High-affinity fluorine-functionalized graphene oxide composite material as well as preparation method and application thereof

Abstract

The invention provides a high-affinity fluorine-functionalized graphene oxide composite material as well as a preparation method and application thereof. The preparation method of the material comprises the following steps: by using vinyl trimethoxy silane as a functional modifier, firstly, growing and grafting vinyl trimethoxy silane on the surface of graphene oxide to obtain vinyl functionalized graphene oxide; synthesizing a final material in DMF (Dimethyl Formamide) by taking vinyl functionalized graphene oxide as a carrier material, taking a fluorinated eutectic solvent as a monomer and taking N, N '-methylene bisacrylamide as a cross-linking agent, and finally washing, freezing and drying to obtain the high-affinity fluorine functionalized graphene oxide composite material. The material prepared by the invention has rich adsorption mechanisms (F-F action, electrostatic adsorption action, hydrogen-bond action and pi-pi accumulation action), can be used for extracting and separating fluorine-containing pesticides (biphenyl bacteria amide, meconazole and trifloxystrobin) in traditional Chinese medicines, can also be used for extracting and separating anti-cancer active components (wogonin and chrysin) in the traditional Chinese medicines, and has wide application prospects. And multi-angle synchronous evaluation of the quality of the traditional Chinese medicine is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of composite materials, and specifically to a highly affinity fluorinated functionalized graphene oxide composite material, a preparation method thereof, and an application thereof. Background Art

[0002] Deep eutectic solvents (DESs) are emerging green solvents that have been widely used in the separation and analysis of target analytes in complex matrix samples. However, in-depth studies on DESs have found that there are still some deficiencies in their use as extraction and separation solvents: they have high viscosity and are not easily dispersed, and their extraction and separation performance for target analytes is limited.

[0003] Graphene oxide (GO) has a large specific surface area and abundant oxygen-containing functional groups on its surface, making it easy to be functionalized to prepare GO composite materials with high adsorption performance. At present, GO composite materials have been widely used in the field of drug analysis. Chinese Invention Patent (Application No. 201910796496.0) discloses a deep eutectic solvent functionalized graphene oxide, a preparation method thereof, and an application thereof. The obtained material has good dispersibility and stability in aqueous solution and can be used as an adsorbent for the extraction and separation of pyrethroid pesticides in Curcuma wenyujin. Thus, the use of DESs as functionalizing modifiers to modify the surface of GO has received extensive attention from researchers. However, most of the existing traditional deep eutectic solvent / graphene oxide composite materials adopt non-covalent grafting methods, which have problems of incomplete and insecure grafting of deep eutectic solvents. Summary of the Invention

[0004] The purpose of the present invention is to provide a highly affinity fluorinated functionalized graphene oxide composite material, a preparation method thereof, and an application thereof. The composite material has strong hydrogen bond interactions and highly affinity F–F interactions, and can solve the problems of interference of complex sample matrices on the extraction and separation of target substances and incomplete and insecure grafting of deep eutectic solvents caused by non-covalent grafting in traditional deep eutectic solvent / graphene oxide composite materials.

[0005] The present invention is achieved as follows:

[0006] A highly affinity fluorinated functionalized graphene oxide composite material is prepared by a free radical polymerization reaction in an N,N-dimethylformamide organic system, using a fluorinated deep eutectic solvent as a monomer, N,N'-methylenebisacrylamide as a crosslinking agent, azobisisobutyronitrile as an initiator, and vinyl-functionalized graphene oxide as a substrate, and covalently modifying and connecting a fluorinated deep eutectic solvent molecular layer to the surface of the vinyl-functionalized graphene oxide.

[0007] Preferably, the fluorinated deep eutectic solvent is 2-fluoro-5-trifluoromethylaniline and 2-trifluoromethylacrylic acid.

[0008] In the process of preparing the composite material, vinyltrimethoxysilane is used as a bridge. In the free radical polymerization reaction, a fluorinated deep eutectic solvent containing double bonds is used as a monomer, and N,N'-methylenebisacrylamide is used as a crosslinking agent to improve the adsorption performance of graphene oxide. This highly affinity fluorinated graphene oxide composite material can not only extract and separate fluorinated pesticides (bixafen, trifloxystrobin, and triticonazole) in Scutellaria baicalensis, but also extract and separate anti-cancer active ingredients (wogonin and chrysin) in Scutellaria baicalensis.

[0009] The preparation method of the highly affinity fluorinated graphene oxide composite material provided by the present invention specifically includes the following steps:

[0010] (1) Ultrasonically disperse graphene oxide in a mixed solution composed of absolute ethanol and purified water, then add vinyltrimethoxysilane, and adjust the solution system to be alkaline. After the reaction is completed, wash and freeze-dry to obtain vinyl-functionalized graphene oxide;

[0011] (2) Add vinyl-functionalized graphene oxide into N,N-dimethylformamide solution and ultrasonically disperse it evenly; add the fluorinated deep eutectic solvent, N,N'-methylenebisacrylamide, and azobisisobutyronitrile into the vinyl-functionalized graphene oxide dispersion. After the reaction is completed, wash and freeze-dry to obtain the highly affinity fluorinated graphene oxide composite material.

[0012] Preferably, the preparation method of the fluorinated deep eutectic solvent in step (2) is as follows: Weigh an appropriate amount of 2-fluoro-5-(trifluoromethyl)aniline and 2-(trifluoromethyl)acrylic acid in a vial, and heat and stir at 80.0 °C for 0.5 - 1.0 h to obtain the fluorinated deep eutectic solvent.

[0013] More preferably, the molar ratio of 2-fluoro-5-(trifluoromethyl)aniline to 2-(trifluoromethyl)acrylic acid in step (2) is 1:2.

[0014] Preferably, the molar ratio of the fluorinated deep eutectic solvent to N,N'-methylenebisacrylamide in step (2) is 1:5 - 1:8.

[0015] Preferably, the ultrasonic time in steps (1) and (2) is 2 - 3 h, the ultrasonic frequency is 40 - 100 kHz, and the ultrasonic power is 100 - 500 W.

[0016] Preferably, the reaction conditions in step (2) are specifically: under nitrogen protection, at 70 °C, reacting for 24 h at 350 rpm.

[0017] Preferably, the reaction conditions in step (1) are specifically: reacting at 70 °C for 12 h.

[0018] The present invention provides a method for preparing a high-affinity fluorinated graphene oxide composite material based on graphene oxide. First, vinyltrimethoxysilane is used as a functionalizing reagent to modify graphene oxide. Then, by utilizing the double bonds of vinyltrimethoxysilane, DES, and the cross-linking agent, a graphene oxide composite material with a fluorinated deep eutectic solvent molecular layer on its surface is synthesized through a radical polymerization reaction in an N,N-dimethylformamide organic system.

[0019] The high-affinity fluorinated graphene oxide composite material prepared by the present invention can be used as an adsorbent for the extraction and separation of fluorine-containing pesticides and anti-cancer active ingredients in Scutellaria baicalensis.

[0020] The present invention has the following beneficial effects:

[0021] 1. The present invention synthesizes a novel fluorinated deep eutectic solvent and uses it as a functionalizing modifier, expanding the application scope of DES.

[0022] 2. The present invention modifies the novel fluorinated deep eutectic solvent as a functionalizing modifier on the surface of vinyl-functionalized graphene oxide (VGO), enriching the adsorption mechanism of GO (F–F interaction, hydrogen bond interaction, electrostatic adsorption interaction, and π–π stacking interaction).

[0023] 3. The high-affinity fluorinated graphene oxide composite material synthesized by the present invention has rich adsorption forces (F–F interaction, hydrogen bond interaction, electrostatic adsorption interaction, and π–π stacking interaction) and a cross-linked porous network structure. It can not only be used for the extraction and separation of anti-cancer active ingredients (wogonin and chrysin) in Scutellaria baicalensis, but also for the extraction and separation of fluorine-containing pesticides (boscalid, pyraclostrobin, and trifloxystrobin) in Scutellaria baicalensis, providing a new method for the multi-angle evaluation of the quality of traditional Chinese medicine. Description of the Drawings

[0024] Figure 1 Scanning electron microscope images of the high-affinity fluorinated graphene oxide composite material and graphene oxide material prepared in Example 1 at 2000 times magnification.

[0025] Figure 2 Infrared spectra of the high-affinity fluorinated graphene oxide composite material and graphene oxide material prepared in Example 1 in the wavenumber range of 500 - 4000 cm -1 Wave number range.

[0026] Figure 3 X-ray photoelectron spectroscopy of the high-affinity fluorinated graphene oxide composite material prepared in Example 1.

[0027] Figure 4Hydrophilicity characterization diagram of the highly affinity fluorinated graphene oxide composite prepared in Example 1; where a corresponds to the moment of T = 0 s, b corresponds to the moment of T = 0.967 s, and c corresponds to the moment of T = 1.333 s.

[0028] Figure 5 Adsorption amount comparison diagram of wogonin and chrysin, the anti-cancer active ingredients, between the highly affinity fluorinated graphene oxide composite prepared in Example 1 and commercial adsorbents.

[0029] Figure 6 Extraction recovery rate of wogonin and chrysin, the anti-cancer active ingredients, by the highly affinity fluorinated graphene oxide composite prepared in Example 1.

[0030] Figure 7 Extraction detection of wogonin and chrysin, the anti-cancer active ingredients, in Scutellaria baicalensis Georgi from different producing areas by the highly affinity fluorinated graphene oxide composite prepared in Example 1.

[0031] Figure 8 Extraction detection of fluorine-containing pesticides (boscalid, trifloxystrobin, and trifloxystrobin) in Scutellaria baicalensis Georgi by the highly affinity fluorinated graphene oxide composite prepared in Example 1.

[0032] Figure 9 Extraction recovery rate of wogonin and chrysin, the anti-cancer active ingredients, by the highly affinity fluorinated graphene oxide composite prepared in Comparative Example 1.

[0033] Figure 10 Extraction recovery rate of wogonin and chrysin, the anti-cancer active ingredients, by the highly affinity fluorinated graphene oxide composite prepared in Comparative Example 2. Detailed implementation mode

[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 used to limit the present invention. In the following embodiments, the processes and methods not described in detail are all conventional methods well known in the art, and the reagents used are all commercially available analytical pure or chemical pure.

[0035] Example 1

[0036] Weigh 200 mg of graphene oxide and ultrasonically disperse it in a mixed solution composed of 80 mL of absolute ethanol and 20 mL of purified water. The ultrasonic power is 150 W, the ultrasonic frequency is 45 kHz, and the ultrasonic time is 3 h to obtain a graphene oxide dispersion. Then add vinyltrimethoxysilane (1 mL) to the graphene oxide dispersion. After 10 min, slowly add 10 mL of ammonia water. Stir at 70.0 °C for 12 h and then wash with 95% ethanol and purified water respectively, and freeze-dry to obtain vinyl-functionalized graphene oxide.

[0037] Synthesis of fluorinated deep eutectic solvents: Weigh 1.5 mmol of 2-fluoro-5-(trifluoromethyl)aniline and 3.0 mmol of 2-(trifluoromethyl)acrylic acid, and heat and dissolve them in an 80 °C water bath.

[0038] Weigh 100 mg of vinyl-functionalized graphene oxide and add it to 28 mL of N,N-dimethylformamide (DMF), and sonicate for 3 h. Disperse the prepared fluorinated deep eutectic solvent with 1 mL of DMF and add it to the ultrasonically dispersed vinyl graphene oxide dispersion. Then, sequentially add 7.5 mmol of N,N'-methylenebisacrylamide and 50 mg of azobisisobutyronitrile. Under nitrogen protection, react at 70.0 °C and 350 rpm for 24 h. Then, wash with methanol and purified water respectively, and freeze-dry to obtain a high-affinity fluorinated graphene oxide composite material (FDESs-VGO).

[0039] Scanning electron microscopy tests were performed on graphene oxide and the FDESs-VGO prepared in this example, and the results are as Figure 1 shown. It can be seen from Figure 1 that graphene oxide exhibits a wrinkled sheet structure. With the growth of the vinyltrimethoxysilane and fluorinated deep eutectic solvent molecular layers on the surface of graphene oxide, the obtained FDESs-VGO exhibits a crosslinked and porous network structure, and the particle size is also larger.

[0040] Infrared spectroscopy tests were performed on graphene oxide and the FDESs-VGO obtained in this example, and the obtained results are as Figure 2 shown. Figure 2 Among them, the peak at 3400 cm –1 corresponds to the O–H of GO and FDESs-VGO, and the peak at 1715 cm –1 corresponds to the C=O of GO and FDESs-VGO. The results show that compared with GO, the O–H absorption peak and the C=O absorption peak of FDESs-VGO are enhanced. This is mainly because N,N'-methylenebisacrylamide and 2-(trifluoromethyl)acrylic acid contain carbonyl and hydroxyl groups, indicating that FDESs have successfully modified vinyl-functionalized graphene oxide. FDESs-VGO has an obvious benzene ring skeletal stretching vibration peak at 1623 cm –1 , which mainly comes from the benzene ring of 2-fluoro-5-(trifluoromethyl)aniline in FDESs. FDESs-VGO has obvious C–N stretching vibration peaks and C–F stretching vibration peaks at 1317 cm –1 and 1220 cm –1 . The appearance of these characteristic peaks indicates that FDESs have been successfully grafted onto the surface of VGO.

[0041] X-ray photoelectron spectroscopy was used to characterize the FDESs-VGO obtained in this example, and the obtained results are asFigure 3 as shown Figure 3 Among them, the peaks at 102.5, 283.1, 400.0, 530.7, and 687.4 eV are attributed to Si2p, C1s, N1s, O1s, and F1s respectively. The Si2p peak comes from vinyltrimethoxysilane, the C1s and O1s peaks come from GO and fluorinated deep eutectic solvents, and the N1s and F1s come from fluorinated deep eutectic solvents, indicating that elements C, N, F, O, and Si coexist in FDESs-VGO, and it is determined that the fluorinated deep eutectic solvent is successfully grafted onto the surface of vinyl graphene oxide.

[0042] The hydrophilicity of FDESs-VGO was tested using a water contact angle measuring instrument, and the results are as Figure 4 shown. After 1.333 s, the water droplet was completely immersed in the composite material. The water contact angle data indicates that after functional modification, FDESs-VGO still has good hydrophilicity.

[0043] Example 2

[0044] Using the FDESs-VGO prepared in Example 1 of the present invention as an adsorbent, its differences from other commercial adsorbent materials (Silica, C 18 , PSA) were investigated.

[0045] 2 mg of different adsorbent materials (Silica, C 18 , PSA, and FDESs-VGO) and 2 mL of a mixed standard solution of baicalein and chrysin at 20 μg / mL were added to a 10 mL centrifuge tube together, and then the centrifuge tube was placed in a constant temperature water bath shaker at 300 rpm (25.0 °C) and shaken for 12 h, then taken out, centrifuged at 4000 rpm, and the supernatant was treated with a 0.22 μm polytetrafluoroethylene syringe filter and then subjected to HPLC detection. The detector was an ultraviolet detector (detection wavelength was 280 nm), and the adsorption amounts of different types of adsorbents for the target analytes were calculated. The obtained results are as Figure 5 shown. As Figure 5 can be seen, FDESs-VGO has a relatively high adsorption capacity for the anti-cancer active substances in Scutellaria baicalensis (wogonin: 14.0 mg / g; chrysin: 13.5 mg / g), which is significantly higher than the other three adsorbents. This is mainly because FDESs-VGO has a more abundant adsorption mechanism (hydrogen bonding, electrostatic adsorption, and π–π stacking) for anti-cancer active substances compared to other adsorbents.

[0046] Example 3

[0047] Using the highly affinity fluorine-functionalized graphene oxide composite material prepared in Example 1 of the present invention as an adsorbent, the filter head dispersive solid-phase extraction technique combined with high-performance liquid chromatography was used to extract and detect the anti-cancer active substances wogonin and chrysin.

[0048] Weigh 15 mg of the highly affinity fluorine-functionalized graphene oxide composite material prepared in Example 1 into a centrifuge tube, add 1 mL of a 5.0 μg / mL mixed standard solution of wogonin and chrysin, after shaking on a shaker for 1 h, filter it with a device assembled by a syringe and a 0.45 μm polytetrafluoroethylene needle filter, and then draw and elute 20 times with 1 mL of methanol, acetonitrile, acetone, DMF, 70% methanol-ammonia water, 70% DMF-ammonia water, and 90% DMF-formic acid respectively. The results are as Figure 6 shown. For the highly affinity fluorine-functionalized graphene oxide composite material prepared in Example 1, when 70% DMF-ammonia water was used as the eluent, the recovery rate of wogonin was 87.0%, and the recovery rate of chrysin was 93.0%, indicating that the highly affinity fluorine-functionalized graphene oxide composite material prepared in Example 1 is suitable for the extraction and separation of wogonin and chrysin.

[0049] Example 4

[0050] Using the FDESs-VGO prepared in Example 1 of the present invention as an adsorbent, the filter head dispersive solid-phase extraction technique combined with high-performance liquid chromatography was used to extract and detect the anti-cancer active substances wogonin and chrysin in Scutellaria baicalensis Georgi from different producing areas.

[0051] The Scutellaria baicalensis Georgi samples from different producing areas were crushed into powders. Weigh 0.5 g of the Scutellaria baicalensis Georgi powder, add it to 20 mL of a 70% anhydrous ethanol-water mixed solution, ultrasonicate for 30 min, then take out the supernatant after high-speed centrifugation of the mixed solution, evaporate the solvent by rotary evaporation and re-dissolve it with 20 mL of 10% DMF-water for storage. Add the highly affinity fluorine-functionalized graphene oxide composite material (15 mg) into a 10 mL centrifuge tube. Subsequently, add 1 mL of the Scutellaria baicalensis Georgi sample solution into the centrifuge tube and ultrasonicate for 3 min, then filter it with a device assembled by a syringe and a 0.45 μm polytetrafluoroethylene needle filter, wash it with 1 mL of 10% methanol-water to remove impurities, and then use 0.8 mL of 70% DMF-ammonia water to draw and elute the target analytes 5 times. The results are as Figure 7 shown. There are significant differences in the amounts of wogonin and chrysin contained in Scutellaria baicalensis Georgi from different producing areas. The results show that the highly affinity fluorine-functionalized graphene oxide composite material prepared in the present invention has good adsorption properties for wogonin and chrysin, and can be used for the extraction and detection of wogonin and chrysin in complex matrix samples.

[0052] Example 5

[0053] Using the FDESs-VGO prepared in Example 1 of the present invention as an adsorbent, centrifugal accelerated tip solid-phase extraction-high performance liquid chromatography was used for the extraction and detection of different fluorinated pesticides in Scutellaria baicalensis Georgi.

[0054] The Scutellaria baicalensis Georgi sample was ground into powder. Weigh 0.5 g of Scutellaria baicalensis Georgi powder and add it to 20 mL of a 70% anhydrous ethanol-water mixed solution, ultrasonicate for 30 min, then take out the supernatant after high-speed centrifugation of the mixed solution, rotary evaporate the solvent and re-dissolve it with 20 mL of 10% DMF-water, and store for later use. Prepare a spiked Scutellaria baicalensis Georgi sample solution containing 5.0 μg / mL of boscalid, pyraclostrobin, and trifloxystrobin. Weigh 5 mg of FDESs-VGO and add it to a self-assembled tip solid-phase extraction column, and then activate the tip solid-phase extraction column with 1 mL of methanol and 1 mL of water respectively. Subsequently, take 1 mL of the above spiked Scutellaria baicalensis Georgi sample solution and add it to the tip extraction column, and use centrifugation to make the solution in the tip flow through the FDESs-VGO material. Finally, elute the target adsorbed on the FDESs-VGO with 1 mL of methanol. After the eluate is dried with nitrogen, it is re-dissolved with 1 mL of mobile phase and detected by HPLC. The results are as Figure 8 shown. The recoveries of FDESs-VGO for boscalid, pyraclostrobin, and trifloxystrobin are all above 85.0%, indicating that FDESs-VGO can be used for the extraction and detection of fluorinated pesticides (boscalid, pyraclostrobin, and trifloxystrobin) in Scutellaria baicalensis Georgi samples.

[0055] Comparative Example 1

[0056] Weigh 200 mg of graphene oxide and ultrasonically disperse it in a mixed solution composed of 80 mL of anhydrous ethanol and 20 mL of purified water. The ultrasonic power is 150 W, the ultrasonic frequency is 45 kHz, and the ultrasonic time is 3 h to obtain a graphene oxide dispersion. Then add vinyltrimethoxysilane (1 mL) to the graphene oxide dispersion, slowly add 10 mL of ammonia water after 10 min, stir at 70.0 °C for 12 h, and then wash with 95% ethanol and purified water respectively and freeze-dry to obtain vinyl-functionalized graphene oxide.

[0057] Synthesize fluorinated deep eutectic solvent: Weigh 1.5 mmol of (3-acrylamidopropyl) trimethylammonium chloride and 3.0 mmol of 2-trifluoromethylacrylic acid and heat and dissolve them in a water bath at 80.0 °C.

[0058] Weigh 100 mg of vinyl-functionalized graphene oxide and add it to 28 mL of DMF. Sonicate for 3 h. Disperse the prepared fluorinated deep eutectic solvent with 1 mL of DMF and add it to the ultrasonically dispersed vinyl graphene oxide dispersion. Then, add 7.5 mmol of N,N'-methylenebisacrylamide and 50 mg of azobisisobutyronitrile in sequence. Under nitrogen protection, react at 70.0 °C and 350 rpm for 24 h. Then, wash with methanol and purified water respectively, and freeze-dry to obtain the fluorine-functionalized graphene oxide composite material.

[0059] Using the fluorine-functionalized graphene oxide composite material as an adsorbent, the filter head dispersive solid-phase extraction technique combined with high-performance liquid chromatography was used to extract and detect the anticancer active substances wogonin and chrysin.

[0060] Weigh 15 mg of the fluorine-functionalized graphene oxide composite material in a centrifuge tube, add 1 mL of a 5.0 μg / mL mixed standard solution of wogonin and chrysin. After shaking in a shaker for 1 h, filter with a syringe and a device assembled with a 0.45 μm polytetrafluoroethylene needle filter, and then pull and wash 20 times with 1 mL of methanol, acetonitrile, acetone, DMF, 70% methanol-ammonia water, 70% DMF-ammonia water, and 90% DMF-formic acid respectively. The results are as Figure 9 shown. When the fluorine-functionalized graphene oxide composite material prepared in Comparative Example 1 was used as an adsorbent, the recovery rates of both anticancer active compounds were less than 50.0%, which was not suitable for the extraction and separation of wogonin and chrysin.

[0061] Comparative Example 2

[0062] Weigh 200 mg of graphene oxide and ultrasonically disperse it in a mixed solution composed of 80 mL of absolute ethanol and 20 mL of purified water. The ultrasonic power is 150 W, the ultrasonic frequency is 45 kHz, and the ultrasonic time is 3 h to obtain a graphene oxide dispersion. Then, add 1 mL of vinyltrimethoxysilane to the graphene oxide dispersion. After 10 min, slowly add 10 mL of ammonia water, stir at 70.0 °C for 12 h, and then wash with 95% ethanol and purified water respectively, and freeze-dry to obtain vinyl-functionalized graphene oxide.

[0063] Synthesize the fluorinated deep eutectic solvent: Weigh 1.5 mmol of N-isopropylacrylamide and 3.0 mmol of 2-trifluoromethylacrylic acid and heat and dissolve them in an 80 °C water bath.

[0064] Weigh 100 mg of vinyl-functionalized graphene oxide and add it to 28 mL of DMF. Sonicate for 3 h. Disperse the prepared fluorinated deep eutectic solvent with 1 mL of DMF and add it to the ultrasonically dispersed vinyl graphene oxide dispersion. Then, add 7.5 mmol of N,N'-methylenebisacrylamide and 50 mg of azobisisobutyronitrile in sequence. Under nitrogen protection, react at 70.0 °C and 350 rpm for 24 h. Then, wash with methanol and purified water respectively, and freeze-dry to obtain the fluorine-functionalized graphene oxide composite material.

[0065] Using this fluorine-functionalized graphene oxide composite material as an adsorbent, the anti-cancer active substances wogonin and chrysin were extracted and detected by the filter head dispersive solid-phase extraction technique combined with high performance liquid chromatography.

[0066] Weigh 15 mg of this fluorine-functionalized graphene oxide composite material into a centrifuge tube, add 1 mL of a 5.0 μg / mL mixed standard solution of wogonin and chrysin, shake on a shaker for 1 h, filter with a syringe and a 0.45 μm polytetrafluoroethylene syringe filter assembly device, and then draw and wash 20 times with 1 mL of methanol, acetonitrile, acetone, DMF, 70% methanol-ammonia water, 70% DMF-ammonia water, and 90% DMF-formic acid respectively. The results are as Figure 10 shown. When the fluorine-functionalized graphene oxide composite material prepared in Comparative Example 2 was used as an adsorbent, the recovery rates of the anti-cancer active compounds were all less than 50.0%, which was not suitable for the extraction and separation of wogonin and chrysin.

Claims

1. A high-affinity fluorine-functionalized graphene oxide composite material, characterized in that, The high-affinity fluorinated graphene oxide composite material is prepared by using vinyl-functionalized graphene oxide as a carrier material, fluorinated deep eutectic solvent as a monomer, and N,N'-methylenebisacrylamide as a cross-linking agent through a free radical polymerization reaction in an N,N-dimethylformamide organic system.

2. The high-affinity fluorine-functionalized graphene oxide composite material according to claim 1, characterized in that, The fluorinated deep eutectic solvent is covalently modified and connected to the surface of vinyl-functionalized graphene oxide.

3. The high-affinity fluorine-functionalized graphene oxide composite material according to claim 1, characterized in that, The fluorinated deep eutectic solvent is 2-fluoro-5-(trifluoromethyl)aniline and 2-(trifluoromethyl)acrylic acid.

4. A preparation method of a high-affinity fluorine-functionalized graphene oxide composite material, characterized in that, It includes the following steps: (1) Disperse graphene oxide in a mixed solution composed of absolute ethanol and purified water, then add vinyltrimethoxysilane, and adjust the solution system to be alkaline. After the reaction is completed, wash and freeze-dry to obtain vinyl-functionalized graphene oxide; (2) Add vinyl-functionalized graphene oxide into an N,N-dimethylformamide solution and ultrasonically disperse it evenly; add the fluorinated deep eutectic solvent, N,N'-methylenebisacrylamide, and azobisisobutyronitrile into the vinyl-functionalized graphene oxide dispersion. After the reaction is completed, wash and freeze-dry to obtain the high-affinity fluorinated graphene oxide composite material.

5. The preparation method of the high-affinity fluorine-functionalized graphene oxide composite material according to claim 4, characterized in that, In step (2), the fluorinated deep eutectic solvent is 2-fluoro-5-(trifluoromethyl)aniline and 2-(trifluoromethyl)acrylic acid, and the molar ratio is 1:

2.

6. The preparation method of the high-affinity fluorine-functionalized graphene oxide composite material according to claim 4, characterized in that, In step (2), the molar ratio of the fluorinated deep eutectic solvent to N,N'-methylenebisacrylamide is 1:5 to 1:

8.

7. The preparation method of the high-affinity fluorine-functionalized graphene oxide composite material according to claim 4, characterized in that The reaction conditions in step (2) are specifically: under nitrogen protection, at 70 °C, reacting for 24 h under the condition of 350 rpm.

8. The preparation method of the high-affinity fluorine-functionalized graphene oxide composite material according to claim 4, characterized in that, The reaction conditions in step (1) are specifically: reacting at 70 °C for 12 h.

9. The preparation method of the high-affinity fluorine-functionalized graphene oxide composite material according to claim 4, characterized in that, In step (1), dispersing graphene oxide in a mixed solution composed of absolute ethanol and purified water specifically means: dispersing graphene oxide in a mixed solution composed of absolute ethanol and purified water by ultrasonic method, with the ultrasonic time being 2 - 3 h, the ultrasonic frequency being 40 - 100 kHz, and the ultrasonic power being 100 - 500 W.

10. The high-affinity fluorinated graphene oxide composite material according to any one of claims 1 to 3 or the high-affinity fluorinated graphene oxide composite material prepared by the method according to any one of claims 4 to 9 is used as an adsorbent for extracting and separating fluorine-containing pesticides and anti-cancer active ingredients in Scutellaria baicalensis.

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