A maggo@pda@pvp composite adsorption material and a preparation method and application thereof

Abstract

The application discloses a kind of magGO@PDA@PVP composite adsorbing material and its preparation method and application, and the composite adsorbing material includes graphene oxide, ferroferric oxide, polydopamine and polyvinylpyrrolidone, in the preparation process, ferroferric oxide and graphene oxide first form composite material, then polydopamine is wrapped in the surface of composite material, finally polyvinylpyrrolidone is grafted on the surface of polydopamine.The application uses the above structure of a kind of magGO@PDA@PVP composite adsorbing material and its preparation method and application, and the prepared magGO@PDA@PVP composite adsorbing material separates polyphenol effective component in traditional Chinese medicinal materials using matrix solid phase dispersion method, solvent usage is less, environmental protection;Compared with traditional ultrasonic extraction method, the polyphenol content extracted is larger, is conducive to subsequent utilization, and simultaneously, the polyphenol extracted can produce good antioxidant property at lower concentration.

Description

Technical Field

[0001] This invention relates to the field of polyphenol extraction technology, and in particular to a magGO@PDA@PVP composite adsorbent material, its preparation method, and its application. Background Technology

[0002] Plant polyphenols are a general term for polyhydroxyphenolic compounds, which are widely found in various plants. They are the most important secondary metabolites in plants and an important direction for new drug development. Plant polyphenols have a variety of physiological activities and pharmacological effects, such as anti-oxidation, anti-cancer, anti-atherosclerosis, antibacterial, and anti-inflammatory effects. They are of great significance for the prevention and treatment of human tumors, aging, and cardiovascular diseases.

[0003] Traditional Chinese medicine contains polyphenols. The extraction of traditional Chinese medicine is a process of extracting the active ingredients from the medicinal materials by selecting an appropriate medium based on the differences in the solubility of various components in different media. At present, the extraction methods of active ingredients are: (1) Solvent extraction method, which uses the principle of like dissolves like to achieve extraction and separation by utilizing the difference in solubility of substances in solvents; (2) Supercritical fluid extraction method, which uses supercritical fluid as an extractant to extract the active ingredients from the target material at a temperature and pressure higher than the critical temperature. When the temperature and pressure are restored to normal, the components dissolved in the fluid are immediately separated from the gaseous fluid in a liquid state dissolved in the absorbent; (3) Microwave extraction method, which uses the difference in the ability of different substances to absorb microwaves to selectively heat certain areas of the matrix material or certain components in the extraction system, so that the extracted material enters the extractant with a smaller dielectric constant and relatively poor microwave absorption ability from the matrix or system, thereby achieving the purpose of extraction.

[0004] Although there are many methods for extracting polyphenols from Chinese medicinal materials, the above methods have the following drawbacks: (1) They use a lot of solvents, which is wasteful and not environmentally friendly; (2) The extraction efficiency is poor and the content of extracted polyphenols is low, which is wasteful of raw materials; (3) The application effect of the extracted effective components is poor and subsequent purification steps are required, which is complicated. Summary of the Invention

[0005] The purpose of this invention is to provide a magGO@PDA@PVP composite adsorbent material, its preparation method, and its application, in order to solve the problems of large solvent usage, low content of extracted polyphenols, and poor application effect of extracted effective components in the above-mentioned process of extracting polyphenols from traditional Chinese medicine.

[0006] To achieve the above objectives, the first aspect of the present invention provides a magGO@PDA@PVP composite adsorbent material, wherein the composite adsorbent material comprises graphene oxide, iron tetroxide, polydopamine and polyvinylpyrrolidone.

[0007] Preferably, iron oxide and graphene oxide first form a composite material, then polydopamine is wrapped around the surface of the composite material, and finally polyvinylpyrrolidone is grafted onto the surface of the polydopamine.

[0008] A second aspect of this invention provides a method for preparing a magGO@PDA@PVP composite adsorbent material, comprising the following steps: (1) Preparation of graphene oxide Graphene oxide was prepared using the Hummers method. (2) Preparation of magGO Graphene oxide was added to an organic solvent and sonicated until completely dissolved. Then sodium citrate, sodium acetate, and ferric chloride hexahydrate were added, and the mixture was sonicated to obtain a homogeneous solution. The solution was then transferred to a reaction vessel for a solvothermal reaction. After magnetic separation, drying, and grinding, magnetic graphene oxide material, namely magGO, was obtained. (3) Preparation of magGO@PDA MagGO was added to a buffer solution and ultrasonically dispersed to obtain a graphene oxide solution. Then, dopamine hydrochloride was added, and the solution was ultrasonically dispersed, stirred, magnetically separated, washed, and dried to obtain polydopamine-encapsulated magnetic graphene oxide, i.e., magGO@PDA. (4) Preparation of magGO@PDA@PVP MagGO@PDA was placed in a PVP solution, and then subjected to ultrasonication, stirring, washing, and drying to obtain a polyvinylpyrrolidone-grafted polydopamine-encapsulated magnetic graphene oxide material, namely magGO@PDA@PVP.

[0009] Preferably, the specific preparation steps of graphene oxide in step (1) are as follows: Graphite powder was slowly added to concentrated H2SO4 and stirred until the graphite powder was evenly dispersed to obtain a mixture. KMnO4 was carefully and slowly added to the mixture and stirred and stored in an ice-water bath for 2 hours. Then, a glass slide was placed over the mouth of the beaker and stirred and heated at 35°C for 2 hours. When the color changed from dark green to brown, 90 mL of ultrapure water was slowly added, the temperature was raised to 95°C, and the reaction was carried out at this temperature for 30 min to obtain the reaction solution. Under stirring conditions, the reaction solution was slowly poured into a beaker containing 280 mL of ultrapure water, and then 30% H2O2 was added dropwise until no obvious bubbles overflowed. The color of the suspension changed from brown to yellow. The reaction solution was left to stand overnight, washed three times with 3% HCl, and then washed seven times with ultrapure water to obtain a pure graphene oxide solution. The solution was ultrasonically dispersed until there was no precipitate, and finally dried to obtain brown flake-like graphene oxide.

[0010] Preferably, the amounts of graphite powder and KMnO4 added are 2.0g and 6.0g, respectively.

[0011] Preferably, the drying temperature in steps (1)-(4) is 50-80°C and the drying time is 24-72h.

[0012] Preferably, the drying temperature in steps (1)-(4) is 50°C and the drying time is 48 hours. Preferably, in step (2), the amounts of graphene oxide, sodium citrate, sodium acetate and ferric chloride hexahydrate added are 0.15g, 0.15g, 1.8g and 0.2g, respectively.

[0013] Preferably, the temperature of the solvothermal reaction in step (2) is 180-220°C and the reaction time is 12-24h.

[0014] Preferably, the temperature of the solvothermal reaction in step (2) is 200°C and the reaction time is 12h.

[0015] Preferably, in step (3), the mass ratio of magGO to dopamine hydrochloride is 1-2:2-4.

[0016] Preferably, in step (3), the mass ratio of magGO to dopamine hydrochloride is 1:2.

[0017] Preferably, in step (4), the mass ratio of magGO@PDA to PVP is 1-2:4-8.

[0018] Preferably, in step (4), the mass ratio of magGO@PDA to PVP is 1:4.

[0019] The third aspect of this invention provides an application of the magGO@PDA@PVP composite adsorbent material, which is used in the extraction process of polyphenols from traditional Chinese medicine.

[0020] The preferred specific process for extracting polyphenols from traditional Chinese medicinal materials is as follows: Weigh out the Chinese medicinal materials and composite adsorbent material and place them in an agate mortar. Mix them evenly and grind them. Then add 70% ethanol aqueous solution, sonicate, elute and magnetically separate to obtain polyphenol extract.

[0021] Preferably, the mass ratio of Chinese medicinal materials to adsorbent material is 1:1.

[0022] Preferably, the Chinese medicinal materials include one of the following: Cistanche deserticola, Saussurea involucrata, and Acanthopanax senticosus.

[0023] Therefore, the magGO@PDA@PVP composite adsorbent material with the above structure, its preparation method, and its application, as described in this invention, have the following beneficial effects: (1) The present invention prepared magGO@PDA@PVP composite adsorbent material, which uses matrix solid phase dispersion method to separate polyphenol effective components in Chinese medicinal materials. The amount of solvent used is small and environmentally friendly.

[0024] (2) Compared with the traditional ultrasonic extraction method, the present invention extracts a larger content of polyphenols, which is beneficial for subsequent use.

[0025] (3) The polyphenols extracted by this invention can produce good antioxidant properties at a low concentration, and the amount of polyphenol drugs used is reduced.

[0026] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0027] Figure 1 This is the infrared spectrum of the composite adsorption material in Example 1; Figure 2 These are SEM images of the composite adsorbent materials in Example 1 (a. graphene oxide, b. magGO, c. magGO@PDA, d. magGO@PDA@PVP). Figure 3 These are graphs showing the polyphenol extraction effects of different adsorption materials on Acanthopanax senticosus. Figure 4 These are graphs showing the effects of different extraction methods on the extraction of polyphenols from Chinese medicinal herbs. Detailed Implementation

[0028] The present invention will be further described below. It should be noted that this embodiment is based on the present technical solution and provides detailed implementation methods and specific operation processes, but the present invention is not limited to this embodiment.

[0029] Example 1 A method for preparing a magGO@PDA@PVP composite adsorbent material includes the following steps: (1) Preparation of graphene oxide (GO) (Hummers method) Slowly pour 46 mL of concentrated sulfuric acid into a 0.5 L beaker and cool it in an ice-water bath. Slowly add 2.0 g of graphite powder to concentrated H2SO4 and stir until the graphite powder is evenly dispersed. Carefully and slowly add 6.0 g of KMnO4 to the mixture and stir and preserve it in an ice-water bath for 2 hours. Then cover the mouth of the beaker with a glass slide and heat it at 35 °C for 2 hours with stirring. When the color changes from dark green to brown, slowly add 90 mL of ultrapure water, raise the temperature to 95 °C, and react at this temperature for 30 min to obtain the reaction solution.

[0030] Under stirring, the reaction solution was slowly poured into a beaker containing 280 mL of ultrapure water. Then, 30% H₂O₂ was added dropwise until no obvious bubbles overflowed and the suspension changed color from brownish-yellow. The reaction solution was allowed to stand overnight. It was washed three times with 3% HCl, and then seven times with ultrapure water to obtain a pure graphene oxide solution. The solution was ultrasonically dispersed at 100 W until no precipitate remained, yielding a graphene oxide solution. Finally, it was dried at 50 °C for 48 h to obtain brownish-yellow sheet-like graphene oxide.

[0031] (2) Preparation of magnetic graphene oxide (magGO) 0.15 g of synthesized graphene oxide was placed in a 100 mL beaker with 40 mL of ethylene glycol and sonicated until completely dissolved. Then, 0.15 g of trisodium citrate, 1.8 g of NaAc, and 0.2 g of FeCl3•6H2O were added, and the mixture was sonicated for 1 h to obtain a homogeneous solution. The homogeneous solution was transferred to a 100 mL sealed high-pressure reactor. The reactor was then heated to 200 °C and maintained for 12 h, followed by natural cooling to room temperature. The product was washed sequentially with anhydrous ethanol and ultrapure water, and then separated using a magnet placed on the outer wall of the tube. Finally, the product was dried in a forced-air environment at 50 °C for 48 h and ground to obtain a black, magnetic graphene oxide material.

[0032] (3) Preparation of polydopamine-encapsulated magnetic graphene oxide (magGO@PDA) 40.0 mg of magnetic graphene was added to 40 mL of Tris buffer (10 Mm, pH=8.5), and then sonicated to disperse it into a homogeneous graphene oxide solution. Next, 80.0 mg of dopamine hydrochloride was added, and the dispersion was sonicated to ensure homogeneity. The mixture was then magnetically stirred at approximately 25°C for 22 h. The magnetic material was separated from the solution using a magnet, and then washed sequentially with anhydrous ethanol and deionized water. The collected final product was dried in an air-dried state at 50°C for 48 h to obtain polydopamine-coated magnetic graphene oxide.

[0033] (4) Preparation of polydopamine-encapsulated magnetic graphene oxide bound to polyvinylpyrrolidone (magGO@PDA@PVP) Prepare 20 mL of an 8.0 g / L PVP solution. Add 40.0 mg of polydopamine-modified magnetic graphene oxide to the prepared PVP solution and sonicate for 1 h. Place the solution on a magnetic stirrer and stir at 30 °C for 24 h. Wash repeatedly with deionized water to remove loosely adsorbed PVP. Dry in a 50 °C forced-air oven to constant weight to obtain the polyvinylpyrrolidone-grafted polydopamine-coated magnetic graphene oxide material.

[0034] Example 2 Polyphenols were extracted from Cistanche deserticola, Saussurea involucrata and Acanthopanax senticosus using a matrix solid-phase dispersion method.

[0035] 10.0 mg of powder from Cistanche deserticola, Saussurea involucrata, and Acanthopanax senticosus were weighed and placed in an agate mortar. The magGO@PDA@PVP material prepared in Example 1 was added at a ratio of 1:1 between the medicinal material sample and the adsorbent. After mixing evenly, the mixture was ground in the agate mortar for 2 min. Then, 4 mL of 70% ethanol aqueous solution was added, and the mixture was eluted by sonication at 250 W for 5 min. An external magnet was used to separate the extract from the material sample mixture, and polyphenol extracts of Cistanche deserticola, Saussurea involucrata, and Acanthopanax senticosus were obtained.

[0036] Experimental Example 1 The composite adsorbent material and its precursor prepared in Example 1 were subjected to FT-IR and SEM tests.

[0037] (1) Infrared spectral characterization To investigate the surface functional groups of the prepared material, infrared spectroscopy characterization was performed. (See attached image.) Figure 1 The infrared spectrum of graphene oxide at 3410 cm⁻¹ -1 The characteristic peaks at this location are -OH peaks, at 1730, 1620, 1401, and 1100 cm⁻¹. -1 The peaks at 570 cm⁻¹ represent the characteristic peaks of C=O, C=C, OC=O, and COC, respectively, indicating the successful synthesis of graphene oxide. In the infrared spectrum of magnetic graphene oxide, the peak at 570 cm⁻¹ is... -1 The absorption peak at 1600 cm⁻¹ corresponds to the Fe-O stretching vibration of Fe₃O₄ particles, indicating the successful formation of magnetic graphene oxide material. After polydopamine encapsulates the magnetic graphene oxide, the absorption peak at 1600 cm⁻¹ in the material spectrum... -1 The peaks at 1358 and 1282 cm⁻¹ are characteristic peaks of the amide group. -1 The positions at 1591 and 1114 cm⁻¹ represent the C=N stretching vibration and CN stretching vibration in the indole ring, respectively, confirming successful PDA encapsulation. (MagnGO@PDA@PVP infrared spectrum, 1591 and 1114 cm⁻¹) -1 The absorption peaks at these locations are characteristic peaks of the C=O and CN stretching vibrations, respectively, indicating that PVP has been successfully adsorbed onto the PDA-encapsulated magnetic graphene oxide. These results demonstrate the successful synthesis of polydopamine-modified magnetic graphene oxide with polyvinylpyrrolidone.

[0038] (2) Scanning electron microscope (SEM) To further observe the surface morphology of the prepared material, scanning electron microscopy was performed. The results are shown in [Figure 1]. Figure 2 .from Figure 2As can be seen, the surface of graphene oxide has slightly layered wrinkles. After synthesizing Fe3O4 on its surface, many spherical small particles appear, indicating that the Fe3O4 particles were successfully synthesized. After coating its surface with polydopamine, Fe3O4 particles can still be observed, but the polydopamine tightly binds them to the surface of graphene oxide. Further coating its surface with polyvinylpyrrolidone (PVP) shows an increase in the material's surface thickness. These results demonstrate the successful synthesis of polydopamine-modified magnetic graphene oxide coated with PPVP.

[0039] Experimental Example 2 (1) Determination of polyphenol content in medicinal materials by the Folin-Ciocalteu method Construction of the gallic acid standard curve: Weigh 0.0010 g of gallic acid standard to prepare a 1.00 mg / mL gallic acid stock solution. Using the gallic acid stock solution, prepare gallic acid working solutions of 10, 20, 30, 40, 50, and 60 μg / mL. Pipette 1 mL of each concentration of working solution into a 10 mL amber volumetric flask, add 1.5 mL of Folin-Ciocalteu reagent, shake well, and let stand for 5 min. Then add 3 mL of 10% Na₂CO₃ solution, and finally add distilled water to make up to volume. Shake well and let stand at room temperature in the dark for 30 min. Measure the absorbance of the gallic acid concentration solutions at 760 nm using a UV spectrophotometer.

[0040] (2) Determination of total polyphenol (TPC) content in medicinal materials Dilute the extracted polyphenol solution 100 times, then pipette 1 mL of the diluted solution into a 10 mL brown volumetric flask, add 1.5 mL of Folin-Ciocalteu reagent, shake well, let stand for 5 min, then add 3 mL of 10% Na₂CO₃ solution, and finally dilute to volume. Incubate in the dark for 1 h, and measure the absorbance at 760 nm. Calculate the total chromatogram (TPC) based on the standard curve. TPC is expressed as mg gallic acid equivalent (GAE) / g dry powder weight (DW).

[0041] (3) Comparison of polyphenol extraction content of different types of adsorption materials.

[0042] Magnetic graphene oxide, polydopamine-modified magnetic graphene oxide, polyvinylpyrrolidone, neutral alumina, and fluorinated silica were selected as adsorbents, respectively, to extract polyphenols from Acanthopanax senticosus under the conditions of Example 2. The extraction effects of different materials on polyphenols from Acanthopanax senticosus were compared. Test results are shown in Table 1 and Table 2. Figure 3 .

[0043]

[0044] As shown in Table 1, the magGO@PDA@PVP material prepared in this invention has significant advantages over commercially available adsorbent materials for the extraction of polyphenols from Acanthopanax senticosus.

[0045] Experimental Example 3 Comparison of polyphenol extraction content using different extraction methods.

[0046] Ultrasonic-assisted extraction of polyphenols from Cistanche deserticola, Saussurea involucrata, and Acanthopanax senticosus: Appropriate amounts of Cistanche deserticola, Saussurea involucrata, and Acanthopanax senticosus powder were weighed and ultrasonically extracted at 250W for 40 min using 70% ethanol at material-to-liquid ratios of 1:25, 1:25, and 1:50, respectively. The extracts were filtered, centrifuged, and the polyphenol extracts from Cistanche deserticola, Saussurea involucrata, and Acanthopanax senticosus were obtained. The test results are shown in Table 2.

[0047]

[0048] From Table 2 and Figure 4 As can be seen, the matrix solid-phase dispersion method of the present invention is significantly better than the ultrasonic extraction method in extracting polyphenols from various medicinal materials. This is because in the prepared magGO@PDA@PVP, the polydopamine-modified magnetic graphene oxide provides a large specific surface area for adsorbing polyvinylpyrrolidone, and the amide bonds on the adsorbed polyvinylpyrrolidone can adsorb the phenolic hydroxyl groups of phenolic compounds, which greatly improves the extraction of polyphenols from medicinal materials.

[0049] Test Example 4 Evaluation of the DPPH free radical scavenging capacity of polyphenol extracts from Cistanche deserticola, Saussurea involucrata and Acanthopanax senticosus.

[0050] (1) Solution preparation Preparation of DPPH solution: Weigh 4 mg of DPPH powder accurately, and dilute to 50 ml in a volumetric flask with anhydrous ethanol. Store in the dark at 4°C.

[0051] Preparation of Vitamin C solution: Weigh out the Vitamin C powder accurately and prepare a 1 mg / ml Vitamin C solution.

[0052] Preparation of sample solutions: Take the polyphenol extracts of Cistanche deserticola, Saussurea involucrata and Acanthopanax senticosus with known polyphenol content, and dilute them into a series of different concentration gradients.

[0053] (2) Experimental methods Blank group A: 100 μL DPPH solution + 100 μL anhydrous ethanol Experimental Group B: 100 μL DPPH solution + 100 μL sample solution Experimental control group C: 100 μL sample solution + 100 μL anhydrous ethanol DPPH solution, sample solution, and anhydrous ethanol were added sequentially to a 96-well plate and mixed thoroughly. The mixture was then incubated at 37°C for 30 min. The absorbance of the sample group was measured at 517 nm using a microplate reader. Using a vitamin C aqueous solution as a positive control, the DPPH scavenging rate was calculated according to the following formula.

[0054] DPPH clearance rate % = ((AC) - (BC)) / (AC) × 100% In the formula, A represents the absorbance of the blank group; B represents the absorbance of the experimental group; and C represents the absorbance of the experimental control group.

[0055] (3) Test results The DPPH free radical scavenging abilities of polyphenol extracts from Acanthopanax senticosus, Saussurea involucrata, and Cistanche deserticola extracted by different methods are shown in Tables 3, 4, and 5, respectively. Among them, the DPPH free radical scavenging ability IC50 of the polyphenol extract from Acanthopanax senticosus obtained by ultrasonic extraction is shown in Tables 3, 4, and 5, respectively. 50 The value was 4.864 μg / ml, and the IC50 value of the DPPH free radical scavenging experiment of the Acanthopanax senticosus polyphenol extract obtained by matrix solid-phase dispersion was 4.864 μg / ml. 50 The value was 3.520 μg / ml; the DPPH free radical scavenging capacity IC of the snow lotus polyphenol extract obtained by ultrasonic extraction was 3.520 μg / ml. 50 The value was 17.271 μg / ml, and the IC50 value of the DPPH free radical scavenging experiment of the snow lotus polyphenol extract obtained by matrix solid-phase dispersion was 17.271 μg / ml. 50 The value was 17.097 μg / ml; the DPPH free radical scavenging capacity IC of the Cistanche deserticola polyphenol extract obtained by ultrasonic extraction was 17.097 μg / ml. 50 The value was 3.203 μg / ml, and the IC50 value of the DPPH free radical scavenging experiment of the Cistanche deserticola polyphenol extract obtained by matrix solid-phase dispersion was 3.203 μg / ml. 50 The value was 2.251 μg / ml.

[0056]

[0057]

[0058]

[0059] Therefore, this invention presents a magGO@PDA@PVP composite adsorbent material with the above-mentioned structure, its preparation method, and its application. The prepared magGO@PDA@PVP composite adsorbent material uses a matrix solid-phase dispersion method to separate the effective polyphenol components in traditional Chinese medicine, which requires less solvent and is environmentally friendly. Compared with the traditional ultrasonic extraction method, the extracted polyphenol content is higher, which is beneficial for subsequent utilization. At the same time, the extracted polyphenols can produce good antioxidant properties at a low concentration.

[0060] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A magGO@PDA@PVP composite adsorbent material, characterized in that: Composite adsorbent materials include graphene oxide, iron oxide, polydopamine, and polyvinylpyrrolidone; The preparation method of the magGO@PDA@PVP composite adsorbent material includes the following steps: (1) Preparation of graphene oxide Graphene oxide was prepared using the Hummers method. (2) Preparation of magGO Graphene oxide was added to an organic solvent and sonicated until completely dissolved. Then sodium citrate, sodium acetate, and ferric chloride hexahydrate were added, and the mixture was sonicated to obtain a homogeneous solution. The solution was then transferred to a reaction vessel for a solvothermal reaction. After magnetic separation, drying, and grinding, magnetic graphene oxide material, namely magGO, was obtained. (3) Preparation of magGO@PDA MagGO was added to a buffer solution and ultrasonically dispersed to obtain a graphene oxide solution. Then, dopamine hydrochloride was added, and the solution was ultrasonically dispersed, stirred, magnetically separated, washed, and dried to obtain polydopamine-encapsulated magnetic graphene oxide, i.e., magGO@PDA. (4) Preparation of magGO@PDA@PVP MagGO@PDA was placed in a PVP solution, and then subjected to ultrasonication, stirring, washing, and drying to obtain a polyvinylpyrrolidone-grafted polydopamine-encapsulated magnetic graphene oxide material, namely magGO@PDA@PVP.

2. The magGO@PDA@PVP composite adsorbent material according to claim 1, characterized in that: The specific preparation steps of graphene oxide in step (1) are as follows: Graphite powder was slowly added to concentrated H2SO4 and stirred until the graphite powder was evenly dispersed to obtain a mixture. KMnO4 was carefully and slowly added to the mixture and stirred and stored in an ice-water bath for 2 hours. Then, a glass slide was placed over the mouth of the beaker and stirred and heated at 35°C for 2 hours. When the color changed from dark green to brown, 90 mL of ultrapure water was slowly added, the temperature was raised to 95°C, and the reaction was carried out at this temperature for 30 min to obtain the reaction solution. Under stirring conditions, the reaction solution was slowly poured into a beaker containing 280 mL of ultrapure water, and then 30% H2O2 was added dropwise until no obvious bubbles overflowed. The color of the suspension changed from brown to yellow. The reaction solution was left to stand overnight, washed three times with 3% HCl, and then washed seven times with ultrapure water to obtain a pure graphene oxide solution. The solution was ultrasonically dispersed until there was no precipitate, and finally dried to obtain brown flake-like graphene oxide.

3. The magGO@PDA@PVP composite adsorbent material according to claim 2, characterized in that: The drying temperature for steps (1)-(4) is 50-80℃ and the drying time is 24-72h.

4. The magGO@PDA@PVP composite adsorbent material according to claim 1, characterized in that: In step (2), the amounts of graphene oxide, sodium citrate, sodium acetate and ferric chloride hexahydrate added are 0.15g, 0.15g, 1.8g and 0.2g, respectively.

5. The magGO@PDA@PVP composite adsorbent material according to claim 1, characterized in that: The temperature of the solvothermal reaction in step (2) is 180-220℃, and the reaction time is 12-24h.

6. The magGO@PDA@PVP composite adsorbent material according to claim 1, characterized in that: In step (3), the mass ratio of magGO to dopamine hydrochloride is 1-2:2-4.

7. The magGO@PDA@PVP composite adsorbent material according to claim 1, characterized in that: In step (4), the mass ratio of magGO@PDA to PVP is 1-2:4-8.

8. The application of the magGO@PDA@PVP composite adsorbent material as described in any one of claims 1 to 7, characterized in that, The magGO@PDA@PVP composite adsorbent material is used in the extraction process of polyphenols from traditional Chinese medicine.

9. The application of the magGO@PDA@PVP composite adsorbent material according to claim 8, characterized in that: The specific process for extracting polyphenols from traditional Chinese medicinal materials is as follows: Weigh out the Chinese medicinal materials and composite adsorbent material and place them in an agate mortar. Mix them evenly and grind them. Then add 70% ethanol aqueous solution, sonicate, elute and magnetically separate to obtain polyphenol extract.

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