Zearalenone functionalized graphene surface molecularly imprinted material, preparation method therefor and use thereof

Abstract

A zearalenone functionalized graphene surface molecularly imprinted material, a preparation method therefor and the use thereof, which belong to the technical field of molecularly imprinted materials. The zearalenone functionalized graphene surface molecularly imprinted material is prepared by using RGO as a carrier, CDHB as a template molecule, 1-ALPP as a functional monomer, TRIM as a cross-linking agent, AIBN as an initiator, and acetonitrile as a pore-forming agent.

Claims

1. A zearalenone functionalized graphene surface molecularly imprinted material, which has reduced graphene oxide (RGO) as a carrier, cyclododecyl 2,4-dihydroxybenzoate (CDHB) as a template molecule, 1-allylpiperazine (1-ALPP) as a functional monomer, trimethylolpropane triacrylate (TRIM) as a cross-linking agent, azodiisobutyronitrile (AIBN) as an initiator, and acetonitrile as a pore-forming agent; wherein the zearalenone functionalized graphene surface molecularly imprinted material is prepared by a preparation method comprising the following steps: adding CDHB, 1-ALPP, TRIM, AIBN and acetonitrile to a solvent in sequence to provide a first mixture, mixing the first mixture uniformly, injecting nitrogen to remove oxygen and sealing the first mixture, and subjecting the first mixture to ultraviolet light irradiation for 24 h or 60 C. water bath for constant-temperature reaction for 24 h to obtain a molecularly imprinted polymer, wherein the solvent is N,N-dimethylformamide (DMF); grinding the molecularly imprinted polymer, sieving it through a 100-200 mesh screen, and removing CDHB with an eluent to provide a product, drying the product at 40 C. overnight, to obtain a template-removed molecularly imprinted polymer; and dispersing graphene oxide (GO) into water or DMF, adding the template-removed molecularly imprinted polymer to provide a second mixture, subjecting the second mixture to ultrasound and mixing it uniformly, then adding hydrazine hydrate to provide a third mixture, heating the third mixture in a 90-95 C. water bath for 4-6 h, cooling the third mixture to room temperature, filtering the third mixture to obtain a powder, then washing the powder with water and ethanol in sequence for a plurality of times, and drying the powder at 60 C. for 1-2 h to obtain the zearalenone functionalized graphene surface molecularly imprinted material.

2. The zearalenone functionalized graphene surface molecularly imprinted material according to claim 1, wherein a molar ratio of CDHB:1-ALPP:TRIM is 1:4-8:20, an addition amount of AIBN is 10-20% weight of 1-ALPP, and a molar amount to volume ratio of CDHB and acetonitrile is 1 mol:10-30 mL.

3. The zearalenone functionalized graphene surface molecularly imprinted material according to claim 1, wherein the eluent is a mixture of methanol and acetic acid with a volume ratio of 96:4.

4. The zearalenone functionalized graphene surface molecularly imprinted material according to claim 1, wherein an addition amount of the GO is 0.1-0.5% weight of the template-removed molecularly imprinted polymer, a concentration of the hydrazine hydrate is 1-10%, and an addition volume to weight ratio of hydrazine hydrate and GO is 1-2 L: 1 mg.

5. The zearalenone functionalized graphene surface molecularly imprinted material according to claim 4, wherein a mass ratio of the GO to the template-removed molecularly imprinted polymer is 0.3%.

6. The zearalenone functionalized graphene surface molecularly imprinted material according to claim 1, wherein a preparation method for the CDHB is prepared by a preparation method that comprises the following steps: using 2,4-dihydroxybenzoic acid and cyclododecanol as raw materials, N,N-carbonyldiimidazole (CDI) as an activator, 1,8-diazabicyclo[5.4.0] undec-7-ene (DBU) as a catalyst and DMF as a solvent to provide a reaction mixture, subjecting the reaction mixture to reaction at 40-60 C. for 18-24 h, separating an organic phase, drying the organic phase, and removing the solvent by evaporation under reduced pressure, to obtain a crude product of yellowish solid; and purifying the crude product using a high-performance counter-current chromatography method or a preparative liquid chromatography method, wherein the high-performance counter-current chromatography method selects a mobile phase of a mixture of n-hexane, ethyl acetate, methanol and water with a volume ratio of 1:0.2:1:0.2, a mobile phase flow rate of 2 mL/min, a rotational speed of 800 r/min, a loading volume of 10 mL, a loading mass concentration of 20 mg/mL, and a detection wavelength of 254 nm; the preparative liquid chromatography method selects a mobile phase of a mixture of water and acetonitrile with a volume ratio of 40:60, a detection wavelength of 254 nm, and a flow rate of 16 mL/min.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) In order to illustrate the embodiments in the present disclosure or the technical solutions in the prior art more clearly, the drawings used in the description of the embodiments or the prior art is briefly described below. It should be apparent that the drawings in the following description are merely illustrative, and for those skilled in the art, other drawings of embodiments can be obtained according to the drawings provided without creative efforts.

(2) FIG. 1 is an image from scanning electron microscope (SEM) showing the template-removed molecularly imprinted polymer (denoted as MIP) prepared in the second step of Example 3;

(3) FIG. 2 is an image from scanning electron microscope (SEM) showing the zearalenone functionalized graphene surface molecularly imprinted material (denoted as RGO-MIP) prepared in Example 3;

(4) FIG. 3 is X-ray photoelectron spectra (X-ray photoelectron spectroscopy, XPS) of MIP and RGO-MIP, in which the C/O ratio of RGO-MIP was higher than MIP, indicating that the functionalized graphene did exist in RGO-MIP. Compared with MIP, RGO-MIP had the appearance of CO and the increase of CC, CO (epoxy group) and COH, indicating that the functionalized graphene was successfully introduced on MIP, and under the reduction effect of hydrazine hydrate, OCO disappeared, and GO was reduced to RGO;

(5) FIG. 4 shows the comparison among ZEN adsorption performance of three polymers at different adsorption time;

(6) FIG. 5 shows the adsorption kinetic model of the zearalenone functionalized graphene surface molecularly imprinted material provided by an embodiment in the present disclosure.

DETAILED DESCRIPTION

(7) The implementation of the present disclosure is further described below through specific embodiments, and those skilled in the art can easily ascertain other advantages and effects of the present disclosure through the content disclosed by the description; apparently, the embodiments described are merely a part of the embodiments in the present disclosure, and not all of the embodiments. Based on the embodiments in the present disclosure, any embodiment obtained by those skilled in the art without creative efforts shall fall within the protection scope of the present disclosure.

(8) For those without specific technique or condition indicated, the embodiments are performed according to the technique or condition described in the literature in the field, or according to the product specification. For those without manufacturer indicated, the reagents or instruments are all conventional products that can be commercially purchased through regular channels.

Example 1

(9) This example provides a preparation method for the zearalenone functionalized graphene surface molecularly imprinted material, including the following steps: 20.0 mg of RGO was dispersed into 20 mL of DMF under ultrasound, 4.0 mg of N-vinylcarbazole was added into the same, the mixture was subjected to ultrasound for 2 h and mixed uniformly, then 320.0 mg of CDHB, 504.8 mg of 1-ALPP and 10 mL of acetonitrile were added, and after the mixture was allowed to stand for 15 min, 5.9264 g of TRIM and 77.2 mg of AIBN were added, and after the system was mixed uniformly, nitrogen was injected for 30 min, and the sealed reaction vessel was placed under ultraviolet light (=254 nm) irradiation for 24 h, so as to obtain a functionalized graphene surface molecularly imprinted polymer (being gray-black and hard); and the obtained polymer was ground in a mortar and sieved through a 200 mesh screen, and with a mixture of methanol/acetic acid=96/4 (v/v) as an eluent, the polymer was subjected to reflux for a plurality of times to remove CDHB, and then placed in an oven and dried at 40 C. overnight, so as to obtain the zearalenone functionalized graphene surface molecularly imprinted material.

Example 2

(10) This example provides a preparation method for the zearalenone functionalized graphene surface molecularly imprinted material, including the following steps: 20.0 mg of RGO was dispersed into 20 mL of DMF under ultrasound, 4.0 mg of N-vinylcarbazole was added into the same, the mixture was subjected to ultrasound for 2 h and mixed uniformly, then 320.0 mg of CDHB, 757.2 mg of 1-ALPP and 10 mL of acetonitrile were added, and after the mixture was allowed to stand for 15 min, 5.9264 g of TRIM and 77.2 mg of AIBN were added, and after the system was mixed uniformly, nitrogen was injected for 30 min, and the sealed reaction vessel was placed in 60 C. water bath for constant-temperature reaction for 24 h, so as to obtain a functionalized graphene surface molecularly imprinted polymer (being gray-black and hard); and the obtained polymer was ground in a mortar and sieved through a 200 mesh screen, and with a mixture of methanol/acetic acid=96/4 (v/v) as an eluent, the polymer was subjected to reflux for a plurality of times to remove CDHB, and then placed in an oven and dried at 40 C. overnight, so as to obtain the zearalenone functionalized graphene surface molecularly imprinted material.

Example 3

(11) This example provides a preparation method for the zearalenone functionalized graphene surface molecularly imprinted material, including the following steps: 320.0 mg of CDHB, 504.8 mg of 1-ALPP and 10 mL of acetonitrile were added into 20 mL DMF in sequence, and after the mixture was allowed to stand for 15 min, 5.9264 g of TRIM and 77.2 mg of AIBN were added, and after the system was mixed uniformly, nitrogen was injected for 30 min, and the sealed reaction vessel was placed under ultraviolet light (=254 nm) irradiation for 24 h, so as to obtain a molecularly imprinted polymer (being gray-black and hard); the obtained polymer was ground in a mortar and sieved through a 200 mesh screen, and with a mixture of methanol/acetic acid=96/4 (v/v) as an eluent, the polymer was subjected to reflux for a plurality of times to remove CDHB, and then placed in an oven and dried at 40 C. overnight, so as to obtain a template-removed molecularly imprinted polymer; and 50 mg of the template-removed molecularly imprinted polymer and 0.15 mg of GO were added into 50 mL of water, subjected to ultrasound for 1 h and mixed uniformly, added with 20 L of 1% hydrazine hydrate, heated in a water bath at 95 C. for 4 h, cooled to room temperature, and filtered to obtain powder, and then the powder was washed by water and ethanol in sequence for a plurality of times, dried in an oven at 60 C. for 2 h, so as to obtain the zearalenone functionalized graphene surface molecularly imprinted material.

Example 4

(12) This example provides a preparation method for the zearalenone functionalized graphene surface molecularly imprinted material, including the following steps: 320.0 mg of CDHB, 1009.6 mg of 1-ALPP and 10 mL of acetonitrile were added into 20 mL DMF in sequence, and after the mixture was allowed to stand for 15 min, 5.9264 g of TRIM and 77.2 mg of AIBN were added, and after the system was mixed uniformly, nitrogen was injected for 30 min, and the sealed reaction vessel was placed in 60 C. water bath for constant-temperature reaction for 24 h, so as to obtain a molecularly imprinted polymer (being gray-black and hard); the obtained polymer was ground in a mortar and sieved through a 200 mesh screen, and with a mixture of methanol/acetic acid=96/4 (v/v) as an eluent, the polymer was subjected to reflux for a plurality of times to remove CDHB, and then placed in an oven and dried at 40 C. overnight, so as to obtain a template-removed molecularly imprinted polymer; and 50 mg of the template-removed molecularly imprinted polymer and 0.15 mg of GO were added into 50 mL of DMF, subjected to ultrasound for 1 h and mixed uniformly, added with 20 L of 1% hydrazine hydrate, heated in a water bath at 95 C. for 6 h, cooled to room temperature, and filtered to obtain powder, and then the powder was washed by water and ethanol in sequence for a plurality of times, dried in an oven at 60 C. for 2 h, so as to obtain the zearalenone functionalized graphene surface molecularly imprinted material.

Example 5

(13) The preparation method for the zearalenone functionalized graphene surface molecularly imprinted material provided in this example differs from Example 3 only in that: an addition amount of GO was 0.05 mg.

Example 6

(14) The preparation method for the zearalenone functionalized graphene surface molecularly imprinted material provided in this example differs from Example 3 only in that: an addition amount of GO was 0.25 mg.

Comparative Example 1

(15) The preparation method for the zearalenone functionalized graphene surface molecularly imprinted material provided in this comparative example differs from Example 3 only in that: 20 L of 1% hydrazine hydrate was replaced with 6.25 mg ascorbic acid.

Comparative Example 2

(16) The preparation method for the zearalenone functionalized graphene surface molecularly imprinted material provided in this example differs from Example 3 only in that: the reducing agent of hydrazine hydrate was not added.

Test Example 1

(17) Test for ZEN adsorption capacity of the zearalenone functionalized graphene surface molecularly imprinted materials prepared in Examples 1-6 and Comparative Examples 1-2.

(18) Eight samples of 0.5 ppm ZEN acetonitrile solution of 5 mL were taken, added with the above materials of the same amount respectively, subjected to ultrasound and stirred until reaching adsorption equilibrium, and then the effect of different modification methods on the adsorption capacity were investigated.

(19) The adsorption capacity was evaluated by the adsorption rate (Q): Q=(C.sub.0C.sub.t)/C.sub.0*100%, in which C.sub.0 and C.sub.t represented the initial concentration and the adsorption equilibrium concentration of ZEN (mg.Math.L.sup.1), respectively. The results are shown in Table 1.

(20) TABLE-US-00001 TABLE 1 Addition amount of the Adsorption rate molecularly imprinted material/mg of the sample 1 mg 3 mg 5 mg 10 mg 15 mg Example 1 21% 33% 68% 92% 95% Example 2 15% 30% 54% 88% 90% Example 3 23% 46% 78% 97% 100% Example 4 13% 26% 49% 71% 83% Example 5 20% 41% 70% 89% 93% Example 6 18% 37% 65% 78% 88% Comparative Example 1 10% 21% 34% 58% 62% Comparative Example 2 24% 45% 73% 95% 97%

(21) The results show that: with the increase of RGO content, the adsorption capacity of RGO-MIP would increase, and when the RGO content was 0.3%, the adsorption effect of the obtained RGO-MIP was the best, and with the continuous increase of RGO ratio, the adsorption capacity would decrease instead. Because the surface malleability of RGO will increase the contact area between MIP and target molecules, the adsorption capacity increases with the increase of RGO content, but when the content of RGO is too high, RGO will cover the specific binding sites on the MIP surface, turn to affect it specifically binding to the target molecules; thereby the optimal ratio of RGO was 0.3%.

(22) The ascorbic acid used in Comparative Example 1 has a weak reducing effect and cannot completely reduce GO, which will affect the adsorption effect; meanwhile, since there may be residual ascorbic acid on the material surface, its hydroxyl group will also inhibit the ZEN adsorption of the material.

(23) GO has the similar circumstance with RGO; the surface malleability of GO will increase the contact area between MIP and target molecules, allowing more binding sites to be exposed, and meanwhile, the groups on GO surface, such as carboxyl and hydroxyl groups, may also bind to target molecules through hydrogen bonds or electrostatic interactions; hence, under the condition that there only existed the target molecule (ZEN), Comparative Example 2 also showed a good adsorption effect.

Test Example 2

(24) Test for ZEN specific adsorption capacity of the zearalenone functionalized graphene surface molecularly imprinted materials prepared in Examples 1 and 3 and Comparative Example 2.

(25) A mixture solution of ZEN and deoxynivalenol (DON) with a certain concentration (containing 0.5 ppm of each one) was prepared, and added with GO-MIP and RGO-MIP of the same amount (10 mg), respectively. The adsorption capacity was evaluated by the adsorption rate (Q): Q=(C.sub.0C.sub.t)/C.sub.0*100%, in which C.sub.0 and C.sub.t represented the initial concentration and the adsorption equilibrium concentration of ZEN (mg.Math.L.sup.1), respectively. The results are shown in Table 2.

(26) TABLE-US-00002 TABLE 2 Adsorption time Sample Substance 0 min 10 min 15 min 30 min Example 1 ZEN 0 51% 85% 92% DON 0 4% 4% 5% Example 3 ZEN 0 55% 92% 97% DON 0 2% 2% 2% Comparative ZEN 0 46% 77% 84% Example 2 DON 0 33% 38% 40%

(27) The results show that: the molecularly imprinted material in Comparative Example 2 had a weak specific adsorption capacity for ZEN, indicating that the zearalenone functionalized graphene surface molecularly imprinted material provided in the present disclosure had a strong specific adsorption capacity for ZEN.

(28) GO has oxygen-containing functional groups on its surface, and is prone to adsorb ZEN, DON and other compounds with hydroxyl functional groups indistinguishably, and after GO is reduced to RGO, its oxygen-containing functional groups will decrease or disappear, and the adsorption effect mainly comes from the molecularly imprinted material, thereby improving the specific adsorption capacity for ZEN.

Test Example 3

(29) A ZEN solution with a certain concentration was prepared, and 10 mg of the zearalenone functionalized graphene surface molecularly imprinted material prepared in Example 3 (denoted as RGO-MIP) (see FIG. 2 for SEM), the template-removed molecularly imprinted polymer prepared in the second step of Example 3 (denoted as MIP) (see FIG. 1 for SEM) and NIP (namely, the blank control without CDHB added during preparation) were added to 100 mL of ZEN solution (0.5 ppm), respectively, and subjected to ultrasound and stirred for absorption for 5 h. Samples were taken every 1 h and loaded in a liquid chromatography for detection. The adsorption capacity (q.sub.e) of the polymer for ZEN was calculated. The q.sub.e was calculated according to the following formula:
q.sub.e=(C.sub.0C.sub.t)V/m
in which C.sub.0 and C.sub.t represented the initial concentration of ZEN (mg.Math.L.sup.1) and the adsorption equilibrium concentration of ZEN (mg.Math.L.sup.1) at a certain moment, respectively, V represented the solution volume (L), and m represented the mass of the adsorbent (g).

(30) FIG. 4 shows the comparison among ZEN adsorption performance of three polymers at different adsorption time.

(31) To further investigate the adsorption mechanism of the zearalenone functionalized graphene surface molecularly imprinted material of embodiments in the present disclosure, the pseudo-first-order and pseudo-second-order models were used for fitting, respectively. As can be seen from FIG. 5, the pseudo-second-order kinetic model was more suitable for the adoption kinetics.

(32) As shown in the results, the adsorption performances of RGO-MIP and MIP were both better than NIP. According to the formation principle of molecularly imprinted polymer, it can be inferred that after CDHB is added, CDHB and the functional monomers are combined under hydrogen bonds, and then form the polymer with the help of ultraviolet light under the effect of the cross-linking agent and the initiator. When CDHB is removed from the polymer by being dissolved in the solution, the polymer surface will form hole sites with similar structure to ZEN, so that ZEN can effectively bind to the holes on polymer surface. The adsorption performance of RGO-MIP was better than MIP, indicating that the introduced graphene exerted some effects.

(33) According to the network structure of graphene, when CDHB are mixed with graphene solution, CDHB is introduced on the graphene substrate, binds to functional monomers under hydrogen bonds at the same time, and further forms the polymer on the graphene surface. This structure allows the polymer to stretch more fully on the carrier surface, and after the template is removed, more hole sites are thus exposed, so that under the same conditions, RGO-MIP could adsorb more ZEN molecules.

Example 7

(34) This example provides a preparation method for a filler of a ZEN molecularly imprinted solid-phase extraction small column, including the following steps: 20.0 mg of RGO was dispersed into 20 mL of DMF under ultrasound, 4.0 mg of N-vinylcarbazole was added into the same, the mixture was subjected to ultrasound for 2 h and mixed uniformly, then 320.0 mg of CDHB, 504.8 mg of 1-ALPP and 10 mL of acetonitrile were added, and after the mixture was allowed to stand for 15 min, 5.9264 g of TRIM and 77.2 mg of AIBN were added, and after the system was mixed uniformly, nitrogen was injected for 30 min, and the sealed reaction vessel was placed under ultraviolet light (=254 nm) irradiation for 24 h, so as to obtain a functionalized graphene surface molecularly imprinted polymer (being gray-black and hard); and the obtained polymer was ground in a mortar and sieved through a 200 mesh screen, and with a mixture of methanol/acetic acid=96/4 (v/v) as an eluent, the polymer was subjected to reflux for a plurality of times to remove CDHB, and then placed in an oven and dried at 40 C. overnight, so as to obtain a zearalenone functionalized graphene surface molecularly imprinted material.

(35) Preparation and performance evaluation of the ZEN molecularly imprinted solid-phase extraction small column 50 mg of the zearalenone functionalized graphene surface molecularly imprinted material prepared in this example was accurately weighted out, and packed into a solid-phase extraction small column by a wet method, and then both ends of the column were capped by mesh pieces of polytetrafluoroethylene. Before use, the column was activated with 10 mL of methanol, and then washed with 10 mL of deionized water. 3 mL extraction solution (the ZEN concentration was 0.5 mg/L) of ZEN-containing sample was transferred to the above activated solid-phase extraction small column, and the flow rate was controlled at 1 drop/s. After the sample was drained, 10 mL of methanol/water (5/95, V/V) mixture was added for washing, and the washing liquid was discarded. The small column was drained, and then 10 mL of methanol was added to elute. All the eluents were collected, dried by nitrogen blowing, then dissolved by 2 mL methanol and brought to a certain volume, and after the solution was filtered with a 0.22 m filter, it was loaded in a high performance liquid chromatography for detection.

(36) The results show that: the ZEN molecularly imprinted solid-phase extraction small column provided in this example had a recovery rate reaching 100% for ZEN, and had a significant purification effect for the complex matrix.

Example 8

(37) This example provides a preparation method for a filler of a ZEN molecularly imprinted solid-phase extraction small column, including the following steps: 320.0 mg of CDHB, 504.8 mg of 1-ALPP and 10 mL of acetonitrile were added into 20 mL DMF in sequence, and after the mixture was allowed to stand for 15 min, 5.9264 g of TRIM and 77.2 mg of AIBN were added, and after the system was mixed uniformly, nitrogen was injected for 30 min, and the sealed reaction vessel was placed under ultraviolet light (=254 nm) irradiation for 24 h, so as to obtain a molecularly imprinted polymer (being gray-black and hard); the obtained polymer was ground in a mortar and sieved through a 200 mesh screen, and with a mixture of methanol/acetic acid=96/4 (v/v) as an eluent, the polymer was subjected to reflux for a plurality of times to remove CDHB, and then placed in an oven and dried at 40 C. overnight, so as to obtain a template-removed molecularly imprinted polymer; and 50 mg of the template-removed molecularly imprinted polymer and 0.15 mg of GO were added into 50 mL of water, subjected to ultrasound for 1 h and mixed uniformly, added with 20 L of 1% hydrazine hydrate, heated in a water bath at 95 C. for 4 h, cooled to room temperature, and filtered to obtain powder, and then the powder was washed by water and ethanol in sequence for a plurality of times, dried in an oven at 60 C. for 2 h, so as to obtain a zearalenone functionalized graphene surface molecularly imprinted material.

(38) The ZEN molecularly imprinted solid-phase extraction small column was prepared using the same method provided in Example 7 and evaluated on its performance. The results show that: the ZEN molecularly imprinted solid-phase extraction small column provided in this example had a recovery rate reaching 100% for ZEN, and had a significant purification effect for the complex matrix.

Example 9

(39) This example provides a preparation method for a ZEN-specifically-entrapping mesh, including the following steps: (1) pretreatment: a stainless steel metal mesh with a pore size of 100 mesh was subjected to ultrasonic cleaning in acetone, deionized water and ethanol for 20 min in sequence, dried in an oven at 60 C., then soaked in a diluted chlorhydric acid solution with a concentration of 5% for 2 h, taken out and then rinsed with deionized water for a plurality of times, and dried in an oven at 60 C.; (2) preparation of a graphene molecularly imprinted material film-forming solution: 20.0 mg of RGO was dissolved completely into 20 mL of DMF under ultrasound, and then 320.0 mg of CDHB, 504.8 mg of 1-ALPP, 5.9264 g of TRIM, 77.2 mg of AIBN and 10 mL acetonitrile were added in sequence, and stirred under N.sub.2 atmosphere for 30 min until being dissolved completely, so as to obtain the film-forming solution for later use; and (3) the stainless steel metal mesh treated by step (1) was soaked in the film-forming solution of step (2) for 5 min and then pulled out at a speed of 2 mm/s, the operation was repeated continuously for 5 times, so as to form a uniform film on the surface of the stainless steel metal mesh, the stainless steel metal mesh was placed in a wide-mouth glass vessel, nitrogen was injected to remove oxygen for 15 min, the vessel mouth was sealed, and under N.sub.2 protection, the mesh was subjected to constant-temperature reaction at 65 C. for 8 h, cooled to room temperature, then subjected to reflux with a mixture of methanol/acetic acid=96/4 (v/v) until CDHB was removed completely, then soaked and washed with deionized water and ethanol repeatedly for a plurality of times, and dried in an oven at 60 C., so as to obtain the ZEN-specifically-entrapping mesh.

(40) Performance evaluation of the ZEN-specifically-entrapping mesh The ZEN-specifically-entrapping mesh prepared in this example was packed in the head part of the solvent filter, and 100 mL of ZEN-containing liquid sample (the ZEN concentration was 0.5 mg/L) was led to flowing through the mesh, controlling the flow rate to guarantee that all the sample flowed through using about 15 min. The ZEN content of the solution was detected after passing through the mesh.

(41) The removal rate was represented by F: F=(C.sub.0C.sub.t)/C.sub.0*100%, in which CO and C.sub.t represented the concentration of ZEN in the sample (mg.Math.L.sup.1) before and after passing through the mesh, respectively.

(42) The results show that: the ZEN-specifically-entrapping mesh provided in this example had a removal rate reaching 100% for ZEN in the sample solution.

Example 10

(43) This example provides a preparation method for a ZEN-specifically-removing molecularly imprinted sphere, including the following steps: (1) preparation of a graphene molecularly imprinted material film-forming solution: 20.0 mg of RGO was dissolved completely into 20 mL of DMF under ultrasound, and then 320.0 mg of CDHB, 504.8 mg of 1-ALPP, 5.9264 g of TRIM, 77.2 mg of AIBN and 10 mL acetonitrile were added into the solvent in sequence, and mixed uniformly, and nitrogen was injected to remove oxygen followed by sealing; and (2) silica spheres with a diameter of 5 mm were soaked in the film-forming solution of step (1), and placed in a wide-mouth glass vessel, and nitrogen was injected to remove oxygen for 15 min, the vessel mouth was sealed, and under N.sub.2 protection, the silica spheres was subjected to constant-temperature reaction at 60 C. for 8 h, cooled to room temperature, then taken out, removed the extra polymer attached on the surface, then subjected to reflux with a mixture of methanol/acetic acid=96/4 (v/v) until the template molecules were removed completely, soaked and washed with deionized water and ethanol repeatedly for a plurality of times, and dried in an oven at 60 C., so as to obtain the ZEN-specifically-removing molecularly imprinted sphere.

(44) Performance evaluation of the ZEN-specifically-removing molecularly imprinted sphere Fifty ZEN-specifically-removing molecularly imprinted spheres prepared above were taken and put into a liquid sample of 100 mL containing ZEN (the ZEN concentration was 0.5 mg/L), stirred and blended for 15 min, and the imprinted spheres were filtered out, and the ZEN content of the filtrate was detected.

(45) The adsorption capacity of the specifically molecularly imprinted sphere was evaluated by the adsorption rate (Q): Q=(C.sub.0C.sub.t)/C.sub.0*100%, in which C.sub.0 and C.sub.t represented the concentration of ZEN in the sample (mg.Math.L.sup.1) before and after put the imprinted spheres, respectively.

(46) The results show that: the ZEN-specifically-removing molecularly imprinted sphere provided in this example had a adsorption capacity reaching 99% for ZEN in the sample solution.

(47) Although general description and specific embodiments have been used hereinabove to describe the present disclosure in detail, modifications or improvements can be made for those above based on the present disclosure, which is apparent to those skilled in the art. Therefore, those modifications or improvements without departing from the spirit of the present disclosure all fall within the protection scope of the present disclosure.