Mercury ion detection method

Abstract

The embodiment of the present application discloses a method for detecting mercury ions, which comprises adding gold nanoparticles to a liquid to be detected, and then obtaining a first detection result based on the plasma response of the gold nanoparticles and mercury ions; obtaining a second detection result based on the nanozyme response of the gold nanoparticles and mercury ions; and finally outputting a detection conclusion that the liquid to be detected contains mercury ions only when the first detection result and the second detection result both show the presence of mercury ions. Based on this, the mercury ion detection method provided by the embodiment of the present application uses gold nanoparticles to detect mercury ions through a dual-channel confirmation method. On the one hand, it has the characteristics of simple operation, economical cost, easy-to-read signals and fast detection. On the other hand, the detection result is determined to contain mercury ions only when the first detection result and the second detection result both satisfy the detection result that mercury ions are present. Based on this, the influence of interferences on the detection result can be reduced, false positive signal response can be avoided, and the detection accuracy can be improved.

Description

Technical Field

[0001] The embodiments of the present application relate to the technical field of mercury ion detection, and in particular to a mercury ion detection method. Background Art

[0002] With the continuous development of modern industry, environmental pollution caused by heavy metal ions has always attracted much attention. As one of the most common heavy metal ion pollutants in industrial applications, mercury ions (Hg 2+ ) poses a great threat to human health. 2+ It can be widely distributed in soil, air and water. Once humans come into contact with it, even a small amount of Hg 2+ It can also cause a series of clinical symptoms such as nausea, vomiting, fever, etc., leading to irreversible damage to various organs. Therefore, it is necessary to develop an instant, fast and convenient environmental Hg 2+ Detection and monitoring methods are very important for the ecological environment and human health.

[0003] To overcome these challenges of environmental pollution and health risks, researchers have developed a series of Hg 2+ Sensing methods are being developed to improve the ecological environment and public health, such as atomic absorption spectrometry (AAS), inductively coupled plasma atomic emission spectrometry (ICP-AES), inductively coupled plasma mass spectrometry (ICP-MS), and electrochemical methods. Although these detection methods based on traditional instruments can complete the detection of Hg 2+ However, they usually involve expensive instruments, long detection time and complicated operation procedures, and thus cannot meet the sensing requirements for on-site detection and rapid analysis. Therefore, it is necessary to develop simple and convenient Hg 2+ Point-of-care testing (POCT) methods are used to detect Hg in various contaminated sites. 2+ Rapid testing. Summary of the invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art or related art.

[0005] The present application embodiment proposes a method for detecting mercury ions, comprising:

[0006] adding gold nanoparticles to the liquid to be tested;

[0007] Obtaining a first detection result based on the plasma response of the gold nanoparticles and the mercury ions;

[0008] Obtaining a second detection result based on the nanozyme response of the gold nanoparticles and the mercury ions;

[0009] Only when both the first detection result and the second detection result show the presence of mercury ions, a detection conclusion that the liquid to be detected contains mercury ions is output.

[0010] In a feasible implementation, when any one of the first detection result and the second detection result shows that mercury ions do not exist in the liquid to be detected, a detection conclusion that the liquid to be detected does not contain mercury ions is output.

[0011] In a feasible implementation manner, the step of obtaining a first detection result based on the plasma response of gold nanoparticles and mercury ions includes:

[0012] Add AuNPs solution to the liquid to be tested and incubate for 30 min;

[0013] Add working buffer solution to the solution;

[0014] The color and Vis-NIR spectrum changes of the liquid solution are recorded by image acquisition equipment and UV-visible spectrophotometer;

[0015] Based on the changes in liquid color and Vis-NIR spectrum, a first detection result is obtained.

[0016] In a feasible embodiment, the pH value of the working buffer solution is 7.4;

[0017] The working buffer solution is a 0.02 M Tris-HCl buffer solution containing 0.1 M NaCl and 5 mM KCl.

[0018] In a feasible implementation manner, the step of obtaining a first detection result based on the liquid color and Vis-NIR spectrum changes includes:

[0019] When the absorbance ratio at 650 nm to 530 nm in the Vis-NIR spectrum is greater than or equal to 0.4, the output contains mercury ions;

[0020] When the absorbance ratio at 650 nm to 530 nm in the Vis-NIR spectrum is less than 0.4, the output does not contain mercury ions.

[0021] In a feasible embodiment, the step of obtaining a second detection result based on the nanozyme response of the gold nanoparticles and mercury ions includes:

[0022] After the plasma response was completed, H2O2 and TMB solutions were added to the solution;

[0023] Again, the color and Vis-NIR spectrum changes of the liquid solution are recorded by an image acquisition device and a UV-visible spectrophotometer;

[0024] Based on the changes in liquid color and Vis-NIR spectrum, a second detection result is obtained.

[0025] In a feasible implementation manner, the step of obtaining the second detection result based on the liquid color and Vis-NIR spectrum changes includes:

[0026] When the value at 652 nm in the Vis-NIR spectrum is greater than or equal to 0.5, the output contains mercury ions;

[0027] When the value at 652 nm in the Vis-NIR spectrum is less than 0.5, the output contains mercury ions.

[0028] In a feasible embodiment, the mercury ion detection method further includes:

[0029] AuNPs solution was prepared by reducing HAuCl4 with citric acid.

[0030] Compared with the prior art, the present invention has at least the following beneficial effects:

[0031] The mercury ion detection method provided in the embodiment of the present application adds gold nanoparticles to the liquid to be detected, and then obtains a first detection result based on the plasma response of the gold nanoparticles and mercury ions; obtains a second detection result based on the nanozyme response of the gold nanoparticles and mercury ions; finally, only when the first detection result and the second detection result both show the presence of mercury ions, outputs the detection conclusion that the liquid to be detected contains mercury ions. Based on this, the mercury ion detection method provided in the embodiment of the present application uses gold nanoparticles to detect mercury ions through a dual-channel confirmation method. On the one hand, it has the characteristics of simple operation, cost-effectiveness, easy-to-read signals and fast detection; on the other hand, only when the first detection result and the second detection result both satisfy the detection result that mercury ions are present, the detection result is determined to contain mercury ions. Based on this, the influence of interferences on the detection result can be reduced, false positive signal response can be avoided, and the detection accuracy can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0033] Figure 1 A schematic flowchart of the steps of a mercury ion detection method according to an embodiment of the present application;

[0034] Figure 2Vis-NIR absorption spectra of different components and corresponding solution colors in a mercury ion detection method provided in an embodiment of the present application;

[0035] Figure 3 a and Figure 3 b is a TEM image of different components in a mercury ion detection method according to an embodiment of the present application;

[0036] Figure 4 Vis-NIR absorption spectra of different components and corresponding solution colors in a mercury ion detection method provided in an embodiment of the present application;

[0037] Figure 5 In the mercury ion detection method provided in an embodiment of the present application, the sensing system is in Hg 2+ Hg 4f XPS spectra on the surface of AuNPs in the presence of;

[0038] Figure 6 a is the color of different interfering substance solutions related to AuNPs plasma response in a mercury ion detection method provided in an embodiment of the present application;

[0039] Figure 6 b is the color of different interfering substance solutions related to the response of AuNPs nanozyme in a mercury ion detection method according to an embodiment of the present application;

[0040] Figure 6 c is Figure 6 a The corresponding Vis-NIR absorption spectrum;

[0041] Figure 6 d is Figure 6 b Corresponding Vis-NIR absorption spectrum;

[0042] Figure 7 a is a different interferent A related to AuNPs plasma response in a mercury ion detection method provided in an embodiment of the present application 650 / A 530 Value diagram;

[0043] Figure 7 b is a different interferent A related to the response of AuNPs nanozyme in a mercury ion detection method according to an embodiment of the present application 652 value;

[0044] Figure 8 A schematic diagram of an AND logic gate of a mercury ion detection method provided in an embodiment of the present application;

[0045] Fig. 9 This is a schematic diagram of the truth value representation of AuNPs dual-response logic gate to different interferents in a mercury ion detection method provided in an embodiment of the present application;

[0046] Fig.10 a is a mercury ion detection method provided in an embodiment of the present application in which different Hg 2+ Color plots of concentration-responsive solutions;

[0047] Fig.10 b is a mercury ion detection method according to an embodiment of the present application. Fig.10 a The corresponding Vis-NIR absorption spectrum;

[0048] Fig.10 c is a mercury ion detection method according to an embodiment of the present application. Fig.10 b The corresponding AuNPs single-response colorimetric sensing system A 650 / A 530 With Hg 2+ Linear relationship graph between concentrations;

[0049] Fig.11 a is a mercury ion detection method provided in an embodiment of the present application in the AuNPs dual-response colorimetric sensor system of different Hg 2+ Color plots of concentration-responsive solutions;

[0050] Fig.11 b is a mercury ion detection method according to an embodiment of the present application. Fig.11 a The corresponding Vis-NIR absorption spectrum;

[0051] Fig.11 c is a mercury ion detection method according to an embodiment of the present application. Fig.11 b The corresponding AuNPs single-response colorimetric sensing system A 650 / A 530 With Hg 2+ Linear relationship between concentrations. DETAILED DESCRIPTION

[0052] In order to better understand the above-mentioned technical scheme, the technical scheme of the embodiments of the present application is described in detail below through the accompanying drawings and specific embodiments. It should be understood that the embodiments of the present application and the specific features in the embodiments are detailed descriptions of the technical scheme of the embodiments of the present application, rather than limitations on the technical scheme of the present application. In the absence of conflict, the embodiments of the present application and the technical features in the embodiments may be combined with each other.

[0053] like Figure 1 As shown, the embodiment of the present application proposes a method for detecting mercury ions, comprising:

[0054] Step 101: adding gold nanoparticles to the liquid to be detected;

[0055] Step 102: obtaining a first detection result based on the plasma response of the gold nanoparticles and the mercury ions;

[0056] Step 103: obtaining a second detection result based on the nanozyme response of the gold nanoparticles and mercury ions;

[0057] Step 104: Only when both the first detection result and the second detection result show the presence of mercury ions, output a detection conclusion that the liquid to be detected contains mercury ions.

[0058] The mercury ion detection method provided in the embodiment of the present application adds gold nanoparticles to the liquid to be detected, and then obtains a first detection result based on the plasma response of the gold nanoparticles and mercury ions; obtains a second detection result based on the nanozyme response of the gold nanoparticles and mercury ions; finally, only when the first detection result and the second detection result both show the presence of mercury ions, outputs the detection conclusion that the liquid to be detected contains mercury ions. Based on this, the mercury ion detection method provided in the embodiment of the present application uses gold nanoparticles to detect mercury ions through a dual-channel confirmation method. On the one hand, it has the characteristics of simple operation, cost-effectiveness, easy-to-read signals and fast detection; on the other hand, only when the first detection result and the second detection result both satisfy the detection result that mercury ions are present, the detection result is determined to contain mercury ions. Based on this, the influence of interferences on the detection result can be reduced, false positive signal response can be avoided, and the detection accuracy can be improved.

[0059] In a feasible implementation, when any one of the first detection result and the second detection result shows that mercury ions do not exist in the liquid to be detected, a detection conclusion that the liquid to be detected does not contain mercury ions is output.

[0060] In this technical solution, when any one of the first test result and the second test result shows that there are no mercury ions in the liquid to be tested, the detection conclusion that the liquid to be tested does not contain mercury ions is output, based on which the influence of interferences can be reduced, false positive signal responses can be avoided, and detection accuracy can be improved.

[0061] In a feasible embodiment, the step of obtaining the first detection result based on the plasma response of gold nanoparticles and mercury ions includes: adding AuNPs solution to the liquid to be detected and incubating for 30 minutes; adding working buffer solution to the solution; recording the color and Vis-NIR spectral changes of the liquid solution by an image acquisition device and an ultraviolet-visible spectrophotometer; and obtaining the first detection result based on the liquid color and Vis-NIR spectral changes.

[0062] In this technical solution, a method for obtaining a first detection result is further provided, by adding an AuNPs solution to the liquid to be detected and incubating for 30 minutes; adding a working buffer solution to the solution; recording the color and Vis-NIR spectral changes of the liquid solution by an image acquisition device and a UV-visible spectrophotometer; and obtaining a first detection result based on the changes in the liquid color and Vis-NIR spectral changes, which can improve the accuracy of the plasma response.

[0063] In a feasible implementation manner, the pH value of the working buffer solution is 7.4; the working buffer solution is a 0.02 M Tris-HCl buffer solution containing 0.1 M NaCl and 5 mM KCl.

[0064] In this technical solution, parameters of a working buffer are further provided. The pH value of the working buffer is 7.4. The working buffer solution is a 0.02 M Tris-HCl buffer solution containing 0.1 M NaCl and 5 mM KCl, which can further improve the accuracy of plasma response.

[0065] In a feasible implementation, the step of obtaining the first detection result based on the liquid color and Vis-NIR spectrum changes includes: when the absorbance ratio of the Vis-NIR spectrum at 650 nm to 530 nm is greater than or equal to 0.4, outputting that mercury ions are present; when the absorbance ratio of the Vis-NIR spectrum at 650 nm to 530 nm is less than 0.4, outputting that mercury ions are not present. Such a setting can make the determination of the first detection result more accurate.

[0066] In a feasible embodiment, the step of obtaining the second detection result based on the nanozyme response of the gold nanoparticles and mercury ions includes: adding H2O2 and TMB solution to the solution after completing the plasma response; recording the color of the liquid solution and the Vis-NIR spectrum changes again through the image acquisition device and the ultraviolet visible spectrophotometer; obtaining the second detection result based on the liquid color and Vis-NIR spectrum changes. Such a setting can improve the detection accuracy of the plasma response, that is, it can improve the accuracy of the second detection result.

[0067] In a feasible implementation, the step of obtaining a second detection result based on the change in liquid color and Vis-NIR spectrum includes: when the value at 652 nm of the Vis-NIR spectrum is greater than or equal to 0.5, outputting that mercury ions are present; when the value at 652 nm of the Vis-NIR spectrum is less than 0.5, outputting that mercury ions are present.

[0068] In this technical solution, a specific method for determining the second detection result is further provided, and such a setting can further improve the detection accuracy of the second detection result.

[0069] In a feasible embodiment, the mercury ion detection method further includes: preparing an AuNPs solution by reducing HAuCl4 with citric acid. Such a setting can improve the purity of the AuNPs solution, reduce the impurity content in the gold nanoparticles, and further ensure the detection accuracy. Example

[0070] The present application embodiment proposes a method for detecting mercury ions, comprising:

[0071] Step 101: adding gold nanoparticles to a liquid to be detected; obtaining a first detection result based on the plasma response of the gold nanoparticles and mercury ions;

[0072] Step 102: obtaining a second detection result based on the nanozyme response of the gold nanoparticles and mercury ions;

[0073] Step 103: Only when both the first detection result and the second detection result show the presence of mercury ions, output a detection conclusion that the liquid to be detected contains mercury ions.

[0074] The execution process of the mercury ion detection method may include the following steps:

[0075] 1. Preparation of AuNPs

[0076] Before the preparation of AuNPs, all glassware needed were first soaked in aqua regia, then rinsed thoroughly with ultrapure water and air-dried. For the preparation of AuNPs, 45 mL of ultrapure water, 2.5 mL of HAuCl4 (5 × 10 −3 M) solution and 2.5 mL of trisodium citrate (1.7 × 10 −2 M) solution was added to a 100 mL round-bottom flask equipped with a condenser. Subsequently, the mixed solution was stirred and heated under reflux at 100 ° C for 10 minutes, and the color of the mixed solution was observed to change from light yellow to wine red, indicating that AuNPs had been formed in the solution. Finally, the mixed solution was naturally cooled to room temperature to obtain the AuNPs product, which was stored at 4 ° C for subsequent sensing use.

[0077] 2. AuNPs to Hg 2+ Dual response feasibility study

[0078] 10 μL of aptamer DNA (2.1 μM) solution (DNA oligonucleotide sequence: 5′-TTCTTTCTTCCCCTTGTTTGTT-3′) was mixed with 20 μL of Hg2+ After the solution was incubated for 10 min, 300 µL of AuNPs solution was added and incubated for another 30 min. Subsequently, the working buffer (the working buffer solution has a pH of 7.4 and is a 0.02 M Tris-HCl buffer solution containing 0.1 M NaCl and 5 mM KCl) was added to the mixed solution for 1 min. The solution color and Vis-NIR spectral changes caused by the AuNPs plasma response were recorded using a digital camera and UV-visible spectrophotometer. Figure 2 As shown (a: AuNPs + ssDNA + NaCl; b: AuNPs + ssDNA + Hg 2+ + NaCl), the solution color was observed to change rapidly from wine red to gray-blue, and the characteristic absorption peak red-shifted from 530 nm to 670 nm. Figure 3 a and Figure 3 b ((a: AuNPs + ssDNA + NaCl; b: AuNPs + ssDNA + Hg 2+ + NaCl)), AuNPs were observed to aggregate significantly by transmission electron microscopy (TEM). 2+ A plasma response may be generated.

[0079] Continue to add 20 µL of H2O2 (0.75 M) and 20 µL of TMB (25 mM) solution to the above mixed solution for 7 minutes. Then, the solution color and Vis-NIR spectrum changes produced by the AuNPs nanozyme response were recorded again using a digital camera and UV-visible spectrophotometer. Figure 4 As shown (a to d are: H2O2+ TMB; Hg 2+ + H2O2+ TMB; AuNPs + ssDNA + NaCl + H2O2+ TMB; AuNPs + Hg 2+ + ssDNA + NaCl + H2O2 + TMB), the solution color was observed to change from gray-blue to bright blue, and an obvious characteristic absorption peak appeared at 650 nm, indicating that surface TMB was oxidized. Figure 5 As shown in the figure, the XPS spectrum of Hg 4f shows two Hg 0 4f 7 / 2 and Hg 0 4f 5 / 2 The relevant characteristic peaks indicate that Hg 2+ It may be reduced to Hg by trisodium citrate ligand on the surface of AuNPs 0The AuNPs were deposited on the surface of AuNPs in the form of monolayer or sub-monolayer to form gold amalgam, which significantly enhanced the peroxidase-like activity of AuNPs. 2+ Nanozyme responses can also be generated.

[0080] 3. AuNPs to Hg 2+ Research on Double Response Logical Judgment

[0081] Select different interfering substances (Ag + 、Ni 2+ 、Zn 2+ Mg 2+ , Mn 2+ 、Co 2+ , Ba 2+ , Cu 2+ 、Cd 2+ , Pb 2+ , Fe 2+ , Fe 3+ 、Ce 3+ 、Bi 3+ Cr 3+ 、Al 3+ 、F − Br − ,I − 、AsO2 − ,HAsO4 2− PO4 2− 、SO4 2− , S 2− 、SO3 2− , dopamine, melamine, kanamycin), and the solution color and Vis-NIR spectrum generated by the AuNPs' response to their plasma and nanozymes were recorded using a digital camera and a UV-visible spectrophotometer, respectively. Figure 6 a to Figure 6 As shown in Figure d, it can be seen that whether the AuNPs plasma response signal or the AuNPs nanozyme response signal is used alone, the proposed AuNPs colorimetric system is effective in accurately detecting Hg 2+ The sensing performance of all aspects is not ideal. 2+ In addition to being able to trigger two responses at the same time, other interfering substances can usually only trigger one of the response signals related to the AuNPs plasma and nanozyme characteristics, that is, interfering substances that trigger plasma response cannot trigger nanozyme response, and interfering substances that trigger nanozyme response cannot trigger plasma response.

[0082] Based on the observed phenomena, an AND logic gate with dual-channel response characteristics of AuNPs plasmon and nanozyme was constructed. Figure 7As shown in Figure a to Figure b, only when the plasma response signal and the nanozyme response signal are turned on at the same time, that is, the input value is (1,1), the output value is "1", and it is judged that the target Hg 2+ When only one of the two responses is turned on or both are not turned on, that is, when the input is (1,0), (0,1) or (0,0), the output value is "0", indicating that the sensor signal obtained belongs to the interference object. At this time, it is judged that there is no target object Hg 2+ .

[0083] like Figure 8 As shown, further A 650 / A 530 (ratio of absorbance at 650 nm to absorbance at 530 nm) = 0.4 and A 652 (absorbance at 652 nm) = 0.5 as the turn-on thresholds of the plasmon response and nanozyme response of the colorimetric sensing system, respectively. For the plasmon response, when A 650 / A 530 When it is greater than or equal to 0.4, the input value is 1. A 650 / A 530 When it is less than 0.4, the input value is 0; and for the nanozyme response, when A 652 When it is greater than or equal to 0.5, the input value is 1. A 652 When it is less than 0.5, the input value is 0. Fig. 9 As shown, according to this logical judgment, only the target object Hg 2+ The AuNPs plasmon response or nanozyme response can be triggered simultaneously, while other interferents can only trigger one of the responses or neither. 2+ The logical output value is 1 and can be accurately identified.

[0084] 4. AuNPs to Hg 2+ Study on the sensitivity of dual-response detection

[0085] Select different concentrations of Hg 2+ , the solution color and Vis-NIR spectra produced by the AuNPs in response to their plasmons and nanozymes were recorded using a digital camera and a UV-visible spectrophotometer, respectively.

[0086] like Fig.10 a to Fig.10 As shown in c, in the AuNPs colorimetric sensing system based only on plasma response, as Hg2+ As the concentration of α-hydroxy-1-(2-nitropropene)-2-nitropropene increases, the color of the reaction solution gradually changes from wine red to gray blue, and the SPR absorption peak gradually red-shifts from 530 nm to 670 nm. Through linear fitting, A 670 / A 530 With Hg in the range of 50 to 2500 nM 2+ The concentration shows a good linear relationship, and the linear equation is: A 670 / A 530 = 3.4185E−4 c + 0.2218 (R 2 = 0.9910), and the limit of detection (LOD) was calculated to be 45.8 nM based on three times the standard deviation above the blank (S / N = 3).

[0087] like Fig.11 a to Fig.11 As shown in c, in the AuNPs dual-response sensing system with the addition of TMB and H2O2, as Hg 2+ As the concentration of Hg increases, the color of the reaction solution gradually changes from purple to bright blue, and the TMBox characteristic absorption peak at 652 nm continues to increase. 2+ In the concentration range of 25 to 2500 nM A 652 It shows a good linear relationship, and the linear equation is A 652 = 1.6389E−4 c + 0.3474 (R 2 = 0.9954), and the calculated detection limit is 9.7 nM (S / N= 3). Compared with the sensing system based only on AuNPs plasma response, the AuNPs dual-response sensing system has better performance in detecting Hg 2+ The detection showed a lower LOD (about 4.7 times lower)

[0088] In the present invention, the terms "first", "second", and "third" are used for descriptive purposes only and should not be understood as indicating or implying relative importance; the term "plurality" refers to two or more, unless otherwise clearly defined. The terms "installed", "connected", "connected", "fixed", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; "connected" can be a direct connection or an indirect connection through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0089] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by terms such as “upper”, “lower”, “left”, “right”, “front” and “back” are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or unit referred to must have a specific direction, be constructed and operated in a specific orientation, and therefore, cannot be understood as a limitation on the present invention.

[0090] In the description of this specification, the description of the terms "one embodiment", "some embodiments", "specific embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0091] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for detecting mercury ions, characterized in that: include: Adding gold nanoparticles to the liquid to be tested; Obtaining a first detection result based on the plasma response of the gold nanoparticles and the mercury ions; Obtaining a second detection result based on the nanozyme response of the gold nanoparticles and the mercury ions; Construct an AND logic gate with dual-channel response characteristics of AuNPs plasmon and nanozyme; Outputting a detection conclusion that the liquid to be tested contains mercury ions only when both the first detection result and the second detection result show the presence of mercury ions; When any one of the first detection result and the second detection result shows that mercury ions do not exist in the liquid to be detected, outputting a detection conclusion that mercury ions do not exist in the liquid to be detected, so as to avoid a false positive signal response; The step of obtaining a first detection result based on the plasma response of the gold nanoparticles and the mercury ions comprises: 10 μL of aptamer solution with the aptamer DNA oligonucleotide sequence of 5′-TTCTTTCTTCCCCTTGTTTGTT-3′ was mixed with 20 μL of Hg 2+ After the solution was incubated for 10 min, 300 μL of AuNPs solution was added and incubated for another 30 min; Working buffer was added to the mixed solution. The pH of the working buffer solution was 7.

4. The working buffer solution was a 0.02 M Tris-HCl buffer solution containing 0.1 M NaCl and 5 mM KCl. The solution was reacted for 1 min. The solution color and Vis-NIR spectral changes generated by the AuNPs plasma response were recorded using a digital camera and UV-visible spectrophotometer. When the absorbance ratio at 650 nm to 530 nm in the Vis-NIR spectrum is greater than or equal to 0.4, the output contains mercury ions; When the absorbance ratio at 650 nm to 530 nm in the Vis-NIR spectrum is less than 0.4, the output does not contain mercury ions; The step of obtaining a second detection result based on the nanozyme response of the gold nanoparticles and mercury ions comprises: After the plasma response was completed, H2O2 and TMB solutions were added to the solution; Again, the color and Vis-NIR spectrum changes of the liquid solution are recorded by an image acquisition device and a UV-visible spectrophotometer; When the absorbance at 652 nm in the Vis-NIR spectrum is greater than or equal to 0.5, the output contains mercury ions; When the absorbance at 652 nm in the Vis-NIR spectrum is less than 0.5, the output contains mercury ions.

2. The mercury ion detection method according to claim 1, characterized in that: Also includes: AuNPs solution was prepared by reducing HAuCl4 with citric acid.

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