Rod-like ionic COF, preparation method thereof and application of rod-like ionic COF in separation and purification of active ingredients of cistanche
By preparing rod-shaped ionic COF, the problems of small specific surface area and low adsorption selectivity of existing adsorbents in the separation and purification of ACT in Cistanche deserticola were solved, achieving efficient and simple ACT separation and purification.
Patent Information
- Application Number
- CN202511546288.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-28
- Publication Date
- 2026-02-17
AI Technical Summary
Existing adsorbents for extracting verbascoside (ACT) from Cistanche deserticola suffer from problems such as small specific surface area, fixed pore size distribution, low adsorption selectivity, and complex synthesis process, making it difficult to efficiently separate and purify this active ingredient.
Using the principles of network chemistry and Schiff base reaction, rod-shaped ionic COFs are prepared through a bottom-up self-assembly strategy. 1,3,5-tris(4-formylphenyl)benzene and 1,3-diaminoguanidine hydrochloride are used to form rod-shaped COFs with specific guanidine functional groups. The material surface is rich in active functional groups, has a mesoporous structure and a rough surface, which enhances the binding force with ACT.
The method achieves highly selective and high adsorption capacity separation of ACT, with an adsorption capacity of 245.98 mg/g and a selectivity coefficient of 6.87, which significantly improves the separation and purification efficiency. The material preparation process is simple and the conditions are mild.
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Figure CN121537594A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application belongs to the technical field of covalent organic framework material preparation, natural product separation and purification, and adsorbent preparation, and particularly relates to a rod-like ionic COF, a preparation method thereof, and application of the rod-like ionic COF in separation and purification of active ingredients of Cistanche. BACKGROUND
[0002] Verbascoside (ACT) is a natural product mainly extracted from phenylethanoid glycosides in Cistanche. ACT has strong biological and pharmacological activities. Studies have shown that ACT has a neuroprotective effect and can effectively repair damaged neurons. In addition, ACT also has effects such as anti-atherosclerosis and inhibition of tumor cell growth, which has attracted great interest in the medical, food and health product fields. However, the content of ACT in Cistanche is very low, and obtaining high-purity ACT is a challenge, so it is very important to develop an effective ACT separation and purification method.
[0003] Most active ingredients of natural products are not resistant to high temperature, acid and alkali, which limits the separation method of the active ingredients. The selection of the ACT separation and purification process depends on many factors, including purity, recovery rate and selectivity. Among them, the adsorbent separation method is considered to be one of the most promising ACT separation and purification technologies due to its advantages of high efficiency, easy regeneration, low energy consumption and simple operation. Adsorbents usually work in two ways, physical adsorption and chemical adsorption. Physical adsorption involves intermolecular forces such as van der Waals forces and electrostatic forces, and is usually carried out at low temperature and high pressure; chemical adsorption involves the formation of chemical bonds between the adsorbed molecules and the adsorbent, which requires a certain activation energy, and the adsorption energy is high and the adsorption process is relatively permanent. Common adsorbents include activated carbon, molecular sieves, silica gel, activated alumina, etc., which have large specific surface area, suitable pore structure and surface structure. However, the specific surface area of the above-mentioned methods is relatively small, the pore size distribution and structure are relatively fixed, the adsorption selectivity is not very high, the adsorption limitation is strong, and the synthesis process is relatively complex.
[0004] Therefore, it is necessary to develop an adsorbent with larger specific surface area, adjustable pore distribution and structure, high adsorption selectivity, and simple synthesis process as an adsorption material for ACT. SUMMARY
[0005] In view of the deficiencies in the prior art, the application provides a rod-shaped ionic COF, a preparation method thereof and application thereof in separation and purification of active ingredients of Cistanche; based on the reticular chemistry principle and Schiff base reaction, 1,3,5-tri(4-formylphenyl) benzene TF and 1,3-diamino guanidine hydrochloride DGCl are formed into the rod-shaped ionic COF with specific guanidine functional groups through a self-assembly strategy from bottom to top; the rod-shaped ionic COF has simple preparation process, controllable reaction and mild conditions; and the rod-shaped ionic COF can be used as an adsorption material for separation and purification and has good application in separation and purification of the active ingredient of Cistanche, i.e., verbascoside.
[0006] In order to achieve the above technical effects, the application adopts the following technical means: The application first provides a preparation method of a rod-shaped ionic COF material, comprising the following steps: 1,3,5-tri(4-formylphenyl) benzene, 1,3-diamino guanidine hydrochloride and a solvent are mixed, and the obtained mixed solution is ultrasonically treated to obtain a suspension; The suspension is frozen in a liquid nitrogen bath, then pumped and degassed for circulation, and then sealed, followed by sealed standing in an air-drying oven at a certain temperature, washing and drying to obtain the rod-shaped ionic COF material.
[0007] Preferably, the use amount ratio of 1,3,5-tri(4-formylphenyl) benzene to 1,3-diamino guanidine hydrochloride is 0.01-0.4 mmol: 0.01-0.4 mmol.
[0008] Preferably, the solvent comprises a mixed solution of 1,4-dioxane and water; in the mixed solution, the volume ratio of 1,4-dioxane to water is 4.0 mL: 1.2 mL.
[0009] Preferably, the ultrasonic treatment time is 5-20 min.
[0010] Preferably, the pump degassing time is 1-10 min.
[0011] Preferably, the air-drying oven condition at a certain temperature is sealed standing at 70-200 DEG C for 10-96 h.
[0012] Preferably, the drying condition is standing at 50-100 DEG C for 5-24 h.
[0013] The application further provides the rod-shaped ionic COF material prepared by the above method; the rod-shaped ionic COF material is rich in active functional groups, such as guanidine groups, imine bonds and amino groups, on the surface; and the rod-shaped ionic COF material has a rod-shaped structure, a rough surface and a mesoporous structure.
[0014] The application further provides application of the rod-like ionic COF material in adsorbents.
[0015] Preferably, the application comprises separation and purification of active ingredients of Cistanche.
[0016] Preferably, the active ingredient is verbascoside.
[0017] Compared with the prior art, the application has the following beneficial effects: (1) Based on the reticular chemistry principle and Schiff base reaction, the rod-like ionic COF with specific guanidinium functional groups is formed by self-assembly strategy from bottom to top by reacting 1,3,5-tris(4-formylphenyl) benzene and 1,3-diaminoguanidine hydrochloride; the COF material has high specific surface area, adjustable pore size distribution and ordered pore structure, thereby significantly improving the adsorption selectivity of the material to target molecules; the preparation method of the rod-like ionic COF is simple in operation, mild in conditions and controllable in reaction. During the preparation process of the rod-like ionic COF, the morphology and physical properties thereof are affected by ligands, different ligands form different morphological structures, thereby affecting the transmission path of ACT and the number of adsorption sites; only when 1,3,5-tris(4-formylphenyl) benzene and 1,3-diaminoguanidine hydrochloride react, the rod-like structure of the application can be formed; meanwhile, Cl⁻ in the ionic COF exchanges with the phenolic oxygen ion of ACT, directly occupies the position of Cl⁻, and forms a wide hydrogen bond network with the protonated guanidinium and imine bond.
[0018] (2) The rod-like ionic COF material obtained in the application is rich in active functional groups such as guanidinium, imine bond and amino group on the surface, and has ionic characteristics, can have strong nucleophilic action and electrostatic interaction with verbascoside (ACT) molecules, effectively enhance the binding force between the material and ACT, and thus realize high selective recognition and capture of ACT.
[0019] (3) The rod-like ionic COF material has a typical mesoporous structure and rough surface morphology on the surface, which provides rich mass transfer paths and effective contact interfaces for the material as an adsorbent, and further promotes the adsorption kinetics process and adsorption capacity of ACT. Experimental results show that the maximum adsorption capacity of the rod-like ionic COF material to ACT is 245.98 ± 6.43 mg / g, and the maximum selectivity coefficient is 6.87 ± 0.21, which shows excellent separation performance. In summary, the material has good application potential and industrialization prospect in the separation and purification of active ingredients of natural products, especially phenylethanoid glycosides from Cistanche. BRIEF DESCRIPTION OF DRAWINGS
[0020] Figure 1is a scanning electron microscope image of the rod-like ionic COF prepared in Example 1 (the scale is 500 nm).
[0021] Figure 2 is a transmission electron microscope image of the rod-like ionic COF prepared in Example 1 (the scale is 1 um).
[0022] Figure 3 is a scanning electron microscope image of the spherical ionic COF prepared in Comparative Example 1 (the scale is 500 nm).
[0023] Figure 4 is a transmission electron microscope image of the spherical ionic COF prepared in Comparative Example 1 (the scale is 1 um). DETAILED DESCRIPTION
[0024] The application will be further described below in conjunction with the accompanying drawings and specific examples, but the scope of protection of the application is not limited thereto. The experimental methods not specified in the examples are all according to the conventional conditions; the reagents and materials used, if not specifically stated, can be obtained from commercial channels.
[0025] Example 1: 0.2 mmol of 1,3,5-tris(4-formylphenyl)benzene and 0.2 mmol of 1,3-diaminoguanidine hydrochloride were added into a 25 mL solvent storage bottle, then 4 mL of 1,4-dioxane and 1.2 mL of water were added thereto to obtain solution A; solution A was treated by ultrasonic for 5 min at room temperature to obtain suspension B.
[0026] The solvent storage bottle containing suspension B was frozen in a liquid nitrogen bath, and after three cycles of pumping and degassing for 5 min, it was sealed; the solvent storage bottle was placed in a 120℃ air drying oven and sealed for 72 h, and then washed by centrifugation with N,N-dimethylacetamide, water and acetone for three times, and then dried in a 80℃ vacuum drying oven for 12 h to obtain the rod-like ionic COF.
[0027] The scanning electron microscope image of the rod-like ionic COF material is shown in Figure 1 The transmission electron microscope image is shown in Figure 2 It can be seen from Figure 1 that the rod-like ionic COF presents a rod-like morphology with rough surface, and from Figure 2 that the rod-like ionic COF presents a rod-like morphology.
[0028] The rod-like ionic COF prepared in this example was also tested for performance, and the testing steps were as follows: The prepared rod-like ionic COF was used for ACT / ECH adsorption selectivity test; then a mixed solution of ACT with a concentration of 0.5 mg / mL and ECH with a concentration of 0.5 mg / mL was prepared in a conical flask, 10 mg of the rod-like ionic COF material was added, and the conical flask was placed in a shaking bed (150 rpm) for adsorption for 24 h, and then the sample was taken and the amount of solute in the solution was measured by high performance liquid chromatography.
[0029] The test results show that the adsorption amount of ACT is 245.98 mg / g, and the selectivity is 6.87.
[0030] Example 2: 0.1 mmol of 1,3,5-tris(4-formylphenyl)benzene and 0.1 mmol of 1,3-diaminoguanidine hydrochloride were added to a 25 mL solvent storage bottle, then 2 mL of 1,4-dioxane and 0.6 mL of water were added to obtain solution A; then solution A was treated by ultrasonic treatment at room temperature for 10 min to obtain suspension B.
[0031] The suspension B was frozen in a liquid nitrogen bath, and after three cycles of pumping and degassing for 5 min, it was sealed; then it was placed in a 120°C air-drying oven and sealed for 72 h, and then washed with N,N-dimethylacetamide, water, and acetone three times and dried in a 80°C vacuum drying oven for 12 h to obtain the rod-like ionic COF.
[0032] The prepared rod-like ionic COF was also subjected to performance test, and the test steps were as follows: The prepared rod-like ionic COF was used for ACT / ECH adsorption selectivity test; then a mixed solution of ACT with a concentration of 0.5 mg / mL and ECH with a concentration of 0.5 mg / mL was prepared in a conical flask, 10 mg of the rod-like ionic COF material was added, and the conical flask was placed in a shaking bed (150 rpm) for adsorption for 24 h, and then the sample was taken and the amount of solute in the solution was measured by high performance liquid chromatography.
[0033] The test results show that the adsorption amount of ACT is 217.56 mg / g, and the selectivity is 4.89.
[0034] Example 3: 0.2 mmol of 1,3,5-tris(4-formylphenyl)benzene and 0.3 mmol of 1,3-diaminoguanidine hydrochloride were added to a 25 mL solvent storage bottle, then 4 mL of 1,4-dioxane and 1.2 mL of water were added to obtain solution A; solution A was treated by ultrasonic treatment at room temperature for 10 min to obtain suspension B.
[0035] The solvent storage bottle containing the suspension B was frozen in a liquid nitrogen bath, sealed after three cycles of 5 min pumping and degassing, and then placed in a 120°C blast drying oven for sealed standing for 72 h. After centrifugal washing three times with N,N-dimethylacetamide, water and acetone, the solvent storage bottle was dried in a 80°C vacuum drying oven for 12 h to obtain the rod-like ionic COF.
[0036] The rod-like ionic COF prepared in the example was also subjected to performance testing, and the testing steps were as follows: The rod-like ionic COF prepared in the example was used for ACT / ECH adsorption selectivity testing. A mixed solution of ACT at a concentration of 0.5 mg / mL and ECH at a concentration of 0.5 mg / mL was prepared in a conical flask, and 10 mg of the rod-like ionic COF material was added. The conical flask was placed in a shaking bed (150 rpm) for adsorption for 24 h, and then the amount of solute in the solution was measured by high performance liquid chromatography.
[0037] The test results showed that the adsorption amount of ACT was 242.56 mg / g, and the selectivity was 5.76.
[0038] Comparative Example 1 0.2 mmol of 1,3,5-tris(4-formylphenyl)benzene and 0.2 mmol of triaminoguanidine hydrochloride were added to a 25 mL solvent storage bottle, and then 4 mL of 1,4-dioxane and 1.2 mL of water were added to obtain solution A. Solution A was treated by ultrasonic for 10 min at room temperature to obtain suspension B. The solvent storage bottle containing the suspension B was frozen in a liquid nitrogen bath, sealed after three cycles of 5 min pumping and degassing, and then placed in a 120°C blast drying oven for sealed standing for 72 h. After centrifugal washing three times with N,N-dimethylacetamide, water and acetone, the solvent storage bottle was dried in a 80°C vacuum drying oven for 12 h to obtain the rod-like ionic COF.
[0039] The scanning electron microscope image of the spherical ionic COF material is shown in Figure 3 The transmission electron microscope image is shown in Figure 4 Figure 3 It can be seen that the spherical ionic COF has a rough surface and a spherical morphology. Figure 4 It can be seen that the spherical ionic COF has a solid spherical morphology.
[0040] The spherical ionic COF prepared in the example was also subjected to performance testing, and the testing steps were as follows: The prepared spherical ionic COF was used for ACT / ECH adsorption selectivity testing. A mixed solution of ACT and ECH with a concentration of 0.5 mg / mL and 0.5 mg / mL was prepared in an Erlenmeyer flask, and 10 mg of spherical ionic COF material was added. The mixture was placed in a shaker (150 rpm) for adsorption for 24 h. After that, the amount of solute in the solution was measured by high performance liquid chromatography.
[0041] Test results showed that its ACT adsorption capacity was 161.94 mg / g and the selectivity was 4.03.
[0042] In summary, this invention, based on the principles of network chemistry and the Schiff base reaction, forms a rod-shaped ionic COF with specific guanidine functional groups by assembling 1,3,5-tris(4-formylphenyl)benzene and 1,3-diaminoguanidine hydrochloride through a bottom-up self-assembly strategy. The morphology and physical properties of the rod-shaped ionic COF are influenced by different ligands, resulting in different morphological structures that affect the transport pathway and the number of adsorption sites for ACT. Simultaneously, Cl⁻ in the ionic COF exchanges with the phenolic ions of ACT, directly occupying the Cl⁻ position and forming a broad hydrogen bond network with the protonated guanidine group and imine bond. The preparation process of the rod-shaped ionic COF is simple, the reaction is controllable, and the conditions are mild. The rod-shaped ionic COF can be used as an adsorbent for separation and purification, and has excellent applications in the separation and purification of verbascoside, an active ingredient in Cistanche deserticola.
[0043] The embodiments described above are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments. Any obvious improvements, substitutions or modifications that can be made by those skilled in the art without departing from the essence of the present invention shall fall within the protection scope of the present invention.
Claims
1. A method for preparing a rod-shaped ionic COF material, characterized in that, include: 1,3,5-tris(4-formylphenyl)benzene, 1,3-diaminoguanidine hydrochloride and solvent were mixed, and the resulting mixture was sonicated to obtain a suspension. The suspension was frozen in a liquid nitrogen bath, then the gas was pumped out and circulated, and then sealed. Next, it was sealed and left to stand in a forced-air drying oven at a certain temperature, washed, and dried to obtain the rod-shaped ionic COF material.
2. The method for preparing rod-shaped ionic COF material according to claim 1, characterized in that, The ratio of the amounts of 1,3,5-tris(4-formylphenyl)benzene to 1,3-diaminoguanidine hydrochloride is 0.01~0.4 mmol: 0.01~0.4 mmol.
3. The method for preparing rod-shaped ionic COF material according to claim 1, characterized in that, The solvent comprises a mixture of 1,4-dioxane and water; wherein the volume ratio of 1,4-dioxane to water in the mixture is 4.0 mL:1.2 mL.
4. The method for preparing rod-shaped ionic COF material according to claim 1, characterized in that, The ultrasonic treatment time is 5~20 min; the pump degassing time is 1~10 min.
5. The method for preparing rod-shaped ionic COF material according to claim 1, characterized in that, The conditions for the forced-air drying oven at a certain temperature are: sealed and left to stand for 10 to 96 hours at 70~200℃.
6. The method for preparing rod-shaped ionic COF material according to claim 1, characterized in that, The drying conditions are: standing at 50~100℃ for 5~24 h.
7. The rod-shaped ionic COF material prepared by the method according to any one of claims 1 to 6, characterized in that, The surface of the rod-shaped ionic COF material is rich in active functional groups such as guanidine groups, imine bonds, and amino groups; the rod-shaped ionic COF material exhibits a rod-shaped structure, with a rough surface and a mesoporous structure.
8. The application of the rod-shaped ionic COF material according to claim 7 as an adsorbent.
9. The application according to claim 8, characterized in that, The applications include: separating and purifying the active ingredients of Cistanche deserticola.
10. The application according to claim 9, characterized in that, The active ingredient is verbascoside.