Cu-EDTA Detection Device and Method Based on Solid-State Nanopore Detection Technology

Abstract

This invention discloses a Cu-EDTA detection device and method based on solid-state nanopore detection technology, comprising: preparing an electrolyte solution; obtaining the analyte and preparing standard Cu-EDTA solutions of different concentrations based on the analyte; adding the electrolyte solution and standard Cu-EDTA solutions to both sides of a solid-state nanopore sensor in a fluid cell; applying a stable voltage to both sides of the nanopores of the solid-state nanopore sensor; acquiring current signals through a signal acquisition system; and obtaining the concentration of Cu-EDTA based on the analysis of the current signals. The detection method of this invention has the advantages of simple operation, high sensitivity, and fast response speed, and can be widely applied to online monitoring and risk assessment of pollutants in mining area water, providing scientific basis and technical support for mining area pollution control.

Description

Technical Field

[0001] This invention belongs to the field of rapid detection technology for environmental pollutants in mining areas, and particularly relates to a Cu-EDTA detection device and method based on solid-state nanopore detection technology. Background Technology

[0002] With the increasing severity of environmental pollution, heavy metal pollution, especially the complex formed by copper (Cu) and the organic ligand EDTA (ethylenediaminetetraacetic acid), has become a global concern. The Cu-EDTA complex exhibits high stability and water solubility, allowing it to persist in water bodies for extended periods, increasing the mobility and bioavailability of copper ions in the environment. This not only exacerbates water pollution but also increases its toxicity to aquatic organisms, thereby threatening ecological balance and human health.

[0003] Currently, detection technologies for heavy metal pollution face many challenges. Traditional analytical methods, such as chemical analysis, spectrometry, and electrochemical sensors, while capable of detecting the concentration of single metal ions, often struggle to provide sufficient sensitivity and real-time performance when dealing with complex metal-organic ligand complexes. In particular, the stability and low mobility of Cu-EDTA complexes make rapid and accurate quantitative analysis difficult using traditional methods. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention proposes a Cu-EDTA detection device and method based on solid-state nanopore detection technology, thereby resolving the issues present in the prior art.

[0005] To achieve the above objectives, the present invention provides a Cu-EDTA detection device based on solid-state nanopore detection technology, comprising:

[0006] Fluid cell, solid-state nanopore sensor, voltage application device, signal acquisition system, data processing unit;

[0007] The solid-state nanopore sensor is installed in the middle of the fluid pool;

[0008] A voltage application device is used to apply a stable voltage across the nanopores of the solid-state nanopore sensor to drive Cu-EDTA molecules through the nanopores;

[0009] A signal acquisition system is used to acquire current signals;

[0010] A data processing unit is used to obtain the concentration of Cu-EDTA based on the current signal.

[0011] Optionally, the pore diameter of the nanopore in the solid-state nanopore sensor is 1.5 nm.

[0012] Optionally, the fluid pool has grooves on both sides, and the grooves have guide holes. The positive electrode and negative electrode of the voltage application device are respectively inserted into the guide holes on both sides of the fluid pool.

[0013] This invention also provides a Cu-EDTA detection method based on solid-state nanopore detection technology, comprising:

[0014] Prepare electrolyte solutions; obtain analytes, and prepare standard Cu-EDTA solutions of different concentrations based on the analytes;

[0015] The electrolyte solution and the standard Cu-EDTA solution were respectively added to both sides of the solid-state nanopore sensor in the fluid cell;

[0016] A stable voltage is applied across the nanopores of a solid-state nanopore sensor, and a current signal is acquired through a signal acquisition system. The concentration of Cu-EDTA is then obtained based on the analysis of the current signal.

[0017] Optionally, the electrolyte solution is a mixture of ammonia and methanol, and the pH range of the electrolyte solution is 9.5-11.5.

[0018] Optionally, the process of acquiring the analyte includes:

[0019] After collecting tailings, the samples were naturally air-dried and pulverized. 0.01-0.02g of sample was weighed and leached with a solid-liquid ratio of 10:1. The leachate was then used as the analyte.

[0020] Optionally, the standard Cu-EDTA solution includes four concentrations: 0.6 mol / L, 0.8 mol / L, 1 mol / L, and 1.2 mol / L.

[0021] Optionally, the stable voltage is 110mV.

[0022] Optionally, the process of obtaining the concentration of Cu-EDTA includes: analyzing the amplitude change and translocation time of the current signal, performing statistical analysis on the amplitude change and translocation time to obtain the current characteristics and translocation signals of standard Cu-EDTA solutions of different concentrations; and obtaining the concentration of Cu-EDTA in the Cu-EDTA complex solution to be detected based on the current characteristics and translocation signals of standard Cu-EDTA solutions of different concentrations.

[0023] Compared with the prior art, the present invention has the following advantages and technical effects:

[0024] This invention proposes a method for detecting Cu-EDTA composite pollutants based on solid-state nanopore sensing technology. This technology achieves high-sensitivity, real-time monitoring of Cu-EDTA composites by precisely controlling the pore size and surface characteristics of the nanopores and combining this with the principle of resistance pulse sensing. The detection method of this invention has advantages such as simple operation, high sensitivity, and fast response speed, and can be widely applied to online monitoring and risk assessment of pollutants in mining area water, providing scientific basis and technical support for pollution control in mining areas. Attached Figure Description

[0025] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings:

[0026] Figure 1 This is a schematic diagram of the device according to an embodiment of the present invention;

[0027] Figure 2 The following is a schematic diagram of the sample measurement principle in an embodiment of the present invention: (a) is a schematic diagram of the nanopore detection device; (b) is a schematic diagram of the reference current; (c) and (d) are schematic diagrams of the blocking current generated by analytes of different sizes passing through the nanopore.

[0028] Figure 3 This is a current-time data graph corresponding to different detection concentrations in an embodiment of the present invention. Detailed Implementation

[0029] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0030] It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although a logical order is shown in the flowchart, in some cases the steps shown or described may be executed in a different order than that shown here.

[0031] Example 1

[0032] like Figure 1-3 As shown, this embodiment provides a Cu-EDTA detection device based on solid-state nanopore detection technology, comprising:

[0033] Fluid cell, solid-state nanopore sensor, voltage application device, signal acquisition system, data processing unit;

[0034] The solid-state nanopore sensor is installed in the middle of the fluid pool;

[0035] A voltage application device is used to apply a stable voltage across the nanopores of the solid-state nanopore sensor to drive Cu-EDTA molecules through the nanopores;

[0036] A signal acquisition system is used to acquire current signals;

[0037] A data processing unit is used to obtain the concentration of Cu-EDTA based on the current signal.

[0038] Furthermore, the pore diameter of the nanopore in the solid-state nanopore sensor is 1.5 nm.

[0039] Furthermore, the fluid pool has grooves on both sides, and the grooves have guide holes. The positive electrode and negative electrode of the voltage application device are respectively inserted into the guide holes on both sides of the fluid pool.

[0040] Specifically, a solid-state nanopore sensor with a pore size range of 1.5 nm is used to detect the current blocking characteristics of Cu-EDTA complexes;

[0041] A pressure application device is used to apply a voltage of 110mV across the nanopores to drive Cu-EDTA molecules through the nanopores;

[0042] The signal acquisition system is used to record the changes in current amplitude and displacement time as the current passes through the nanopore in real time.

[0043] The data processing unit is used to statistically analyze the detected current signal, generate a translocation time-amplitude scatter plot, a translocation time frequency distribution plot, and a blocking amplitude frequency distribution plot, and extract quantitative information on Cu-EDTA concentration using a Gaussian fitting method.

[0044] The pore size of the solid-state nanopores is precisely controlled within the range of 1.5 nm, enabling highly sensitive detection of Cu-EDTA complexes. A voltage application device, by applying a voltage of 110 mV, can create a stable electric field within the nanopores, ensuring the effective passage of Cu-EDTA molecules and generating a blocking current.

[0045] Figure 1 (d) is a Faraday shielded box, in which the nanopore sensor is fixed. Figure 1 (e) The fluid pools shown in the figure are divided into two independent fluid pools by the nanopore sensor, with the nanopores on the nanopore sensor becoming the only channels within the fluid pools. Figure 1 (b) The power supply shown is used to apply electrical signals to both sides of the nanopore sensor;

[0046] Figure 1 The data processing module shown in (a) is used for... Figure 1In the middle (c) patch clamp amplifier (signal acquisition system), electrical signals from the nanopore sensor are acquired to determine the reference current and time current map.

[0047] In the design of solid-state nanopore sensor chips or test cells, a groove is created at each end of the cell for adding liquid and inserting electrodes, ensuring that the solution completely submerges the electrode surface. The groove typically forms a closed or semi-closed space with the sensor surface, where liquid accumulates and connects to the other side through a nanopore in the center of the sensor. Guide holes are created on the sidewalls or bottom of the grooves to allow electrodes or wires to be inserted into the solution from the outside, immersing the electrode tips in the solution. These guide holes are used to fix the main working electrode or reference electrode; auxiliary electrodes are also present in the grooves. The working electrode is inserted near the nanopore for signal detection; the counter / auxiliary electrode is located in the groove on the other side, completing the circuit.

[0048] This embodiment also provides a Cu-EDTA detection method based on solid-state nanopore detection technology, including:

[0049] Prepare electrolyte solutions; obtain analytes, and prepare standard Cu-EDTA solutions of different concentrations based on the analytes;

[0050] The electrolyte solution and the standard Cu-EDTA solution were respectively added to both sides of the solid-state nanopore sensor in the fluid cell;

[0051] A stable voltage is applied across the nanopores of a solid-state nanopore sensor, and a current signal is acquired through a signal acquisition system. The concentration of Cu-EDTA is then obtained based on the analysis of the current signal.

[0052] Furthermore, the electrolyte solution is a mixture of ammonia and methanol, and the pH value of the electrolyte solution is in the range of 9.5-11.5.

[0053] Furthermore, the process of acquiring the analyte includes:

[0054] After collecting tailings, the samples were naturally air-dried and pulverized. 0.01-0.02g of sample was weighed and leached with a solid-liquid ratio of 10:1. The leachate was then used as the analyte.

[0055] Furthermore, the standard Cu-EDTA solution includes four concentrations: 0.6 mol / L, 0.8 mol / L, 1 mol / L, and 1.2 mol / L.

[0056] Furthermore, the stable voltage is 110mV.

[0057] Furthermore, the process of obtaining the concentration of Cu-EDTA includes: analyzing the amplitude change and translocation time of the current signal, performing statistical analysis on the amplitude change and translocation time to obtain the current characteristics and translocation signals of standard Cu-EDTA solutions of different concentrations; and obtaining the concentration of Cu-EDTA in the Cu-EDTA complex solution to be detected based on the current characteristics and translocation signals of standard Cu-EDTA solutions of different concentrations.

[0058] Specifically, the Cu-EDTA sample solution to be tested is added to the fluid cell of the device; wherein the concentration of the Cu-EDTA sample solution is 0.6 mol / L, 0.8 mol / L, 1 mol / L, or 1.2 mol / L. The specific solution is prepared according to experimental procedures, ensuring that the Cu-EDTA solution is in full contact with the electrodes on both sides of the fluid cell.

[0059] The fluid cell is a cavity divided into two parts by a solid-state nanopore sensor. One side serves as the "reference or electrolyte side" (e.g., only an electrolyte solution is added), and the other side serves as the "analyte side" (the analyte or a solution containing the analyte is added). The solid-state nanopore facilitates the exchange of matter or signals. In this embodiment, the response of the nanopore sensor under different concentrations of Cu-EDTA solution is studied. The solution concentration is changed on the "electrolyte side" or "analyte side," i.e., Cu-EDTA concentrations of 0.6 mol / L, 0.8 mol / L, 1 mol / L, and 1.2 mol / L are added to the groove on that side; while the other side (which may be the control side) is kept at 0 mol / L Cu-EDTA or pure electrolyte.

[0060] By applying a voltage of 110 mV across the solid nanopores of the device, Cu-EDTA complex molecules are forced to pass through the nanopores. The current changes during this process are affected by the blocking effect of the complex, generating a translocation signal. The electric field between the electrodes in the fluid cell and the nanopores drives Cu-EDTA molecules through the channels, producing changes in the current amplitude.

[0061] The current change (blocking current amplitude ΔI) and translocation time Δt during the passage through the nanopore are monitored and recorded in real time, and the data are recorded through a patch clamp amplifier and signal acquisition system connected to a computer.

[0062] Based on the measured IV current-voltage curves, the Cu-EDTA concentration was calculated using a fitting method. Statistical analysis of the current amplitude and translocation time yielded the current characteristics and translocation signals of Cu-EDTA solutions at different concentrations. Results for different detection concentrations are shown below. Figure 3 As shown.

[0063] The concentration of the Cu-EDTA sample to be tested is determined by comparing the translocation signal of the standard concentration solution with the signal of the actual sample solution.

[0064] The device absorbs the waste liquid formed after nanopore detection through its absorption layer.

[0065] Solid-state nanopores are thin film structures with nanoscale pore sizes. By precisely controlling the pore size and surface chemical properties, selective recognition and detection of specific molecules or complexes can be achieved. When a Cu-EDTA complex passes through a nanopore, its volume, charge, and shape characteristics generate a brief current-blocking signal within the pore. By recording the amplitude, duration, and frequency of these blocking signals, the concentration, size distribution, and motion behavior of the Cu-EDTA complex can be obtained.

[0066] Solid-state nanopore detection is based on the principle of resistance pulse sensing. When charged particles (such as Cu-EDTA complexes) in solution pass through a nanopore under the drive of an electric field, they temporarily partially impede the flow of ions within the pore, causing a transient change in the detection current. This current change directly reflects the physicochemical properties of the particles (such as size, charge, and shape). By analyzing these properties, highly sensitive quantitative detection of target complexes can be achieved. Compared to traditional sensors, solid-state nanopores not only possess high stability and long lifetime but also adapt to complex environmental conditions and exhibit good compatibility with microfluidics and semiconductor technologies, facilitating miniaturization and mass production.

[0067] By combining resistance pulse sensing technology, solid-state nanopore sensors can monitor the concentration changes of Cu-EDTA complexes in real time, providing high-sensitivity and high-precision technical support for the dynamic monitoring of environmental pollution. This technological breakthrough provides a new method for the accurate detection of heavy metal pollution and is expected to promote a comprehensive improvement in online pollutant monitoring and environmental risk assessment.

[0068] The above are merely preferred embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for quantitatively detecting Cu-EDTA in tailings based on solid-state nanopore detection technology, characterized in that, The detection is performed by using a device composed of a fluid cell, a solid-state nanopore sensor, a voltage applying device, and a signal acquisition system. The solid-state nanopore sensor is installed at the middle position of the fluid cell, and the nanopore has a pore diameter of 1.5 nm. The solid-state nanopore sensor is used to detect the current blocking characteristic value of the Cu-EDTA complex. The method comprises the following steps: An electrolyte solution is prepared, which is a mixture of ammonia and methanol, and the pH range is 9.5-11.

5. The test object is obtained, and different concentrations of Cu-EDTA standard solution are prepared based on the test object. The electrolyte solution and the Cu-EDTA standard solution or test object are added to both sides of the solid-state nanopore sensor in the fluid cell. The voltage applying device applies a voltage of 110 mV across the nanopore of the solid-state nanopore sensor to drive the Cu-EDTA molecules through the nanopore. The signal acquisition system monitors and records the blocking current amplitude ΔI and translocation time Δt in real time. According to the measured I-V current-voltage curve, the Cu-EDTA concentration is calculated by using a fitting method. Through statistical analysis of the current amplitude and translocation time, the current characteristics and translocation signals of different concentrations of Cu-EDTA standard solution are obtained. The translocation signals of the Cu-EDTA standard solution are compared with the signals of the actual sample solution to determine the concentration of the Cu-EDTA sample to be detected.

2. The method of claim 1, wherein, The fluid cell is provided with grooves on both sides, and the grooves are provided with guide holes. The positive electrode and the negative electrode of the voltage applying device are respectively inserted into the guide holes on both sides of the fluid cell.

3. The method of claim 1, wherein, The process of obtaining the test object comprises: After collecting the tailings, natural air drying and crushing treatment are performed. 0.01-0.02 g of sample is weighed, and the sample is oscillated and leached at a solid-liquid ratio of 10:

1. The leaching liquid is used as the test object.

4. The method of claim 1, wherein, The Cu-EDTA standard solution comprises four concentrations of 0.6 mol / L, 0.8 mol / L, 1 mol / L, and 1.2 mol / L.

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