Preparation and application of a hollow molecularly imprinted polymer

Abstract

The present application relates to a kind of preparation and application of hollow molecular imprinting polymer, first preparation adsorption, strong, specific surface area of magnetic composite microporous network adsorption material, then through HF etching, synthesis hollow microporous network adsorption material, finally through surface molecular imprinting to obtain hollow molecular imprinting polymer adsorption material, the hollow molecular imprinting polymer prepared can realize the selective adsorption and efficient enrichment of food and environmental pollutants.Due to its larger specific surface area, stronger hydrophobicity and other advantages, as harmful substance adsorption material has great potential.Ensure its stable application in complex food matrix, and then realize the selective enrichment and convenient control of target pollutants.

Description

Technical Field

[0001] This invention belongs to the field of materials technology, and in particular relates to the preparation and application of a hollow molecularly imprinted polymer. Background Technology

[0002] Food safety is a crucial factor in safeguarding human life and health, and food testing technology is the technological support that protects people's lives. Therefore, rapidly improving food testing technology, enhancing food safety awareness, and rigorously conducting food testing are of paramount importance in creating a healthy and safe food environment for the public.

[0003] Molecularly imprinted polymers (MIPs) are selective functional polymer materials. Using a target compound as a template molecule, they mimic the molecular recognition interaction between antigens and antibodies, exhibiting selective recognition capabilities for the template molecule. In recent years, due to their advantages such as good affinity, high selectivity, strong anti-interference ability, and long lifespan, they have been widely used for the specific recognition of target molecules in food. Microporous organic network materials (MONs) are emerging microporous materials composed of aromatic alkynes and halides. Prepared MONs possess high pore strength, but this strength mainly comes from the surface pores, while most of the internal pores are inaccessible and therefore cannot function effectively. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides a method for preparing and applying hollow molecularly imprinted polymers.

[0005] The technical solution adopted in this invention is: a method for preparing hollow molecularly imprinted polymers, which involves preparing magnetic composite microporous network adsorbent materials, synthesizing hollow microporous network adsorbent materials through HF etching, and then obtaining hollow molecularly imprinted polymer adsorbent materials through surface molecular imprinting.

[0006] Preferably, the specific steps include:

[0007] Step 1: Prepare magnetic composite microporous organic framework materials using an in-situ growth method;

[0008] Preparation of magnetic Fe3O4: FeCl3·6H2O, anhydrous sodium acetate, and ethylene glycol were mixed and reacted hydrothermally at 200℃. The product was washed and dried to obtain magnetic Fe3O4.

[0009] Preparation of magnetic Fe3O4@SiO2: Take 1.0g of magnetic Fe3O4, add 200mL of HCl, sonicate, rinse the product and add 80mL of ultrapure water, 320mL of ethanol and 5mL of ammonia, sonicate again; then add 1mL of TEOS, stir mechanically, collect the product with a magnet to obtain magnetic Fe3O4@SiO2.

[0010] Preparation of magnetic Fe3O4@SiO2@UiO-66-NH2: 150 mg of magnetic Fe3O4@SiO2 was taken, 300 mg of zirconium chloride (IV), 75 μL of water, and 30 mL of LDMF were added and stirred. 2-Aminoterephthalic acid was added and stirred to dissolve. The reaction was carried out hydrothermally at 120 °C. After the reaction was completed, the brown-black magnetic microspheres were collected, washed and dried to obtain magnetic Fe3O4@SiO2@UiO-66-NH2.

[0011] Preparation of magnetic Fe3O4@SiO2@UiO-66-NH2@MON: Take 200mg Fe3O4@SiO2@UiO-66-NH2, add 15mL toluene, 15mL triethylamine and catalyst, disperse completely and then mechanically stir at 90℃ for 0.5h. Add 50mg tetrakis(4-ethynylphenyl)methane and 80mg 1,4-diiodobenzene, heat at 90℃ for 6h. After the reaction is complete, collect the product with a magnet, wash and dry to obtain the magnetic composite microporous network adsorbent material Fe3O4@SiO2@UiO-66-NH2@MON;

[0012] Step 2: Synthesize hollow microporous network adsorbent material by HF etching; Take 100.0 mg Fe3O4@SiO2@UiO-66-NH2@MON, add 10 ml HF (5%) and react for 15 min. After washing and drying, obtain hollow microporous network adsorbent material HMON.

[0013] Step 3: Obtain hollow molecularly imprinted polymer adsorbent material through surface molecular imprinting; add 1 mmol DT to a mixture of 25 mL acetonitrile and 5 mL water and mix well. Add functional monomer (APTES), crosslinking agent (TEOS) and ammonia water to the system in a ratio of 1:4:9; after mixing evenly, add 3 mL HMON dispersed in acetonitrile; remove oxygen from the reaction system, stir overnight at room temperature, and the resulting precipitate is the hollow molecularly imprinted polymer HMON@MIP.

[0014] Preferably, the catalyst used in step one for preparing magnetic Fe3O4@SiO2@UiO-66-NH2@MON is 3.4 mg of bis(triphenylphosphine)palladium(II) chloride and 1.0 mg of cuprous iodide.

[0015] Preferably, the drying temperature is 50-60℃.

[0016] Preferably, in step three, the product obtained by stirring overnight is washed with methanol and water, and then eluted with a Soxhlet extractor, the eluent consisting of acetone and acetic acid (9:1, v / v).

[0017] Hollow molecularly imprinted polymers were prepared by a method for preparing hollow molecularly imprinted polymers.

[0018] Application of hollow molecularly imprinted polymers in the adsorption or detection of food or environmental pollutants.

[0019] Preferably, the obtained hollow molecularly imprinted polymer material is placed in the target solution to achieve adsorption or enrichment of pollutants.

[0020] Preferably, the hollow molecularly imprinted polymer after adsorption can be used again for the adsorption or enrichment of pollutants after being eluted with an eluent.

[0021] The advantages and positive effects of this invention are: the hollow molecularly imprinted polymer prepared by this method has uniform porosity, large specific surface area, and stable chemical properties, and has a significant and specific adsorption capacity for target pollutants; by providing the optimal reaction ratio and reaction conditions, the hollow structure of the material greatly increases the density of imprinted sites, thus improving the adsorption efficiency, and the hollow molecularly imprinted polymer obtained by the reaction has the best adsorption performance.

[0022] Hollow molecularly imprinted polymers can efficiently adsorb and enrich hazardous substances in food. The hollow microporous organic material core enhances the hydrophobicity of the material surface and interior, making it more stable in humid environments and better able to function in organic solvents. It is suitable for the adsorption and enrichment of various food contaminants, opening up new avenues for the detection of hazardous substances in food. It has important pioneering significance for further strengthening the monitoring and control of hazardous substances in food and promoting the application of analytical chemistry methodologies based on advanced functional materials in food safety and human health sciences. Attached Figure Description

[0023] Figure 1 Transmission electron microscopy images and dynamic light scattering analysis of hollow microporous network adsorbent materials and molecularly imprinted polymers;

[0024] Figure 2 Evaluation of the specificity of hollow molecularly imprinted polymer adsorbent materials;

[0025] Figure 3 To evaluate the repeatability of hollow molecularly imprinted polymer adsorbent materials. Detailed Implementation

[0026] The embodiments of the present invention will now be described with reference to the accompanying drawings.

[0027] This invention relates to the preparation and application of a hollow molecularly imprinted polymer. First, a magnetic composite microporous network adsorbent material with strong adsorption and a large specific surface area is prepared. Then, a hollow microporous network adsorbent material is synthesized through HF etching. Finally, a hollow molecularly imprinted polymer adsorbent material is obtained through surface molecular imprinting. The prepared hollow molecularly imprinted polymer can achieve selective adsorption and efficient enrichment of food and environmental pollutants. Due to its larger specific surface area and stronger hydrophobicity, it has great potential as an adsorbent material for harmful substances. Ensuring its stable application in complex food matrices will enable the selective enrichment and convenient control of target pollutants.

[0028] As researchers gain a deeper understanding of the growth mechanisms and microstructures of nanocrystals, hollow nanomaterials have become a hot topic in modern nanoscience research. To enhance adsorption capacity while maximizing the utilization of internal pores, novel hollow molecularly imprinted polymer materials have been developed. These materials exhibit enhanced hydrophobicity on both the surface and interior, resulting in higher stability in humid environments and better performance in organic solvents. They overcome the influence of food matrices on detection results, improve the selectivity of materials for target pollutants, and expand the applications of hollow materials. This has a positive impact on improving environmental hygiene and food safety monitoring, and provides important guidance and social value for promoting the development of efficient detection and evaluation methods for hazardous substances and the effective regulation of food contaminants.

[0029] This invention aims to, for the first time, etch a magnetic microporous organic network composite material to obtain a hollow microporous network adsorbent material, and then, through molecular imprinting, obtain a hollow molecularly imprinted polymer. This material is then introduced into the field of food science research, significantly improving its hydrophobicity and selectivity, and enhancing its adsorption efficiency and reproducibility. This enables convenient pretreatment and selective enrichment of target pollutants. A novel hollow microporous network adsorbent material with a hollow structure was constructed using a simple hard template method, and a novel hollow molecularly imprinted polymer was ultimately obtained through molecular imprinting. This material exhibits a typical hollow structure, with the core of magnetic Fe3O4 microspheres encapsulated by metal-organic framework (MOF) crystals. The microporous organic network is then introduced onto the surface of the MOF via a Sonogashira coupling reaction, and finally, the magnetic MOF is etched using hydrofluoric acid. The resulting hollow molecularly imprinted polymer adsorbent material achieves selective adsorption and efficient enrichment of food and environmental pollutants. Combined with high-performance liquid chromatography (HPLC) or gas chromatography (GC), target pollutants in complex matrix samples can be enriched and determined.

[0030] The specific preparation method is as follows:

[0031] Step 1: Prepare magnetic composite microporous organic framework materials with strong adsorption and large specific surface area using the in-situ growth method;

[0032] Preparation of magnetic Fe3O4: FeCl3·6H2O, anhydrous sodium acetate, and ethylene glycol were mixed and stirred for 60 minutes, then transferred to a Teflon-lined hydrothermal reactor and heated at 200°C for 8 hours. After the reaction was completed and cooled to room temperature, the mixture was washed four times with ultrapure water. Then, it was vacuum dried at 60°C for 12 hours, and the black magnetic powder product was collected.

[0033] Preparation of magnetic Fe3O4@SiO2: Take 1.0 g of magnetic Fe3O4 obtained in step (1), add 200 mL of HCl, sonicate for 10 min, and then rinse three times with ultrapure water. Add 80 mL of ultrapure water, 320 mL of ethanol, and 5 mL of ammonia, and sonicate for 10 min. Then add 1 mL of TEOS and stir mechanically for 12 hours. Collect the obtained product with a magnet and rinse four times alternately with ultrapure water and ethanol.

[0034] Preparation of magnetic Fe3O4@SiO2@UiO-66-NH2: 150 mg of the magnetic Fe3O4@SiO2 obtained in step (2) was added to 300 mg of zirconium chloride (IV), 75 μL of water, and 30 mL of LDM, and stirred for 15 min. Then, 2-aminoterephthalic acid was added and stirred until completely dissolved. The solution was transferred to a Teflon-lined hydrothermal reactor and heated at 120 °C for 24 hours. After cooling to room temperature, the brown-black magnetic microspheres were collected and washed several times with ultrapure water. Finally, the product was dried under vacuum at 60 °C for 12 hours.

[0035] Preparation of magnetic Fe3O4@SiO2@UiO-66-NH2@MON: Take 200 mg of Fe3O4@SiO2@UiO-66-NH2 obtained in step (3), add 15 mL of toluene, 15 mL of triethylamine and an appropriate amount of catalyst, and sonicate for 30 min. The catalyst and dosage are 3.4 mg of bis(triphenylphosphine)palladium(II) chloride and 1.0 mg of cuprous iodide. After complete dispersion, mechanically stir at 90 °C for 30 min, add 50 mg of tetra(4-ethynylphenyl)methane and 80 mg of 1,4-diiodobenzene, and continue heating at 90 °C for 6 hours. After the reaction system is cooled to room temperature, collect the product with a magnet, wash five times with dichloromethane and methanol, and vacuum dry at 50 °C. The resulting brownish-black powder is the magnetic composite microporous network adsorbent material Fe3O4@SiO2@UiO-66-NH2@MON.

[0036] Step 2: Synthesize hollow microporous network adsorbent material by HF etching; take 100.0 mg of Fe3O4@SiO2@UiO-66-NH2@MON, add 10 ml of HF (5%) and react for 15 min. After washing five times with ethanol and water, dry under vacuum at 50℃. The resulting black powder is the hollow microporous network adsorbent material HMON.

[0037] Step 3: Obtaining hollow molecularly imprinted polymer adsorbent material through surface molecular imprinting; 1 mmol DT was added to a mixture of 25 mL acetonitrile and 5 mL water, and stirred with a magnetic stirrer until completely dissolved. Next, functional monomers (APTES), crosslinking agents (TEOS), and ammonia were mixed into the system in different proportions, preferably with a molar ratio of 1:4:9. After thorough mixing, 3 mL of HMON dispersed in acetonitrile was added. Subsequently, nitrogen gas was continuously purged through the entire reaction system for 15 minutes to remove oxygen. Finally, the flask was sealed and stirred overnight at room temperature. The resulting precipitate was washed three times with methanol and water. Then, it was eluted using a Soxhlet extraction apparatus. The eluent consisted of acetone and acetic acid (9:1, v / v). The resulting solid was the hollow molecularly imprinted polymer HMON@MIP.

[0038] The prepared hollow molecularly imprinted adsorbent material exhibits excellent particle size uniformity and significant specificity in adsorbing target pollutants. Furthermore, the hollow structure greatly increases the density of imprinted sites, thus improving adsorption efficiency. Simultaneously, the hollow microporous organic core enhances the hydrophobicity of both the material's surface and interior, resulting in higher stability in humid environments and better performance in organic solvents. This makes it suitable for the adsorption and enrichment of various food contaminants.

[0039] Previously reported porous network adsorbent materials, such as metal-organic frameworks and hypercrosslinked polymers, suffer from drawbacks such as poor stability, cumbersome synthesis processes, and inadequate adsorption capacity, limiting their practical applications. The hollow microporous network adsorbent material prepared in this invention possesses advantages such as high porosity, large specific surface area, and good chemical stability. It can fully leverage the high adsorption efficiency of porous materials while ensuring stable application in complex food matrices, thereby achieving efficient enrichment and convenient control of target pollutants.

[0040] By combining high-performance liquid chromatography or gas chromatography, target pollutants in complex matrix samples can be enriched and determined.

[0041] The present invention will now be described with reference to the accompanying drawings. Experimental methods not specifically described in terms of operation steps are performed in accordance with the corresponding product manuals. Unless otherwise specified, the instruments, reagents, and consumables used in the embodiments can be purchased from commercial companies.

[0042] Example 1: Preparation of hollow molecularly imprinted polymers

[0043] First, an in-situ growth method was used to prepare a magnetic composite microporous network material with strong adsorption and large specific surface area.

[0044] Preparation of magnetic Fe3O4: 27 g FeCl3·6H2O, 57.5 g anhydrous sodium acetate, and 500 mL ethylene glycol were mixed and stirred for 60 minutes. The mixture was then transferred to a Teflon-lined hydrothermal reactor and heated at 200 °C for 8 hours. After the reaction was complete and cooled to room temperature, the product was washed four times with ultrapure water. It was then vacuum dried at 60 °C for 12 hours, and the resulting black magnetic powder was collected.

[0045] Preparation of magnetic Fe3O4@SiO2: Take 1.0 g of the magnetic Fe3O4 obtained in the previous step, add 200 mL of HCl (0.1 mol / L), sonicate for 10 min, and then wash three times with ultrapure water. Add 80 mL of ultrapure water, 320 mL of ethanol, and 5 mL of ammonia (concentration 25–28%), and sonicate for 10 min. Then add 1 mL of LTEOS and mechanically stir for 12 hours. The obtained product is collected with a magnet and washed four times alternately with ultrapure water and ethanol.

[0046] Preparation of magnetic Fe3O4@SiO2@UiO-66-NH2: 150 mg of the magnetic Fe3O4@SiO2 obtained in the previous step was added to 300 mg of zirconium(IV) chloride, 75 μL of water, and 30 mL of LDM, and stirred for 15 min. Then, 235 mg of 2-aminoterephthalic acid was added and stirred until completely dissolved. The solution was transferred to a Teflon-lined hydrothermal reactor and heated at 120 °C for 24 h. After cooling to room temperature, the brown-black magnetic microspheres were collected and washed several times with ultrapure water. Finally, the product was dried under vacuum at 60 °C for 12 h.

[0047] Preparation of magnetic Fe3O4@SiO2@UiO-66-NH2@MON: 200 mg of Fe3O4@SiO2@UiO-66-NH2 was added to 15 mL of toluene, 15 mL of triethylamine, 3.4 mg of bis(triphenylphosphine)palladium(II) dichloride, and 1.0 mg of cuprous iodide. The mixture was then sonicated for 30 min. After complete dispersion, the mixture was mechanically stirred at 90 °C for 30 min. 50 mg of tetrakis(4-ethynylphenyl)methane and 80 mg of 1,4-diiodobenzene were added, and the mixture was heated at 90 °C for 6 hours. After cooling the reaction system to room temperature, the product was collected using a magnet, washed five times with dichloromethane and methanol, and dried under vacuum at 50 °C. The resulting brownish-black powder was the magnetic composite microporous network adsorbent material Fe3O4@SiO2@UiO-66-NH2@MON.

[0048] Hollow microporous network adsorbent material was synthesized by HF etching. 100.0 mg of Fe3O4@SiO2@UiO-66-NH2@MON was added to 10 ml of HF (5%) and reacted for 15 min. After washing five times with ethanol and water, the mixture was vacuum dried at 50 °C. The resulting black powder was the hollow microporous network adsorbent material.

[0049] Hollow molecularly imprinted polymer adsorbent material was obtained through surface molecular imprinting. 1 mmol of 1,4-dihydroxyanthraquinone (DT) was added to a mixture of 25 mL acetonitrile and 5 mL water, and stirred with a magnetic stirrer until completely dissolved. Next, functional monomers (APTES), crosslinking agent (TEOS), and ammonia were added to the system at a molar ratio of 1:4:9. After thorough mixing, 3 mL of HMON dispersed in acetonitrile was added. Subsequently, the entire reaction system was continuously purged with nitrogen for 15 minutes to remove oxygen. Finally, the flask was sealed and stirred overnight at room temperature. The resulting precipitate was washed three times with methanol and water, and then eluted using a Soxhlet extraction apparatus. The eluent consisted of acetone and acetic acid (9:1, v / v). The resulting solid was the hollow molecularly imprinted polymer HMON@MIP.

[0050] The prepared product was characterized, and the results are as follows: Figure 1 As shown, Figure 1 A shows transmission electron microscopy (TEM) and scanning electron microscopy (SEM) images of a series of intermediate materials used in the preparation of HMON@MIP. Figure 1 B represents the dynamic light scattering analysis of the hollow microporous network adsorbent material and the molecularly imprinted polymer, indicating that the prepared hollow adsorbent material has better particle size uniformity, with a size of about 600 nm.

[0051] Example 2: Adsorption and enrichment of pollutants by hollow molecularly imprinted polymers

[0052] The material obtained in Example 1 was placed in a solution of aflatoxin ST to achieve enrichment of aflatoxin ST. Quantitative detection could then be performed using high-performance liquid chromatography.

[0053] To verify the specificity of the hollow molecularly imprinted polymer, equal amounts of the polymer were placed in standard solutions of ochratoxin A, aflatoxin B1, aflatoxin B2, aflatoxin M1, microcystin LR, vomitoxin DON, and zearalenone ZEN, respectively, following the same procedure, to achieve adsorption of these interfering toxins. The results are as follows... Figure 2 As shown, the evaluation of the specificity of the hollow molecularly imprinted polymer adsorbent material indicates that the prepared hollow adsorbent material has good adsorption performance only for ST, which proves the strong specificity of the material.

[0054] Example 3: Repeatability Study of Hollow Molecularly Imprinted Polymers

[0055] The hollow adsorbent material obtained in Example 1 was eluted and sonicated for 20 min until no adsorbed target was detected in the supernatant. The thoroughly washed material was placed in a vacuum oven and dried overnight at 40°C. The dried material underwent the same adsorption-elution-analysis procedure as before, and the average value was calculated in three parallel determinations. The process was repeated 20 times, and the recovery rate of the target analyte was compared each time. The results are as follows: Figure 3 As shown in the figure, the results indicate that the prepared hollow adsorbent material has good reusability and can still achieve a high recovery rate after 20 consecutive uses, making it applicable to actual samples.

[0056] The embodiments of the present invention have been described in detail above, but the content described is only a preferred embodiment of the present invention and should not be considered as limiting the scope of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the patent coverage of the present invention.

Claims

1. The application of hollow molecularly imprinted polymers in the adsorption of food or environmental pollutants, characterized by: The preparation method of hollow molecularly imprinted polymers includes: preparing magnetic composite microporous network adsorbent materials, synthesizing hollow microporous network adsorbent materials through HF etching, and then obtaining hollow molecularly imprinted polymer adsorbent materials through surface molecular imprinting; the specific steps include: Step 1: Prepare magnetic composite microporous organic framework materials using an in-situ growth method; Preparation of magnetic Fe3O4: FeCl3·6H2O, anhydrous sodium acetate, and ethylene glycol were mixed and then heated to 200... o C. Hydrothermal reaction, product washing and drying, yielding magnetic Fe3O4; Preparation of magnetic Fe3O4@SiO2: Take 1.0 g of magnetic Fe3O4, add 200 mL of HCl, sonicate, rinse the product and add 80 mL of ultrapure water, 320 mL of ethanol and 5 mL of ammonia, sonicate again; then add 1 mL of TEOS, stir mechanically, collect the product with a magnet to obtain magnetic Fe3O4@SiO2. Preparation of magnetic Fe3O4@SiO2@UiO-66-NH2: 150 mg of magnetic Fe3O4@SiO2 was taken, 300 mg of zirconium chloride (IV), 75 µL of water, and 30 mL of LDMF were added and stirred. 2-Aminoterephthalic acid was added and stirred to dissolve. The reaction was carried out at 120 °C with hydrothermal reaction. After the reaction was completed, the brown-black magnetic microspheres were collected, washed and dried to obtain magnetic Fe3O4@SiO2@UiO-66-NH2. Preparation of magnetic Fe3O4@SiO2@UiO-66-NH2@MON: Take 200 mg of Fe3O4@SiO2@UiO-66-NH2, add 15 mL of toluene, 15 mL of triethylamine and catalyst, disperse completely, and then heat at 90°C. o Stir mechanically at C for 0.5 h, add 50 mg of tetrakis(4-ethynylphenyl)methane and 80 mg of 1,4-diiodobenzene, and heat at 90 °C. o After heating at C for 6 hours, the product was collected with a magnet after the reaction was completed. The product was washed and dried to obtain the magnetic composite microporous network adsorbent material Fe3O4@SiO2@UiO-66-NH2@MON. Step 2: Synthesize hollow microporous network adsorbent material by HF etching; Take 100.0 mg Fe3O4@SiO2@UiO-66-NH2@MON, add 10 ml HF (5%) and react for 15 min. After washing and drying, obtain hollow microporous network adsorbent material HMON. Step 3: Obtain hollow molecularly imprinted polymer adsorbent material through surface molecular imprinting; add 1 mmol DT to a mixture of 25 mL acetonitrile and 5 mL water and mix well. Add functional monomer (APTES), crosslinking agent (TEOS) and ammonia water to the system in a ratio of 1:4:9; after mixing evenly, add 3 mL HMON dispersed in acetonitrile; remove oxygen from the reaction system, stir overnight at room temperature, wash the obtained product with methanol and water, and then elute with a Soxhlet extractor composed of acetone and acetic acid (9:1, v / v). The precipitate obtained is the hollow molecularly imprinted polymer HMON@MIP; The prepared hollow molecularly imprinted adsorbent material has good particle size uniformity. The hollow structure of the material greatly increases the density of imprinted sites, and the hollow microporous organic material core enhances the hydrophobicity of the material surface and interior. After adsorption, the hollow molecularly imprinted polymer can be eluted with an eluent and reused for the adsorption or enrichment of pollutants.

2. The application according to claim 1, characterized in that: The catalysts used in step one for preparing magnetic Fe3O4@SiO2@UiO-66-NH2@MON were 3.4 mg of bis(triphenylphosphine)palladium(II) chloride and 1.0 mg of cuprous iodide.

3. The application according to claim 1, characterized in that: The drying temperature is 50-60℃.

4. The application according to claim 1, characterized in that: The resulting hollow molecularly imprinted polymer material is placed in the target solution to achieve adsorption or enrichment of pollutants.

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