Disclosure of Invention
In view of the above, the present invention aims to provide a silver source detection method based on nano-enzyme catalysis driving. The method provided by the invention is simple to operate and low in cost, and can be used for quickly and accurately detecting the content of silver ions or silver nanoparticles in a sample in real time.
In order to achieve the above object, the present invention provides the following technical solutions:
the invention provides application of platinum nanoparticles in silver source detection, wherein the platinum nanoparticles are obtained by reducing chloroplatinic acid with ascorbic acid, and the silver source comprises silver ions and/or silver nanoparticles.
The invention provides a silver source detection method based on nano enzyme catalysis driving, which comprises the following steps:
(1) mixing platinum nanoparticles with an excess of H2O2Mixing the solutions to perform catalytic decomposition reaction, and discharging the generated O2Converted to an equal volume of liquid and the mass m of discharged liquid recorded over a fixed time t1The platinum nanoparticles are obtained by reducing chloroplatinic acid with ascorbic acid, and the fixed time t is 28-32 min;
(2) mixing platinum nanoparticles with excess H2O2Mixing the solution with the sample solution to be detected to perform catalytic decomposition reaction, and discharging the generated O2Converting into liquid with equal volume, and recording the mass m of discharged liquid within the same fixed time t2(ii) a Mass of the platinum nanoparticles, H2O2The concentration and volume of the solution are the same as those in the step (1);
(3) according to the standard curve and m1And m2Obtaining the content of the silver source in the sample solution to be detected according to the difference value delta m; the standard curve is a linear relation curve of the concentration of the silver source and the delta m;
the silver source is silver ions or silver nanoparticles;
there is no time sequence restriction between the step (1) and the step (2).
Preferably, the preparation method of the platinum nanoparticles comprises the following steps:
mixing chloroplatinic acid, ascorbic acid and water, and carrying out hydrothermal reduction reaction to obtain the platinum nanoparticles.
Preferably, the molar ratio of the chloroplatinic acid to the ascorbic acid is 1: 3-4.
Preferably, the temperature of the hydrothermal reduction reaction is 60-80 ℃ and the time is 1-1.5 h.
Preferably, H in the step (1) and the step (2)2O2The concentration of the solution is 8-12 mol/L;
the platinum nanoparticles are added in the form of aqueous dispersion, the concentration of the aqueous dispersion of the platinum nanoparticles is 0.01-0.1 mmol/L, and the water content of the platinum nanoparticles isPowder and H2O2The volume ratio of the solution is 1:35 to 50.
Preferably, the sample solution to be tested in the step (2) is mixed with H2O2The volume ratio of the solution is 1: 35-50.
Preferably, the steps (1) and (2) are carried out at 20-35 ℃.
The invention provides a silver source detection device based on nano-enzyme catalysis driving, which comprises a detection container 1, wherein the detection container 1 is used for containing liquid which does not react with oxygen; the detection container 1 can be sealed;
a liquid discharge pipe 2 which can communicate the inside and the outside of the detection container 1, wherein one end of the liquid discharge pipe 2 is positioned below the liquid level in the detection container 1 when in use, and the other end is communicated with a collecting device 4 outside the detection container 1;
an open reaction vessel 3 positioned inside the detection vessel 1 and placed on the base 5; when in use, the open position of the open reaction container 3 is higher than the liquid level; during detection, platinum nanoparticles are filled in the open reaction container 3, and the platinum nanoparticles are obtained by reducing chloroplatinic acid with ascorbic acid;
and a collecting device 4 located outside the detection container 1 and communicating with the drain pipe 2.
Preferably, the liquid which does not react with oxygen is water, 0.01-0.05 mmol/L HCl solution and 0.01-0.05 mmol/L H2SO4One or more of the solution and 0.1-1 mmol/LNaOH solution.
The invention provides a silver source detection method based on nano-enzyme catalysis driving, platinum nano-particles (AA-PtNPs) obtained by reducing ascorbic acid are used as a nano-enzyme catalyst, and the enzyme-like activity of the AA-PtNPs can catalyze hydrogen peroxide to decompose to generate water and oxygen; since AA-PtNPs have better enzyme-like activity and chemical stability, the liquid is discharged in a certain amount within a fixed time after excessive hydrogen peroxide is added. When the target object Ag exists in the sample solution to be detected+Or silver nanoparticles, Ag+Or silver nanoparticles can be combined on the surface of the AA-PtNPs and occupy partial active sites on the surface of the AA-PtNPs, so that the enzymatic activity of the AA-PtNPs is obviously reduced, and then the silver nanoparticles are addedThe amount of liquid discharged in the same fixed time period is significantly reduced after the same concentration and volume of hydrogen peroxide. According to the method, the content of silver ions or silver nanoparticles in the solution of the sample to be detected is calculated according to the standard curve by calculating the difference of the quality of the two times of liquid drainage and the linear relation between the variable quantity and the concentration of Ag. In the invention, the platinum nanoparticles obtained by reducing chloroplatinic acid with ascorbic acid have negative charges on the surface, silver ions have positive charges, and the silver ions are easier to enrich around the platinum nanoparticles under the action of the positive and negative charges, so that the detection accuracy can be improved. In the invention, the signal output mode is to weigh the mass of the discharged liquid, thereby avoiding the limitation of the need of precise instruments and equipment and professional operators for analysis and detection. Meanwhile, AA-PtNPs are on Ag+Or the silver nanoparticles have good selectivity, and can avoid the interference of other impurity ions, thereby ensuring the accuracy of the measurement result.
The invention provides a silver source detection device based on nano-enzyme catalysis driving, which comprises a detection container 1 filled with liquid which does not react with oxygen, an open reaction container 3 positioned in the detection container 1 and placed on a base 5, and a collection device 4 positioned outside the detection container 1 and connected with a liquid discharge pipe 2. The device provided by the invention can simply, conveniently and quickly detect the content of silver ions or silver nanoparticles in a sample in real time, has a simple structure and low cost, and is suitable for popularization and use.
Detailed Description
The invention provides application of platinum nanoparticles in silver source detection, wherein the platinum nanoparticles are obtained by reducing chloroplatinic acid with ascorbic acid, and the silver source comprises silver ions and/or silver nanoparticles.
The invention provides a silver source detection method based on nano enzyme catalysis driving, which comprises the following steps:
(1) mixing platinum nanoparticles with an excess of H2O2Mixing the solutions to perform catalytic decomposition reaction, and discharging the generated O2Converted to an equal volume of liquid and the mass m of discharged liquid recorded over a fixed time t1The platinum nanoparticles are obtained by reducing chloroplatinic acid with ascorbic acid, and the fixed time t is 30 min;
(2) mixing platinum nanoparticles with excess H2O2Mixing the solution with the sample solution to be detected to perform catalytic decomposition reaction, and discharging the generated O2Converting into liquid with equal volume, and recording the mass m of discharged liquid within the same fixed time t2(ii) a Mass of the platinum nanoparticles, H2O2The concentration and volume of the solution are the same as those in the step (1);
(3) according to the standard curve and m1And m2Obtaining the content of the silver source in the sample solution to be detected according to the difference value delta m; the standard curve is a linear relation curve of the concentration of the silver source and the delta m;
the silver source is silver ions or silver nanoparticles;
there is no time sequence restriction between the step (1) and the step (2).
The invention combines platinum nanoparticles and excess H2O2Mixing the solutions to perform catalytic decomposition reaction, and discharging the generated O2Converted to an equal volume of liquid and the mass m of discharged liquid recorded over a fixed time t1The platinum nanoparticles are obtained by reducing chloroplatinic acid with ascorbic acid, and the fixed time t is 30 min. The method for preparing platinum nanoparticles in the present invention preferably comprises the steps of:
mixing chloroplatinic acid, ascorbic acid and water, and carrying out hydrothermal reaction to obtain the platinum nanoparticles.
In the invention, the molar ratio of the chloroplatinic acid to the ascorbic acid is preferably 1: 3-4, and more preferably 1: 3.5; in the invention, the temperature of the hydrothermal reaction is preferably 60-80 ℃, more preferably 60-70 ℃, and the time is preferably 1-1.5 h.
After the hydrothermal reaction, the present invention preferably performs a post-treatment on the obtained hydrothermal reaction solution, and the post-treatment preferably includes the following steps:
and carrying out centrifugal washing on the hydrothermal reaction liquid to obtain the platinum nano-particles.
In the invention, the speed of centrifugal washing is preferably 15000r/min, and the time is preferably 10-15 min; the detergent for centrifugal washing is preferably water, the temperature of the centrifugal washing is preferably 4 ℃, and the number of times of the centrifugal washing is preferably 2.
In the present invention, said H2O2The concentration of the solution is preferably 10 mol/L; the platinum nanoparticles are added in the form of an aqueous dispersion, and the concentration of the aqueous dispersion of the platinum nanoparticles is preferably 0.01-0.1 mmol/L, and more preferably 0.05 mmol/L; of the aqueous dispersion of platinum nanoparticles with H2O2The volume ratio of the solution is preferably 1: 30-50, and more preferably 1: 40. In the invention, the fixed time t is preferably 28-32 min, and more preferably 30 min.
To obtain m1Then, the invention adds platinum nanoparticles and excess H2O2Mixing the solution with the sample solution to be detected to perform catalytic decomposition reaction, and discharging the generated O2Converting into liquid with equal volume, and recording the mass m of discharged liquid within the same fixed time t2(ii) a Mass of the platinum nanoparticles, H2O2The concentration and volume of the solution are the same as in step (1).
In the invention, when the solution of the sample to be detected contains silver ions, the content of the silver ions in the sample to be detected is preferably 0-0.3 mu M; when the sample to be detected contains silver nanoparticles, the content of the silver nanoparticles in the sample to be detected is preferably 0-350 pM.
To obtain m2Then, the invention is based on the standard curve and m1And m2Obtaining the content of silver ions or silver nanoparticles in the solution of the sample to be detected; the standard curve is a linear relation curve of the concentration of the silver source in the silver source solution and the delta m.
In the present invention, when the standard curve is a linear relationship between silver ion concentration and Δ m, the method for drawing the standard curve preferably includes the steps of:
(1) providing a silver ion standard solution;
(2) the method is adopted to obtain the Delta m of the silver ion standard solution, the concentration of the silver ion standard solution is used as a horizontal coordinate, and the Delta m is used as a vertical coordinate to draw a standard curve.
In the present invention, the solute in the silver ion standard solution is preferably silver nitrate; the concentration of the silver ion standard solution is preferably 0nM, 5nM, 10nM, 25nM, 50nM, 100nM, 175nM, 250nM, 500nM, 1. mu.M, 2.5. mu.M, 3.5. mu.M and 5. mu.M. As a specific example of the present invention, the standard curve of the silver ion concentration and Δ m is-3.2827C +1.8318, R20.9984; wherein C is silver ion concentration, μ M.
In the present invention, when the standard curve is a linear relationship between silver nanoparticle concentration and Δ m, the method for drawing the standard curve preferably includes the steps of:
(1) providing a standard solution of silver nanoparticles;
(2) the method is adopted to obtain the Delta m of the silver nanoparticle standard solution, the concentration of the silver nanoparticle standard solution is used as a horizontal coordinate, and the Delta m is used as a vertical coordinate to draw a standard curve.
In the invention, the particle size of the silver nanoparticles is preferably 10-100 nm, and as a specific embodiment of the invention, the particle size of the silver nanoparticles is 30-50 nm; the concentration of the silver nanoparticle standard solution is preferably 0pM, 10pM, 20pM, 50pM, 100pM, 150pM, 200pM, 300pM and 500 pM. As a specific example of the present invention, the standard curve of the silver nanoparticle concentration and Δ m is-0.0055C +1.8141, R20.9977; wherein C isIs the silver nanoparticle concentration, pM.
The invention provides a silver ion or silver nanoparticle detection device based on nano-enzyme catalysis driving, which comprises a detection container 1, wherein the detection container 1 is used for containing liquid which does not react with oxygen; the detection container 1 can be sealed;
a liquid discharge pipe 2 which can communicate the inside and the outside of the detection container 1, wherein one end of the liquid discharge pipe 2 is positioned below the liquid level in the detection container 1 when in use, and the other end is communicated with a collecting device 4 outside the detection container 1;
an open reaction vessel 3 positioned inside the detection vessel 1 and placed on the base 5; when in use, the open position of the open reaction container 3 is higher than the liquid level; during detection, platinum nanoparticles are filled in the open reaction container 3, and the platinum nanoparticles are obtained by reducing chloroplatinic acid with ascorbic acid;
and a collecting device 4 located outside the detection container 1 and communicating with the drain pipe 2.
The invention provides a device for detecting silver ions or silver nanoparticles based on nano-enzyme catalysis driving, which comprises a detection container 1. In the present invention, the detection container 1 is used for containing liquid which does not react with oxygen; the detection container 1 can be hermetically sealed. The present invention does not require any particular kind of detection container 1, and a sealable container known to those skilled in the art may be used. As an embodiment of the present invention, the detection container 1 is preferably a glass bottle with a bottle stopper. The invention has no special requirements on the size and specification of the detection container 1, and can be designed correspondingly according to the actual situation.
In the invention, the liquid which does not react with oxygen is preferably water, 0.01-0.05 mmol/L HCl solution, 0.01-0.05 mmol/L H2SO4One or more of the solution and 0.1-1 mmol/L NaOH solution.
The silver ion or silver nanoparticle detection device based on nano-enzyme catalysis driving comprises a liquid discharge pipe 2 capable of communicating the inside and the outside of a detection container 1, wherein one end of the liquid discharge pipe 2 is positioned below the liquid level when the device is used, and the other end of the liquid discharge pipe is communicated with the outside of the detection container 1. The invention has no special requirements on the type and the material of the liquid discharge pipe 2, can realize the liquid discharge function and does not react with liquid.
The invention provides a silver ion or silver nanoparticle detection device based on nano-enzyme catalysis driving, which comprises an open reaction container 3, a detection container 1 and a base 5, wherein the open reaction container is positioned inside the detection container; the open position of the open reaction vessel 3 is higher than the liquid level. The present invention has no special requirements for the kind of the open reaction vessel 3, and it is sufficient to use an open vessel known to those skilled in the art, such as a beaker. The invention has no special requirements on the size and specification of the open reaction vessel 3, and can be designed correspondingly according to the actual situation.
In the present invention, in the detection, platinum nanoparticles obtained by reducing chloroplatinic acid with ascorbic acid are filled in the open reaction vessel 3.
The device for detecting silver ions or silver nanoparticles based on the catalytic driving of the nanoenzyme provided by the invention also preferably comprises a base 5 positioned at the bottom in the detection container 1, wherein the base 5 is used for placing the open reaction container 3 to increase the height of the open reaction container 3 in the detection container 1.
The invention provides a device for detecting silver ions or silver nanoparticles based on nano-enzyme catalytic driving, which comprises a collecting device 4 which is positioned outside a detection container 1 and connected with a liquid discharge pipe 2. The invention does not require a special device for the handset, and uses a collection container known to those skilled in the art.
The structure schematic diagram of the silver ion or silver nanoparticle detection device based on the nano-enzyme catalytic driving is shown in figure 1, wherein 1 is a detection container, 2 is a liquid discharge pipe, 3 is an open reaction container, 4 is a collection device, and 5 is a base.
The following examples are provided to illustrate the method for detecting silver source based on nanoenzyme catalytic driving of the present invention in detail, but they should not be construed as limiting the scope of the present invention.
Example 1
The preparation method of the silver source detection device based on the nano-enzyme catalysis driving comprises the following steps:
(1) a small hole of 1mm is drilled on the glass bottle by a drilling machine, and the position of the small hole is 3cm away from the bottom of the glass bottle and is higher than the upper end of the open reaction vessel in the glass bottle. A glass capillary tube having a length of 5cm, an inner diameter of 0.9mm and an outer diameter of 1.1mm was cut out, and the ratio of the length of the glass capillary tube to the diameter of the glass capillary tube was 3: and 2, marking by using an oil pen, horizontally holding one end of the glass capillary tube, slightly contacting by using a tiny open fire, slightly burning, and immediately stopping burning after an included angle of 90 degrees is formed at the left end and the right end of the marked position of the glass capillary tube. Inserting one end of the manufactured glass capillary tube with the bending angle of 90 degrees by 3cm into a small hole of the glass bottle body, and enabling the end to be parallel to the bottle body; one end of 2cm is vertical to the bottle body. And then, adhering the contact point of the glass capillary tube and the bottle body by using 10 mu L of 502 glue, after the adhesion is stable, dropwise adding a mixture of common glue and 502 glue to block the rest position of the hole, and drying for 3 hours at normal temperature.
(2) A section of rigid material with the height of 1cm and the length and the width of 0.2cm is cut out to manufacture a base, and then a tube cover of a 2mL centrifuge tube is cut out, and all the materials except a central groove of the cover are cut out. Vertically placing the base, adhering the cut centrifugal tube cover to the upper end of the base by using glue, wherein one surface of the groove faces upwards; after glue is coated on the lower end of the base, the base is vertically placed into a glass bottle, the lower end of the base is vertically adhered to the bottom of the glass bottle, and the base is dried for 3 hours at normal temperature.
(3) The sealing film is wound on the bottle mouth of the glass bottle for two circles, so that the sealing property of the glass bottle is ensured.
(4) Verifying the tightness of the experimental instrument, injecting 3mL of ultrapure water solution into the prepared glass bottle, and screwing down the cover of the glass bottle to extrude oxygen in the glass bottle to increase the air pressure. At this time, a small amount of the aqueous solution was discharged from the tube, and the tube was filled with the aqueous solution for a long time after the air pressure in the bottle was stabilized, so that the suck-back phenomenon was not caused, indicating that the sealing property of the glass bottle was good.
Example 2
Preparation of platinum nanoparticles:
(1) adding 2mL of chloroplatinic acid hexahydrate with the concentration of 2mmol/L and 1mL of ultrapure water into a reaction vessel, heating to 60 ℃ under magnetic stirring, adding 1.5mL of ascorbic acid with the concentration of 10mmol/L, heating and stirring for 1 hour at 60 ℃, wherein the solution is changed from light yellow to brown and then is changed into dark brown in the hydrothermal reaction process;
(2) after the hydrothermal reaction is finished, the reaction liquid is cooled to room temperature, and is centrifugally washed twice at 15000r/min to obtain the platinum nano-particles AA-PtNPs, and the obtained AA-PtNPs are re-dispersed in water and stored at 4 ℃.
Example 3
Standard curve of silver ion concentration versus Δ m:
(1) 5. mu.L of 0.05mmol/L AA-PtNPs and 200. mu.L of 10mol/L H were added to the open reaction vessel of example 12O2The solution, closed glass bottle, record the mass m of the discharged liquid within 30min1;
(2) Adding AA-PtNPs and H into the open reaction vessel again2O2Solutions and silver ion standard solutions of different concentrations (0nM, 5nM, 10nM, 25nM, 50nM, 100nM, 175nM, 250nM, 500nM, 1. mu.M, 2.5. mu.M, 3.5. mu.M, 5. mu.M and 10. mu.M), closed test vessel 1, recording the mass M of discharged liquid within 30min2The AA-PtNPs and H2O2The amount of the solution added was the same as in step (1). The curve of the change of silver ion concentration with Δ m is shown in fig. 2. As can be seen from FIG. 2, the silver ion concentration and Δ M are linearly and negatively correlated in the range of 0 to 0.3 μ M, and a standard curve is plotted with the silver ion standard solution concentration as abscissa and Δ M as ordinate in the range of 0 to 0.3 μ M, and the obtained result is shown in FIG. 3. Wherein, the standard curve of the silver ion concentration and the delta m is-3.2827C +1.8318, R20.9984; c is silver ion concentration, mu M, and C is between 0 and 0.3 mu M.
Standard curve of silver nanoparticle concentration versus Δ m:
(1) 5 μ L of 0.05mmol/L AA-Pt NPs and 200 μ L of 10mol/L H were added to the open reaction vessel of example 12O2The solution, closed glass bottle, record the mass m of the discharged liquid within 30min1;
(2) Adding AA-PtNPs and H into the open reaction vessel again2O2Solutions and silver nanoparticle standard solutions of different concentrations (0 p)M, 10pM, 20pM, 50pM, 100pM, 150pM, 200pM, 300pM, 500pM, 1000pM and 1500pM), the detection vessel 1 was closed, and the mass M of the discharged liquid within 30min was recorded2The AA-PtNPs and H2O2The amount of the solution added was the same as in step (1). The variation of silver nanoparticle concentration versus Δ m is shown in fig. 4. It can be seen from fig. 4 that the silver ion concentration and Δ m are linearly and negatively correlated in the range of 0 to 350pM, and a standard curve is drawn with the concentration of the silver nanoparticle standard solution as the abscissa and Δ m as the ordinate in the range of 0 to 350pM, and the obtained result is shown in fig. 5. Wherein the standard curve of the silver nanoparticle concentration and the delta m is-0.0055C +1.8141, R20.9977; where C is the silver nanoparticle concentration, pM.
Example 4
Silver ion (Ag) in tap water+) The labeling recovery experiment of (1):
(1) 5. mu.L of 0.05mmol/L AA-PtNPs and 200. mu.L of 10mol/L H were added to the open reaction vessel of example 12O2The solution, closed glass bottle, record the mass m of the discharged liquid within 30min1;
(2) Standing tap water solution at room temperature for 10min, and preparing Ag (5nM, 50nM, 100nM) with tap water solution+。
(3) Taking 50 mu L of Ag in the step (2)+The solution was mixed with the same volume of 0.1mmol/L AA-Pt NPs and incubated for 5 min.
(4) Transferring 5. mu.L of the mixed sample obtained in the step (3) into a reaction vessel, and adding 200. mu.L of 10mol/L H2O2Sealing the glass bottle, recording the mass m of the discharged liquid within 30min2;
(5) The concentration of silver ions was calculated by substituting Δ m into the standard curve of silver ion concentration and Δ m in example 3. The recovery and RSD were calculated by the ratio of the actual calculated concentration to the theoretical concentration. The results obtained are shown in table 1.
TABLE 1 experimental results of silver ion recovery from tap water
Example 5
Spiking recovery experiment of silver nanoparticles (AgNPs) in tap water:
(1) 5. mu.L of 0.05mmol/L AA-PtNPs and 200. mu.L of 10mol/L H were added to the open reaction vessel of example 12O2The solution, closed glass bottle, record the mass m of the discharged liquid within 30min1;
(2) The tap water solution is taken and placed for 10min at room temperature, and AgNPs with different concentrations (10pM, 100pM and 1000pM) are prepared by the tap water solution.
(3) Adding 1 mu L of 10mol/L H to the AgNPs solution in the step (2)2O2And when the mixture is mixed for 1min, the AgNPs are all converted into Ag+。
(4) And (3) adding 50 mu L of AgNPs solution in the step (3) into the same volume of 0.1mmol/L platinum nanoparticle solution, and mixing and incubating for 5 min.
(5) Transferring 5. mu.L of the mixed sample obtained in the step (4) into a reaction vessel, and adding 200. mu.L of 10mol/L H2O2Sealing the glass bottle, recording the mass m of the discharged liquid within 30min2;
(6) The concentration of silver nanoparticles was calculated by substituting Δ m into the standard curve of silver nanoparticle concentration and Δ m in example 3. The recovery and RSD were calculated by the ratio of the actual calculated concentration to the theoretical concentration. The results obtained are shown in Table 2.
TABLE 2 experimental data for the spiking recovery of silver nanoparticles from tap water
Example 6
(1) 5. mu.L of 0.05mmol/L AA-PtNPs and 200. mu.L of 10mol/L H were added to the open reaction vessel of example 12O2The solution, closed glass bottle, record the mass m of the discharged liquid within 30min1;
(2) Re-adding the same amount of AA-PtNPs and H into the open reaction vessel2O2Adding silver ion standard solution with concentration of 500nM into the solutionAnd different interfering ion solutions, the interfering ions being sodium ions (Na) respectively+) Potassium ion (K)+) Magnesium ion (Mg)2+) Manganese ion (Mn)2+) Zinc ion (Zn)2+) Cadmium ion (Cd)2+) Ferrous ion (Fe)2+) Iron ion (Fe)3+) Chromium ion (Cr)3+) Lithium ion (Li)+) Acetate ion (Ac)-) Fluorine ion (F)-) Bromine ion (Br)-) Barium ion (Ba)2+) Ammonium ion (NH)4 +) Nickel ion (Ni)2+) Chloride ion (Cl)-) Sulfate ion (SO)4 2-) Nitrate ion (NO)3 -) Carbonate ion (CO)3 2-) Sulfite ion (SO)3 2-) The concentration of interfering ions was 5. mu.M, and the mass M of discharged liquid within 30min was recorded2;
(3) Calculate m2And m1The results are shown in FIG. 6. As can be seen from FIG. 6, the quality of the second drainage was significantly reduced in the presence of 500nM of the silver ion standard solution, m of which2/m140.5%, and in the presence of other interfering ions, the quality of the second drainage did not significantly decrease, its m2/m1All are about 100%, which shows that AA-PtNPs are applied to Ag+Has good selectivity and can avoid the interference of other impurity ions.
The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.