Pectin-based cryogel particle medium and preparation method thereof
By using pectin as a skeleton and using chemical crosslinking and frozen casting methods and other technologies, pectin-based crystal gel particle media was prepared, which solved the problem of underdeveloped pectin resources and achieved efficient biocompatibility and permeability, and was suitable for high viscosity sample processing and large-scale production.
Patent Information
- Application Number
- CN202510498668.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-18
- Publication Date
- 2025-06-13
AI Technical Summary
The existing pectin processing technology is immature, resulting in underdeveloped pectin resources and waste of resources. At the same time, traditional chromatography columns have difficulties in high viscosity sample processing and large-scale production.
Pectin is used as the framework, and pectin is cross-linked at low temperatures through chemical cross-linking, combined with frozen casting method and airflow cutting and droplet making technology, pectin-based crystal gel particles are prepared.
The pectin-based crystal gel particle medium with excellent biocompatibility, good permeability and high specific surface area was successfully prepared, which solved the problems of traditional chromatography columns in high viscosity sample processing and large-scale production, and achieved efficient utilization of resources.
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Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of porous materials, and particularly relates to a pectin-based cryogel particle medium and a preparation method thereof. Background Art
[0002] As a natural polysaccharide widely present in plant cell walls, pectin has broad application potential in multiple fields due to its good biocompatibility and processability. Xinjiang Uygur Autonomous Region is rich in pectin resources, but the existing pectin processing technologies are not yet mature, resulting in many pectin raw materials still not being fully developed and causing a large amount of resource waste. Therefore, it is particularly urgent to develop biomass materials based on pectin, which has important economic value and environmental protection significance.
[0003] Cryogel is a macroporous material prepared by the freeze-casting method (ice template method). In recent years, it has received extensive attention in chromatographic separation technology due to its excellent pore structure, high porosity, strong mechanical properties, good swelling property, and convective mass transfer ability. The cryogel material based on pectin not only has good biocompatibility and biodegradability, but also its green and environmentally friendly characteristics make it show broad application prospects in multiple industries such as food, medicine, chemical engineering, and biopharmaceuticals.
[0004] Compared with cryogel media of other shapes, the cryogel particle medium has a higher specific surface area and a faster mass transfer rate. In terms of preparation process and cost, the particle medium also has the feasibility of large-scale production and can achieve the consistency of functional modification. By optimizing mass transfer kinetics, improving process adaptability, and expanding application fields, the particle medium effectively solves the problems of traditional chromatography columns in the treatment of high-viscosity samples and large-scale production.
[0005] Based on this, the present invention proposes a preparation method of a pectin-based cryogel particle medium. With pectin as the framework, cross-linking polymerization occurs at low temperature through chemical cross-linking, and by combining the freeze-casting method and an air flow cutting and droplet-forming device, a pectin-based cryogel particle medium is successfully prepared. Summary of the Invention
[0006] The object of the present invention is to provide a preparation method of a pectin-based cryogel particle medium. With pectin as the framework, pectin is cross-linked at low temperature through chemical cross-linking, and by combining the freeze-casting method and the air flow cutting and droplet-forming technology, a pectin-based cryogel particle medium is successfully prepared.
[0007] To achieve the above object, further, the preparation method includes the following steps:
[0008] 1. A preparation method of a pectin-based crystalline hydrogel particle medium, characterized in that the preparation method uses pectin as a framework, crosslinks pectin at low temperature by chemical crosslinking, and successfully prepares a pectin-based crystalline hydrogel particle medium by means of a freeze-casting method and a gas-flow cutting and droplet-forming technique.
[0009] 2. The preparation method according to claim 1, characterized in that the preparation method comprises the following steps:
[0010] (1) Dissolve pectin in ammonia water to carry out the amidation reaction of pectin to obtain a mixed solution 1;
[0011] (2) Dry the mixed solution 1 under the condition of 80 °C to obtain solid amidated pectin;
[0012] (3) Dissolve solid amidated pectin and a crosslinking agent in an aqueous acetic acid solution in sequence, and mix evenly to obtain a mixed solution 2;
[0013] (4) Pump the mixed solution 2 into a gas-flow cutting and droplet-forming device at a certain liquid flow rate. The mixed solution 2 is blown by a certain gas flow rate to obtain droplets. Collect the particles obtained from the droplets with liquid nitrogen. Fish out the particles in the liquid nitrogen and place them in a freezer at -20 °C for 24 - 48 h, and then thaw to obtain a wet pectin-based crystalline hydrogel particle medium;
[0014] (5) Soak the wet crystalline hydrogel with water to remove unreacted substances, and dry to obtain the pectin-based crystalline hydrogel particle medium.
[0015] Further, in the step (1), the pectin content is 3 - 4%.
[0016] Further, in the step (1), the ammonia water concentration is 2 - 4 mol / L; the amidation reaction conditions are at 20 - 40 °C for 1 - 3 h.
[0017] Further, in the step (3), the aqueous acetic acid solution is 1% wt; the crosslinking agent is 50% glutaraldehyde.
[0018] Further, in the step (3), the molar ratio of 50% glutaraldehyde to pectin is 0.1∶1 - 1∶1.
[0019] Further, in the step (4), the liquid flow rate is 0.02 - 0.2 mL / min, and the gas flow rate is 0 - 12 L / min.
[0020] Further, in the step (4), thaw for 5 - 30 min to obtain a wet pectin-based crystalline hydrogel particle medium; in the step (5), replace the deionized water every 1 - 2 h during the soaking treatment, and repeat 5 - 10 times.
[0021] Further, in the step (5), the drying is freeze-drying, the temperature is -80 °C, and the time is 6 to 24 h.
[0022] Further, another object of the present invention is to provide a pectin-based crystalline hydrogel particle medium, which is prepared by the above preparation method, has good molding and has good permeability.
[0023] Further, the particle size of the particles in the pectin-based crystalline hydrogel particle medium is 100 to 1500 μm, and the permeability is 10 -12 ~10 -10 m 2 。
[0024] Compared with the prior art, the beneficial effects of the present invention are as follows:
[0025] 1. The technical solution of the present invention avoids the additional use of an acid solution to remove the excess ammonia water in the pectin amidation process by drying the pectin amidation solution. The obtained solid amidated pectin can be crosslinked and polymerized by a chemical crosslinking agent at low temperature, which is more suitable for the preparation process of crystalline hydrogels compared with the biological crosslinking method; compared with the physical crosslinking method, its structure has higher stability.
[0026] 2. The technical solution of the present invention uses pectin as the backbone to prepare a pectin-based crystalline hydrogel particle medium, which exhibits excellent biocompatibility. By chemically crosslinking pectin, the free carboxyl groups on the pectin molecular chain are retained to the greatest extent, thus constructing a porous separation medium with both biocompatibility and selective adsorption function in one step. Description of the Drawings
[0027] Figure 1 It is a scanning electron microscope picture of the pectin-based crystalline hydrogel particle medium prepared in Example 4 of the present invention.
[0028] Figure 2 It is a scanning electron microscope picture of the pectin-based crystalline hydrogel particle medium prepared in Example 5 of the present invention. Detailed Embodiments
[0029] In order to further illustrate a pectin-based crystalline hydrogel particle medium and its preparation method of the present invention to achieve the intended invention purpose, the following is combined with preferred embodiments, but the protection scope of the present invention is not limited thereto. For a pectin-based crystalline hydrogel particle medium and its preparation method proposed according to the present invention, its specific implementation manners, structures, features and effects are described in detail as follows. In the following description, different "one embodiment" or "embodiment" do not necessarily refer to the same embodiment. In addition, the specific features, structures or characteristics in one or more embodiments can be combined in any suitable form.
[0030] The following will further introduce in detail a pectin-based crystalline hydrogel particle medium and its preparation method according to the present invention in combination with specific embodiments.
[0031] Example 1:
[0032] The specific operation steps are as follows:
[0033] (1) Dissolve pectin in 2 - 4 mol / L ammonia water, and react at 20 - 40 °C for 1 - 3 h to obtain a mixed solution 1 with a mass fraction of 3 - 4%.
[0034] (2) Dry the mixed solution 1 under the condition of 80 °C to obtain solid amidated pectin.
[0035] (3) Dissolve solid amidated pectin and 50% glutaraldehyde in aqueous acetic acid solution in sequence, and mix evenly to obtain a mixed solution 2; the molar ratio of 50% glutaraldehyde to pectin is 0.1∶1 - 1∶1.
[0036] (4) Pump the mixed solution 2 into an air flow cutting droplet-forming device at a liquid flow rate of 0 - 0.2 mL / min. The mixed solution 2 is blown to form droplets by a gas flow rate of 0 - 12 L / min. Collect the droplets with liquid nitrogen to obtain particles. Fish out the particles in liquid nitrogen and place them in a -20 °C freezer for 24 - 48 h, then thaw to obtain a wet pectin-based crystalline hydrogel particle medium.
[0037] (5) Soak the wet crystalline hydrogel with water, change the deionized water every 1 - 2 h, repeat 5 - 10 times. After removing unreacted substances, perform freeze-drying at a temperature of -80 °C for 6 - 24 h to obtain a dry pectin-based crystalline hydrogel particle medium.
[0038] Example 2:
[0039] The specific operation steps are as follows:
[0040] (1) Dissolve 0.6 g of pectin in 20 mL of 2 mol / L ammonia water, and react at 20 °C for 1 h to prepare a mixed solution with a mass fraction of 3%.
[0041] (2) Dry the obtained mixed solution under the condition of 80 °C to obtain solid amidated pectin. Dissolve the obtained solid amidated pectin in 20 mL of acetic acid solution with a mass fraction of 1%, and mix evenly. Ultrasonic for 15 - 30 min to remove air bubbles.
[0042] Drop 0.075 g of 50% glutaraldehyde solution into the amidated pectin solution, and stir for 1 min to mix evenly to obtain a raw material solution.
[0043] (3) Subsequently, a 20 mL disposable syringe was used to suck in the raw material liquid, which was then pumped into the gas flow cutting droplet formation device at a liquid flow rate of 0.2 mL / min, and droplets were obtained by purging with a gas flow rate of 0 L / min. The droplets were collected with liquid nitrogen to obtain particles, and the particles in the liquid nitrogen were fished out and placed in a -20°C freezer for 24 h. The frozen particles were thawed in a room temperature water bath to obtain the pectin-based crystalline gel particle medium.
[0044] (4) The pectin-based crystalline gel particle medium was soaked in deionized water to remove the solvent and unreacted substances, and the deionized water was changed every 1 - 2 h, repeating 5 - 10 times. Finally, it was freeze-dried at -80°C for 12 h to obtain the dry pectin-based crystalline gel particle medium.
[0045] The average particle size of the pectin-based crystalline gel particle medium obtained in Example 2 was 1500 μm, with a rich pore structure and certain mechanical strength, and the permeability was 4.12×10 -10 m 2 。
[0046] Example 3:
[0047] The specific operation steps are as follows:
[0048] (1) 0.8 g of pectin was dissolved in 20 mL of 2 mol / L ammonia water and reacted at 40°C for 3 h to prepare a mixed solution with a mass fraction of 4%.
[0049] (2) The obtained mixed solution was dried at 80°C to obtain solid amidated pectin. The obtained solid amidated pectin was dissolved in 20 mL of acetic acid solution with a mass fraction of 1%, and mixed evenly. Ultrasonic treatment was carried out for 15 - 30 min to remove air bubbles.
[0050] 0.8 g of 50% glutaraldehyde solution was added dropwise to the amidated pectin solution, and stirred for 1 min to mix evenly to obtain the raw material liquid.
[0051] (3) Subsequently, a 20 mL disposable syringe was used to suck in the raw material liquid, which was then pumped into the gas flow cutting droplet formation device at a liquid flow rate of 0.2 mL / min, and droplets were obtained by purging with a gas flow rate of 0 L / min. The droplets were collected with liquid nitrogen to obtain particles, and the particles in the liquid nitrogen were fished out and placed in a -20°C freezer for 24 h. The frozen particles were thawed in a room temperature water bath to obtain the pectin-based crystalline gel particle medium.
[0052] (4) The pectin-based crystalline gel particle medium was soaked in deionized water to remove the solvent and unreacted substances, and the deionized water was changed every 1 - 2 h, repeating 5 - 10 times. Finally, it was freeze-dried at -80°C for 12 h to obtain the dry pectin-based crystalline gel particle medium.
[0053] The average particle size of the pectin-based crystalline hydrogel particles obtained in Example 3 is 1500 μm, which has a rich pore structure and certain mechanical strength, and the permeability is 1.04×10 -10 m 2 。
[0054] Example 4:
[0055] The specific operation steps are as follows:
[0056] (1) Dissolve 0.6 g of pectin in 20 mL of 2 mol / L ammonia water, react at 25 °C for 1 h, and prepare a mixed solution with a mass fraction of 3%.
[0057] (2) Dry the obtained mixed solution at 80 °C to obtain solid amidated pectin. Dissolve the obtained solid amidated pectin in 20 mL of acetic acid solution with a mass fraction of 1%, and mix evenly. Ultrasonic for 15 - 30 min to remove air bubbles.
[0058] Drop 0.26 g of 50% glutaraldehyde solution into the amidated pectin solution, stir for 1 min to mix evenly to obtain the raw material liquid.
[0059] (3) Then suck the raw material liquid with a 20 mL disposable syringe, pump it into the gas cutting droplet formation device at a liquid flow rate of 0.2 mL / min, and blow it with a gas flow rate of 0 L / min to obtain droplets. Collect the droplets with liquid nitrogen to obtain particles, fish out the particles in the liquid nitrogen and place them in a -20 °C freezer for 24 h. Thaw the frozen particles in a room temperature water bath to obtain the pectin-based crystalline hydrogel particle medium.
[0060] (4) Soak the pectin-based crystalline hydrogel particle medium in deionized water to remove the solvent and unreacted substances, change the deionized water every 1 - 2 h, and repeat 5 - 10 times. Finally, freeze-dry at -80 °C for 12 h to obtain the dry pectin-based crystalline hydrogel particle medium.
[0061] The average particle size of the pectin-based crystalline hydrogel particle medium described in Example 4 is 1500 μm. Figure 1 This is the scanning electron microscope picture and particle size distribution diagram of the pectin-based crystalline hydrogel particle medium prepared in Example 4 of the present invention. As Figure 1 can be seen, the prepared product has a rich pore structure, and the average pore diameter is 38 μm.
[0062] Example 5:
[0063] The specific operation steps are as follows:
[0064] (1) Dissolve 0.6 g of pectin in 20 mL of 2 mol / L ammonia water, react at 20 °C for 1 h, and prepare a mixed solution with a mass fraction of 3%.
[0065] (2) The obtained mixed solution was dried at 80 °C to obtain solid amidated pectin. The obtained solid amidated pectin was dissolved in 20 mL of acetic acid solution with a mass fraction of 1%, and mixed evenly. Ultrasonic for 15 - 30 min to remove air bubbles.
[0066] 0.26 g of 50% glutaraldehyde solution was added dropwise to the amidated pectin solution, and stirred for 1 min to mix evenly to obtain the raw material solution.
[0067] (3) Subsequently, 20 mL of disposable syringe was used to suck the raw material solution, and it was pumped into the air flow cutting droplet forming device at a liquid flow rate of 0.2 mL / min, and the droplets were obtained by purging with a gas flow rate of 9 L / min. The droplets were collected with liquid nitrogen to obtain particles, and the particles in liquid nitrogen were fished out and placed in a -20 °C freezer for 24 h. The frozen particles were thawed in a room temperature water bath to obtain the pectin-based crystalline gel particle medium.
[0068] (4) The pectin-based crystalline gel particle medium was soaked in deionized water to remove solvents and unreacted substances, and the deionized water was changed every 1 - 2 h, and repeated 5 - 10 times. Finally, it was freeze-dried at -80 °C for 12 h to obtain the dry pectin-based crystalline gel particle medium.
[0069] The average particle size of the pectin-based crystalline gel particle medium described in Example 5 was 560 μm. Figure 2 This is the scanning electron microscope picture of the pectin-based crystalline gel particle medium prepared in Example 5 of the present invention. As Figure 2 can be seen, the prepared product has a rich pore structure, and the average pore size is 9 μm.
[0070] The above are only the preferred embodiments of the embodiments of the present invention, and do not impose any form of limitation on the embodiments of the present invention. Any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the embodiments of the present invention still fall within the scope of the technical solutions of the embodiments of the present invention.
Claims
1. A method for preparing a pectin-based crystal-gel granular medium, characterized in that: The preparation method uses pectin as a skeleton material, crosslinks and polymerizes at low temperature by chemical crosslinking, and combines freeze casting and airflow cutting drop making technology to successfully prepare a pectin-based crystal gel particle medium.
2. The preparation method according to claim 1, characterized in that: The preparation method comprises the following steps: (1) dissolving pectin in aqueous ammonia to perform an amidation reaction of the pectin to obtain a mixed solution 1; (2) drying the mixed solution 1 at 80° C. to obtain solid amidated pectin; (3) dissolving solid amidated pectin and a cross-linking agent in an acetic acid aqueous solution in sequence and mixing them to obtain a mixed solution 2; (4) The mixed solution 2 is pumped into the airflow cutting droplet making device at a certain liquid flow rate, the mixed solution 2 is purged with a certain gas flow rate to obtain droplets, the particles obtained by the droplets are collected with liquid nitrogen, the particles in the liquid nitrogen are taken out and placed in a -20°C freezer for freezing for 24 to 48 hours, and then thawed to obtain a wet pectin-based crystal gel particle medium; (5) soaking the wet crystal gel in water to remove unreacted substances, and drying to obtain the pectin-based crystal gel particle medium.
3. The preparation method according to claim 1, characterized in that: In the step (1), the pectin content is 3-4%.
4. The preparation method according to claim 1, characterized in that: In the step (1), the concentration of aqueous ammonia is 2-4 mol / L; the amidation reaction conditions are 20-40° C. and the reaction time is 1-3 hours.
5. The preparation method according to claim 1, characterized in that: In the step (3), the acetic acid aqueous solution is 1%wt; and the cross-linking agent is 50% glutaraldehyde.
6. The preparation method according to claim 1, characterized in that: In the step (3), the molar ratio of 50% glutaraldehyde to pectin is 0.1:1 to 1:
1.
7. The preparation method according to claim 1, characterized in that: In the step (4), the liquid flow rate is 0.02 to 0.2 mL / min, and the gas flow rate is 0 to 12 L / min.
8. The preparation method according to claim 1, characterized in that: In the step (4), thawing for 5 to 30 minutes to obtain a wet pectin-based crystal-gel granular medium; In the step (5), the immersion treatment is repeated 5 to 10 times by replacing the deionized water every 1 to 2 hours.
9. The preparation method according to claim 1, characterized in that: In the step (5), the drying is freeze-drying at a temperature of -80°C for 6 to 24 hours.
10. A pectin-based crystal-gel granular medium, characterized in that: The pectin-based crystal-gel particle medium is prepared by the preparation method according to any one of claims 1 to 8.
11. The porous crystal gel according to claim 9, characterized in that: The particle size of the particles in the pectin-based crystal colloid granular medium is 100-1500 μm, and the permeability is 10 -12 ~10 -10 m 2 .