water, heat to 30 °C while stirring, until the color of the solution changes from the initial yellow to red, then the nano-gold particle solution can be obtained; While stirring, the color of the nano-gold particle solution changes slowly, and the nano-gold particle solution cannot be changed in time, which is not suitable for preparing the nano-gold particle solution.

Add chloroauric acid and ascorbic acid solution to double distilled water, and stir while heating to 40 °C until the color of the solution changes from the initial yellow to red, and then the nano-gold particle solution can be obtained; While stirring, the color of the nano-gold particle solution changes moderately, and the nano-gold particle solution can be changed at an appropriate experimental time, which is suitable for preparing the nano-gold particle solution.

Add chloroauric acid and ascorbic acid solution to double-distilled water, heat to 50 °C while stirring, until the color of the solution changes from the initial yellow to red, then the nano-gold particle solution can be obtained; While stirring, the color of the gold nanoparticle solution is fast, and the color is too dark red. The prepared gold nanoparticle solution contains precipitation, which is not suitable for preparing the gold nanoparticle solution.

In this embodiment, the step S4 of judging whether the test cotton swab changes to a preset color further includes:

The carbon dot gold nanometer encounters hydrogen peroxide to generate hydroxide, and the carbon dot gold nanometer reacts with 3,3',5,5'-tetramethylbenzidine and transforms into colorless or blue 3 ,3',5,5'-tetramethylbenzidine.

In this embodiment,

Experimental materials: carbon dots gold nanoparticles, methanol solution, H ₂ O ₂ , 3,3',5,5'-tetramethylbenzidine (TMB), test cotton swab;

Experimental process: take the methanol solution of TMB with a concentration of 0.02 mol/L and the aqueous H ₂ O ₂ solution of 8.82 mol/L in a volume ratio of 5:1 to be used as the color developing solution. Take 2 μL (+) AuNPs solution and ingest it into the test cotton swab, add 2 μL of color developing solution dropwise, and break the test cotton swab. The ingested solution in the cotton swab reacts with the air pressure, so that the solution falls into the lower end of the cotton swab. , place the lower end of the cotton swab in the detection solution H ₂ O ₂ , take the cotton swab out of the H ₂ O ₂ , take standard solutions of uric acid of different concentrations, and place them in the standard solutions of uric acid of different concentrations. In the standard solution with high uric acid, the test cotton swab turns blue, and when the test cotton swab is placed in the standard solution with low uric acid, the test cotton swab turns white.

In this embodiment, the carbon-dotted gold nanometers encounter hydrogen peroxide to generate hydroxide, and the carbon-dotted gold nanometers react with 3,3',5,5'-tetramethylbenzidine, and transform into non- After the steps of coloring or blue 3,3',5,5'-tetramethylbenzidine include:

The colorless 3,3',5,5'-tetramethylbenzidine is uric acid without excessive reaction, and the blue 3,3',5,5'-tetramethylbenzidine is uric acid overreaction.

In this embodiment,

Experimental process: take the methanol solution of TMB with a concentration of 0.02 mol/L and the aqueous H ₂ O ₂ solution of 8.82 mol/L in a volume ratio of 5:1 to be used as the color developing solution. Take 2 μL (+) AuNPs solution and ingest it into the test cotton swab, add 2 μL of color developing solution dropwise, and break the test cotton swab. The ingested solution in the cotton swab reacts with the air pressure, so that the solution falls into the lower end of the cotton swab. , place the lower end of the cotton swab in the detection solution H ₂ O ₂ , take the cotton swab out of the H ₂ O ₂ , take standard solutions of uric acid of different concentrations, and place them in the standard solutions of uric acid of different concentrations. In the standard solution with high uric acid, the test cotton swab turns blue, and when the test cotton swab is placed in the standard solution with low uric acid, the test cotton swab turns white.

In this embodiment, the second cotton swab to be tested is placed in a preset uric acid detection kit to react with the urine of the corresponding patient to obtain a test cotton swab with uric acid content in step S3, further comprising: :

3,3',5,5'-tetramethylbenzidine was used as a chromogenic agent to react with the urine of the corresponding patient.

In this embodiment,

Experimental materials: In an environment without air pressure, take 3,3',5,5'-tetramethylbenzidine, drop 2 μL of the color developing solution into the ingestion test cotton swab, break the test cotton swab, and the cotton The ingested solution in the stick reacts with the air pressure, so that the solution falls into the lower end of the cotton swab, the lower end of the cotton swab is placed in the detection solution _H2O2 , the cotton _swab is _taken out from the _H2O2 , and different concentrations of The uric acid standard solution was placed in the uric acid standard solution of different concentrations. It was found that the test cotton swab was placed in the standard solution with high uric acid, and the test cotton swab turned blue. The test cotton swab was placed in the standard solution with low uric acid, and the test cotton swab It turns white; because 3,3',5,5'-tetramethylbenzidine is used as the color developer, the color change of the lower end of the cotton swab is too fast, and the experiment time that needs to wait is too long, resulting in the results obtained in the experiment Not completely sure, 3,3',5,5'-tetramethylbenzidine needs to be reconciled, but it can still effectively improve the experimental efficiency.

In this embodiment, the preparation steps of 3,3',5,5'-tetramethylbenzidine include:

Experimental materials: 2,6-dimethylaniline, absolute ethanol, hydrogen peroxide, deionized water solution, oxidant, ethanol;

Implementation process: add the undegraded 2,6-dimethylaniline into absolute ethanol, add the pre-prepared deionized aqueous solution with hydrogen peroxide solution to the absolute ethanol, add the oxidant dropwise, and stir until the dropwise addition is completed. The solid is separated out, and the solid is suction filtered, washed with water and ethanol, and dried in the air to obtain degraded 2,6-dimethylaniline; the degraded 2,6-dimethylaniline is added to the dissolved chlorinated In the aqueous solution of ammonium, add glacial acetic acid to stir, adjust the temperature to 15 ℃-20 ℃ during the stirring process, until the solid is separated out, carry out vacuum filtration on the solid, vacuum degree ≥ 0.08MPa, to obtain 3,3, 5,5-tetramethylbenzidine crude product; adding the 3,3,5,5-tetramethylbenzidine crude product to the pre-prepared methanol, warming up to 70°C and waiting for the reaction, until the concentrated reaction is generated The concentrated compound was obtained, the concentrated compound was added to ethanol, the temperature was continued to rise to 80° C., the temperature was stopped and filtered to obtain the finished product of 3,3,5,5-tetramethylbenzidine.

In this embodiment, the degraded 2,6-dimethylaniline is added to the aqueous solution dissolved in ammonium chloride, and then glacial acetic acid is added for stirring, and the temperature is adjusted to 15°C-20°C during the stirring process, Until the solid is separated out, the solid is subjected to vacuum filtration, and the degree of vacuum is ≥0.08MPa, in the step of obtaining the crude 3,3,5,5-tetramethylbenzidine product, further comprising:

Experimental materials: 3,3,5,5-tetramethylbenzidine crude product, benzyl chloride, dichloromethane, aqueous solution, sodium acetate methanol;

Experimental process: the solid is stirred and washed with water, then filtered with suction, repeated twice, and dried in an environment of 45-60 ° C for 2-3 hours to obtain an activated solid; the activated solid is dissolved in 2-5 times of dichloromethane , add 1-4 times of benzyl chloride, put the reaction solution in an aqueous solution at 30°C to 45°C, and take it out after 2-3 hours of reaction to obtain a crude product of activated solid; add the crude product of activated solid to a In a solution of 10% sodium acetate and methanol, stir and wash with methanol and then suction filtration, wash the crude product until the suction filtrate does not change color when exposed to water, and dry in an environment of 45-60° C. to obtain a fine product of activated crude.

In this embodiment, the first cotton swab to be tested is placed in a preset hydrogen peroxide solution for reaction to obtain a second cotton swab to be tested with hydroxide roots in step S2, the preset The preparation steps of the hydrogen peroxide solution include:

Experimental materials: positive and negative electrode plates, pure water (medium water), oxygen;

Experimental process: add medium water at the preset anode electrode end; pass reaction O ₂ into the preset cathode electrode end; connect the anode electrode end and the cathode electrode end with an external power supply to form an electrolysis path ; The medium water is decomposed into products O ₂ and H ⁺ on the end of the anode electrode after the electrolysis reaction, and the product O ₂ is discharged through the drain on the end of the anode electrode; The H ⁺ passes through The end of the cathode electrode plate reaches the cathode, and combines with the reaction O ₂ passed in to generate the product H ₂ O ₂ , and the product H ₂ O ₂ can be collected after being discharged through the exhaust port on the cathode end plate.

Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, and substitutions can be made in these embodiments without departing from the principle and spirit of the invention and modifications, the scope of the present invention is defined by the appended claims and their equivalents.

Claims (10)

1. a visual uric acid detection method based on nanomaterials, is characterized in that, comprises the following steps: S1: break apart the cotton swabs to be tested, make the cotton swabs to be tested react with the air pressure, and fall to the bottom end of the cotton swabs to obtain the first cotton swabs to be tested with positively charged gold nanoparticles on the surface; S2: the first cotton swab to be tested is placed in a preset hydrogen peroxide solution for reaction to obtain a second cotton swab to be tested with hydroxide radicals; S3: placing the second cotton swab to be tested in a preset uric acid detection kit to react with the urine of the corresponding patient to obtain a test cotton swab with uric acid content; S4: determine whether the test cotton swab changes to a preset color; S5: If yes, the uric acid of the patient undergoing the uric acid test is too high. 2. the visual uric acid detection method based on nanometer material according to claim 1, is characterized in that, described cotton swab to be tested is broken apart, and the air pressure in described cotton swab to be tested is reacted, and falls to cotton swab. At the bottom end of the rod, in step S1 of obtaining the first cotton swab to be tested with positively charged gold nanoparticles on the surface, the preparation process of the positively charged gold nanoparticles on the surface includes the following steps: Add chloroauric acid and ascorbic acid solution into double distilled water, stir while heating, until the color of the solution changes from initial yellow to red, then the nano-gold particle solution can be obtained; The carbon dots are added to the gold nanoparticle solution, and the gold nanoparticles with positive surface charges are obtained when the carbon dots completely wrap the gold nanoparticles. 3. the visual uric acid detection method based on nanometer material according to claim 2, is characterized in that, described chloroauric acid and ascorbic acid solution are added to double distilled water, stir while heating, until solution color is changed from initial In the step of changing from yellow to red, the nano-gold particle solution can be obtained, further comprising: The heating temperature is limited to the interval of 30-50°C. 4. The nanomaterial-based visual uric acid detection method according to claim 1, wherein the step S4 of judging whether the test cotton swab is changed to a preset color further comprises: The carbon-dotted gold nanometers encounter hydrogen peroxide to generate hydroxide, and the carbon-dotted gold nanometers react with 3,3',5,5'-tetramethylbenzidine and transform into colorless or blue 3,3 ',5,5'-Tetramethylbenzidine. 5. The visualized uric acid detection method based on nanomaterials according to claim 4, is characterized in that, described carbon dot gold nanometer encounters hydrogen peroxide to produce hydroxide radical, and described carbon dot gold nanometer and 3,3', 5,5'-Tetramethylbenzidine presents a reaction that transforms into colorless or blue 3,3',5,5'-Tetramethylbenzidine after steps including: The colorless 3,3',5,5'-tetramethylbenzidine is uric acid without excessive reaction, and the blue 3,3',5,5'-tetramethylbenzidine is uric acid overreaction. 6. The visualized uric acid detection method based on nanomaterials according to claim 1, wherein the second cotton swab to be tested is placed in a preset uric acid detection kit and performed with the urine of the corresponding patient. In the step S3 of obtaining the test cotton swab with uric acid content, the reaction also includes: 3,3',5,5'-tetramethylbenzidine was used as a chromogenic agent to react with the urine of the corresponding patient. 7. The visualized uric acid detection method based on nanomaterials according to claim 6, wherein the preparation step of the 3,3',5,5'-tetramethylbenzidine comprises: The undegraded 2,6-dimethylaniline is added to absolute ethanol, the pre-prepared deionized aqueous solution with hydrogen peroxide solution is added to the absolute ethanol, the oxidant is added dropwise, and after the dropwise addition is completed, the mixture is stirred until the solid is precipitated, The solid was filtered off with suction, washed with water and ethanol and air-dried to obtain 2,6-dimethylaniline degraded; The degraded 2,6-dimethylaniline is added to the aqueous solution in which ammonium chloride is dissolved, and then glacial acetic acid is added to stir, and the temperature is adjusted to 15° C.-20° C. during the stirring process until the solid is precipitated. The solid is vacuum filtered, and the degree of vacuum is greater than or equal to 0.08MPa to obtain the crude product of 3,3,5,5-tetramethylbenzidine; The 3,3,5,5-tetramethylbenzidine crude product was added to the pre-prepared methanol, and the temperature was raised to 70° C. and waited for the reaction, until the concentrated compound was obtained after the concentrated reaction, and the concentrated compound was obtained. Add to ethanol, continue to heat up to 80°C, stop the temperature rise and filter to obtain the finished product of 3,3,5,5-tetramethylbenzidine. 8. nanomaterial-based visualization uric acid detection method according to claim 7, is characterized in that, the described degraded 2,6-dimethylaniline is added to the aqueous solution that is dissolved in ammonium chloride, and then Add glacial acetic acid for stirring, adjust the temperature to 15 ℃-20 ℃ during the stirring process, until the solid is precipitated, carry out vacuum filtration on the solid, vacuum degree ≥ 0.08MPa, to obtain 3,3,5,5-tetramethyl In the step of base benzidine crude product, it also includes: The solid is stirred and washed with water, filtered with suction, repeated twice, and dried in an environment of 45-60° C. for 2-3 hours to obtain an activated solid; The activated solid was dissolved in 2-5 times of dichloromethane, 1-4 times of benzyl chloride was added, the reaction solution was placed in an aqueous solution at 30°C to 45°C, and taken out after reacting for 2-3 hours to obtain the Crude activated solid; The crude product of the activated solid was added to a solution with 10% sodium acetate methanol, stirred and washed with methanol and then suction filtered, washed the crude product until the suction filtrate did not change color when exposed to water, and dried at 45-60°C , to get the active bolded boutique. 9. The visualized uric acid detection method based on nanomaterials according to claim 1, characterized in that, the first cotton swab to be tested is placed in a preset hydrogen peroxide solution and reacted, so as to obtain products with hydroxide radicals. In step S2 of the second cotton swab to be tested, the preparation steps of the preset hydrogen peroxide solution include: Add medium water to the preset anode plate end; Feed reaction O ₂ at the preset cathode electrode end; Connecting the anode electrode plate end and the cathode electrode plate end with an external power source to form an electrolysis path; The medium water is decomposed into products O ₂ and H ⁺ on the end of the anode electric plate after electrolysis reaction, and the product O ₂ is discharged through the drain port on the end of the anode electric plate; The H ⁺ reaches the cathode through the cathode electrode plate end, and combines with the reaction O ₂ fed in to generate the product H ₂ O ₂ . After the product H ₂ O ₂ is discharged through the exhaust port on the cathode end plate, to collect. 10 . The visualized uric acid detection method based on nanomaterials according to claim 9 , wherein the electrolysis reaction temperature is set between 20° C. and 50° C. 11 .

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