Mercury ion detection method and device, and preparation method of gold nanoraman enhancer

Abstract

The application discloses a mercury ion detection method and device and a preparation method of a nano-gold Raman enhancer, and is used for improving the detection accuracy of heavy metal mercury ions. The mercury ion detection method comprises the following steps: preparing a nano-gold Raman enhancer by using a chloroauric acid solution, a sodium citrate solution and a thiuram solution; adding the nano-gold Raman enhancer into a mercury ion reference solution; performing Raman spectrum detection on the mixture to generate a spectrum graph; determining a target characteristic peak from the spectrum graph as a discrimination basis for enhancing Raman scattering spectrum detection of mercury ions, and determining that the mercury ion concentration and the intensity of the characteristic peak are in a positive correlation relationship, the mercury ion reference solution is a solution with a known mercury ion concentration; adding the nano-gold Raman enhancer into a sample solution to be detected; performing Raman spectrum detection on the mixture, and calculating the mercury ion concentration in the sample solution to be detected according to the peak area of the known characteristic peak.

Description

TECHNICAL FIELD

[0001] Embodiments of the present application relate to the field of mercury ion detection, and particularly relate to a mercury ion detection method and device, and a preparation method of a gold nanometer Raman enhancer. BACKGROUND

[0002] Mercury is a metal element, commonly known as mercury, English name Mercury, chemical element symbol Hg, and group IIB metal in the periodic table. Mercury, mercury vapor, mercury compounds and their solutions are mostly toxic (chronic). The damage to the human body is mostly chronic neurotoxicity, and acute poisoning is a minority. The toxicity of mercury and its compounds will be different due to different ways of inhalation or ingestion or different amounts. For example, the lethal dose of mercuric chloride (HgCL2) is 0.3g, and the most dangerous mercury organic compound is dimethyl mercury [(CH3)2Hg], and only a few microliters of dimethyl mercury contact on the skin can be fatal. Minamata disease, i.e. methyl mercury poisoning, is also a very serious mercury poisoning disease. On October 10, 2013, Japan signed the Minamata Convention first, aiming to reduce mercury (commonly known as mercury) emissions worldwide to reduce the harm of mercury to the environment and human health.

[0003] Currently, for different substrates and different forms of mercury compounds and mercury ions, the current national standard method has atomic fluorescence method, gas chromatography, cold atomic absorption spectrophotometry, inductively coupled plasma mass spectrometry, and the method detection limit is distributed in 1-100ppb.

[0004] In Chinese patent CN110954526A, a method is disclosed, which utilizes thiourea to complex with mercury ions in the water sample to be measured, adds gold nanoparticle sol or silver nanoparticle sol and inorganic salt solution containing F- or Cl-, uses a Raman spectrometer to detect the characteristic Raman peak of the mixed solution to be measured at 1044cm-1, and qualitatively and quantitatively detects the mercury ions in the water sample to be measured according to the peak position and peak intensity. However, the characteristic peak of this scheme is single, and false positive results are easily produced in the detection process.

[0005] In Chinese patent CN104697980A, a method is disclosed, which uses a SERS active chip modified by sodium dimethyl dithiocarbamate for quantitative detection of mercury ions. According to the characteristics of the change of the SERS fingerprint information of sodium dimethyl dithiocarbamate after combining with mercury ions, the mercury ions are quantitatively analyzed. The change of the fingerprint information of sodium dimethyl dithiocarbamate in this method is actually a small displacement of the peak position near 1375cm-1, which is difficult to accurately distinguish the peak displacement of mercury ions on most instruments, and the random error has a great influence on the result.

[0006] In summary, the existing mercury ion detection methods are prone to produce false detection results, which reduces the detection accuracy of heavy metal mercury ions. Summary of the Invention

[0007] This application discloses a method and apparatus for detecting mercury ions, and a method for preparing a nano-gold Raman enhancer, which are used to improve the detection accuracy of heavy metal mercury ions.

[0008] The first aspect of this application provides a Raman detection method for mercury ions, comprising:

[0009] A nano-gold Raman enhancer was prepared using chloroauric acid solution, sodium citrate solution and thiuram solution, wherein the nano-gold sol in the nano-gold enhancer contains one or more of spherical gold nanoparticles, ellipsoidal gold nanoparticles, polygonal gold nanoparticles, rod-shaped gold nanoparticles and star-shaped gold nanoparticles.

[0010] Add the nano-gold Raman enhancer to the mercury ion reference solution;

[0011] The mixture was subjected to Raman spectroscopy to generate a spectrum;

[0012] The target characteristic peaks in the spectrum are identified as the criteria for detecting mercury ions using enhanced Raman scattering spectroscopy, and it is determined that there is a positive correlation between the concentration of mercury ions and the intensity of the characteristic peaks. The mercury ion reference solution is a solution with a known concentration of mercury ions.

[0013] Add the nano-gold Raman enhancer to the sample solution;

[0014] The mixture was subjected to Raman spectroscopy, and the concentration of mercury ions in the sample solution was calculated based on the peak areas of the known characteristic peaks.

[0015] Optionally, the nano-gold Raman enhancer is added to the mercury ion reference solution, including:

[0016] The nano-gold Raman enhancer and mercury ion reference solution were mixed at a volume ratio of 0.1-10:1, and then an agglomerating agent was added. The mixture was allowed to stand for a preset time. The agglomerating agent contained metal salt ions.

[0017] Adding the nano-gold Raman enhancer to the sample solution includes:

[0018] The nano-gold Raman enhancer and the sample solution to be tested are mixed at a volume ratio of 0.1-10:1, and then an agglomerating agent is added. The mixture is then allowed to stand for a preset time. The agglomerating agent contains metal salt ions.

[0019] A second aspect of this application provides a method for preparing a nano-gold Raman enhancer, comprising:

[0020] Obtain a chloroauric acid solution of a preset concentration and heat the chloroauric acid solution to boiling.

[0021] Add sodium citrate solution as a reducing agent to the chloroauric acid solution and stir.

[0022] The stirred solution was cooled to generate nano-gold sol;

[0023] Add a thiuram solution of a predetermined concentration to the gold nanoparticle sol and mix thoroughly.

[0024] The mixed solution was incubated at room temperature for a preset time period;

[0025] The incubated mixed solution is then concentrated by centrifugation.

[0026] A reconstitution solution was added to the mixed solution after centrifugation and concentration to reconstitute it, thereby generating a nano-gold Raman enhancer.

[0027] Optionally, a chloroauric acid solution of a preset concentration is obtained, and the chloroauric acid solution is heated to boiling, including:

[0028] Obtain an Aml chloroauric acid solution with a mass fraction of 0.01%, and heat the chloroauric acid solution to boiling.

[0029] Add sodium citrate solution as a reducing agent to chloroauric acid solution and stir, including:

[0030] Add B ml of 1% sodium citrate solution as a reducing agent to the chloroauric acid solution and stir. The ratio of A to B is 100:1.

[0031] Optionally, the incubated mixture may be concentrated by centrifugation, including:

[0032] The incubated mixed solution was centrifuged and concentrated to produce X ml of concentrated solution;

[0033] A reconstitution solution was added to the centrifuged and concentrated mixed solution for reconstitution treatment to generate a nano-gold Raman enhancer, including:

[0034] Add Y ml of reconstituted solution to the mixed solution after centrifugation and concentration to reconstitute and generate nano-gold Raman enhancer, where X:Y is 1-20:10-200.

[0035] Optionally, the reconstitution solution can be ultrapure water, sodium citrate solution, CTAB solution, CTAC solution, ethylene glycol solution, PvP solution, PEG solution, or PBS solution.

[0036] Optionally, a thiuram solution of a preset concentration is added to the gold nanoparticle sol and mixed thoroughly, including:

[0037] Add 0.01mM-1mM thiuram solution to the gold nanoparticle sol and mix thoroughly.

[0038] Optionally, the mixed solution is incubated at room temperature for a preset time period, including:

[0039] The mixed solution was incubated at a temperature of 0-60 degrees Celsius for 72 hours.

[0040] A third aspect of this application provides a Raman detection device for mercury ions, comprising:

[0041] The preparation unit is used to prepare a gold nanoparticle Raman enhancer using chloroauric acid solution, sodium citrate solution and thiuram solution, wherein the gold nanoparticle Raman enhancer contains one or more of the following: spherical gold nanoparticles, ellipsoidal gold nanoparticles, polygonal gold nanoparticles, rod-shaped gold nanoparticles and star-shaped gold nanoparticles.

[0042] The first mixing unit is used to add the nano-gold Raman enhancer to the mercury ion reference solution;

[0043] The first detection unit is used to perform Raman spectroscopy detection on the mixture and generate a spectrum.

[0044] The determination unit is used to identify the target characteristic peak from the spectrum as the discrimination criterion for enhanced Raman scattering spectroscopy detection of mercury ions, and to determine that the concentration of mercury ions is positively correlated with the intensity of the characteristic peak. The mercury ion reference solution is a solution with a known concentration of mercury ions.

[0045] The second mixing unit is used to add the nano-gold Raman enhancer to the sample solution to be tested;

[0046] The second detection unit is used to perform Raman spectroscopy detection on the mixture and calculate the concentration of mercury ions in the sample solution based on the peak area of ​​the known characteristic peaks.

[0047] Optionally, the first mixing unit includes:

[0048] The nano-gold Raman enhancer and mercury ion reference solution were mixed at a volume ratio of 0.1-10:1, and then an agglomerating agent was added. The mixture was allowed to stand for a preset time. The agglomerating agent contained metal salt ions.

[0049] The second mixing unit includes:

[0050] The nano-gold Raman enhancer and the sample solution to be tested are mixed at a volume ratio of 0.1-10:1, and then an agglomerating agent is added. The mixture is then allowed to stand for a preset time. The agglomerating agent contains metal salt ions.

[0051] The fourth aspect of this application provides an apparatus for preparing a nano-gold Raman enhancer, comprising:

[0052] The acquisition unit is used to acquire a chloroauric acid solution of a preset concentration and heat the chloroauric acid solution to boiling.

[0053] The third mixing unit is used to add sodium citrate solution as a reducing agent to the chloroauric acid solution and to stir it.

[0054] A cooling unit is used to cool the stirred solution to generate nano-gold sol;

[0055] The fourth mixing unit is used to add a thiuram solution of a preset concentration to the gold nanoparticle sol and mix it evenly.

[0056] The incubation unit is used to incubate the mixed solution at room temperature for a preset time period.

[0057] The concentration unit is used to centrifuge and concentrate the mixed solution after incubation.

[0058] The resolution unit is used to add a resolution solution to the mixed solution after centrifugation and concentration to generate nano-gold Raman enhancers.

[0059] Optionally, the acquisition unit includes:

[0060] Obtain an Aml chloroauric acid solution with a mass fraction of 0.01%, and heat the chloroauric acid solution to boiling.

[0061] The third mixing unit includes:

[0062] Add B ml of 1% sodium citrate solution as a reducing agent to the chloroauric acid solution and stir. The ratio of A to B is 100:1.

[0063] Optional, concentration units include:

[0064] The incubated mixed solution was centrifuged and concentrated to produce X ml of concentrated solution;

[0065] The resolution unit includes:

[0066] Add Y ml of reconstituted solution to the mixed solution after centrifugation and concentration to reconstitute and generate nano-gold Raman enhancer, where X:Y is 1-20:10-200.

[0067] Optionally, the reconstitution solution can be ultrapure water, sodium citrate solution, CTAB solution, CTAC solution, ethylene glycol solution, PvP solution, PEG solution, or PBS solution.

[0068] Optionally, a fourth mixing unit includes:

[0069] Add 0.01mM-1mM thiuram solution to the gold nanoparticle sol and mix thoroughly.

[0070] Optional incubation units include:

[0071] The mixed solution was incubated at a temperature of 0-60 degrees Celsius for 72 hours.

[0072] The fifth aspect of this application provides an electronic device, comprising:

[0073] Processor, memory, input / output units, and bus;

[0074] The processor is connected to memory, input / output units, and a bus;

[0075] The memory stores a program, which the processor calls to execute, such as the first aspect and any optional Raman detection method of the first aspect.

[0076] The sixth aspect of this application provides a computer-readable storage medium on which a program is stored, which, when executed on a computer, performs the first aspect and any optional Raman detection method of the first aspect.

[0077] The seventh aspect of this application provides an electronic device, comprising:

[0078] Processor, memory, input / output units, and bus;

[0079] The processor is connected to memory, input / output units, and a bus;

[0080] The memory stores a program, which the processor calls to execute, as in the second aspect and any optional preparation method of the second aspect.

[0081] The eighth aspect of this application provides a computer-readable storage medium on which a program is stored, which, when executed on a computer, performs the preparation method as described in the second aspect and any optional preparation method of the second aspect.

[0082] As can be seen from the above technical solutions, the embodiments of this application have the following advantages:

[0083] In this application, a gold nanoparticle Raman enhancer is first prepared using chloroauric acid solution, sodium citrate solution, and thiuram solution. The gold nanoparticle sol contains one or more of the following: spherical gold nanoparticles, ellipsoidal gold nanoparticles, polygonal gold nanoparticles, rod-shaped gold nanoparticles, and star-shaped gold nanoparticles. The gold nanoparticle Raman enhancer is added to a mercury ion reference solution, and the mixture is subjected to Raman spectroscopy to generate a spectrum. The target characteristic peak is determined from the spectrum as the discrimination criterion for enhanced Raman scattering spectroscopy detection of mercury ions, and a positive correlation is established between the mercury ion concentration and the intensity of the characteristic peak. The mercury ion reference solution is a solution with a known mercury ion concentration. The gold nanoparticle Raman enhancer is then added to the sample solution to be tested, and the mixture is subjected to Raman spectroscopy. The mercury ion concentration in the sample solution is calculated based on the peak area of ​​the known characteristic peak. This application utilizes nanosurface modification and surface molecular complexation techniques to develop a nano-gold Raman enhancer using chloroauric acid solution, sodium citrate solution, and thiuram solution. This nano-gold Raman enhancer is a stable and specific Raman enhancement material. The thiuram molecules on the surface of the gold nanoparticles in the nano-gold Raman enhancer utilize thiuram molecules to capture mercury ions, causing intramolecular breakage and regenerating Hg-S complex structures. This alters the molecular structure of the labeled molecules on the particle surface, resulting in a Raman signal that is clearly distinguishable from the original labeled molecules under an excitation light source. Based on the generation of characteristic peaks at Raman shifts of 474 cm⁻¹, 528 cm⁻¹, and 681 cm⁻¹, and the shift at 1388 cm⁻¹, the detection of heavy metal mercury ions can be achieved. This reduces the likelihood of false positives due to the single characteristic peak, lowers the error, and improves the accuracy of heavy metal mercury ion detection. Attached Figure Description

[0084] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0085] Figure 1 This is a schematic diagram of an embodiment of the mercury ion detection method in this application;

[0086] Figure 2 This is a schematic diagram of the Raman signals after adding different concentrations of mercury ions to the reference solution in this application.

[0087] Figure 3 This is a schematic diagram of another embodiment of the mercury ion detection method in this application;

[0088] Figure 4 This is a schematic diagram of an embodiment of the preparation method of the nano-gold Raman enhancer in this application;

[0089] Figure 5 This is a schematic diagram of one embodiment of the mercury ion detection device in this application;

[0090] Figure 6 This is a schematic diagram of an embodiment of the apparatus for preparing the nano-gold Raman enhancer in this application;

[0091] Figure 7 This is a schematic diagram of one embodiment of the electronic device of this application;

[0092] Figure 8 This is a schematic diagram of one embodiment of the electronic device of this application;

[0093] Figure 9 This is a schematic diagram illustrating the reaction between mercury ions and thiuram molecules in this application;

[0094] Figure 10 This is a schematic diagram of the reaction between thiolam molecules and gold nanoparticles in this application. Detailed Implementation

[0095] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods have been omitted so as not to obscure the description of this application with unnecessary detail.

[0096] It should be understood that, when used in this application specification and the appended claims, the term "comprising" indicates the presence of the described features, integrals, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or a collection thereof.

[0097] It should also be understood that the term “and / or” as used in this application specification and the appended claims means any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0098] As used in this application specification and the appended claims, the term "if" may be interpreted, depending on the context, as "when," "once," "in response to determination," or "in response to detection." Similarly, the phrase "if determined" or "if detected [the described condition or event]" may be interpreted, depending on the context, as meaning "once determined," "in response to determination," "once detected [the described condition or event]," or "in response to detection [the described condition or event]."

[0099] Furthermore, in the description of this application and the appended claims, the terms "first," "second," "third," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0100] References to "one embodiment" or "some embodiments" as described in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0101] In summary, existing methods for detecting mercury ions are prone to producing erroneous results, reducing the accuracy of mercury ion detection.

[0102] Based on this, this application discloses a method and apparatus for detecting mercury ions, and a method for preparing a nano-gold Raman enhancer, which can be used to improve the detection accuracy of heavy metal mercury ions.

[0103] The technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0104] The method described in this application can be applied to servers, devices, terminals, or other devices with logical processing capabilities; therefore, this application does not limit its application. For ease of description, the following description uses a terminal as the executing entity.

[0105] Please see Figure 1 This application provides an embodiment of a method for detecting mercury ions, comprising:

[0106] 101. A nano-gold Raman enhancer is prepared using chloroauric acid solution, sodium citrate solution and thiuram solution, wherein the nano-gold sol contains one or more of spherical gold nanoparticles, ellipsoidal gold nanoparticles, polygonal gold nanoparticles, rod-shaped gold nanoparticles and star-shaped gold nanoparticles.

[0107] 102. Add the nano-gold Raman enhancer to the mercury ion reference solution;

[0108] 103. Perform Raman spectroscopy on the mixture to generate a spectrum;

[0109] 104. Characteristic peaks are determined from the spectrum as the basis for discrimination of mercury ion detection by enhanced Raman scattering spectroscopy, and it is determined that the concentration of mercury ions is positively correlated with the intensity of characteristic peaks. The mercury ion reference solution is a solution with a known concentration of mercury ions.

[0110] 105. Add the nano-gold Raman enhancer to the sample solution to be tested;

[0111] 106. Perform Raman spectroscopy on the mixture and calculate the mercury ion concentration in the sample solution based on the known peak areas of the characteristic peaks.

[0112] In this embodiment, the gold nanoparticle Raman enhancer is prepared using chloroauric acid solution, sodium citrate solution, and thiuram solution. The specific preparation method will be described in detail later. In this embodiment, the prepared gold nanoparticle Raman enhancer contains gold nanoparticle sol, which contains one or more of the following: spherical gold nanoparticles, ellipsoidal gold nanoparticles, polygonal gold nanoparticles, rod-shaped gold nanoparticles, and star-shaped gold nanoparticles.

[0113] First, the gold nanoparticle Raman enhancer is added to a reference solution of mercury ions with a known concentration. Then, Raman spectroscopy is performed on the mixture to generate a spectrum. Characteristic peaks (target characteristic peaks) at 474 cm⁻¹, 528 cm⁻¹, and 681 cm⁻¹ are identified from the spectrum as the criteria for detecting mercury ions using enhanced Raman scattering spectroscopy. It is determined that the mercury ion concentration is positively correlated with the intensity of the characteristic peaks, thus obtaining reference data for detecting mercury ion concentration. The gold nanoparticle Raman enhancer can then be added to the sample solution to be tested, and Raman spectroscopy is performed on the mixture. The mercury ion concentration in the sample solution can be calculated based on the peak areas of the known characteristic peaks.

[0114] In this embodiment, a nano-gold Raman enhancer was developed using nano-surface modification and surface molecular complexation techniques via chloroauric acid solution, sodium citrate solution, and thiuram solution. This nano-gold Raman enhancer is a stable and specific Raman enhancing material. The thiuram molecules on the surface of the gold nanoparticles in the nano-gold Raman enhancer capture mercury ions using thiol groups, forming an S-Hg-S chelate structure. This alters the molecular structure of the labeled molecules on the particle surface, resulting in a Raman signal that is clearly distinguishable from the original labeled molecules under an excitation light source. Based on the generation of characteristic peaks at Raman shifts of 474 cm⁻¹, 528 cm⁻¹, and 681 cm⁻¹, and the shift at 1388 cm⁻¹, the detection of heavy metal mercury ions can be achieved. This reduces the likelihood of false positives due to the single characteristic peak, lowers the error, and improves the accuracy of heavy metal mercury ion detection.

[0115] Please refer toFigure 2 Through a series of experiments, this invention has been verified to obtain excellent detection limits and stable detection results, and has high practical application value in fields such as environmental monitoring and aquaculture.

[0116] Figure 2 The horizontal axis represents the Raman shift, and the vertical axis represents the intensity. This can be compared with the blank signal; the addition of mercury ions produces new peak positions, which are used to identify mercury ions. The blank signal is essentially the thiuram signal. The four curves in the figure correspond to the Raman detection curves obtained from thiuram solutions, and the curves obtained after adding nano-gold Raman enhancers to solutions with mercury ion concentrations of 200 ppb, 100 ppb, and 500 ppb. It can be seen that three characteristic peaks exist at 474 cm⁻¹, 528 cm⁻¹, and 681 cm⁻¹.

[0117] Please refer to Figure 9 , Figure 9 This is a schematic diagram of the reaction between mercury ions and thiuram molecules.

[0118] Please refer to Figure 10 , Figure 10 This is a schematic diagram of the reaction between thiuram molecules and gold nanoparticles.

[0119] Please see Figure 3 This application provides an embodiment of a method for preparing a nano-gold Raman enhancer, comprising:

[0120] 301. A nano-gold Raman enhancer is prepared by using chloroauric acid solution, sodium citrate solution and thiuram solution, wherein the nano-gold sol contains one or more of spherical gold nanoparticles, ellipsoidal gold nanoparticles, polygonal gold nanoparticles, rod-shaped gold nanoparticles and star-shaped gold nanoparticles.

[0121] 302. Mix the nano-gold Raman enhancer and mercury ion reference solution at a volume ratio of 0.1-10:1, then add the agglomerating agent, mix and let stand for a preset time. The agglomerating agent contains metal salt ions.

[0122] 303. Perform Raman spectroscopy on the mixture to generate a spectrum;

[0123] 304. The target characteristic peaks are determined from the spectrum as the basis for the discrimination of mercury ion detection by enhanced Raman scattering spectroscopy, and it is determined that the concentration of mercury ions is positively correlated with the intensity of the characteristic peaks. The mercury ion reference solution is a solution with a known concentration of mercury ions.

[0124] 305. Mix the nano-gold Raman enhancer and the sample solution to be tested at a volume ratio of 0.1-10:1, then add the agglomerating agent, mix and let stand for a preset time. The agglomerating agent contains metal salt ions.

[0125] 306. Perform Raman spectroscopy on the mixture and calculate the mercury ion concentration in the sample solution based on the known peak areas of the characteristic peaks.

[0126] In this embodiment, the nano-gold Raman enhancer and the test sample solution need to be mixed in a certain ratio to enhance the reaction effect. 0.1-10 volumes of nano-gold Raman enhancer are added to 1 volume of the test sample solution, and an agglomerating agent is added to promote particle coupling, resulting in a better signal effect. The agglomerating agent in this embodiment is generally a compound or mixture containing metal salt ions.

[0127] Please see Figure 4 This application provides an embodiment of a method for preparing a nano-gold Raman enhancer, comprising:

[0128] 401. Obtain a chloroauric acid solution of a preset concentration and heat the chloroauric acid solution to boiling.

[0129] 402. Add sodium citrate solution as a reducing agent to the chloroauric acid solution and stir.

[0130] 403. Cool the stirred solution to generate nano-gold sol;

[0131] 404. Add a thiuram solution of the preset concentration to the gold nanoparticle sol and mix well;

[0132] 405. Incubate the mixed solution at room temperature for a preset time period;

[0133] 406. The incubated mixture is then concentrated by centrifugation;

[0134] 407. Add a reconstituted solution to the mixed solution after centrifugation and concentration to reconstitute and generate nano-gold Raman enhancer.

[0135] In this embodiment, A ml of 0.01% chloroauric acid solution was obtained and heated to boiling. Then, B ml of 1% sodium citrate solution was added as a reducing agent to the chloroauric acid solution, and the mixture was stirred magnetically for 30 minutes, with A:B ratio of 100:1. The stirred solution was then cooled to generate a gold nanoparticle sol. A 0.01 mM-1 mM thiuram solution was added to the gold nanoparticle sol and mixed thoroughly. The mixture was then incubated at 0-60 degrees Celsius for 72 hours. The incubated mixture was centrifuged and concentrated to generate X ml of concentrated solution. Y ml of reconstitution solution was added to the centrifuged and concentrated mixture for reconstitution to generate a gold nanoparticle Raman enhancer, with X:Y ratio of 1-20:10-200.

[0136] The reconstitution solution can be ultrapure water, sodium citrate solution, CTAB solution, CTAC solution, ethylene glycol solution, PvP solution, PEG solution, or PBS solution.

[0137] This embodiment utilizes surface-enhanced Raman spectroscopy, employing nanosurface modification and surface molecular complexation techniques, to develop a method for detecting mercury ions with specific, multiple identifiable characteristic peaks. In an environment with a 10x signal-to-noise ratio, the detection limit reaches 20 ppb, representing a breakthrough achievement in this field. This provides crucial technical support for the application of surface-enhanced Raman spectroscopy in environmental monitoring, aquaculture, and food safety.

[0138] The following are examples illustrating specific embodiments:

[0139] This embodiment describes the preparation process of the nano-gold Raman enhancer: 100 mL of 0.01% HAuCl4 solution (chloroauric acid solution) was heated to boiling, and 1 mL of 1% sodium citrate solution was added as a reducing agent. The mixture was magnetically stirred for 30 min, and after cooling, a gold sol was obtained. 1 mL of 0.1 mM thiuram solution was added to the gold sol, mixed well, and incubated at room temperature for 2 h. The mixture was then concentrated to 10 mL by centrifugation, and 90 mL of ultrapure water was added to redissolve the concentrate, thus generating the nano-gold Raman enhancer.

[0140] This example demonstrates the detection of mercury ions, a heavy metal, in aquaculture water. The specific operating steps are as follows:

[0141] Preparation of standards: Prepare mercury ion standards of 0 ppm, 5 ppm, 10 ppm, and 20 ppm respectively in 0.1 M HNO3 solution;

[0142] Simulated sample preparation: Add 100 μL of the above standard to 10 mL of aquaculture water, and then add 100 μL of 1M HNO3 solution, labeled as blank, 50 ppb, 100 ppb, and 200 ppb.

[0143] Pretreatment: Centrifuge the above-mentioned aquaculture water at 10,000 rpm for 3 minutes, and the supernatant is the test solution.

[0144] Raman detection: Take 100 μL of the above supernatant, add 100 μL of Au@TRM, mix well, and then use a 785 nm laser with a laser power of 250 mw and an integration time of 5 s for detection.

[0145] Please see Figure 5 This application provides an embodiment of a Raman detection device for mercury ions, comprising:

[0146] Preparation unit 501 is used to prepare nano-gold Raman enhancers with chloroauric acid solution, sodium citrate solution and thiuram solution, wherein the nano-gold sol contains one or more of spherical gold nanoparticles, ellipsoidal gold nanoparticles, polygonal gold nanoparticles, rod-shaped gold nanoparticles and star-shaped gold nanoparticles.

[0147] The first mixing unit 502 is used to add the nano-gold Raman enhancer to the mercury ion reference solution;

[0148] Optionally, the first mixing unit 502 includes:

[0149] The nano-gold Raman enhancer and mercury ion reference solution were mixed at a volume ratio of 0.1-10:1, and then an agglomerating agent was added. The mixture was then allowed to stand for a preset time. The agglomerating agent contained metal salt ions.

[0150] The first detection unit 503 is used to perform Raman spectroscopy detection on the mixture and generate a spectrum.

[0151] The determination unit 504 is used to determine the target characteristic peak from the spectrum as the discrimination basis for the detection of mercury ions by enhanced Raman scattering spectroscopy, and to determine that the concentration of mercury ions is positively correlated with the intensity of the characteristic peak. The mercury ion reference solution is a solution with a known concentration of mercury ions.

[0152] The second mixing unit 505 is used to add the nano-gold Raman enhancer to the sample solution to be tested;

[0153] The second mixing unit 505 includes:

[0154] The nano-gold Raman enhancer and the sample solution to be tested are mixed at a volume ratio of 0.1-10:1, and then an agglomerating agent is added. The mixture is then allowed to stand for a preset time. The agglomerating agent contains metal salt ions.

[0155] The second detection unit 506 is used to perform Raman spectroscopy detection on the mixture and calculate the concentration of mercury ions in the sample solution based on the peak area of ​​the known characteristic peaks.

[0156] Please see Figure 6 This application provides an embodiment of an apparatus for preparing a nano-gold Raman enhancer, comprising:

[0157] The acquisition unit 601 is used to acquire a chloroauric acid solution of a preset concentration and heat the chloroauric acid solution to boiling.

[0158] Optionally, the acquisition unit 601 includes:

[0159] Obtain an Aml chloroauric acid solution with a mass fraction of 0.01%, and heat the chloroauric acid solution to boiling.

[0160] The third mixing unit 602 is used to add sodium citrate solution as a reducing agent to chloroauric acid solution and to stir it.

[0161] The third mixing unit 602 includes:

[0162] Add B ml of 1% sodium citrate solution as a reducing agent to the chloroauric acid solution and stir. The ratio of A to B is 100:1.

[0163] Cooling unit 603 is used to cool the stirred solution to generate nano-gold sol;

[0164] The fourth mixing unit 604 is used to add a thiuram solution of a preset concentration to the gold nanoparticle sol and mix them evenly.

[0165] Optionally, the fourth mixing unit 604 includes:

[0166] Add 0.01mM-1mM thiuram solution to the gold nanoparticle sol and mix thoroughly.

[0167] The incubation unit 605 is used to incubate the mixed solution at room temperature for a preset time period.

[0168] Optionally, incubation unit 605 includes:

[0169] The mixed solution was incubated at a temperature of 00°C-60°C for 72 hours.

[0170] Concentration unit 606 is used to centrifuge and concentrate the mixed solution after incubation.

[0171] Optionally, the concentration unit 606 includes:

[0172] The incubated mixed solution was centrifuged and concentrated to produce X ml of concentrated solution.

[0173] The resolution unit 607 is used to add a resolution solution to the mixed solution after centrifugation and concentration to generate nano-gold Raman enhancer.

[0174] Resolution unit 607 includes:

[0175] Add Y ml of reconstituted solution to the mixed solution after centrifugation and concentration to reconstitute and generate nano-gold Raman enhancer, where X:Y is 1-20:10-200.

[0176] Optionally, the reconstitution solution can be ultrapure water, sodium citrate solution, CTAB solution, CTAC solution, ethylene glycol solution, PvP solution, PEG solution, or PBS solution.

[0177] Please see Figure 7 This application provides an electronic device, including:

[0178] Processor 701, memory 703, input / output unit 702, and bus 704.

[0179] The processor 701 is connected to the memory 703, the input / output unit 702, and the bus 704.

[0180] The memory 703 stores a program, and the processor 701 calls the program to execute it, such as... Figure 1 , Figure 3 Methods for detecting mercury ions in [the environment].

[0181] This application provides a computer-readable storage medium on which a program is stored, and when the program is executed on a computer, it performs the following... Figure 1 , Figure 3 Methods for detecting mercury ions in [the environment].

[0182] Please see Figure 8 This application provides an electronic device, including:

[0183] Processor 801, memory 803, input / output unit 802, and bus 804.

[0184] The processor 801 is connected to the memory 803, the input / output unit 502, and the bus 804.

[0185] The memory 803 stores a program, and the processor 801 calls the program to execute it, such as... Figure 4 Preparation method of nano-gold Raman enhancer in [the context of the invention].

[0186] This application provides a computer-readable storage medium on which a program is stored, and when the program is executed on a computer, it performs the following... Figure 4 Preparation method of nano-gold Raman enhancer in [the context of the invention].

[0187] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0188] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection between apparatuses or units through some interfaces, and may be electrical, mechanical, or other forms.

[0189] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0190] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0191] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

Claims

1. A Raman detection method for mercury ions, characterized in that, include: Obtain a chloroauric acid solution of a preset concentration and heat the chloroauric acid solution to boiling. Sodium citrate solution was added to the chloroauric acid solution as a reducing agent, and the mixture was stirred. The stirred solution was cooled to generate nano-gold sol; Add a thiuram solution of a predetermined concentration to the gold nanoparticle sol and mix thoroughly. The mixed solution was incubated at room temperature for a preset time period; The incubated mixed solution is then concentrated by centrifugation. A reconstitution solution was added to the mixed solution after centrifugation and concentration to reconstitute it and generate nano-gold Raman enhancer. A nano-gold Raman enhancer was prepared using chloroauric acid solution, sodium citrate solution and thiuram solution, wherein the nano-gold sol in the nano-gold enhancer contains one or more of spherical gold nanoparticles, ellipsoidal gold nanoparticles, polygonal gold nanoparticles, rod-shaped gold nanoparticles and star-shaped gold nanoparticles. The nano-gold Raman enhancer was added to a mercury ion reference solution; The mixture was subjected to Raman spectroscopy to generate a spectrum; The target characteristic peak is determined from the spectrum as the discrimination criterion for enhanced Raman scattering spectroscopy to detect mercury ions, and it is determined that the concentration of mercury ions is positively correlated with the intensity of the characteristic peak. The mercury ion reference solution is a solution with a known concentration of mercury ions. Add the nano-gold Raman enhancer to the sample solution; The mixture was subjected to Raman spectroscopy, and the concentration of mercury ions in the sample solution was calculated based on the peak areas of the known characteristic peaks.

2. The Raman detection method according to claim 1, characterized in that, Adding the aforementioned nano-gold Raman enhancer to a mercury ion reference solution includes: The nano-gold Raman enhancer and mercury ion reference solution are mixed at a volume ratio of 0.1-10:1, and then an agglomerating agent is added. The mixture is then allowed to stand for a preset time. The agglomerating agent contains metal salt ions. Adding the nano-gold Raman enhancer to the sample solution includes: The nano-gold Raman enhancer and the sample solution to be tested are mixed at a volume ratio of 0.1-10:1, and then an agglomerating agent is added. The mixture is then allowed to stand for a preset time. The agglomerating agent contains metal salt ions.

3. The Raman detection method according to claim 2, characterized in that, The step of obtaining a chloroauric acid solution of a preset concentration by heating the chloroauric acid solution to boiling includes: Obtain an Aml chloroauric acid solution with a mass fraction of 0.01%, and heat the chloroauric acid solution to boiling. The step of adding sodium citrate solution as a reducing agent to the chloroauric acid solution and stirring includes: Add B ml of 1% sodium citrate solution as a reducing agent to the chloroauric acid solution and stir. The ratio of A to B is 100:

1.

4. The Raman detection method according to claim 2, characterized in that, The incubated mixture is then concentrated by centrifugation, including: The incubated mixed solution was centrifuged and concentrated to produce X ml of concentrated solution; A reconstitution solution was added to the centrifuged and concentrated mixed solution for reconstitution treatment to generate a nano-gold Raman enhancer, including: Add Y ml of reconstituted solution to the mixed solution after centrifugation and concentration to reconstitute and generate nano-gold Raman enhancer, where X:Y is 1-20:10-200.

5. The Raman detection method according to claim 4, characterized in that, The reconstitution solution is ultrapure water, sodium citrate solution, CTAB solution, CTAC solution, ethylene glycol solution, PvP solution, PEG solution, or PBS solution.

6. The Raman detection method according to any one of claims 1, 4 to 5, characterized in that, A thiuram solution of a predetermined concentration is added to the gold nanoparticle sol and mixed thoroughly, comprising: Add a 0.01mM-1mM thiuram solution to the gold nanoparticle sol and mix thoroughly.

7. The Raman detection method according to any one of claims 1, 4 to 5, characterized in that, The incubation of the mixed solution at room temperature for a preset time period includes: The mixed solution was incubated at a temperature of 0°C to 60°C for 72 hours.

8. A Raman detection device for mercury ions, characterized in that, include: The acquisition unit is used to acquire a chloroauric acid solution of a preset concentration and heat the chloroauric acid solution to boiling. The third mixing unit is used to add sodium citrate solution as a reducing agent to the chloroauric acid solution and to stir it. A cooling unit is used to cool the stirred solution to generate nano-gold sol; The fourth mixing unit is used to add a thiuram solution of a preset concentration to the gold nanoparticle sol and mix them evenly. The incubation unit is used to incubate the mixed solution at room temperature for a preset time period. The concentration unit is used to centrifuge and concentrate the mixed solution after incubation. The resolution unit is used to add a resolution solution to the mixed solution after centrifugation and concentration to generate nano-gold Raman enhancer; The preparation unit is used to prepare a gold nanoparticle Raman enhancer using chloroauric acid solution, sodium citrate solution and thiuram solution, wherein the gold nanoparticle Raman enhancer contains one or more of the following: spherical gold nanoparticles, ellipsoidal gold nanoparticles, polygonal gold nanoparticles, rod-shaped gold nanoparticles and star-shaped gold nanoparticles. The first mixing unit is used to add the nano-gold Raman enhancer to the mercury ion reference solution; The first detection unit is used to perform Raman spectroscopy detection on the mixture and generate a spectrum. The determination unit is used to determine the target characteristic peak from the spectrum as the discrimination basis for the detection of mercury ions by enhanced Raman scattering spectroscopy, and to determine that the concentration of mercury ions is positively correlated with the intensity of the characteristic peak. The mercury ion reference solution is a solution with a known concentration of mercury ions. The second mixing unit is used to add the nano-gold Raman enhancer to the sample solution to be tested; The second detection unit is used to perform Raman spectroscopy detection on the mixture and calculate the concentration of mercury ions in the sample solution based on the peak area of ​​the known characteristic peaks.

Images