Extraction of functional molecules of solanesol, molecularly imprinted polymers, and preparation methods and applications
By preparing functional molecules containing carbonyl and alkyl chains and combining hydrogen bonds and hydrophobic forces, the problem of low selectivity of solanesol molecular imprinting polymers was solved, and efficient extraction and purification of solanesol was achieved.
Patent Information
- Application Number
- CN202411788456.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-06
- Publication Date
- 2025-09-30
- Estimated Expiration
- 2044-12-06
AI Technical Summary
Existing solanesol molecularly imprinted polymers have weak selectivity for solanesol and cannot achieve high-purity extraction.
Hexadecanol and α-methylacrylic acid were used as reaction raw materials to prepare functional molecules containing carbonyl and alkyl chains. These molecules were then reacted with a carboxyl activator and an acylation catalyst to prepare molecularly imprinted polymers, which achieved efficient and specific recognition of solanesol through hydrogen bonding and hydrophobic forces.
Efficient extraction and purification of solanesol was achieved, with an adsorption capacity of up to 61.65 mg/g, significantly improving the adsorption capacity of molecularly imprinted polymers for solanesol.
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Figure CN119569572B_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of solanesol extraction, and in particular to a functional molecule for extracting solanesol, a molecularly imprinted polymer, and a preparation method and application thereof. Background Art
[0002] Solanesol is a substance with high economic added value found in waste tobacco, with a content of 0.3% to 3.0%. Solanesol itself has antibacterial, anti-inflammatory, cardiovascular, and anti-ulcer properties. It is also an important pharmaceutical intermediate, primarily used in the synthesis of coenzyme Q10 (a heart disease treatment drug), vitamin K2, and the anticancer enhancer SDB. In recent years, international demand for solanesol has rapidly increased by over 10% annually. The domestic market also faces a shortage of solanesol products. However, due to technological limitations, my country primarily produces crude solanesol (15% to 20%), which is exported at a market price of 90,000 to 100,000 yuan per ton. High-quality solanesol (90%) is then imported at a price of 1.2 million yuan per ton.
[0003] Currently, the extraction methods for solanesol include steam distillation, solvent extraction, cationic resin exchange, ultrasound-assisted extraction, microwave-assisted extraction, supercritical CO2 extraction, molecular distillation, distillation extraction, column chromatography, and macroporous adsorption resin separation. However, when used alone or in combination, most of these methods have the problems of large equipment, high energy consumption, low extraction purity, and large solvent consumption. Therefore, there is still a lack of separation and purification technology with high purity and yield for the separation of solanesol from tobacco.
[0004] Molecular imprinting is a new, recently emerging technology for separating and purifying organic substances. It possesses a high degree of selectivity for target molecules and their analogs, enabling selective adsorption of target molecules. However, existing solanesol molecularly imprinted polymers (MIPs) often use acrylic acid as the functional molecule. This results in low selectivity for solanesol, making it difficult to achieve high-purity extraction of solanesol. Summary of the Invention
[0005] The present invention provides a functional molecule for extracting solanesol, a molecularly imprinted polymer, and a preparation method and application thereof, which effectively solves the technical problem that molecularly imprinted polymers prepared with acrylic acid as a functional molecule have poor specific selectivity for solanesol and cannot achieve high-purity extraction of solanesol. At the same time, a spatial molecularly imprinted polymer structure with multiple solanesol recognition sites and a certain hardness is provided.
[0006] The purpose of the present invention is to provide a functional molecule for extracting solanesol, the structural formula of the functional molecule is:
[0007] A second object of the present invention is to provide a method for preparing the functional molecule for extracting solanesol, comprising the following steps: using hexadecanol and α-methacrylic acid as reaction raw materials, adding a carboxyl activator and an acylation catalyst sequentially to dichloromethane, performing an esterification reaction at room temperature, and concentrating and separating to obtain the functional molecule for extracting solanesol.
[0008] As a preferred embodiment, the molar ratio of hexadecanol to α-methacrylic acid is 1:1.2-2.5, the molar ratio of hexadecanol to carboxyl activator is 1:1.5-3.0, and the molar ratio of hexadecanol to acylation catalyst is 1:0.3-0.6.
[0009] The third object of the present invention is to provide a molecularly imprinted polymer prepared using the functional molecule for extracting solanesol as a raw material.
[0010] A fourth object of the present invention is to provide a method for preparing a molecularly imprinted polymer, comprising the following steps: dissolving solanesol, α-methacrylic acid, and a functional molecule for extracting solanesol in a porogen, adding a crosslinking agent and an initiator, and heating the mixture to 50-62° C. to carry out a polymerization reaction to obtain a molecularly imprinted polymer.
[0011] As a preferred embodiment, the molar amount of the functional molecule for extracting solanesol is 4 to 6 times that of solanesol, the molar amount of the functional molecule for extracting solanesol is 3% to 10% of α-methacrylic acid, and the molar amount of the cross-linking agent is 30 to 50 times that of solanesol.
[0012] As a preferred embodiment, the porogen is chloroform or n-hexane.
[0013] As a preferred embodiment, the crosslinking agent is N,N'-methylenebisacrylamide, pentaerythritol triacrylate, 3-(trimethoxysilyl)propyl acrylate, trimethylolpropane trimethacrylate or ethylene glycol dimethacrylate.
[0014] As a preferred embodiment, the initiator is azobisisobutyronitrile (AIBN), potassium persulfate, dimethyl azobisisobutyrate or azobisisoheptanenitrile.
[0015] A fifth object of the present invention is to provide a use of the molecularly imprinted polymer for separating and purifying solanesol from tobacco leaves, specifically comprising: loading the molecularly imprinted polymer onto a column to obtain a molecularly imprinted solid phase extraction column, loading the n-hexane extract of tobacco leaves, adsorbing, and eluting.
[0016] Compared with the prior art, the present invention has the following beneficial effects:
[0017] The present invention designs and prepares a functional molecule containing a carbonyl group and an alkyl chain. A carboxyl group, a hydrogen bond acceptor, is introduced into the design of the functional molecule for extracting solanesol. Simultaneously, a hydrophobic group of the alkyl chain is introduced, thereby increasing the recognition sites between the functional molecule for extracting solanesol and the template molecule solanesol. The functional molecule for extracting solanesol of the present invention achieves efficient and specific recognition of the solanesol molecule through hydrogen bonding and hydrophobic forces.
[0018] Functional molecules for extracting solanesol are applied in the preparation of molecularly imprinted polymers. Taking the equilibrium adsorption capacity of solanesol as an indicator, when the dosage of the functional molecules for extracting solanesol is 5%, chloroform is used as the solvent, 30 times the cross-linking agent, and the cross-linking agent N'N-methylenebisacrylamide is used, the prepared molecularly imprinted polymer has the highest adsorption capacity for solanesol. The prepared molecularly imprinted polymer extraction column is applied to extract solanesol from tobacco leaves, achieving efficient extraction and purification of solanesol, with an adsorption capacity of up to 61.65 mg / g. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] Figure 1 This is the hydrogen spectrum of the functional molecule for extracting solanesol prepared in Example 1 of the present invention.
[0020] Figure 2 This is the mass spectrum of the functional molecule extracted from solanesol prepared in Example 1 of the present invention.
[0021] Figure 3 These are SEM images of the molecularly imprinted polymer prepared in Example 1 of the present invention and the non-molecularly imprinted polymer prepared in the comparative example.
[0022] Figure 4 This is a graph showing the effect of the amount of functional molecules used to extract solanesol on the equilibrium adsorption capacity of solanesol by molecularly imprinted polymers.
[0023] Figure 5 This figure shows the effect of the type of porogen on the equilibrium adsorption amount of solanesol by the molecularly imprinted polymer of the present invention.
[0024] Figure 6 Graph showing the effect of the amount of the cross-linking agent used in the present invention on the equilibrium adsorption amount of solanesol by the molecularly imprinted polymer.
[0025] Figure 7 This figure shows the effect of the cross-linking agent type on the equilibrium adsorption amount of solanesol by the molecularly imprinted polymer of the present invention.
[0026] Figure 8 The elution curves of unadsorbed solanesol are shown when the molecularly imprinted polymer of Example 1 of the present invention and the non-molecularly imprinted polymer of Comparative Example 1 are used as eluents to adsorb solanesol.
[0027] Figure 9The elution curves of solanesol adsorption by the molecularly imprinted polymer of Example 1 of the present invention and the non-molecularly imprinted polymer of Comparative Example 1 are shown using chloroform / methanol as eluents.
[0028] Figure 10 This is a comparison chart of the adsorption amount of solanesol in tobacco leaves by the molecularly imprinted polymer of Example 1 of the present invention and the non-molecularly imprinted polymer of Comparative Example 1. DETAILED DESCRIPTION
[0029] To enable those skilled in the art to better understand and implement the technical solutions of the present invention, the present invention is further described below with reference to specific examples, but the examples are not intended to limit the present invention. The following experimental and detection methods are conventional methods unless otherwise specified; the reagents and raw materials are commercially available unless otherwise specified.
[0030] The present invention addresses the technical problem mentioned in the background art: the functional molecule in existing solanesol molecularly imprinted polymers is mostly acrylic acid, resulting in low selectivity for solanesol and an inability to achieve high-purity extraction of solanesol. To address this technical problem, the present invention provides a functional molecule for extracting solanesol, a molecularly imprinted polymer, and a preparation method and application thereof.
[0031] The technical solution of the present invention is further described below.
[0032] The present invention provides a functional molecule for extracting solanesol, and the structural formula of the functional molecule is:
[0033]
[0034] The method for preparing a functional molecule for extracting solanesol comprises the following steps: using hexadecanol and α-methacrylic acid as reaction raw materials, adding a carboxyl activator and an acylation catalyst sequentially to dichloromethane, performing an esterification reaction at room temperature, and concentrating and separating to obtain the functional molecule for extracting solanesol. The carboxyl activator used in the present invention is 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide, denoted as EDC; and the acylation catalyst used is 4-dimethylaminopyridine, denoted as DMAP.
[0035] The functional molecule for extracting solanesol obtained by the above-mentioned technical solution is a functional molecule containing a carbonyl group and an alkyl chain. A carboxyl group, a hydrogen bond acceptor, is introduced into the design of the functional molecule for extracting solanesol, and a hydrophobic group of the alkyl chain is simultaneously introduced to increase the number of recognition sites between the functional molecule for extracting solanesol and the template molecule. The molecule is simple to synthesize and has a high yield. It can achieve efficient and specific recognition of solanesol molecules through hydrogen bonding and hydrophobic interactions, thereby efficiently separating and extracting solanesol from waste tobacco leaves.
[0036] As a preferred embodiment, the molar ratio of hexadecanol to α-methacrylic acid is 1:1.2-2.5, the molar ratio of hexadecanol to carboxyl activator is 1:1.5-3.0, and the molar ratio of hexadecanol to acylation catalyst is 1:0.3-0.6.
[0037] A molecularly imprinted polymer is prepared using the functional molecule extracted from solanesol as a raw material, comprising the following steps: dissolving solanesol, α-methacrylic acid and the functional molecule extracted from solanesol in a porogen, adding a crosslinking agent and an initiator, and heating to 50-62° C. to carry out polymerization reaction to obtain the molecularly imprinted polymer.
[0038] As a preferred embodiment, the molar amount of the functional molecule for extracting solanesol is 4 to 6 times that of solanesol, the molar amount of the functional molecule for extracting solanesol is 3% to 10% of α-methacrylic acid, and the molar amount of the cross-linking agent is 30 to 50 times that of solanesol.
[0039] It should be noted that the selection and dosage of the functional molecule for extracting solanesol are very important in the preparation of molecularly imprinted polymers. It not only needs to have a structure that can form a recognition site with the template molecule solanesol, but also be able to undergo copolymerization with the cross-linking agent to form a spatial polymer structure with a certain hardness. The present invention first investigated the effect of the dosage of the functional molecule for extracting solanesol on the equilibrium adsorption capacity of the molecularly imprinted polymer using static adsorption experiments. The results are as follows: Figure 4 The results show that when the amount of the solanesol extracting functional molecule is 5%, the molecularly imprinted polymer has the highest adsorption capacity for solanesol molecules, approximately 76.29 mg / g. However, when the amount of the solanesol extracting functional molecule is 33%, the molecularly imprinted polymer has the lowest adsorption capacity for solanesol molecules, only 36.48 mg / g. In summary, when the amount of the solanesol extracting functional molecule is 5%, the molecularly imprinted polymer has the best adsorption effect for solanesol molecules. The reason for the overall increase followed by decrease is that as the amount of the solanesol extracting functional molecule increases, the self-assembly between solanesol and the solanesol extracting functional molecule becomes more complete, forming a stable self-assembled complex, resulting in strong adsorption. However, when the amount of the solanesol extracting functional molecule is too high, the self-assembly between them is destroyed, resulting in poor adsorption performance.
[0040] As a preferred embodiment, the porogen is chloroform or n-hexane.
[0041] It should be noted that porogens are important components in the preparation of molecularly imprinted polymers. In addition to dissolving functional molecules, template molecules such as solanesol, and acting as crosslinkers, porogens can also disperse the heat generated during the polymerization process, producing a pore-forming effect on the material, thereby affecting the polymer's surface morphology, particle uniformity, specific surface area, pores, and rigidity, ultimately affecting the molecularly imprinted polymer's ability to recognize template molecules. The present invention conducts a comparative study on the adsorption properties of molecularly imprinted polymers prepared using commonly used porogens, including acetonitrile, methanol, dichloromethane, chloroform, and n-hexane. Figure 5 As shown. The results show that when the solvent is chloroform, the molecular imprinting polymer has the largest adsorption capacity for solanesol molecules, which is about 119.86 mg / g; while acetonitrile is significantly inferior to the other four solvents, with an adsorption capacity of only 59.70 mg / g. The above results show that different solvent types have a great influence on the adsorption capacity of the molecular imprinting polymer for the target molecule solanesol, among which the adsorption effect is from strong to weak in the order of chloroform > dichloromethane > n-hexane > methanol > acetonitrile. The reason for this phenomenon is related to the polarity of the solution. For example, chloroform, dichloromethane and n-hexane have low polarity, so the effect of producing polymers is better, while solvents with high polarity such as methanol and acetonitrile will weaken the bond between the MIP and the functional molecules for extracting solanesol, resulting in a significant impact on recognition.
[0042] As a preferred embodiment, the crosslinking agent is N,N'-methylenebisacrylamide, pentaerythritol triacrylate, 3-(trimethoxysilyl)propyl acrylate, trimethylolpropane trimethacrylate or ethylene glycol dimethacrylate.
[0043] It should be noted that in the molecular imprinting process, a cross-linking agent is used to fix the template molecule-functional monomer complex to form a polymer with a specific spatial structure for the imprinted molecule. The type of cross-linking agent mainly affects the polymer morphology, changes the accessibility of the pores and the adsorption kinetics. When selecting a cross-linking agent, it is required that the synthesized polymer has a certain rigidity to maintain the shape of the pores, and also has a certain flexibility to make the recognition point have better accessibility, thereby improving its adsorption performance. In the early experimental stage of the present invention, the effects of molecular imprinting polymers prepared with five cross-linking agents (N,N'-methylenebisacrylamide MBA, pentaerythritol triacrylate PETA, trimethylolpropane trimethacrylate TMPTMA, ethylene glycol dimethacrylate EDMA, 3-(trimethoxysilyl)propyl acrylate) on the adsorption performance of solanesol were investigated. Figure 7The results show that different cross-linkers significantly affect the amount of solanesol adsorbed by the molecularly imprinted polymers, but all exhibit good adsorption for the target molecule, solanesol. The order of adsorption performance, from strongest to weakest, is MBA > PETA > 3-(trimethoxysilyl)propyl acrylate > TMPTMA > EDMA. This is because the MBA molecule has two amide groups within it, which form a network during the reaction, resulting in a more stable three-dimensional configuration.
[0044] In addition, the amount of crosslinker used will affect the rigidity of the polymer and the accessibility of the recognition site. When the crosslinker amount is too high, the capacity of the polymer decreases, the rigidity is strong, and the accessibility of its recognition site is poor. On the contrary, when the crosslinker amount is too low, the rigidity is weak, resulting in strong accessibility of its recognition site and reduced specific binding. In the experiment, EDMA (ethylene glycol dimethacrylate) was used as the crosslinker. The effect of different crosslinker amounts (relative to the template molecule solanesol) on the adsorption of solanesol is shown in the figure below. Figure 6 The results show that when the crosslinker dosage is 30 times that of the original, the molecularly imprinted polymer exhibits the best adsorption of solanesol molecules, with an adsorption capacity of 98.60 mg / g. However, when the crosslinker dosage is low, the adsorption performance is significantly weaker than when the crosslinker dosage is high. Generally speaking, the adsorption effect of the molecularly imprinted polymer on the target molecule should be better with increasing the crosslinker dosage, because increasing the crosslinker dosage can make the three-dimensional structure of the interaction site more stable, thereby improving the specific recognition ability of the molecularly imprinted polymer for the target molecule.
[0045] It should be noted that the initiator is azobisisobutyronitrile (AIBN), potassium persulfate, dimethyl azobisisobutyrate or azobisisoheptanenitrile. In the subsequent examples of the present invention, azobisisobutyronitrile is used as the initiator.
[0046] The technical effects of the present invention are described in detail below with reference to specific embodiments and comparative examples.
[0047] The preparation method of the functional molecule for extracting solanesol adopted by the present invention is specifically as follows: hexadecanol (2.42 g, 10.0 mmol), α-methylacrylic acid (1.03 g, 12.0 mmol), EDC (2.87 g, 15.0 mmol), and DMAP (0.37 g, 3.0 mmol) are sequentially added to 25 mL of dichloromethane, reacted at room temperature for 24 hours, and completely consumed the hexadecanol after monitoring by TLC. After completion of the reaction, the reaction solution is concentrated under reduced pressure, and the crude product is separated and purified by using a silica gel column with ethyl acetate-methanol (V / V=5:1) as the mobile phase, to finally obtain the functional molecule for extracting solanesol in a yellow liquid state.
[0048] Example 1
[0049] A method for preparing a molecularly imprinted polymer comprises the following steps:
[0050] According to the molar ratio of solanesol and the functional molecule extracted from solanesol of 1:5, and the molar ratio of α-methacrylic acid and the functional molecule extracted from solanesol of 1:0.05, the template molecule solanesol, α-methacrylic acid and the functional molecule extracted from solanesol were dissolved in a certain amount of porogen, vacuumed and placed at -4°C for 10 minutes. After full reaction, the cross-linker EDMA (30 times the molar amount of solanesol) was added, ultrasonicated for 10 minutes, and finally the initiator AIBN was added. The temperature was raised to 60°C and polymerized for 24 hours. The obtained polymer was crushed and passed through a 200-mesh sieve, first rinsed with a certain amount of acetic acid:methanol (v / v=1:9), and then washed with 500 mL of methanol to obtain a molecularly imprinted polymer, which was recorded as MIP.
[0051] Example 2
[0052] A method for preparing a molecularly imprinted polymer comprises the following steps:
[0053] According to the molar ratio of solanesol and the functional molecule extracted from solanesol of 1:4, and the molar ratio of α-methacrylic acid and the functional molecule extracted from solanesol of 1:0.03, the template molecule solanesol, α-methacrylic acid and the functional molecule extracted from solanesol were dissolved in a certain amount of porogen, vacuumed and placed at -4°C for 10 minutes. After full reaction, the cross-linker EDMA (50 times the molar amount of solanesol) was added, ultrasonicated for 10 minutes, and finally the initiator AIBN was added. The temperature was raised to 60°C and polymerized for 24 hours. The obtained polymer was crushed and passed through a 200-mesh sieve, first rinsed with a certain amount of acetic acid:methanol (v / v=1:9), and then washed with 500 mL of methanol to obtain a molecularly imprinted polymer, which was recorded as MIP.
[0054] Example 3
[0055] A method for preparing a molecularly imprinted polymer comprises the following steps:
[0056] According to the molar ratio of solanesol and the functional molecules extracted from solanesol of 1:6, and the molar ratio of α-methacrylic acid and the functional molecules extracted from solanesol of 1:0.1, the template molecule solanesol, α-methacrylic acid and the functional molecules extracted from solanesol were dissolved in a certain amount of porogen, vacuumed and placed at -4°C for 10 minutes. After full reaction, the cross-linker EDMA (40 times the molar amount of solanesol) was added, ultrasonicated for 10 minutes, and finally the initiator AIBN was added. The temperature was raised to 60°C and polymerized for 24 hours. The resulting polymer was crushed and passed through a 200-mesh sieve, first rinsed with a certain amount of acetic acid:methanol (v / v=1:9), and then washed with 500 mL of methanol to obtain a molecularly imprinted polymer, recorded as MIP.
[0057] Example 4
[0058] A method for preparing a molecularly imprinted polymer comprises the following steps:
[0059] According to the molar ratio of solanesol and the functional molecules extracted from solanesol of 1:4.5, and the molar ratio of α-methacrylic acid and the functional molecules extracted from solanesol of 1:0.05, the template molecule solanesol, α-methacrylic acid and the functional molecules extracted from solanesol were dissolved in a certain amount of porogen, vacuumed and placed at -4°C for 10 minutes. After full reaction, the cross-linker EDMA (35 times the molar amount of solanesol) was added, ultrasonicated for 10 minutes, and finally the initiator AIBN was added. The temperature was raised to 60°C and polymerized for 24 hours. The obtained polymer was crushed and passed through a 200-mesh sieve, first rinsed with a certain amount of acetic acid:methanol (v / v=1:9), and then washed with 500 mL of methanol to obtain a molecularly imprinted polymer, which was recorded as MIP.
[0060] Example 5
[0061] A method for preparing a molecularly imprinted polymer comprises the following steps:
[0062] According to the molar ratio of solanesol and the functional molecule extracted from solanesol of 1:5.5, and the molar ratio of α-methacrylic acid and the functional molecule extracted from solanesol of 1:0.06, the template molecule solanesol, α-methacrylic acid and the functional molecule extracted from solanesol were dissolved in a certain amount of porogen, vacuumed and placed at -4°C for 10 minutes. After full reaction, the cross-linker EDMA (45 times the molar amount of solanesol) was added, ultrasonicated for 10 minutes, and finally the initiator AIBN was added. The temperature was raised to 60°C and polymerized for 24 hours. The obtained polymer was crushed and passed through a 200-mesh sieve, first rinsed with a certain amount of acetic acid:methanol (v / v=1:9), and then washed with 500 mL of methanol to obtain a molecularly imprinted polymer, which was recorded as MIP.
[0063] In order to further illustrate the technical effects of the present invention, the present invention also provides a comparative example, which is as follows:
[0064] Comparative Example 1
[0065] A method for preparing a non-imprinted polymer comprises the following steps:
[0066] According to the molar ratio of α-methacrylic acid and the functional molecule for extracting solanesol of 1:0.05, α-methacrylic acid and the functional molecule were dissolved in a certain amount of porogen, vacuumed and placed at -4°C for 10 minutes. After full reaction, the cross-linker EDMA (30 times the molar amount of solanesol) was added, ultrasonicated for 10 minutes, and finally the initiator AIBN was added. The temperature was raised to 60°C and polymerized for 24 hours. The resulting polymer was crushed and passed through a 200-mesh sieve, first rinsed with a certain amount of acetic acid:methanol (v / v=1:9), and then washed with 500 mL of methanol to obtain a non-imprinted polymer, which was recorded as NIP.
[0067] The molecularly imprinted polymers prepared in Examples 1 to 5 of the present invention and the non-imprinted polymer prepared in Comparative Example 1 were used to separate and purify solanesol from tobacco leaves. The specific performance tests are as follows:
[0068] 1. Characterization of functional molecules extracted from solanesol
[0069] use 1 H NMR and HRMS were used to characterize the structure of the functional molecules of the extracted solanesol. Figure 1 and Figure 2 As shown. Figure 1 and Figure 2 The results show that the prepared substance conforms to the expected chemical structure and has high purity.
[0070] 2. Characterization of molecularly imprinted polymers
[0071] The surface characteristics of the polymer were characterized by SEM, the measurement voltage of the scanning electron microscope was 15 kV, and the sample magnification was 50,000 times. The surface characteristics of the MIP prepared in Example 1 of the present invention and the NIP molecularly imprinted polymer prepared in Comparative Example 1 are as follows: Figure 3 As shown by Figure 3 The results showed that Figure 3 In Figure A, the particle size distribution of MIP molecularly imprinted polymer is relatively uniform, and the smaller the size, the larger the surface area. Figure 3 In Figure B, the surface structure of the NIP molecularly imprinted polymer is relatively loose and the particle size is larger, indicating that the molecularly imprinted polymer with solanesol as the template molecule has a larger surface area to bind to the target molecule.
[0072] 3. Application of molecularly imprinted polymers in tobacco
[0073] The molecularly imprinted polymer prepared in Example 1 was loaded into a molecularly imprinted solid phase extraction column, and the separation and analysis of solanesol in tobacco was performed according to the following process:
[0074] Preparation of functional molecules for extracting solanesol → Preparation and optimization of molecular imprinting polymers → Column loading (molecularly imprinted solid phase extraction column) → Sample loading (n-hexane extract of tobacco leaves) → Elution of unadsorbed solanesol with n-hexane → Elution of adsorbed solanesol with chloroform / methanol → UV recording of elution curve and analysis of the adsorption amount of solanesol.
[0075] Figure 8 The adsorption curve of solanesol when tobacco leaf extract was added to a 5 g molecularly imprinted polymer column showed that almost all the unadsorbed solanesol was eluted when the 10th tube was washed with n-hexane.
[0076] Figure 9The figure shows the elution curve of solanesol when chloroform / methanol is used as the eluent. As can be seen from the figure, for the NIP-SPE column, the solanesol concentration reaches its maximum when eluting to the 4th tube, while for the MIP-SPE column, the solanesol concentration reaches its maximum when eluting to the 8th tube, indicating that the interaction between the MIP molecularly imprinted polymer and solanesol is more effective, resulting in a later elution. Based on the above data, the adsorption capacity of solanesol in waste tobacco leaves by the MIP-SPE column and the NIP-SPE column is calculated to be 37.85 mg / g and 61.65 mg / g, respectively. Figure 10 As shown, it shows that the MIP column can more effectively identify and adsorb solanesol.
[0077] Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such changes and modifications fall within the scope of the claims and their equivalents, the present invention is intended to include such changes and modifications.
Claims
1. A method for preparing a molecularly imprinted polymer, characterized in that: The following steps are involved: Solanesol, α-methacrylic acid and functional molecules extracted from solanesol are dissolved in a porogen, a crosslinking agent and an initiator are added, and the temperature is raised to 50-62°C for polymerization to obtain a molecularly imprinted polymer. The structural formula of the functional molecule for extracting solanesol is: .
2. The preparation method according to claim 1, characterized in that The molar amount of the functional molecule for extracting solanesol is 4 to 6 times that of solanesol, the molar amount of the functional molecule for extracting solanesol is 3% to 10% of α-methacrylic acid, and the molar amount of the cross-linking agent is 30 to 50 times that of solanesol.
3. The preparation method according to claim 1, characterized in that The porogen is chloroform or n-hexane.
4. The preparation method according to claim 1, characterized in that The crosslinking agent is N,N'-methylenebisacrylamide, pentaerythritol triacrylate, 3-(trimethoxysilyl)propyl acrylate, trimethylolpropane trimethacrylate or ethylene glycol dimethacrylate.
5. The preparation method according to claim 1, characterized in that The initiator is azobisisobutyronitrile, potassium persulfate, dimethyl azobisisobutyrate or azobisisoheptanenitrile.
6. A molecularly imprinted polymer, characterized in that The method is prepared according to any one of claims 1 to 5.
7. Use of the molecularly imprinted polymer according to claim 6 in separating and purifying solanesol from tobacco leaves, characterized in that: The molecularly imprinted polymer is loaded into a column to obtain a molecularly imprinted solid phase extraction column, and the n-hexane extract of tobacco leaves is loaded, adsorbed, and eluted.