Molecular recognition material preparation method based on monatomic imprinting and molecular recognition method

Abstract

The invention relates to the technical field of material science and engineering, and discloses a preparation method of a molecular recognition material based on monatomic imprinting and a molecular recognition method, which can customize a recognition unit according to a specific structure of a to-be-detected molecule and remarkably improve the sensitivity and selectivity of molecular detection. The preparation method comprises the following steps: selecting a corresponding metal ion precursor according to the structural characteristics of a target molecule; dissolving a mixture of a target molecule and a metal ion precursor in an acidic aqueous solution; placing a carrier material in the acidic aqueous solution to form a reaction system comprising the solution and the carrier material; freezing the reaction system to a solid state; performing electrochemical reduction on the reaction system in a frozen state, so that metal ions derived from the metal precursor are reduced and loaded on the carrier material; and unfreezing and washing the carrier material subjected to electrochemical reduction to obtain the monatomic imprinting molecular recognition material.

Description

Technical Field

[0001] This application relates to the fields of materials science and engineering, and in particular to methods for preparing molecular recognition materials and molecular recognition methods. Background Technology

[0002] This section is intended to provide background or context for understanding the implementation of this application and is for reference only. It should not be construed as an admission by the applicant that this section pertains to prior art that was disclosed before the filing date of this application.

[0003] Molecular recognition is a crucial process for maintaining life in organisms, involving the organism's perception and response to the environment, from basic metabolic processes to higher immune responses. This recognition ability enables organisms to respond quickly and accurately to external factors, ensuring the stability and integrity of living systems. Molecular recognition technology plays a vital role in biosensing, diagnosis, therapy, and basic biological research.

[0004] Currently, common biomolecular recognition methods include antibodies, enzymes, aptamers, nucleic acids, and molecularly imprinted polymers (MIPs). Each of these methods has its own advantages and disadvantages.

[0005] 1. Antibodies possess high specificity and affinity, and are widely used in diagnostic testing and treatment. However, antibodies suffer from problems such as difficult preparation, high cost, poor stability, and poor reproducibility.

[0006] 2. Enzymes, as biological catalysts, can recognize specific substrates and accelerate chemical reactions. However, enzyme activity is easily affected by environmental conditions, and their preparation cost is relatively high, and they are prone to inactivation.

[0007] 3. Aptamers are single-stranded DNA or RNA molecules obtained through in vitro screening that can specifically bind to target molecules. Although aptamers have wide applications in biosensing, drug development, and molecular diagnostics, challenges remain regarding their stability and practicality in complex biological environments.

[0008] 4. Nucleic acid recognition technologies, such as polymerase chain reaction (PCR), use specific DNA sequences to detect specific RNA or DNA sequences. However, this method can be affected by the purity and integrity of nucleic acids in the sample.

[0009] 5. Molecularly imprinted polymers (MIPs) are a class of specially prepared polymers that can form cavities in their structure that match specific molecular shapes and functional groups. However, MIPs may face problems such as template molecule residue and non-specific adsorption.

[0010] In recent years, single-atom materials have been increasingly applied in analytical sensing due to their maximized atom utilization and customizable coordination environments. Single-atom materials refer to individual metal atoms highly dispersed on a support surface, possessing unique electronic structures and catalytic properties. However, due to the inherently high surface energy of their individual metal atoms, single-atom catalysts tend to aggregate into nanoclusters or nanoparticles at higher loading levels. Preparing low-loading single-atom materials to prevent aggregation often fails to achieve optimal sensing performance, thus reducing the sensitivity and selectivity of the sensor.

[0011] Furthermore, the reasons for the strong selectivity of existing single-atom materials are not yet fully understood, which limits their application in analytical detection. To achieve higher activity and selectivity in single-atom catalysts, it is necessary to conduct in-depth research on the relationship between metal atom types and coordination environments.

[0012] Currently, reported single-atom sensing technologies are mainly limited to detecting analytes with specific structural similarities, such as those with metal coordinating atoms (mainly nitrogen, oxygen, and sulfur) or those rich in π electrons (such as aromatic compounds). This limitation poses a challenge to the widespread application of single-atom materials in molecular recognition.

[0013] Therefore, the main challenge facing existing technologies is how to customize recognition units based on the specific structure of the analyte molecule to significantly improve detection sensitivity and selectivity, while simultaneously expanding the application range of single-atom materials in analytical detection. Solving this problem will contribute to the development of more efficient and accurate molecular recognition materials and methods, providing new technological support for fields such as biosensing, environmental monitoring, and medical diagnostics. Summary of the Invention

[0014] The purpose of this application is to provide a method for preparing molecular recognition materials based on single-atom imprinting and a molecular recognition method, which can customize recognition units according to the specific structure of the molecule to be tested, thereby significantly improving the sensitivity and selectivity of molecular detection.

[0015] This application discloses a method for preparing a molecular recognition material, including:

[0016] Select the appropriate metal ion precursor based on the structural characteristics of the target molecule;

[0017] The mixture of the target molecule and the metal ion precursor is dissolved in an acidic aqueous solution;

[0018] The carrier material is placed in the acidic aqueous solution to form a reaction system containing the solution and the carrier material;

[0019] The reaction system was frozen to a solid state;

[0020] In a frozen state, the reaction system is electrochemically reduced to reduce the metal ions derived from the metal precursor and load them onto the support material.

[0021] The carrier material, after electrochemical reduction, is thawed and washed to obtain a single-atom imprinted molecular recognition material.

[0022] In a preferred embodiment, the ratio of the metal ion precursor to the target molecule in the acidic aqueous solution is determined based on the number of coordinateable functional groups in the target molecule.

[0023] In a preferred embodiment, the electrochemical reduction is carried out at a temperature between -80°C and -20°C.

[0024] In a preferred embodiment, the electrodes of the electrochemical system are placed in the reaction system before the reaction system is frozen to a solid state;

[0025] In the step of freezing the reaction system to a solid state, the reaction system comprising the electrode, the solution, and the carrier material is frozen to a solid state.

[0026] In a preferred embodiment, after the washing step, the washed carrier material is further dried.

[0027] In a preferred embodiment, the step of dissolving the metal ion precursor and the target molecule in an acidic aqueous solution further includes promoting full coordination between the metal ions and the target molecule by ultrasonic stirring.

[0028] In a preferred embodiment, the carrier material is an electrode sheet or a powdered substance.

[0029] In a preferred embodiment, the electrochemical reduction stops when the charge reaches a predetermined charge amount, wherein the predetermined charge amount is determined based on the metal loading in the single-atom material.

[0030] This application also discloses a molecular recognition method, including:

[0031] The sample to be tested is brought into contact with a molecular recognition material prepared according to the method described above;

[0032] Detect the response signal of the molecular recognition material;

[0033] The presence or absence of the target molecule in the sample to be tested is determined based on the response signal, and / or the content of the target molecule in the sample to be tested is detected.

[0034] In a preferred embodiment, the detection response signal is performed via fluorescence analysis, electrochemical analysis, or photoelectric analysis.

[0035] In the embodiments of this application, highly selective single-atom imprinted molecular recognition materials can be prepared by selecting a metal ion precursor based on the target molecular structure, mixing the target molecule with the metal ion and dissolving it in an acidic solution, adding a support, freezing the mixture, and then performing electrochemical reduction under frozen conditions. This method allows for the customization of recognition units according to the specific structure of the analyte molecule, significantly improving detection sensitivity and selectivity, and expanding the application range of single-atom materials in analytical detection.

[0036] Furthermore, by determining the ratio of the metal ion precursor to the target molecule based on the number of coordinateable functional groups in the target molecule, it is possible to achieve single-atom multi-site, high-efficiency capture of the analyte molecule. This ratio ensures that the metal ion and the functional groups of the analyte molecule are fully coordinated, forming a stable imprint template.

[0037] Furthermore, by performing electrochemical reduction at temperatures between -78°C and -27°C, the reaction system can be kept in a frozen state, ensuring uniform distribution of metal ions and effective reduction loading onto the carrier material. This low-temperature condition helps improve the uniformity and stability of the imprint template.

[0038] Furthermore, ultrasonic stirring of the precursor solution can promote sufficient coordination between metal ions and target molecules, thereby improving the formation efficiency and stability of the imprinted template. This method ensures sufficient contact and reaction between metal ions and target molecules.

[0039] Furthermore, the electrochemical reduction process can be controlled by determining the predetermined charge amount based on the desired metal loading, allowing for precise regulation of the metal loading in single-atom materials. This method can optimize material performance and detection results.

[0040] Furthermore, by contacting the sample to be tested with the prepared molecular recognition material and detecting the response signal, high-sensitivity and high-selectivity detection of target molecules can be achieved. This method can accurately determine the presence of target molecules and may quantitatively detect their content.

[0041] The various technical features disclosed in the above-described invention, the various technical features disclosed in the following embodiments and examples, and the various technical features disclosed in the accompanying drawings can be freely combined to form various new technical solutions (all of which should be considered as having been recorded in this specification), unless such a combination of technical features is technically infeasible. For example, in one example, feature A+B+C is disclosed, and in another example, feature A+B+D+E is disclosed. Features C and D are equivalent technical means that serve the same function, and technically only one needs to be used; it is impossible to use both simultaneously. Feature E can be technically combined with feature C. Therefore, the solution A+B+C+D should not be considered as having been recorded because it is technically infeasible, while the solution A+B+C+E should be considered as having been recorded. Attached Figure Description

[0042] Figure 1 This is a schematic flowchart of the preparation method of the molecular recognition material according to the first embodiment of this application;

[0043] Figure 2 This is a schematic diagram illustrating the coordination relationship between glucose molecules and copper ions in an example of glucose detection using molecular imprinting according to an embodiment of this application.

[0044] Figure 3 This is a schematic diagram of an organic molecule used for controlling the interatomic distance using molecular imprinting, according to an embodiment of this application. Detailed Implementation

[0045] In the following description, many technical details are presented to help the reader better understand this application. However, those skilled in the art will understand that the technical solutions claimed in this application can be implemented even without these technical details and various variations and modifications based on the following embodiments.

[0046] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0047] The first embodiment of this application relates to a method for preparing a molecular recognition material, such as... Figure 1 As shown, the preparation method of this molecular recognition material includes:

[0048] In step 101, a suitable metal ion precursor is selected based on the structural characteristics of the target molecule. Generally, metal salts such as manganese chloride, ferric chloride, cobalt sulfate, nickel sulfate, copper sulfate, zinc sulfate, ruthenium chloride, potassium chloropalladium, cadmium chloride, potassium chloroiridium, potassium chloroplatinate, chloroauric acid, and bismuth nitrate can serve as metal precursors for manganese, iron, cobalt, nickel, copper, zinc, ruthenium, palladium, cadmium, iridium, platinum, gold, and bismuth, respectively. Different metal ions have different coordination characteristics; therefore, the selection of metal ion precursors needs to be optimized based on the specific functional groups of the target molecule.

[0049] Then, proceed to step 102, where the mixture of the target molecule and the metal ion precursor is dissolved in an acidic aqueous solution to obtain a precursor solution. Preferably, the dissolved acidic aqueous solution can be ultrasonically stirred to promote sufficient coordination between the metal ions and the target molecule.

[0050] Alternatively, a 0.5 mol / L dilute sulfuric acid solution can be used to prepare the solution. It is worth noting that, according to experimental evidence, protons (H... + In frozen solutions, sulfuric acid plays a crucial role in electron transfer, with the current density increasing significantly with increasing proton concentration. Therefore, dilute sulfuric acid solution is used as a precursor solution. Experimental data show that acidic solutions with a pH value less than 3 can be used as the acidic aqueous solution of this application. Preferably, sulfuric acid with a concentration greater than 0.001 mol / L can be used.

[0051] The preparation methods for different metal atoms are the same; the difference lies in the types and quantities of metal ions in the solution. Generally, the preferred methods are K₂PtCl₆ (2mM), HAuCl₄ (0.5mM), K₂PdCl₆ (0.2mM), CuSO₄ (4mM), and Bi(NO₃)₃·5H₂O (6mM). Special attention needs to be paid to the concentration ratio of the solution when preparing the precursor solution. Taking glucose molecules as an example, the glucose molecule has six hydroxyl groups, and research shows that hydroxyl groups coordinate well with copper ions. Therefore, the precursor solution should be glucose:copper sulfate solution = 1:6. The final result is as follows... Figure 2 As shown, six copper ions act like templates in molecular imprinting, anchoring glucose molecules within them. Only molecules that precisely meet all six anchoring sites can be accurately anchored by this single-atom imprint. This ratio was derived from extensive experimental data, ensuring that during the subsequent imprinting process, the metal ions can fully coordinate with the functional groups of the analyte molecule, thereby forming a stable imprint template.

[0052] The process then proceeds to step 103, where the support material is placed in the precursor solution to form a reaction system comprising the solution and the support material. Here, the reaction system refers to the entirety of the precursor solution and the support material, including the target molecule and the metal ion precursor in the precursor solution. If the electrode used for electrochemical reduction is also inserted into the solution and frozen into a solid state in step 104, the electrode for electrochemical reduction is also included in the reaction system. There are various ways to form the reaction system comprising the solution and the support material. For example, if the support material is in powder form, the powdered support material can be mixed into an acidic aqueous solution containing the dissolved metal precursor to form a mixed solution as the reaction system. Alternatively, if the support material is in sheet form, the sheet-like support material can be inserted into an acidic aqueous solution containing the dissolved metal precursor (there may be structures that fix the position of the support material), and the entire structure forms the reaction system. The support can be of various dimensions (zero-dimensional, one-dimensional, two-dimensional, three-dimensional) and forms, such as powder, granules, strips, sheets, etc.

[0053] The process then proceeds to step 104, where the reaction system is frozen to a solid state. Preferably, rapid freezing can be performed using a cryogenic coolant (e.g., liquid nitrogen or liquid helium). If the concentration of the precursor solution is sufficiently low, an electrically refrigerated device can also be used for freezing.

[0054] The process then proceeds to step 105, where the reaction system undergoes electrochemical reduction in a solid-state frozen state, reducing metal ions derived from the metal precursor and loading them onto the support material. Electrochemical reduction can be carried out at a temperature between -80°C and -20°C. Preferably, it is carried out at a temperature between -78°C and -27°C. Preferably, the electrochemical reduction process can be controlled by the amount of charge, i.e., the electrochemical reduction stops when the charge reaches a predetermined amount, which is determined based on the metal loading in the single-atom material. The magnitude of the charge controls the distribution density of single atoms on the support material. If the charge is small, the distribution of single atoms on the support material will be sparse; if the charge is large, the distribution of single atoms on the support material will be dense. However, when the charge exceeds an upper limit, the density will not increase further.

[0055] The process then proceeds to step 106, where the electrochemically reduced carrier material is thawed, washed, and dried to obtain the single-atom imprinted molecular recognition material. In some cases, if the single-atom imprinted molecular recognition material can operate under humid conditions, the drying step can be omitted.

[0056] Preferably, in one embodiment, before step 102, the target molecule and the metal ion precursor can be mixed and stirred and incubated to obtain a mixture, thereby allowing the target molecule and the metal ion precursor to be fully coordinated. Then, proceed to step 102.

[0057] Preferably, the ratio of the metal ion precursor to the target molecule in the acidic aqueous solution is determined based on the number of coordinateable functional groups in the target molecule. For example, the target molecule M has x type I functional groups, y type II functional groups, and z type III functional groups. Based on the characteristics of these functional groups, different metal ions can be selected for coordination: type I metal ions are best suited for coordination with type I functional groups, type II metal ions are best suited for coordination with type II functional groups, and type III metal ions are best suited for coordination with type III functional groups. Therefore, the coordination ratio can be:

[0058] Target molecule M: ​​Type I metal ion: Type II metal ion: Type III metal ion = 1:x:y:z

[0059] This ratio reflects the number of various functional groups in the target molecule and their optimal coordination ratio with the corresponding metal ions.

[0060] In practice, metal salts can be used as precursors. For example, a type I metal salt can be used to provide type I metal ions, a type II metal salt to provide type II metal ions, and a type III metal salt to provide type III metal ions. Assuming that each molecule of these metal salts provides only one desired metal ion, these components can be mixed in the following molecular weight ratio when preparing acidic aqueous solutions:

[0061] Target molecule M: ​​Type I metal salt: Type II metal salt: Type III metal salt = 1:x:y:z

[0062] This method can create a highly specific single-atom imprint for complex target molecules, where different metal atoms specifically coordinate with different parts of the target molecule. This multi-metal, multi-site coordination mode can significantly improve the specificity and sensitivity of molecular recognition.

[0063] In practical applications, the specific x, y, and z values ​​need to be determined based on the structural characteristics of the target molecule and may require experimental optimization to achieve the best recognition results. Furthermore, the potential interactions between different metal ions and metal salts, as well as their differences in behavior during electrochemical reduction, must be considered.

[0064] Preferably, in one embodiment, prior to step 104, the electrodes of the electrochemical system are placed in the reaction system, and then in step 104, the entire reaction system, including the electrodes, solution, and support material, is frozen to a solid state. For example, titanium dioxide electrode sheets can be used. To ensure a greater loading capacity, the electrode sheets are first placed in the prepared precursor solution and stirred for at least 8 hours. The purpose of stirring is to ensure that metal ions are uniformly distributed on the support surface, thereby improving the uniformity and stability of the imprinted template.

[0065] Optionally, in one embodiment, after freezing the reaction system containing the solution and the carrier material into a solid, electrodes for electrochemical reduction can be disposed on the surface of the solid. For example, if the carrier material is in powder form, it can be dissolved in an acidic aqueous solution to form a mixed solution, then frozen into a cuboid solid. Two surface electrodes can then be attached to opposite sides of the cuboid as the cathode and anode of the electrochemical reaction.

[0066] This embodiment utilizes the structure of the analyte molecule itself to prepare a single-atom recognition unit, which not only increases the single-atom loading but also allows for higher selectivity through a customized template. Compared to conventional non-customized single-atom preparation methods, this embodiment can detect any analyte based on its coordination environment, rather than being limited to the specific catalysis of active groups in the analyte by the active sites of a single atom, greatly expanding the application of single-atom materials in analytical detection.

[0067] To better understand the technical solution of this application, a specific example is provided below. The details listed in this example are mainly for ease of understanding and are not intended to limit the scope of protection of this application.

[0068] The following examples describe a method for preparing a single-atom imprinted molecular recognition material for detecting glucose and its application.

[0069] The selection of the metal ion precursor is crucial to the entire process. In this embodiment, copper sulfate (CuSO4) was chosen as the metal ion precursor. This choice is based on the fact that glucose molecules have six hydroxyl groups, and copper ions have a good coordination ability with hydroxyl groups. Glucose was selected as the target molecule, titanium dioxide (TiO2) electrode sheet was used as the support material, and 0.5 mol / L dilute sulfuric acid solution was used as the acidic aqueous solution.

[0070] Glucose and copper sulfate were then mixed in a 1:6 molar ratio and stirred and incubated to ensure that each glucose molecule could fully coordinate with 6 copper ions. The mixture was then dissolved in an acidic aqueous solution to obtain a precursor solution. Specifically, 1.8 g (10 mmol) of glucose and 15 g (60 mmol) of copper sulfate pentahydrate were weighed and dissolved in 100 mL of 0.5 mol / L dilute sulfuric acid solution.

[0071] The prepared solution was ultrasonically stirred at room temperature for approximately 12 hours to ensure adequate coordination between glucose and copper ions. The solution was kept out of light during stirring to prevent potential photochemical reactions.

[0072] The carrier material was then processed. A 5cm × 5cm titanium dioxide electrode sheet was immersed in the prepared solution and incubated with stirring at room temperature for 4 hours to allow the metal ion-target molecule complex to be uniformly distributed on the electrode surface.

[0073] Next, the reaction system was constructed. The treated titanium dioxide electrode sheet was placed in a polyethylene plastic cup, and two platinum plates were inserted as the working electrode and the counter electrode. The titanium dioxide electrode sheet was placed between the two platinum plates, with the front side facing the working electrode.

[0074] The reaction system was then subjected to freezing. It was completely immersed in liquid nitrogen for approximately 3 minutes to rapidly freeze. After removal, a small amount of deionized water was added to the surface, and the system was then placed back into liquid nitrogen for 5 minutes to ensure complete freezing.

[0075] Electrochemical reduction was then performed. The electrochemical reduction process was carried out in a cryogenic constant temperature bath at -78℃. The Chenhua electrochemical working system was used, with the constant potential set to -10V and the sensitivity to 1e. -1 The electrochemical reduction process is initiated, and the real-time charge level is monitored. The reduction process is stopped when the charge level reaches a predetermined value (60°C in this example). It is worth noting that the optimal charge level should be determined by subsequent photoelectric testing; there exists an optimal charge level that meets the testing requirements. Furthermore, there is a linear relationship between the charge level and the single-atom loading, which can be measured using inductively coupled plasma atomic emission spectrometry (ICP-AES).

[0076] The reaction mixture was then thawed, washed, and dried. Specifically, the reduced reaction system was removed from the cryogenic bath and allowed to thaw naturally at room temperature. The electrode was then removed and thoroughly rinsed with deionized water to remove unreacted precursors and glucose molecules. Finally, the electrode was dried in a nitrogen stream to obtain a titanium dioxide electrode loaded with copper single atoms, which is the desired single-atom imprinted molecular recognition material.

[0077] Photoelectrochemical testing can demonstrate the effectiveness of the single-atom imprinted molecular recognition materials prepared by this method. Fructose (an isomer of glucose), lactose (an analogue), and ascorbic acid (a common strong reducing agent) were used as interfering substances in the tests. Experiments showed that the single-atom imprinted material loaded with copper atoms only binds to glucose and produces a significant photocurrent response; this good selectivity proves the effectiveness of the single-atom imprinting method.

[0078] To further demonstrate the universality of this method, single-atom imprinting was performed using dithiols (-HS) and diamines (-NH2) separated by 2, 3, and 6 methylene groups, respectively. Their molecular structures are shown below. Figure 3As shown. Taking 1,2-ethanedithiol (with two methylene groups separated) as an example, gold can form a strong bond with the thiol group. Therefore, chloroauric acid (HAuCl4) was chosen as the metal ion precursor. A molar ratio of 1,2-ethanedithiol to chloroauric acid of 1:2 was prepared and dissolved in a 0.5 mol / L dilute sulfuric acid solution. The titanium dioxide electrode sheet to be prepared was then placed in the solution and stirred and incubated overnight. Photoelectric analysis revealed that the single-atom imprinted material only showed a good response to 1,2-ethanedithiol, while it did not respond to 1,3-propanedithiol (with three methylene groups separated) and 1,6-hexanedithiol (with six methylene groups separated), which also have thiol groups at both ends. On the other hand, in the case of 1,2-ethylenediamine (separated by two methylene groups), based on the good coordination ability of zinc with amino groups, zinc sulfate was used as the metal precursor, prepared at a ratio of 1,2-ethylenediamine:zinc sulfate = 1:2. The precursor solution was also dissolved in a 0.5 mol / L dilute sulfuric acid solution. Photoelectric analysis also revealed that the single-atom imprinted material only responded well to 1,2-ethylenediamine, but not to 1,3-propanediamine and 1,6-hexanediamine.

[0079] In summary, the single-atom imprinting method can be applied to control the interatomic spacing through precursor templates.

[0080] The second embodiment of this application relates to a molecular recognition method, including the following steps:

[0081] The sample to be tested is brought into contact with the molecular recognition material prepared in the first embodiment. For example, the prepared molecular recognition material can be brought into contact with blood to be tested in order to detect glucose molecules in the blood.

[0082] The response signal of molecular recognition materials is detected. Methods for detecting the response signal include fluorescence analysis, electrochemical analysis, or photoelectric analysis.

[0083] The presence and / or concentration of the target molecule in the sample are determined based on the response signal. In photoelectric testing, a response signal is only generated when the target molecule is present in the prepared imprint template. For example, in the case of glucose, only glucose within the detection linear range (a concentration of approximately 10 mmol / L in human plasma meets the testing requirements) will generate a photocurrent signal. Other molecules present in human plasma, such as ascorbic acid (approximately 400 μmol / L), glutathione (approximately 1.1 mmol / L), and interfering substances with similar structures, such as lactose (a disaccharide composed of glucose and galactose, approximately 15 μmol / L) and fructose (an isomer of glucose, 10 μmol / L), do not generate a response on the single-atom imprint material. Due to its good selectivity, it is used to determine glucose in actual samples such as human plasma or urine for blood glucose or urine glucose concentration monitoring.

[0084] In one example, an imprinted template of the target molecule can be prepared on a titanium dioxide photoelectrode using the method of the first embodiment. In use, the electrode is brought into contact with the sample to be tested, and simultaneously illuminated by a light source. If the sample contains a target molecule that matches the imprinted template, a photocurrent signal will be generated on the electrode. By detecting the presence of the photocurrent signal using electronic equipment, it can be determined whether the target molecule is present in the sample.

[0085] It should be noted that, in this disclosure, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one" does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element. In this application, if reference is made to performing an action based on an element, it means performing the action at least based on that element, including two cases: performing the action only based on that element, and performing the action based on that element and other elements. Expressions such as "multiple," "repeatedly," and "various" include two, two times, two kinds, and more than two, more than two times, and more than two kinds.

[0086] This specification includes combinations of various embodiments described herein. Individual references to embodiments (e.g., “one embodiment”, “some embodiments”, or “preferred embodiments”) do not necessarily refer to the same embodiment; however, these embodiments are not mutually exclusive unless indicated to be mutually exclusive or are readily apparent to those skilled in the art. It should be noted that the word “or” is used in a non-exclusive sense throughout this specification unless the context explicitly indicates or requires it.

[0087] All references to this application are considered to be incorporated in their entirety into the disclosure of this application so that they can serve as a basis for modifications if necessary. Furthermore, it should be understood that after reading the contents of this application, those skilled in the art can make various alterations or modifications to this application, and these equivalent forms also fall within the scope of protection claimed in this application.

Claims

1. A method for preparing a molecular recognition material, characterized in that, include: Select the appropriate metal ion precursor based on the structural characteristics of the target molecule; The mixture of the target molecule and the metal ion precursor is dissolved in an acidic aqueous solution; The carrier material is placed in the acidic aqueous solution to form a reaction system containing the solution and the carrier material; The reaction system was frozen to a solid state; In a frozen state, the reaction system is electrochemically reduced to reduce the metal ions derived from the metal precursor and load them onto the support material. The carrier material, after electrochemical reduction, is thawed and washed to obtain a single-atom imprinted molecular recognition material.

2. The method according to claim 1, characterized in that, The ratio of the metal ion precursor to the target molecule in the acidic aqueous solution is determined based on the number of coordinateable functional groups in the target molecule.

3. The method according to claim 1, characterized in that, The electrochemical reduction was carried out at a temperature between -80°C and -20°C.

4. The method according to claim 1, characterized in that, The electrodes of the electrochemical system are placed in the reaction system before the reaction system is frozen to a solid state; In the step of freezing the reaction system to a solid state, the reaction system comprising the electrode, the solution, and the carrier material is frozen to a solid state.

5. The method according to claim 1, characterized in that, Following the washing step, the washed carrier material is then dried.

6. The method according to claim 1, characterized in that, The step of dissolving the metal ion precursor and the target molecule in an acidic aqueous solution further includes promoting full coordination between the metal ions and the target molecule by ultrasonic stirring.

7. The method according to claim 1, characterized in that, The carrier material is an electrode sheet or a powdered substance.

8. The method according to any one of claims 1-7, characterized in that, The electrochemical reduction stops when the charge reaches a predetermined charge, wherein the predetermined charge is determined based on the metal loading in the single-atom material.

9. A molecular recognition method, characterized in that, include: The sample to be tested is brought into contact with the molecular recognition material prepared by the method according to any one of claims 1-8; Detect the response signal of the molecular recognition material; The presence or absence of the target molecule in the sample to be tested is determined based on the response signal, and / or the content of the target molecule in the sample to be tested is detected.

10. The method according to claim 9, characterized in that, The detection response signal can be achieved through fluorescence analysis, electrochemical analysis, or photoelectric analysis.

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