Preparation method and application of high-activity multi-level pore boric acid imprinting hydrogel microsphere adsorbent

Abstract

The application discloses a preparation method of a high-activity multi-level-pore boronic acid imprinting hydrogel microsphere adsorbent and application of the adsorbent to selective adsorption of a flavonoid compound naringin (NRG). The application enhances surface functionalization of COFs by dopamine modification, prepares thiol functionalized covalent organic framework microspheres, synthesizes thiol microspheres by using an emulsion interfacial polymerization method, prepares COFs boron affinity imprinting microsphere adsorbents based on boron affinity, and applies the adsorbents to selective adsorption of NRG in agricultural wastewater. The prepared adsorbent has a significant multi-layer adsorption effect, and the adsorption capacity is significantly improved by using boron affinity. The multi-level-pore structure of the COFs microspheres provides abundant sites for adsorption, and significantly improves the mass transfer rate. In addition, the prepared adsorbent has significant specificity in adsorption and separation of NRG, and provides a promising adsorption material for industrialized separation of NRG.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of environmental materials, and relates to a preparation method of a multi-level porous borate affinity imprinting hydrogel microsphere adsorbent based on an emulsion template method through emulsion interfacial cross-linking interaction and application in the purification of agricultural environmental waste naringin. BACKGROUND

[0002] Naringin is a bioactive compound that exists in large quantities in by-products of citrus fruit processing. The content of naringin in different parts of grapefruit varies greatly, with the content of naringin in grapefruit peel accounting for about 70% of the total naringin content in the whole fruit. Naringin has excellent biomedical and industrial properties, such as antioxidant, anticancer, anti-inflammatory, improvement and relief of diabetes and its complications, reduction of blood levels, etc. However, how to effectively extract naringin from agricultural environmental waste is a major research focus. Traditional extraction techniques such as adsorption, Soxhlet extraction, immersion and reflux are usually high in energy consumption or require large amounts of organic solvents and long time, are not reusable, high in cost, time-consuming, poor in selectivity and have negative impact on the environment. The molecular structure of naringin promotes the development of borate affinity, which forms a specific reversible covalent bond with the cis-dihydroxy structure of naringin (NRG). This innovative method opens up new possibilities for the preparation of boron affinity adsorbents to separate NRG. Molecularly imprinted polymers (MIPs) have gained great attention in the field of separation technology. This is largely due to their inherent ability to precisely recognize target molecules, as well as their excellent stability, wide range of applications and universal appeal. Therefore, the combination of boron affinity and molecularly imprinted polymers takes advantage of accessible specific surface-oriented recognition sites and fast mass transfer kinetics. Using borate affinity imprinting recognition sites, high specificity and selectivity for the target (NRG) are achieved. In addition, fast mass transfer kinetics enables boron affinity imprinting polymers to capture efficiently and quickly, which is very suitable for NRG selective separation applications. The developed affinity materials include cellulose nanocrystals, SiO2, carbon nanotubes, metal-organic frameworks, etc. However, the above-mentioned materials have defects such as small specific surface area, slow mass transfer rate, inaccessible contact sites, etc., resulting in low adsorption performance.

[0003] Covalent organic frameworks (COFs) as an important member of the family of porous materials, are formed by covalent bonds of molecular building units, and have received more and more attention in recent years. COFs are widely used in specific adsorption due to their good stability, large specific surface area, easy functionalization and permanent porosity. Microspheres (MCs) are a class of nanomaterials with hollow spherical structure, which have significant structural stability, biocompatibility, selective permeability, etc. and have wide applications in drug delivery, molecular screening, separation technology. Therefore, by modifying the COF functional groups, COFs are combined with microspheres to prepare boron affinity imprinting adsorbents.

[0004] Pickering emulsions are emulsions stabilized by solid particles rather than surfactants. Compared with traditional emulsions, Pickering emulsions have their unique advantages. For example, compared with surfactants, solid particles have higher adsorption energy and the ability to stabilize emulsions, so less amount is required. Based on this point, Pickering emulsions have been widely used in the adsorption field. Pickering particles are tightly fixed between the oil and water interface, which can inhibit the aggregation of particles, provide the maximum specific surface area of catalysts, and improve the adsorption efficiency. SUMMARY

[0005] The present application proposes a preparation method of a separation material with extremely high specific adsorption capacity for NRG in view of a series of defects existing in the existing separation and extraction technology. The technical brief description is as follows: first, functionalizable thiol COFs microspheres (BTCA-COF@-MC) are prepared through an emulsion interface assembly strategy, then an ATRP initiator with a double bond is modified on the surface thereof through a simple hot solvent method to provide accessible active sites for subsequent ATRP imprinting. Finally, boronic acid is used as a functional monomer, NRG is used as a template molecule, and an imprinting cavity with NRG specificity is prepared through pre-assembly, and COFs borate affinity imprinting microspheres are prepared through ATRP.

[0006] The preparation method of the high-activity multi-level pore boronic acid imprinting hydrogel microsphere adsorbent comprises the following steps:

[0007] (1) 1,3,5-tris(4-aminophenyl)benzene and 1,3,5-triformaldehyde benzene are dissolved in a three-necked flask containing acetonitrile, then a chiral phosphonate-based benzaldehyde aniline is added and dispersed in an ultrasonic water bath; then, under the protection of nitrogen, Sc(OTfs)3-containing acetonitrile is continuously added, and first mechanical stirring is performed; then, the obtained product BTCA-COFs is washed with acetonitrile, and vacuum drying is performed;

[0008] Dopamine hydrochloride is dissolved in Tris-HCl buffer solution, and the pH is adjusted with sodium hydroxide solution; then, the BTCA-COFs are added to the solution, and second stirring is performed; then, the obtained product is washed with methanol for several times, centrifuged, dried, and named as BTCA-COF@PDA.

[0009] (2) BTCA-COF@PDA is dispersed in ultrapure water, then 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride and N-hydroxysuccinimide are added, stirred, then mercaptoacetic acid is added, and the mixture is stirred; finally, the obtained sample is washed with ultrapure water, vacuum dried, and the final product is named as BTCA-COF@PDA-SH.

[0010] (3) The BTCA-COF@PDA-SH was uniformly dispersed in mesitylene, and then Sc(OTf)3 was added dropwise. The mixture was subjected to high-speed shearing to obtain a stable oil-in-water (O / W) type Pickering emulsion.

[0011] (4) The Pickering emulsion was transferred to a centrifuge tube, and mesitylene was added. Subsequently, 1,3,5-tris(4-aminophenyl)benzene, 1,3,5-triformylbenzene were dissolved in chloroform, and a competitor benzaldehyde and aniline were added to prepare an emulsion dispersion. The mixture was placed in a centrifuge tube and left to stand at room temperature. The obtained microspheres were named as MC BTCA-COF@PDA-SH.

[0012] (5) The functional monomer 3-acrylamidophenylboronic acid, the template molecule NRG and methanol were added to a flask, and mixed and stirred for pre-assembly. Then, polydi-pentaerythritol five acrylate and benzoin dimethyl ether were added, and ultrasonic treatment was performed. Subsequently, the prepared MC BTCA-COF@PDA-SH was added to the mixed solvent, and nitrogen treatment was performed to prevent oxidation. The molecularly imprinted polymerization was initiated by ultraviolet light. After the reaction was completed, the template molecule NRG was removed by washing with methanol and acetic acid solution, and then washed with ethanol and deionized water several times, respectively. Finally, the product was dried in an oven to obtain a high-activity multi-level pore boronic acid imprinted hydrogel microsphere adsorbent, which was abbreviated as MC@PDA-SH@BA-MIPs.

[0013] In step (1), the amount ratio of 1,3,5-tris(4-aminophenyl)benzene, 1,3,5-triformylbenzene, acetonitrile, chiral phosphonate benzaldehyde, aniline and Sc(OTfs)3 was 17.6 mg:8.1 mg:39 mL:60.8 μL:54.4 μL:11.8 mg; the ultrasonic water bath dispersion time was 30 minutes; the first mechanical stirring temperature was 25℃, and the time was 24 h; the vacuum drying temperature was 60℃, and the drying time was 24 h.

[0014] In step (1), the amount ratio of BTCA-COFs and dopamine hydrochloride was 100 mg:75 mg; the concentration of Tris-HCl buffer was 10 mmol / L; the pH was adjusted to 8.5 by sodium hydroxide solution; the second stirring temperature was 25℃, and the time was 6 h.

[0015] In step (2), the amount ratio of BTCA-COF@PDA, 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride, N-hydroxysuccinimide and mercaptoacetic acid was 20 mg:10 mL:10 mL:52 μL.

[0016] In step (2), after the addition of mercaptoacetic acid, the mixture was stirred at 25℃ for 12 h.

[0017] In step (3), the amount ratio of BTCA-COF@PDA-SH, mesitylene and Sc(OTf)3 is 1.7 mg:4.0 mL:0.2 mL.

[0018] In step (3), the speed of high-speed shearing is 15000 rpm, and the shearing time is 3 min.

[0019] In step (4), the amount ratio of Pickering emulsion, mesitylene, 1,3,5-tris(4-aminophenyl)benzene, 1,3,5-triformylbenzene, chloroform, benzaldehyde and aniline is 2.0 mL:4.0 mL:3.5 mg:1.6 mg:2.0 mL:12.1 μL:10.8 μL; and the standing time at room temperature is 24 h.

[0020] In step (5), the amount ratio of 3-acrylamidophenylboronic acid, NRG, methanol, polydi-pentaerythritol five acrylate, benzoin dimethyl ether and MC BTCA-COF@PDA-SH is 38 mg:29 mg:20.0 mL:58 mg:20 mg:80 mg.

[0021] In step (5), the pre-assembly time is 3.0 h, the ultrasonic treatment time is 10 min; the nitrogen treatment time is 30 min; the molecular imprinting polymerization is initiated by 365 nm ultraviolet light for 60 min; and the volume ratio of methanol to acetic acid in the methanol and acetic acid solution is 9:1.

[0022] Further, the drying temperature is 40-60℃, and the time is not less than 12 h.

[0023] As a control, non-imprinted picospheres (MC@PDA-SH@BA-NIPs) are prepared by the same method, but without adding NRG.

[0024] The high-activity multi-level porous boronic acid imprinted hydrogel microsphere adsorbent MC@PDA-SH@BA-MIPs prepared by the application is used for adsorbing and separating flavonoid compound naringin NRG.

[0025] The above technical solution is only one of the most optimal feasible technical solutions of the application, and the protection scope of the application is not limited to this. The person skilled in the art can reasonably adjust the technical design according to the actual needs.

[0026] The adsorption principle of the application is as follows:

[0027] The adsorbent of the present application can selectively capture NRG from a waste solution of a plurality of cis-dihydroxy interfering substances, that is, NRG selectively forms an NRG-boric acid five-membered ring or six-membered ester ring with the adsorbent, and other interfering substances remain in the original solution. This is because NRG can specifically bind to the specific imprinted cavity formed by the adsorbent, and due to covalent / non-covalent interaction, it can selectively adsorb NRG in agricultural wastewater, while other interfering substances are left in the waste solution because they cannot enter the imprinted cavity, thereby achieving the purpose of improving selective adsorption.

[0028] The present application has the following beneficial effects:

[0029] (1) The present application is based on the preparation of COFs boric affinity imprinted microspheres by emulsion interfacial polymerization, which has abundant multilayer boric affinity imprinting sites on the adsorbent, and shows obvious interface structure of particle adsorption.

[0030] (2) The adsorbent of the present application is a spherical adsorbent, which has the characteristics of good stability, low solution loss rate, high adsorption capacity, and many mass transfer sites.

[0031] (3) The adsorbent prepared by the present application uses commercial raw materials, and the process is simple and has wide adaptability, which is suitable for industrial production. BRIEF DESCRIPTION OF DRAWINGS

[0032] In order to more clearly illustrate the technical path of the present application, the following will introduce the used drawings in the examples (example 1, example 2, example 1), the drawings in the following description are used as examples of the present application, and for those skilled in the art, the drawings can be obtained according to their needs without creative labor. Among them:

[0033] Figure 1 TEM images (a1, a2) of BTCA-COF@PDA-SH in Example 1;

[0034] Figure 2 Scanning images (b1, b2) of MC@PDA-SH@BA-MIPs (a1, a2) and MC@PDA-SH@BA-NIPs prepared in Example 1;

[0035] Figure 3 Energy spectrum analysis diagram of MC@PDA-SH@BA-MIPs adsorbent prepared in Example 1;

[0036] Figure 4 Infrared spectrum of MC@PDA-SH@BA-MIPs and MC@PDA-SH@BA-NIPs prepared in Example 1

[0037] Figure 5Adsorption kinetics fitting curve of MC@PDA-SH@BA-MIPs(a) and MC@PDA-SH@BA-NIPs(b) prepared in Example 1;

[0038] Figure 6 Adsorption isotherm curve of boron affinity microsphere molecular imprinting adsorbent (MC@PDA-SH@BA-MIPs) in Example 2;

[0039] Figure 7 Competitive adsorption column chart of boron affinity microsphere molecular imprinting adsorbent (MC@PDA-SH@BA-MIPs and MC@PDA-SH@BA-NIPs) in Example 3. DETAILED DESCRIPTION

[0040] In order to make the research purposes, characteristics and results of the present application more obvious and easy to understand, the examples of the present application are further illustrated in detail in combination with the specification of the patent.

[0041] Example 1

[0042] (1) Preparation of BTCA-COF@PDA particles:

[0043] 1,3,5-tris(4-aminophenyl)benzene (17.6 mg) and 1,3,5-triformaldehyde benzene (8.1 mg) were dissolved in a three-necked flask containing 39 mL of acetonitrile, and then chiral phosphonate benzaldehyde (60.8 μL) and aniline (54.4 μL) were added and dispersed in an ultrasonic water bath for 30 minutes. Subsequently, Sc(OTfs)3-containing acetonitrile was added to the above solution under nitrogen protection, and mechanically stirred at 25°C for 24 h. Subsequently, the obtained product (BTCA-COFs) was washed with acetonitrile and dried in a vacuum drying oven at 60°C for 24 h. 75 mg of dopamine was dissolved in 50 mL of Tris-HCl buffer solution (concentration of 10 mmol / L), and the pH was adjusted to 8.5 with sodium hydroxide solution. Then, 100 mg of BTCA-COFs was added to the solution and stirred at 25°C for 6 h. Subsequently, the obtained product was washed with methanol three times and centrifuged at 10000 rpm. The product was dried in an oven and named as BTCA-COF@PDA.

[0044] (2) Preparation of thiol-functionalized BTCA-COF@PDA-SH particles: 20 mg of BTCA-COF@PDA was dispersed in 30 mL of ultrapure water, and then 10 mL of 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride and 10 mL of N-hydroxysuccinimide (6.0 mg / L) were added. After stirring for 2 h, 52 μL of mercaptoacetic acid was added to the above reaction system. The mixture was stirred at 25 °C for 12 h. Finally, the obtained sample was washed with ultrapure water and dried in a vacuum drying oven, and the final product was named as BTCA-COF@PDA-SH.

[0045] (3) Preparation of Pickering emulsion: First, 1.7 mg of BTCA-COF@PDA-SH was uniformly dispersed in 4.0 mL of trimethylbenzene. Then, 0.2 mL of Sc(OTf)3 was added dropwise to the mixture. The mixture was sheared at high speed to obtain a stable oil-in-water (O / W) type Pickering emulsion.

[0046] (4) Preparation of COFs picosphere by emulsion interfacial polymerization:

[0047] 2 mL of Pickering emulsion was transferred to a centrifuge tube, and 4 mL of trimethylbenzene was added. Subsequently, 3.5 mg of 1,3,5-tris(4-aminophenyl)benzene, 1.6 mg of 1,3,5-triformaldehyde benzene was dissolved in 2 mL of chloroform, and a competitor (12.1 μL of benzaldehyde and 10.8 μL of aniline) was added to prepare an emulsion dispersion. The mixture was placed in a 10 mL centrifuge tube and left to stand at room temperature for 24 h. The obtained picosphere was named as MCBTCA-COF@PDA-SH.

[0048] (5) Preparation of COFs boron affinity imprinted picospheres: Functional monomer (3-acrylamidophenylboronic acid, 38 mg), template molecule (NRG, 29 mg), and methanol (20.0 mL) were added to a 50 mL flask, and mixed and stirred for 3.0 h for pre-assembly. Then, 58 mg of polydiisopentaerythritol pentaacrylate and 20 mg of benzoin dimethyl ether were added, and ultrasonic treatment was performed for 10 min. Subsequently, the prepared MCBTCA-COF@PDA-SH was added to the mixed solvent, and nitrogen treatment was performed for 30 min to prevent oxidation. Molecular imprinting polymerization was initiated by 365 nm ultraviolet light for 60 min. The prepared MCBTCA-COF@PDA-SH@BA-MIPs imprinted picospheres were washed with a methanol / acetic acid (9:1, v / v) solution to remove the template molecule NRG, and then washed with ethanol and deionized water several times, respectively. The final product was dried in an oven. As a control, non-imprinted picospheres (MCBTCA-COF@PDA-SH@BA-NIPs) were prepared by the same method, but without the addition of NRG.

[0049] As Figure 1As shown in the transmission image of BTCA-COF@PDA-SH, the size of COFs monomers is about 120 nm, which is uniform and rough, which can be attributed to the growth of dopamine on the outer layer of COFs. As can be seen in Figure a2, BTCA-COF@PDA-SH shows uniform pores.

[0050] As shown in Figure Figure 2 , MC@PDA-SH@BA-MIPs and MC@PDA-SH@BA-NIPs exhibit uniform spherical morphology. Through layer-by-layer modification, the surface of the picosphere becomes rough and has many COFs particles. Imprinted picospheres and non-imprinted picospheres show similar morphology, indicating that MC@PDA-SH@BA-MIPs are successfully synthesized.

[0051] As shown in Figure Figure 3 , from the energy spectrum analysis diagram, it can be seen that C, N, O and B elements show obvious peaks in the binding energy. It is shown that COFs boron affinity imprinted polymer microspheres MC@PDA-SH@BA-MIPs are successfully prepared by ultraviolet-photopolymerization.

[0052] As shown in Figure Figure 4 , from the infrared spectrum diagram, it can be seen that there are obvious peaks at 1389 cm -1 showing the stretching peak of B-O, indicating that MC@PDA-SH@BA-MIPs are successfully synthesized by ATRP reaction.

[0053] Example 2

[0054] Take 5 mg of MC@PDA-SH@BA-MIPs, add 5 mL of NRG solution with a concentration of 35 mg / L and a pH value of 7.4, and place it in a 308 K water bath for oscillation. The contact time of the adsorbent and the solution is 5 to 360 min. The residual concentration of NRG at each time point is determined by UV-Vis method, and the adsorption capacity is calculated according to the measured results. As shown in Figure Figure 5 , MC@PDA-SH@BA-MIPs show rapid adsorption characteristics within 0 to 120 minutes, and the adsorption rate gradually slows down with time, and tends to adsorption equilibrium at 120 minutes. This is because as the time is prolonged, the imprinted cavity is gradually occupied by the target molecule, the adsorption capacity is continuously increased, until the equilibrium state is reached.

[0055] Take 5 mg MC@PDA-SH@BA-MIPs, add 5 mL of NRG solution with different concentrations (10, 15, 25, 35, 50 mg / L) (pH = 7.4) respectively, and oscillate in a constant temperature water bath at 25, 30 and 35 °C for 360 minutes. After the adsorption reaction is completed, the residual concentration of NRG is determined by UV-Vis method, and the adsorption capacity is calculated according to the measured data. The same method is used to calculate the adsorption capacity of MC@PDA-SH@BA-MIPs. As shown in Figure 6 Figure 6, under different initial concentrations and temperature conditions, the adsorption capacity of boron affinity porous microsphere imprinting adsorbent MC@PDA-SH@BA-MIPs gradually increases with the increase of temperature, indicating that the adsorption type of NRG on MC@PDA-SH@BA-MIPs is endothermic reaction.

[0056] Example 3

[0057] 5.0 mg MC@PDA-SH@BA-MIPs were immersed in 5.0 mL of the above hydroxyl compound aqueous solution (pH = 7.4, concentration 35 mg / L) respectively, and these compounds included rutin, quercetin, o-nitrophenol, alizarin red and p-benzenediol. Subsequently, the mixture was subjected to adsorption in a 308 K water bath for 6.0 hours, after the adsorption was completed, the supernatant was separated by centrifugation, and the concentration of the competitive molecule was determined by UV-Vis method. As shown in Figure 7 Figure 7, compared with other competitors, the adsorption capacity of MC@PDA-SH@BA-MIPs for NRG is significantly stronger, which is attributed to the rich imprinting recognition sites on its surface, indicating that the material has significant specific recognition ability for NRG.

Claims

1. A method for preparing a high-activity, hierarchically porous, boronic acid-imprinted hydrogel microsphere adsorbent, characterized in that, Comprising the following steps: (1) 1,3,5-tris(4-aminophenyl)benzene and 1,3,5-triformaldehyde benzene are dissolved in a three-necked flask containing acetonitrile, then chiral phosphate-based benzaldehyde aniline is added and dispersed in an ultrasonic water bath; then, under the protection of nitrogen, Sc(OTfs)3-containing acetonitrile is continuously added, and the first mechanical stirring is carried out; then, the obtained product BTCA-COFs is washed with acetonitrile and dried in vacuum; Dopamine hydrochloride is dissolved in Tris-HCl buffer solution, and the pH is adjusted with sodium hydroxide solution; then, BTCA-COFs is added to the solution, and the second stirring is carried out; then, the obtained product is washed with methanol for several times, centrifuged, dried, and named as BTCA-COF@PDA; (2) BTCA-COF@PDA is dispersed in ultrapure water, then 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride and N-hydroxysuccinimide are added, stirred, then mercaptoacetic acid is added, and the mixture is stirred; finally, the obtained sample is washed with ultrapure water and dried in vacuum, and the final product is named as BTCA-COF@PDA-SH; (3) BTCA-COF@PDA-SH is uniformly dispersed in mesitylene, then Sc(OTf)3 is added dropwise, and the mixture is subjected to high-speed shearing to obtain a stable oil-in-water (O / W) type Pickering emulsion; (4) The Pickering emulsion is transferred to a centrifuge tube, mesitylene is added, then 1,3,5-tris(4-aminophenyl)benzene, 1,3,5-triformaldehyde benzene are dissolved in chloroform, and a competitor benzaldehyde and aniline are added to prepare an emulsion dispersion; the mixture is placed in a centrifuge tube and left to stand at room temperature, and the obtained microspheres are named as MC BTCA-COF@PDA-SH; (5) Functional monomer 3-acrylamidophenylboronic acid, template molecule NRG and methanol are added to a flask, mixed and stirred for pre-assembly; then, polydi-pentaerythritol five acrylate and benzoin dimethyl ether are added and subjected to ultrasonic treatment; then, the prepared MC BTCA-COF@PDA-SH is added to the mixed solvent, and nitrogen treatment is carried out to prevent oxidation; molecularly imprinted polymerization is initiated by ultraviolet light, after the reaction is completed, the template molecule NRG is removed by washing with methanol and acetic acid solution, then the product is washed with ethanol and deionized water for several times, and finally the product is dried in an oven to obtain a high-activity multi-level hole boronic acid imprinted hydrogel microsphere adsorbent, which is abbreviated as MC@PDA-SH@BA-MIPs.

2. The production method according to claim 1, wherein In step (1), the amount ratio of 1,3,5-tris(4-aminophenyl)benzene, 1,3,5-triformaldehyde benzene, acetonitrile, chiral phosphate-based benzaldehyde, aniline and Sc(OTfs)3 is 17.6 mg:8.1 mg:39 mL:60.8 μL:54.4 μL:11.8 mg; the ultrasonic water bath dispersion time is 30 minutes; the first mechanical stirring temperature is 25℃, and the time is 24 h; the vacuum drying temperature is 60℃, and the drying time is 24 h.

3. The production method according to claim 1, wherein In step (1), the dosage ratio of BTCA-COFs and dopamine hydrochloride was 100 mg:75 mg; the concentration of Tris-HCl buffer was 10 mmol / L; the pH was adjusted to 8.5 with sodium hydroxide solution; the temperature for the second stirring was 25℃, and the time was 6 h.

4. The production method according to claim 1, wherein In step (2), the dosage ratio of BTCA-COF@PDA, 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride, N-hydroxysuccinimide and mercaptoacetic acid was 20 mg:10 mL:10 mL:52 μL. In step (2), after the addition of mercaptoacetic acid, the mixture was stirred at 25℃ for 12 h.

5. The production method according to claim 1, wherein In step (3), the dosage ratio of BTCA-COF@PDA-SH, mesitylene and Sc(OTf)3 was 1.7 mg:4.0 mL:0.2 mL; the rate of high-speed shearing was 15000 rpm, and the shearing time was 3 min.

6. The production method according to claim 1, wherein In step (3), in step (4), the dosage ratio of Pickering emulsion, mesitylene, 1,3,5-tris(4-aminophenyl) benzene, 1,3,5-triformylbenzene, chloroform, benzaldehyde and aniline was 2.0 mL:4.0 mL:3.5 mg:1.6 mg:2.0 mL:12.1 μL:10.8 μL; the time for room temperature standing was 24 h.

7. The production method according to claim 1, wherein In step (5), the dosage ratio of 3-acrylamidophenylboronic acid, NRG, methanol, polydi-pentaerythritol five acrylate, benzoin dimethyl ether, MC BTCA-COF@PDA-SH was 38 mg:29 mg:20.0 mL:58 mg:20 mg:80 mg.

8. The production method according to claim 1, wherein In step (5), the pre-assembly time was 3.0 h, the ultrasonic treatment time was 10 min; the nitrogen treatment time was 30 min; the molecularly imprinted polymerization was initiated by 365 nm ultraviolet light for 60 min; In the methanol and acetic acid solution, the volume ratio of methanol and acetic acid was 9:

1.

9. A high activity, hierarchically porous, boronic acid-imprinted hydrogel microsphere adsorbent, characterized in that, is prepared by the preparation method of any one of claims 1-8.

10. Use of the high-activity hierarchical porous boronic acid imprinted hydrogel microsphere adsorbent MC@PDA-SH@BA-MIPs of claim 9 for adsorbing and separating flavonoid naringin NRG.

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