Graphene oxide / super-hydrophilic molecularly imprinted resin material, preparation method and application thereof

Abstract

The application provides a graphene oxide / super-hydrophilic molecular imprinting resin material, a preparation method and application thereof. The preparation method of the material is as follows: dopamine is used as a functional modification agent, polydopamine is grafted on the surface of graphene oxide to obtain polydopamine functionalized graphene oxide; then the polydopamine functionalized graphene oxide is used as a base, dopamine is used as a functional monomer, caffeic acid is used as a virtual fragment imprinting template, and urotropine is used as a crosslinking agent to synthesize a surface imprinting material in an aqueous phase; and finally, the graphene oxide / super-hydrophilic molecular imprinting resin material is obtained after washing and freeze-drying. The material is synthesized by one-pot method, and the intermediate material does not need to be separated, washed and dried, the synthesis process is simple, the synthesis time is short, and compared with a traditional phenolic resin preparation method, the use of an organic solvent is avoided, an acid-base catalyst is not needed, and raw materials are more low-toxic and green. The material prepared by the application can be used for selective extraction and detection of chlorogenic acid in goldenrod.

Description

Technical Field

[0001] This invention relates to the field of composite material technology, specifically to a graphene oxide / superhydrophilic molecularly imprinted resin material, its preparation method, and its applications. Background Technology

[0002] Molecularly imprinted materials (MIPs) have been widely used for the separation and analysis of target components in complex samples due to their advantages such as high selectivity, strong designability, and high stability. However, with the deepening of applications, some shortcomings have been found in current MIPs: the imprinted sites are easily embedded and have a small specific surface area, resulting in low adsorption capacity. Many MIPs are mainly synthesized in organic solvent systems (N,N-dimethylformamide, acetonitrile, toluene, etc.), exhibiting poor recognition and adsorption performance in aqueous solutions. Therefore, the development of water-compatible surface molecularly imprinted materials is crucial for improving the selective recognition of target analytes in aqueous systems.

[0003] Hydrophilic molecularly imprinted resins (HMIRs) contain a large number of hydrophilic groups, such as hydroxyl and amino groups, thus exhibiting excellent aqueous compatibility and cross-linked network structure. They have been used for the extraction and separation of metal ions, pollutants, proteins, etc. Chinese invention patent (application number 202010167306.1) discloses hydrophilic molecularly imprinted resins, their preparation methods, and applications. It describes the preparation of a dual-template hydrophilic molecularly imprinted resin adsorbent. The resulting dual-template hydrophilic imprinted resin exhibits large adsorption capacity, strong specificity and selectivity, and high extraction efficiency. It not only possesses excellent aqueous phase recognition ability but can also specifically recognize different types of target analytes, making it suitable as an adsorbent material for solid-phase extraction. Chinese invention patent (application number 202110273357.7) discloses a hydrophilic molecularly imprinted nanocomposite resin based on magnetic graphene oxide, its preparation method, and its application. It employs a two-step template fixation method combined with surface imprinting technology, where template molecules are fixed twice on the surface of the imprint matrix. Compared to hydrophilic imprinted materials prepared by a one-step template fixation method, the two-step template fixation strategy produces hydrophilic imprinted materials with higher adsorption capacity and selectivity. It overcomes common problems in imprinted materials such as excessive template embedding, low adsorption capacity, and slow mass transfer rate, while also simplifying analytical procedures, reducing experimental costs, and integrating enrichment and separation. However, this patent uses resorcinol and melamine as amphiphilic monomers and formaldehyde as a hydrophilic crosslinking agent. Since formaldehyde and other substances are highly harmful to human health, exploring green, low-toxicity, and water-compatible monomers and crosslinking agents is a strategy for preparing environmentally friendly HMIRs. Summary of the Invention

[0004] The purpose of this invention is to provide a graphene oxide / superhydrophilic molecularly imprinted resin material, its preparation method and application. This invention is the first to use a novel green biocompatible monomer, dopamine, and a low-toxicity crosslinking agent, hexamethylenetetramine, to replace the traditional resin monomer and crosslinking agent, thereby synthesizing a superhydrophilic surface molecularly imprinted material with graphene oxide as the carrier. The material preparation process is simple, time-saving, and easy to operate.

[0005] This invention is implemented as follows:

[0006] A graphene oxide / superhydrophilic molecular imprinted resin material is prepared in an aqueous system using surface imprinting technology. It employs dopamine as a monomer, hexamethylenetetramine as a crosslinking agent, caffeic acid as a virtual template, graphene oxide as a substrate, and dopamine as a functionalizing agent to covalently modify and connect the graphene oxide and the imprinted resin layer.

[0007] This invention employs a one-pot method to prepare a chemically covalently modified graphene oxide / superhydrophilic molecularly imprinted resin material. Green and low-toxicity reagents are used as monomers and crosslinking agents to modify graphene oxide, which is then used as an adsorbent for sample pretreatment.

[0008] In the material preparation process, this study explores the preparation of hydrophilic surface molecularly imprinted materials using an aqueous system to overcome the shortcomings of traditional molecularly imprinted materials prepared in organic solvents and their poor recognition ability in aqueous phases. Dopamine has a dual function in the preparation process: it not only forms polydopamine as a bridge to covalently connect graphene oxide and the imprinted resin layer, but also serves as a novel green functional monomer for molecular imprinting to improve the adsorption performance of traditional molecularly imprinted polymers.

[0009] This invention utilizes biocompatible dopamine as a monomer and hexamethylenetetramine as a crosslinking agent, without the need for additional catalysts, to perform surface molecular imprinting on graphene oxide sheets. As an adsorbent material, it exhibits fast mass transfer rate, high selectivity, and high adsorption capacity, and can be used to extract and detect chlorogenic acid in Solidago virgaurea.

[0010] The preparation method of the graphene oxide / superhydrophilic molecularly imprinted resin material provided by this invention specifically includes the following steps:

[0011] (1) Graphene oxide was ultrasonically dispersed in Tris-HCl buffer solution to ensure uniform dispersion; dopamine was added and reacted at 15-30℃ for 6-12 hours to obtain polydopamine-functionalized graphene oxide (PGO) suspension.

[0012] (2) Add the monomer dopamine and the cross-linking agent hexamethylenetetramine to the PGO suspension, and then stir at 40°C for 1-2 hours to obtain a black suspension;

[0013] (3) Add the template caffeic acid to the above black suspension and stir it to self-assemble;

[0014] (4) After self-assembly, react in an oil bath at 40-80℃ for 6-18 hours;

[0015] (5) Wash with methanol:acetic acid (9:1) to remove template molecules, then wash with methanol, and finally wash with deionized water until pH 7, and freeze dry to obtain graphene oxide / superhydrophilic molecular imprinted resin material SMIR / PGO.

[0016] Preferably, in step (1), the ultrasonic time is 2 to 3 hours, the ultrasonic frequency is 40 to 100 kHz, and the ultrasonic power is 100 to 700 W.

[0017] Preferably, in step (1), the mass ratio of graphene oxide to dopamine is 1:(1-4).

[0018] Preferably, the Tris-HCl buffer solution in step (1) can be replaced with other weakly alkaline aqueous solutions.

[0019] In step (1), PGO is prepared by a one-pot method, without the need for washing, separation, and drying steps, and can be directly carried out in the next reaction.

[0020] Preferably, the molar ratio of the template in step (3) to the monomer and crosslinking agent in step (2) is 1:(3-40):(1-40).

[0021] In step (3), the virtual fragment imprinting technique is used, and a portion of the chlorogenic acid structure, namely caffeic acid, is selected as the virtual template.

[0022] The graphene oxide / superhydrophilic molecularly imprinted resin material prepared in this invention is used as an adsorbent for the extraction and detection of chlorogenic acid.

[0023] This invention provides a method for preparing a superhydrophilic surface molecularly imprinted resin material based on graphene oxide. First, dopamine is used as a functionalizing agent to modify graphene oxide. Second, dopamine is used as a biocompatible monomer, caffeic acid as a virtual template, and hexamethylenetetramine as a crosslinking agent to synthesize the surface molecularly imprinted resin material in an aqueous phase in a one-pot process, avoiding the use of organic solvents. In this invention, dopamine plays a dual role in both modifying the graphene oxide surface and acting as an imprinting functional monomer, thus achieving a simple one-pot preparation of the superhydrophilic surface molecularly imprinted resin material. After obtaining the polydopamine-modified graphene oxide, there is no need for cumbersome steps of separating, washing, and drying intermediate materials (PGO); the next reaction can proceed directly. Compared with the preparation of conventional surface molecularly imprinted materials, this method has the advantages of simplicity, short time, and fewer steps. Furthermore, when the obtained material is used as an adsorbent for the extraction and detection of chlorogenic acid, interference caused by template leakage can be effectively avoided. Since caffeic acid and the analyte chlorogenic acid have highly similar functional group and shape characteristics, it is beneficial to obtain an imprinted material with high selectivity for chlorogenic acid.

[0024] In this invention, graphene oxide and superhydrophilic molecularly imprinted resin are covalently linked. The superhydrophilic molecularly imprinted resin avoids the problem of easy stacking of graphene oxide sheets, maintaining a large specific surface area. The superhydrophilic molecularly imprinted resin grafted onto the surface of graphene oxide results in a material rich in functional groups, providing various adsorption forces and improving adsorption capacity and selectivity. The graphene oxide / superhydrophilic molecularly imprinted resin material prepared in this invention exhibits a loose, porous structure, high adsorption capacity, and good selectivity, making it suitable as an adsorbent material for sample pretreatment. Attached Figure Description

[0025] Figure 1 The images show scanning electron microscope (SEM) images of the graphene oxide material in Example 1 at 10,000x magnification and the graphene oxide / superhydrophilic molecularly imprinted resin material at 10,000x magnification.

[0026] Figure 2 The graphene oxide material in Example 1 and the prepared graphene oxide / superhydrophilic molecularly imprinted resin material were used in the range of 500–4000 cm⁻¹. -1 Infrared spectrum within the wavenumber range.

[0027] Figure 3 The images show the X-ray photoelectron spectra of the graphene oxide material in Example 1 and the prepared graphene oxide / superhydrophilic molecularly imprinted resin material.

[0028] Figure 4 The diagram shows the organic elemental analysis of the graphene oxide material in Example 1 and the prepared graphene oxide / superhydrophilic molecularly imprinted resin material.

[0029] Figure 5 This is a characterization diagram of the hydrophilicity of the graphene oxide / superhydrophilic molecularly imprinted resin material prepared in Example 1.

[0030] Figure 6 This is a comparison chart of the adsorption capacity of chlorogenic acid by the graphene oxide / superhydrophilic molecular imprinted resin material and the graphene oxide / superhydrophilic molecular non-imprinted resin material in Example 3.

[0031] Figure 7 This is a comparison chart of the adsorption capacity of chlorogenic acid by the graphene oxide / superhydrophilic molecularly imprinted resin material and the commercial adsorbent in Example 4.

[0032] Figure 8 This is a comparison chart of the adsorption capacity of chlorogenic acid by the graphene oxide / superhydrophilic molecular imprinted resin material synthesized with different solvents and the graphene oxide / superhydrophilic molecular non-imprinted resin material in Example 5.

[0033] Figure 9 This is a graph showing the adsorption amounts of compounds with different structures by the graphene oxide / superhydrophilic molecularly imprinted resin in Example 6. Detailed Implementation

[0034] The present invention will be further described below with reference to the accompanying drawings. The specific embodiments described are only used to explain the present invention and are not intended to limit the present invention.

[0035] In the following embodiments, the processes and methods not described in detail are all conventional methods known in the art, and the reagents used are all commercially available analytical grade or chemically pure. The following embodiments all achieve the inventive objectives of this invention.

[0036] Example 1

[0037] 50 mg of graphene oxide was weighed and ultrasonically dispersed in 100 mL of 20 mM Tris-HCl buffer solution (pH 8.5) at a power of 150 W, a frequency of 45 kHz, and a duration of 3 h to obtain a graphene oxide dispersion. Then, dopamine (1.0 mmol) was added to the graphene oxide dispersion, and the mixture was stirred at 25 °C for 12 h to obtain a polydopamine-modified graphene oxide (PGO) dispersion. Subsequently, dopamine (4 mmol) and hexamethylenetetramine (4 mmol) were added to the PGO dispersion, and the mixture was stirred at 40 °C for 1 h to obtain a black suspension. Then, 18.02 mg of template caffeic acid was added to the above black suspension, allowing it to self-assemble for 1 h, and then reacted in an oil bath at 80 °C for 18 h. The template molecules in the material were washed away with methanol:acetic acid (9:1, v / v), followed by washing with methanol, and finally washing with deionized water until the pH reached 7. The material was then freeze-dried to obtain graphene oxide / superhydrophilic molecularly imprinted resin material (SMIR / PGO).

[0038] Scanning electron microscopy (SEM) tests were performed on graphene oxide and the graphene oxide / superhydrophilic molecularly imprinted resin material obtained in this embodiment. The results are as follows: Figure 1 As shown. By Figure 1 It is known that graphene oxide exhibits a folded layered structure similar to silk. As polydopamine and imprinted resin layers grow on the surface of graphene oxide, the resulting SMIR / PGO exhibits a porous, fluffy, cross-linked network structure.

[0039] Infrared spectroscopy was performed on graphene oxide and the graphene oxide / superhydrophilic molecularly imprinted resin material obtained in this embodiment. The results are as follows: Figure 2 As shown. Figure 2 3390, 1714 and 1058cm –1 The peaks at 1197 and 1510 cm⁻¹ are attributed to the OH, C=O, and COC groups of graphene oxide, respectively. However, the C=O absorption peak disappeared in the SMIR / PGO infrared spectrum, which may be due to the reduction of oxygen-containing functional groups in graphene oxide during polydopamine modification and molecular imprinting. Furthermore, peaks appearing at 1197 and 1510 cm⁻¹... –1 The peaks at the positions are attributed to CN and NH, respectively, indicating that SMIR (superhydrophilic molecularly imprinted resin) has been grafted onto the surface of graphene oxide.

[0040] X-ray photoelectron spectroscopy was used to characterize graphene oxide and the SMIR / PGO obtained in this example. The results are as follows: Figure 3 As shown. In Figure 3 In the graph, peaks O1s and C1s belong to graphene oxide, while N1s originates from the imprinted resin layer. The XPS method can be used to determine whether the imprinted resin has been successfully modified onto graphene oxide.

[0041] Figure 4 The results of elemental analysis show that the SMIR / PGO obtained in this embodiment contains 6% N, which comes from the monomer dopamine, indicating that the imprinted resin was successfully modified with graphene oxide.

[0042] Figure 5 The contact angle test results of SMIR / PGO in this embodiment show that a water droplet can completely penetrate the material in just 0.066s, indicating that the obtained SMIR / PGO has super hydrophilic properties.

[0043] Example 2

[0044] Graphene oxide (0.05 g) was dispersed in 100 mL of 20 mM Tris-HCl buffer solution (pH 8.5), and sonicated at 100 W and 100 kHz for 2 h to obtain a graphene oxide dispersion. Dopamine (1.0 mmol) was then introduced into the graphene oxide dispersion, and the mixture was stirred at 25 °C for 12 h to obtain polydopamine-modified graphene oxide (PGO). Subsequently, dopamine (4 mmol) and hexamethylenetetramine (2 mmol) were added to the PGO suspension, and the mixture was stirred at 40 °C for 1 h to obtain a black suspension. Then, 36.04 mg of template caffeic acid was added to the black suspension, allowing it to self-assemble for 1 h, followed by reaction in an oil bath at 80 °C for 12 h. The mixture was washed sequentially with methanol:acetic acid (9:1, v / v), methanol, and water, and then freeze-dried under vacuum to obtain SMIR / PGO.

[0045] Example 3

[0046] The graphene oxide / superhydrophilic molecularly imprinted resin material prepared in Example 1 of this invention was used as an adsorbent to investigate its adsorption kinetics for chlorogenic acid, and it was compared with non-imprinted materials.

[0047] Preparation of non-imprinted materials: The same preparation method as the graphene oxide / superhydrophilic molecular imprinted resin material (SMIR / PGO) in Example 1 was used, but without adding template caffeic acid, to prepare graphene oxide / superhydrophilic molecular non-imprinted resin material (SNIR / PGO).

[0048] SNIR / PGO (2.0 mg) and SMIR / PGO (2.0 mg) were added to chlorogenic acid standard solution (50 μg / mL) respectively. –1 The solution was added to a container (2.0 mL). The container was shaken on a shaker at 25°C for different times (1, 5, 10, 30, 60, 120, 240 min). After centrifugation, the supernatant was collected for liquid chromatography analysis using a UV detector (detection wavelength 290 nm). The results are shown below. Figure 6 As shown. By Figure 6 It can be seen that for SMIR / PGO, the adsorption capacity increases significantly in the first 10 minutes, which is attributed to the abundant imprinted sites on the imprinted layer. Subsequently, the adsorption capacity increases slowly and reaches adsorption equilibrium within 30 minutes. In contrast, for SNIR / PGO, it takes a longer adsorption time (60 minutes) to reach adsorption equilibrium. This may be because the selective imprinted recognition sites of surface molecularly imprinted materials are mostly located on the material surface. Therefore, SMIR / PGO reaches adsorption equilibrium faster than SNIR / PGO, indicating that SMIR / PGO has a faster mass transfer rate.

[0049] Example 4

[0050] The graphene oxide / superhydrophilic molecularly imprinted resin material prepared in Example 1 of this invention was used as an adsorbent to investigate its differences from other commercial adsorbent materials and non-imprinted materials (the non-imprinted materials were obtained by the method described in Example 3).

[0051] Weigh 2 mg of each material (C18, silica gel, SAX, graphene, SNIR / PGO, and SMIR / PGO) into a 10 mL centrifuge tube, and measure 2 mL of each material with a concentration of 50 μg / mL. –1 The chlorogenic acid standard solution was prepared. The mixture was shaken on a shaker at 25°C for 12 hours, centrifuged, and the supernatant was then subjected to high-performance liquid chromatography (HPLC) analysis using a UV detector (detection wavelength 290 nm). The results are shown below. Figure 7 As shown. Figure 7 The adsorption capacity of SMIR / PGO for chlorogenic acid was shown to be 40.2 mg / g. –1 Higher than commercial adsorbents (0.54–7.17 mg g) –1 The study compared SMIR / PGO with non-imprinted materials. SMIR / PGO possesses multiple adsorption interactions (electrostatic adsorption, π-π conjugation, and hydrogen bonding) and selectively imprinted cavities, enabling the synergistic adsorption of the target compound chlorogenic acid. Results showed that SMIR / PGO significantly outperformed commercial adsorbents in recognizing chlorogenic acid in aqueous systems.

[0052] Example 5

[0053] The graphene oxide / superhydrophilic molecularly imprinted resin material prepared in Example 1 of this invention was used as an adsorbent to investigate its differences from materials synthesized with different solvents and non-imprinted materials (the non-imprinted materials were obtained by the method described in Example 3).

[0054] Preparation of materials synthesized by acetonitrile solvent: The same preparation method as that used for the graphene oxide / superhydrophilic molecularly imprinted resin material (SMIR / PGO) in Example 1 was adopted, except that the reaction solvent Tris-HCl buffer solution was replaced with acetonitrile (ACN) to obtain the graphene oxide / superhydrophilic molecularly imprinted resin material (SMIR / PGO-ACN).

[0055] Preparation of DMF solvent-based materials: The same preparation method as that used for the graphene oxide / superhydrophilic molecularly imprinted resin material (SMIR / PGO) in Example 1 was adopted, except that the reaction solvent Tris-HCl buffer solution was replaced with N,N-dimethylformamide (DMF) to obtain the graphene oxide / superhydrophilic molecularly imprinted resin material (SMIR / PGO-DMF).

[0056] Weigh 2 mg of each material (SMIR / PGO, SNIR / PGO, SMIR / PGO-ACN, SMIR / PGO-DMF) into a 10 mL centrifuge tube, and measure 2 mL of each material with a concentration of 500 μg / mL. –1 The chlorogenic acid standard solution was prepared. The mixture was shaken on a shaker at 25°C for 12 hours, centrifuged, and the supernatant was then subjected to high-performance liquid chromatography (HPLC) analysis using a UV detector (detection wavelength 290 nm). The results are shown below. Figure 8 As shown. Figure 8 The results showed that the SMIR / PGO synthesized in the aqueous phase adsorbed chlorogenic acid (97.6 mg g). –1 The concentration was significantly higher than that in acetonitrile (7.2 mg g). –1 ) and DMF (10.6 mg g) –1 The material was synthesized in an aqueous system. By comparing SMIR / PGO with the non-imprinted material SNIR / PGO, it was found that the imprinting factor (IF) of SMIR / PGO was 3.5, indicating that this preparation strategy can achieve excellent imprinting effects in aqueous solution. Therefore, choosing to prepare SMIR / PGO in an aqueous system not only avoids the waste and pollution of organic solvents, but also provides better adsorption performance than that synthesized in organic solvents, thus providing a green synthesis method for water-compatible molecularly imprinted materials.

[0057] Example 6

[0058] Using the graphene oxide / superhydrophilic molecularly imprinted resin material prepared in Example 1 of this invention as an adsorbent, compounds with different structures were used to further investigate its adsorption selectivity.

[0059] SMIR / PGO (2.0 mg) was added to 40 μg mL –1 The mixture was added to 2.0 mL of a standard solution (chlorogenic acid, rutin, protocopherol, and atrazine) and then shaken at 25 °C for 12 h. The mixture was then centrifuged at 4000 rpm for 5.0 min, and the supernatant was analyzed by liquid chromatography using a UV detector (detection wavelength 290 nm) to determine the adsorption capacity of different analytes. The results are shown below. Figure 9 As shown. Chlorogenic acid is the target analyte in this invention, possessing a catechol and carboxyl structure similar to the template caffeic acid; rutin is a polyphenol compound with a catechol structure; protocopherol is an alkaloid compound; and atrazine is another type of compound with a significantly different chemical structure from the template. Figure 9 It is known that the graphene oxide / superhydrophilic molecularly imprinted resin material prepared in this invention has high adsorption selectivity for chlorogenic acid.

[0060] Example 7

[0061] The graphene oxide / superhydrophilic molecularly imprinted resin material prepared in Example 1 of this invention was used as an adsorbent, and centrifugal accelerated tube tip solid-phase extraction-liquid chromatography was used for the extraction and detection of chlorogenic acid in actual samples of Solidago virgaurea.

[0062] Goldenrod sample was pulverized into powder and passed through a 300-mesh sieve. 40 mg of the sample powder was dispersed in 40 mL of methanol:water (7:3, v / v) in a 50 mL centrifuge tube, and extracted by sonication for 1 h, followed by centrifugation at 4000 rpm for 5 min. The supernatant was then removed by rotary evaporation, and the residue was redissolved in 40.0 mL of water (pH 3). 10.0 mg of graphene oxide / superhydrophilic molecularly imprinted resin material was added to a self-assembled solid-phase extraction column, which was then activated with 1.0 mL of methanol and water, respectively. Subsequently, 1.0 mL of the goldenrod sample solution was added to the extraction column, washed with 1.0 mL of water, and eluted with 1.2 mL of methanol:formic acid (9:1, v / v). The eluent was evaporated to dryness with N2, redissolved in 1.0 mL of mobile phase, and then analyzed by liquid chromatography. The results showed that the chlorogenic acid content in goldenrod from Henan and Guizhou was 6.87 μg mg. –1 and 5.34 μg mg –1 This indicates that the graphene oxide / superhydrophilic molecularly imprinted resin material prepared in this invention has good adsorption properties for the target analyte chlorogenic acid, and can be used for the extraction and detection of chlorogenic acid in complex samples.

[0063] The graphene oxide / superhydrophilic molecularly imprinted resin material prepared in Example 2 of this invention has the same properties as the material obtained in Example 1.

Claims

1. An application of a graphene oxide / superhydrophilic molecularly imprinted resin material, characterized in that, The graphene oxide / superhydrophilic molecularly imprinted resin material is used as an adsorbent for the extraction and detection of chlorogenic acid. The preparation method of the graphene oxide / superhydrophilic molecularly imprinted resin material includes the following steps: (1) Graphene oxide was ultrasonically dispersed in Tris-HCl buffer solution to ensure uniform dispersion; then dopamine was added and reacted at 15~30 ℃ for 6~12 h to obtain polydopamine-functionalized graphene oxide suspension. (2) Add the monomer dopamine and the crosslinking agent hexamethylene to the polydopamine-functionalized graphene oxide suspension obtained in step (1), and then stir at 40 °C for 1-2 h to obtain a black suspension; (3) Add the virtual fragment imprint template caffeic acid to the above black suspension to allow it to self-assemble; (4) After self-assembly, react in an oil bath at 40~80 ℃ for 6~18 h; (5) The template molecules were removed by washing with a mixture of methanol and acetic acid in a volume ratio of 9:1, then washed with methanol, and finally washed with deionized water until the pH was 7. The material was then freeze-dried to obtain graphene oxide / superhydrophilic molecular imprinted resin material.

2. The application of the graphene oxide / superhydrophilic molecularly imprinted resin material according to claim 1, characterized in that, In step (1), the ultrasound time is 2-3 hours, the ultrasound frequency is 40-100 kHz, and the ultrasound power is 100-700 W.

3. The application of the graphene oxide / superhydrophilic molecularly imprinted resin material according to claim 1, characterized in that, In step (1), the mass ratio of graphene oxide to dopamine is 1:(1~4).

4. The application of the graphene oxide / superhydrophilic molecularly imprinted resin material according to claim 1, characterized in that, In step (3), the molar ratio of the template to the monomer and crosslinking agent in step (2) is 1:(3~40):(1~40).

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