Preparation method and application of surface molecularly imprinted polymer adsorbent based on myricetin selective separation
By using deep eutectic solvents and multidimensional matrix materials in a microemulsion system to synthesize surface molecularly imprinted polymers, the problems of high cost and environmental pollution in the separation and purification of myricetin were solved, and efficient and selective separation and enrichment of myricetin were achieved.
Patent Information
- Application Number
- CN202511424753.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-30
- Publication Date
- 2026-01-16
AI Technical Summary
Existing technologies for the separation and purification of myricetin suffer from high costs, resource waste, and environmental pollution, especially the use of traditional organic solvents, which are not environmentally friendly and have low separation efficiency.
Surface molecularly imprinted polymers were synthesized in a microemulsion system using deep eutectic solvent (DES) as the oil phase. Combined with multidimensional matrix materials, the solubility of myricetin was improved through hydrogen bonding and hydrophobic interactions. The particle size of the molecularly imprinted polymers was controlled by adjusting the polarity and morphology of the microemulsion, thus achieving efficient and selective separation.
The prepared adsorbent exhibits strong stability, short adsorption time, strong adsorption capacity for myricetin, good selectivity and regenerability, enabling rapid, efficient and selective separation and enrichment of myricetin, with a maximum adsorption capacity of 102.20 mg/g.
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Figure CN121343067A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the field of material preparation and adsorption separation technology, and particularly relates to a preparation method and application of a surface molecular imprinting polymer adsorbent based on selective separation of myricetin. BACKGROUND
[0002] Myricetin is a naturally occurring plant flavonoid compound, which is widely concerned as a secondary metabolite with important uses in plant roots, stems, leaves and fruits. It is reported that myricetin has antioxidant, anti-inflammatory, antibacterial and anticancer effects. At present, it has been widely used in medicine, food and health care products, and has developed into an important auxiliary drug for treating hypertension, thrombosis and nervous system diseases. Adding myricetin to health care products can play a role in preventing inflammation, protecting the liver and reducing blood sugar. However, the complex flavonoid species and low content of myricetin in plant juice make the separation and purification process of myricetin face the problems of high cost and resource waste caused by complicated separation process. Therefore, it is of great significance to study the green, energy-saving and high-selectivity separation and purification process for the selective separation of myricetin.
[0003] At present, the methods for extracting myricetin from plants mainly include chromatography, liquid-liquid extraction, solid phase extraction and the like. Among them, solid phase extraction is a high-efficiency sample pretreatment technology, which is widely used in the separation and purification of active ingredients of natural products due to its high recovery rate, simple operation, good reproducibility and less solvent consumption. Based on the principle of adsorption separation, this technology is expected to be used for high-efficiency selective separation of myricetin.
[0004] Surface molecular imprinting technology refers to that a template molecule and a functional monomer form a highly cross-linked polymer network under the action of a cross-linking agent and an initiator, a molecularly imprinted polymer microsphere is synthesized on the surface of a matrix material (one-dimensional, two-dimensional, three-dimensional porous material) with a large specific surface area, and then the template molecule is removed by elution, so that "imprinted cavities" matching the molecular shape, size and complementary functional groups of the target molecule are left in the polymer, which can specifically recognize the target molecule through covalent or non-covalent interaction, and can be used for selective separation, enrichment or detection of a specific target. The surface molecularly imprinted polymer (SMIPs) prepared thereby is a kind of high-efficiency separation material with high affinity for the target molecule and specific selective adsorption. However, the use of a large amount of toxic and harmful organic solvents not only causes environmental pollution and resource waste, but also is not conducive to solvent removal and reaction stability. Microemulsion (ME) is a thermodynamically stable and optically transparent homogeneous dispersion liquid formed spontaneously by adding a surfactant to two immiscible water and oil phases, which can provide good solubility and stability for poorly soluble target objects. In recent years, the synthesis of molecularly imprinted polymers in a microemulsion system has been widely studied. The microemulsion method has the advantages of simple operation, low energy consumption, easy control of particle size and morphology, improvement of surface properties and physicochemical properties, and improvement of material stability and uniform distribution. However, the microemulsion also needs to use harmful organic solvents (oil phase), so the deep eutectic solvent (DES) as a new, non-toxic and inexpensive green solvent is expected to be used for the construction of microemulsion to form a special DES type microemulsion. SUMMARY
[0005] The present application provides a preparation method and application of a surface molecularly imprinted polymer adsorbent based on selective separation of myricetin.
[0006] The technical scheme is as follows: S1. Mix a hydrogen bond donor and a hydrogen bond acceptor, heat and stir to obtain a binary hydrophobic deep eutectic solvent; wherein the hydrogen bond acceptor is DL-menthol, and the hydrogen bond donor is any one of acetic acid, propionic acid, n-valeric acid or acrylic acid; S2. Take the binary hydrophobic deep eutectic solvent obtained in S1 as an oil phase, deionized water as a water phase, and add a non-ionic surfactant Tween-80, stir to obtain an oil-in-water microemulsion; S3. Add two-dimensional, three-dimensional, or two-dimensional / three-dimensional composite porous matrix material to the oil-in-water microemulsion described in S2, and ultrasonically disperse it evenly at room temperature. Then add template molecules, 4-vinylpyridine, ethylene glycol dimethacrylate, and azobisisobutyronitrile. After prepolymerization for a period of time, thermally polymerize the product under nitrogen protection. The product is then eluted and dried to obtain a surface molecularly imprinted polymer adsorbent.
[0007] Furthermore, in S3, the template molecule is myricetin, and the amount added is 0.075~0.1 mmol.
[0008] Furthermore, in S1, the molar ratio of the hydrogen bond donor to the hydrogen bond acceptor is 2:1.
[0009] Furthermore, in S1, the specific conditions for heating and stirring are: heating temperature of 70-90 ℃ and stirring time of 1-3 h.
[0010] Furthermore, in S2, the mass ratio of Tween-80 to the binary hydrophobic deep eutectic solvent is 2 to 6.
[0011] Furthermore, in S3, the two-dimensional, three-dimensional, or two-dimensional / three-dimensional composite porous matrix material is any one of double-bond modified MXene, ZIF-67 / MXene composite material, or NH2-UiO-66 / NH2-MIL-125 composite material.
[0012] Furthermore, the amount of the two-dimensional, three-dimensional, or two-dimensional / three-dimensional composite porous matrix material is 10~20 mg.
[0013] Furthermore, in S3, the specific conditions for the thermal polymerization reaction are: polymerization temperature of 50~70 ℃ and polymerization time of 3~4 h.
[0014] Furthermore, in S3, the amount of 4-vinylpyridine added is 0~0.4 mmol.
[0015] On the other hand, the present invention provides the application of a surface molecularly imprinted polymer adsorbent prepared by any of the above methods in the selective adsorption and separation of myricetin.
[0016] Beneficial effects: Compared with the prior art, the specific beneficial effects of this invention are as follows: The application provides a preparation method of a surface molecular imprinting polymer adsorbent based on selective separation of myricetin, which introduces DES as an oil phase into a microemulsion system and uses the DES as a polymerization solvent for synthesis of the molecular imprinting polymer, and simultaneously applies multi-dimensional matrix materials to preparation of the molecular imprinting polymer. Myricetin is a hydrophobic drug, and in the DES type microemulsion, the myricetin can be included in the micelle interior through hydrogen bonding and hydrophilic / hydrophobic interaction, so as to increase the solubility of the poorly soluble target myricetin, and replace the traditional toxic and volatile organic polymerization solvent for preparation of the high-performance surface molecular imprinting polymer. The polarity of the microemulsion can be regulated by changing the composition of the DES and the ratio of the three phases of the microemulsion, so as to accurately control the morphology and particle size of the molecular imprinting polymer microspheres, and further improve the adsorption performance of the molecular imprinting polymer. The use of various two-dimensional, three-dimensional and composite matrix materials provides a larger effective specific surface area, which is beneficial to improving the accessibility of the target molecule and elution of the template molecule, so as to provide more surface active sites, improve the mass transfer efficiency and improve the stability of the molecular imprinting polymer material. The method provided by the application uses various two-dimensional, three-dimensional or composite porous materials as carriers and DES type microemulsion as a polymerization solvent, so that the myricetin can be efficiently and selectively separated, and the preparation method is simple, mild and green.
[0017] The application introduces a functional monomer (such as acrylic acid) capable of acting as a hydrogen bond donor into the DES system, so as to prepare a multifunctional DES type microemulsion, which can be used as a polymerization solvent and a functional monomer simultaneously in the synthesis of the surface molecular imprinting polymer.
[0018] The adsorbent prepared by the application has strong stability, short adsorption time, high adsorption capacity for myricetin, and good selectivity and regeneration.
[0019] The surface molecular imprinting polymer adsorbent prepared by the application can be used for rapid and efficient selective separation and enrichment of myricetin in fruit juice, and the maximum adsorption capacity of the molecular imprinting polymers synthesized by different matrix materials and microemulsions for myricetin can reach 102.20 mg / g. BRIEF DESCRIPTION OF DRAWINGS
[0020] Figure 1 is an FT-IR graph of MXene-D, the surface molecular imprinting polymer adsorbent MMIP-MXene and the non-imprinted polymer MNIP-MXene prepared in Example 1; Figure 2 is an SEM graph of the surface molecular imprinting polymer adsorbent MMIP-MXene prepared in Example 1; Figure 3 is an FT-IR graph of ZIF-67 / MXene, three surface molecular imprinting polymer adsorbents prepared in Example 2; Figure 4 ZIF-67 / MXene, surface molecularly imprinted polymer adsorbent MMIP prepared in Example 2 V - SEM images of ZIF-67 / MXene; Figure 5 FT-IR images of NH2-UiO-66 / NH2-MIL-125, surface molecularly imprinted polymer adsorbent MMIP-NH2-UiO-66 / NH2-MIL-125 (labeled MMIP in the figure), non-imprinted polymer MNIP-NH2-UiO-66 / NH2-MIL-125 (labeled MNIP in the figure) prepared in Example 3; Figure 6 SEM images of surface molecularly imprinted polymer MMIP-NH2-UiO-66 / NH2-MIL-125 prepared in Example 3. DETAILED DESCRIPTION
[0021] The application will be described in detail below in conjunction with the embodiments. Example 1:
[0022] The present embodiment provides a preparation method of a surface molecularly imprinted polymer adsorbent based on selective separation of myricetin, comprising the following steps: (1) The hydrogen bond donor acetic acid and the hydrogen bond acceptor DL-menthol are mixed at a molar ratio of 2:1, and heated and stirred at 80℃ for 2h to obtain a uniform and transparent binary hydrophobic deep eutectic solvent.
[0023] (2) The binary hydrophobic deep eutectic solvent obtained in step (1) is used as the oil phase, deionized water is used as the water phase, and a non-ionic surfactant Tween-80 is added; the Tween-80 and the binary hydrophobic deep eutectic solvent are mixed at a mass ratio of 3, and a certain amount of deionized water is added and stirred to obtain an oil-in-water microemulsion, wherein the three-phase ratio is calculated to be oil phase / surfactant / water phase = 7 / 21 / 72.
[0024] (3) 10 mg of two-dimensional matrix material MXene-D (double bond modified MXene) is added to the oil-in-water microemulsion obtained in step (2), and ultrasonic dispersion is carried out at room temperature until it is uniform, then 0.1 mmol of myricetin, 0.4 mmol of 4-vinylpyridine, 3.0 mmol of ethylene glycol dimethacrylate, and 5 mg of azobisisobutyronitrile are added, and pre-polymerization is carried out for 30 minutes. After being protected by nitrogen, the product is subjected to thermal polymerization reaction at 65 ℃ for 3 h. The product is subjected to Soxhlet extraction elution and drying to obtain a surface molecularly imprinted polymer adsorbent based on selective separation of myricetin. The eluent is a mixture of methanol and acetic acid in a volume ratio of 8:2, and the elution is stopped until there is no ultraviolet-visible light absorption peak at 375 nm in the eluent. The drying temperature is 50 ℃, and the drying time is 6-8 h. The surface molecularly imprinted polymer adsorbent based on selective separation of myricetin prepared in this embodiment is denoted as MMIP-MXene.
[0025] At the same time, a non-imprinted polymer MNIP-MXene is prepared in accordance with the above preparation process, except that no template molecule myricetin is added.
[0026] The structure and morphology of the surface molecularly imprinted polymer adsorbent prepared in this embodiment are comprehensively characterized, and the adsorption conditions are optimized by the control variable method. The adsorption performance is evaluated by adsorption isotherm, adsorption kinetics, selective adsorption and cyclic regeneration experiments. The results show that the MMIP-MXene has a high maximum adsorption capacity (47.43 mg / g), a fast adsorption speed (60 min), a good selectivity (IF=1.56) and an excellent regeneration (still maintaining 87.02% of the adsorption rate after being reused for 5 times).
[0027] The IF is an imprint factor for evaluating the selectivity of the surface molecularly imprinted polymer adsorbent, and the calculation formula of the IF value is:
[0028] Wherein, Q is the equilibrium adsorption capacity.
[0029] The FT-IR graphs of the matrix material MXene-D, the surface molecularly imprinted polymer MMIP-MXene and the non-imprinted polymer MNIP-MXene prepared in this embodiment are shown in Figure 1 From which it can be seen that the MXene-D, MMIP-MXene and MNIP-MXene are successfully synthesized.
[0030] The SEM graph of the surface molecularly imprinted polymer adsorbent MMIP-MXene prepared in this embodiment is shown in Figure 2 From which it can be seen that the molecularly imprinted polymer particle layer is uniformly distributed on the MXene nanosheet. Example 2:
[0031] The present embodiment provides a preparation method of a surface molecularly imprinted polymer adsorbent based on selective separation of myricetin, comprising the following steps: (1) Mix fatty acid acetic acid, propionic acid and n-pentanoic acid with different carbon chain lengths as hydrogen bond donors with hydrogen bond acceptor DL-menthol at a molar ratio of 2:1, heat and stir at 80 ℃ for 2 h to obtain uniform and transparent binary hydrophobic deep eutectic solvents, which are named as DES A , DES P and DES V , respectively.
[0032] (2) Take the three binary hydrophobic deep eutectic solvents DES A , DES P and DES V obtained in step (1) as the oil phase, deionized water as the water phase, and add non-ionic surfactant Tween-80; mix Tween-80 and binary hydrophobic deep eutectic solvents at a mass ratio of 6, and then add a certain amount of deionized water and stir to obtain three oil-in-water microemulsions ME A , ME P and ME V of different polarities, wherein the three-phase ratio is calculated as oil phase / surfactant / water phase = 4 / 24 / 72.
[0033] (3) Add 20 mg of ZIF-67 / MXene composite matrix material to the three oil-in-water microemulsions of different polarities prepared in step (2), ultrasonically disperse uniformly at room temperature, then add 0.1 mmol of myricetin, 0.4 mmol of 4-vinylpyridine, 3.0 mmol of ethylene glycol dimethacrylate, and 5 mg of azobisisobutyronitrile, pre-polymerize for 30 minutes, and then polymerize at 65 ℃ for 3 h under nitrogen protection, and then perform Soxhlet extraction elution and drying to obtain three surface molecularly imprinted polymer adsorbents based on selective separation of myricetin. The eluent is a mixture of methanol and acetic acid at a volume ratio of 8:2, and the elution is stopped until there is no ultraviolet-visible light absorption peak at 375 nm in the eluent; the drying temperature is 50 ℃, and the drying time is 6-8 h. The three surface molecularly imprinted polymer adsorbents based on selective separation of myricetin prepared in the present embodiment are denoted as MMIP A -ZIF-67 / MXene, MMIP P -ZIF-67 / MXene and MMIP V -ZIF-67 / MXene.
[0034] Meanwhile, a non-imprinted polymer MNIP-ZIF-67 / MXene is prepared in the same manner as the preparation process described above except that no template molecule myricetin is added.
[0035] The structure and morphology of the surface molecular imprinting polymer adsorbent prepared in this embodiment are comprehensively characterized, and the adsorption conditions are optimized by the control variable method. The adsorption performance is evaluated through adsorption isotherm, adsorption kinetics, selective adsorption and cyclic regeneration experiments. The results show that the MMIP V -ZIF-67 / MXene has the best adsorption performance, with a maximum adsorption capacity of 75.88 mg / g, a fast adsorption speed (60 min), a good selectivity (IF=1.76) and excellent regeneration (still maintaining 87.50% of the adsorption rate after being reused for 5 times).
[0036] The above IF is an imprinting factor for evaluating the selectivity of the surface molecular imprinting polymer adsorbent. The calculation formula of the IF value is:
[0037] Wherein, Q is the equilibrium adsorption capacity.
[0038] The matrix material ZIF-67 / MXene prepared in this embodiment, the three surface molecular imprinting polymers MMIP A -ZIF-67 / MXene, MMIP P -ZIF-67 / MXene and MMIP V The FT-IR graph of the MMIP Figure 3 -ZIF-67 / MXene is shown in
[0039] The surface molecular imprinting polymer MMIP V -ZIF-67 / MXene prepared in this embodiment is shown in Figure 4 From which it can be seen that the molecular imprinting polymer particles are uniformly distributed on the surface of the ZIF-67 / MXene. Example 3:
[0040] The embodiment provides a preparation method of a surface molecular imprinting polymer adsorbent based on selective separation of myricetin, comprising the following steps: (1) The acrylic acid capable of being used as a functional monomer is mixed with the hydrogen bond acceptor DL-menthol as a hydrogen bond donor at a molar ratio of 2:1, and is subjected to heating and stirring at 80℃ for 2h to obtain a uniform and transparent binary hydrophobic deep eutectic solvent.
[0041] (2) The binary hydrophobic deep eutectic solvent obtained in step (1) is used as the oil phase, deionized water is used as the water phase, and a non-ionic surfactant Tween-80 is added; Tween-80 and the hydrophobic deep eutectic solvent are mixed at a mass ratio of 6, and a certain amount of deionized water is added and stirred to obtain an oil-in-water microemulsion, wherein the three-phase ratio is calculated to be oil phase / surfactant / water phase = 4 / 24 / 72.
[0042] (3) 20 mg of NH2-UiO-66 / NH2-MIL-125 composite matrix material is added to the oil-in-water microemulsion obtained in step (2), and ultrasonic dispersion is performed at room temperature until uniformity is achieved. Then, 0.075 mmol of myricetin, 3.0 mmol of ethylene glycol dimethyl acrylate, and 5 mg of azobisisobutyronitrile are added, and pre-polymerization is performed for 30 minutes. After being protected by nitrogen, the product is subjected to thermal polymerization reaction at 65 ℃ for 3 h. The product is subjected to Soxhlet extraction elution and drying to obtain a surface molecularly imprinted polymer adsorbent based on selective separation of myricetin. The eluent is a mixture of methanol and acetic acid at a volume ratio of 8:2, and the elution is continued until there is no ultraviolet-visible light absorption peak at 375 nm in the eluent. The drying temperature is 50 ℃, and the drying time is 6-8 h. The surface molecularly imprinted polymer adsorbent based on selective separation of myricetin prepared in this example is denoted as MMIP-NH2-UiO-66 / NH2-MIL-125.
[0043] Meanwhile, a non-imprinted polymer MNIP-NH2-UiO-66 / NH2-MIL-125 is prepared in accordance with the above preparation process, except that no template molecule myricetin is added.
[0044] The structure and morphology of the surface molecularly imprinted polymer adsorbent prepared in this example are comprehensively characterized, and the adsorption conditions are optimized by the control variable method. The adsorption performance is evaluated by adsorption isotherm, adsorption kinetics, selective adsorption, and cyclic regeneration experiments. The results show that the maximum adsorption capacity of MMIP-NH2-UiO-66 / NH2-MIL-125 can reach 102.20 mg / g, the adsorption equilibrium time is 50 min, the selectivity is good (IF = 1.48), and the adsorption rate can still reach 82.12% after 5 cycles of recycling.
[0045] The above IF is the imprinting factor, which is used to evaluate the selectivity of the surface molecularly imprinted polymer adsorbent. The calculation formula of the IF value is:
[0046] Wherein, Q is the equilibrium adsorption capacity.
[0047] The FT-IR spectra of the matrix material NH2-UiO-66 / NH2-MIL-125, the surface molecularly imprinted polymer, and the non-imprinted polymer prepared in this example are as follows:Figure 5 The SEM images of the surface molecularly imprinted polymer MMIP-NH2-UiO-66 / NH2-MIL-125 prepared in this example are shown in FIG. 4, from which it can be seen that the successful synthesis of the matrix material and the surface molecularly imprinted polymer.
[0048] The SEM images of the surface molecularly imprinted polymer MMIP-NH2-UiO-66 / NH2-MIL-125 prepared in this example are shown in FIG. 4, from which it can be seen that the successful synthesis of the matrix material and the surface molecularly imprinted polymer. Figure 6 The SEM images of the surface molecularly imprinted polymer MMIP-NH2-UiO-66 / NH2-MIL-125 prepared in this example are shown in FIG. 4, from which it can be seen that the successful synthesis of the matrix material and the surface molecularly imprinted polymer.
[0049] The above embodiments are only for illustrating the technical concepts and characteristics of the present application, and the purpose is to enable those skilled in the art to understand the content of the present application and to implement it, and cannot limit the protection scope of the present application. Any equivalent transformation or modification made according to the spirit and essence of the present application shall be covered within the protection scope of the present application.
Claims
1. A method for preparing a surface molecularly imprinted polymer adsorbent based on the selective separation of myricetin, characterized by, Comprising the following steps: S1. Mix the hydrogen bond donor with the hydrogen bond acceptor, heat and stir to obtain a binary hydrophobic deep eutectic solvent; wherein the hydrogen bond acceptor is DL-menthol, and the hydrogen bond donor is any one of acetic acid, propionic acid, n-valeric acid or acrylic acid; S2. Take the binary hydrophobic deep eutectic solvent obtained in S1 as the oil phase, deionized water as the water phase, and add non-ionic surfactant Tween-80, stir to obtain an oil-in-water microemulsion; S3. Add a two-dimensional, three-dimensional or two-dimensional / three-dimensional composite porous matrix material to the oil-in-water microemulsion described in S2, ultrasonically disperse uniformly at room temperature, then add a template molecule, 4-vinylpyridine, ethylene glycol dimethacrylate and azobisisobutyronitrile, pre-polymerize for a period of time, then heat polymerize under nitrogen protection, and the product is eluted and dried to obtain a surface molecularly imprinted polymer adsorbent.
2. The method for preparing a surface molecularly imprinted polymer adsorbent based on the selective separation of myricetin according to claim 1, characterized in that: In S3, the template molecule is myricetin, and the amount of myricetin added is 0.075-0.1 mmol.
3. The method for preparing a surface molecularly imprinted polymer adsorbent based on the selective separation of myricetin according to claim 1, characterized by: In S1, the molar ratio of the hydrogen bond donor to the hydrogen bond acceptor is 2:
1.
4. The method for preparing a surface molecularly imprinted polymer adsorbent based on the selective separation of myricetin according to claim 1, characterized in that: In S1, the specific conditions of the heating and stirring are as follows: the heating temperature is 70-90 ℃, and the stirring time is 1-3 h.
5. The method for preparing a surface molecularly imprinted polymer adsorbent based on the selective separation of myricetin according to claim 1, characterized by: In S2, the mass ratio of Tween-80 to the binary hydrophobic deep eutectic solvent is 2-6.
6. The method for preparing a surface molecularly imprinted polymer adsorbent based on the selective separation of myricetin according to claim 1, characterized by: In S3, the two-dimensional, three-dimensional or two-dimensional / three-dimensional composite porous matrix material is any one of a double bond modified MXene, a ZIF-67 / MXene composite material or a NH2-UiO-66 / NH2-MIL-125 composite material.
7. The method for preparing a surface molecularly imprinted polymer adsorbent based on the selective separation of myricetin according to claim 6, characterized by: The amount of the two-dimensional, three-dimensional or two-dimensional / three-dimensional composite porous matrix material added is 10-20 mg.
8. The method for preparing a surface molecularly imprinted polymer adsorbent based on the selective separation of myricetin according to claim 1, characterized by: In S3, the specific conditions of the heat polymerization reaction are as follows: the polymerization temperature is 50-70 ℃, and the polymerization time is 3-4 h.
9. The method for preparing a surface molecularly imprinted polymer adsorbent based on the selective separation of myricetin according to claim 1, characterized by: In S3, the amount of 4-vinylpyridine added is 0-0.4 mmol.
10. Use of a surface molecularly imprinted polymer adsorbent prepared by the method of any one of claims 1-9 in the selective adsorption and separation of myricetin.