Magnetic gel microsphere of ulva polysaccharide

Abstract

The invention discloses a magnetic gel microsphere of ulva polysaccharide, and belongs to the technical field of magnetic gel microspheres, Fe3O4 magnetic particles and ulva polysaccharide are compounded, the prepared gel microsphere can complete directional movement within 1 minute under the action of an external magnetic field, rapid separation, positioning or control of materials can be conveniently achieved, and the magnetic gel microsphere has a good application prospect. The method has potential application value in the fields of biomedicine, environmental governance and the like.

Description

Technical Field

[0001] The invention relates to a magnetic gel microsphere, in particular to a magnetic gel microsphere of ulva polysaccharide, and belongs to the technical field of magnetic gel microspheres. Background Art

[0002] At present, research on ULP gel mainly focuses on the optimization of its formation mechanism and physical and chemical properties, while the exploration of its practical application is still in its preliminary stage. In-depth exploration of the preparation process, structure-performance relationship and application scenarios of ULP gel will not only help to improve the utilization value of Ulva resources, but also provide theoretical and technical support for the development of new bio-based materials. To this end, a magnetic gel microsphere of Ulva polysaccharide was designed to solve the above problems. Summary of the Invention

[0003] The main purpose of the present invention is to provide a magnetic gel microsphere of ulva polysaccharide.

[0004] The purpose of the present invention can be achieved by adopting the following technical solutions:

[0005] The invention discloses magnetic gel microspheres of ulva polysaccharide, which are composited by ulva polysaccharide and magnetic particles and have a three-dimensional porous network structure. The magnetic particles are uniformly dispersed in the ulva polysaccharide matrix, and the average diameter of the microspheres is 2.0±0.02 mm.

[0006] Preferably, the magnetic particles are Fe3O4 magnetic particles, which can be rapidly aggregated under the action of a magnet.

[0007] Preferably, the purity of the Ulva polysaccharide is greater than 90%.

[0008] Preferably, the microspheres can complete directional movement within 1 minute under the action of an external magnetic field.

[0009] Preferably, the raw materials for preparing the microspheres include FeCl3·6H2O, FeSO4·7H2O, graphene oxide solution, ammonium hydroxide, Ulva green algae, Sevag reagent, and ferric chloride solution.

[0010] Preferably, the concentrations of FeCl3·6H2O and FeSO4·7H2O in ultrapure water are both 0.01 mol.

[0011] Preferably, the Sevag reagent is a mixture of n-butanol and chloroform in a volume ratio of 1:4.

[0012] Preferably, the concentration of the ferric chloride solution is 0.1M.

[0013] Preferably, the method for preparing the microspheres comprises the following steps:

[0014] Dissolve FeCl3·6H2O and FeSO4·7H2O in ultrapure water, stir in ultrapure water at 50°C under N2 protection, add graphene oxide solution and then drop ammonium hydroxide to react, heat to mature, filter and wash until neutral, dry and dissolve in ultrapure water;

[0015] The green algae Ulva was crushed, defatted and dried, crude polysaccharides were extracted by hot water extraction and freeze-dried, dissolved in water and repeatedly treated with Sevag reagent, dialyzed and freeze-dried;

[0016] The ulva polysaccharide is dissolved in a magnetic particle solution, heated in a water bath, injected with a ferric chloride solution, immersed in alcoholization, and freeze-dried to obtain microspheres.

[0017] Beneficial technical effects of the present invention:

[0018] The present invention provides a magnetic gel microsphere of Ulva polysaccharide. By compounding Fe3O4 magnetic particles with Ulva polysaccharide, the prepared gel microspheres can complete directional movement within 1 minute under the action of an external magnetic field, facilitating the rapid separation, positioning or manipulation of materials, and have potential application value in the fields of biomedicine, environmental governance, etc.

[0019] It has a typical interconnected three-dimensional porous network structure, which gives the material a higher specific surface area and porosity, which is conducive to the loading and sustained release of nutrients, drugs or other functional molecules, and can be used as a good carrier material.

[0020] The internal structure of the microspheres is evenly distributed, and the Fe3O4 magnetic particles are evenly dispersed in the network structure of the Ulva polysaccharide matrix without obvious agglomeration, ensuring the stability and consistency of the material performance.

[0021] The prepared Ulva polysaccharide magnetic gel microspheres have an average diameter of about 2.0±0.02 mm and a relatively uniform size distribution, which is conducive to standardized operation and performance regulation in practical applications.

[0022] A specific preparation method is adopted, including the preparation of Fe3O4 magnetic particles, the extraction and purification of Ulva polysaccharide and the composite of the two. The process steps are clear and the repeatability is strong.

[0023] During the preparation process, Fe 3+ It forms a coordination cross-linking effect with the Ulva polysaccharide chain, transforming the conformation of the polysaccharide chain from a loose spiral to a compact aggregation state, thereby enhancing the structural stability and mechanical properties of the gel microspheres. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 forming an image of magnetic particles according to a preferred embodiment of the magnetic gel microspheres of Ulva polysaccharide of the present invention;

[0025] Figure 2This is an image representation of the ulva polysaccharide magnetic gel microspheres according to a preferred embodiment of the ulva polysaccharide magnetic gel microspheres of the present invention;

[0026] Figure 3 This is a microscope image characterization diagram of the ulva polysaccharide magnetic gel microspheres according to a preferred embodiment of the ulva polysaccharide magnetic gel microspheres of the present invention;

[0027] Figure 4 This is an electron microscope analysis diagram of the internal structure of the ulva polysaccharide magnetic gel microspheres according to a preferred embodiment of the ulva polysaccharide magnetic gel microspheres of the present invention;

[0028] Figure 5 This is a graph showing the XRD analysis results of the ulva polysaccharide / chitosan oligosaccharide composite gel according to a preferred embodiment of the magnetic gel microspheres of ulva polysaccharide of the present invention. DETAILED DESCRIPTION

[0029] In order to make the technical solution of the present invention more clear and specific to those skilled in the art, the present invention is further described in detail below with reference to embodiments and drawings, but the embodiments of the present invention are not limited thereto.

[0030] Example 1;

[0031] A magnetic particle formation method comprises the following steps: S1, dissolving FeCl3-6H20 and FeSO4-7H20 in 20 mL of ultrapure water, with a concentration of 0.01 mol.

[0032] S2. Dissolve in ultrasonic water at 50°C under N2 protection, stir for 5 minutes and mix evenly.

[0033] S3. Add graphene oxide solution (20 mL) to the mixed solution and continue stirring for 10 minutes.

[0034] S4. Subsequently, 15 mL of ammonium hydroxide was added dropwise to the reaction system, and the reaction was continued at 50° C. for 1.5 h.

[0035] S5. Then, the reaction system was heated to 70°C and heated to mature for 1 hour.

[0036] S6. After the reaction is completed, the mixture is filtered and washed with ultrapure water until it is neutral.

[0037] S7. Dry the washed ferroferric oxide magnetic particle mixture and dissolve it in ultrapure water at a concentration of 1 mg / mL.

[0038] Image characterization of formed magnetic particles, such as Figure 1 shown.

[0039] The results showed that under the action of magnet, the magnetic particles aggregated rapidly, indicating that the magnetic particles were successfully synthesized.

[0040] Example 2;

[0041] The formation of Ulva polysaccharide magnetic gel particles comprises the following steps:

[0042] S7, drying the washed ferroferric oxide magnetic particle mixture, and dissolving it in ultrapure water at a concentration of 1 mg / mL;

[0043] S8, crushing the dried Ulva green algae into powder, defatting and drying the powder, extracting crude Ulva polysaccharides using hot water extraction, and freeze-drying the powder;

[0044] S9. Dissolve the lyophilized sample in water at 45-50 mg / mL, add 1 / 4 volume of Sevag reagent (n-butanol:chloroform = 1:4), and repeat 9-12 times to obtain a purified polysaccharide solution;

[0045] S10, dialyzing the polysaccharide solution for 24 to 36 hours using a dialysis bag with a cutoff of 3500 Daltons, and then collecting the sample for freeze-drying;

[0046] S11. Take Ulva polysaccharide (purity greater than 90%), dissolve it in the magnetic particle solution (20-30 mg / mL) prepared in S7, heat it in a water bath at 60 degrees Celsius, and mix it every half hour.

[0047] S12. Prepare 0.1 M ferric chloride solution in a beaker;

[0048] S13, then, injecting the Ulva polysaccharide / magnetic particle mixed solution into the 0.1 M ferric chloride solution using a constant speed propeller;

[0049] S14, soaking and aging for 1 hour, freezing and drying to obtain Ulva polysaccharide magnetic gel microspheres;

[0050] The image characterization of the formed Ulva polysaccharide magnetic gel microspheres was performed, such as Figure 2 shown.

[0051] The results show that the gel microspheres prepared by combining magnetic particles (Fe3O4) with Ulva polysaccharide successfully achieved magnetic response performance. This property gives the material important functional advantages. The microspheres can complete directional movement within 1 minute under the action of an external magnetic field.

[0052] Example 3;

[0053] This example is used to determine the size of the Ulva polysaccharide magnetic gel microspheres prepared in Example 3;

[0054] The specific method is as follows: Place the Ulva polysaccharide magnetic gel microspheres under a microscope for observation and magnification, and then use a marking tool to mark the size, such as Figure 3 As shown;

[0055] The results showed that the prepared Ulva polysaccharide magnetic gel microspheres had a relatively uniform size distribution, with an average diameter of about 2.0±0.02mm (n≥6);

[0056] Example 4;

[0057] This example is used to determine the internal structure of the Ulva polysaccharide magnetic gel microspheres prepared in Example 2;

[0058] The specific method is as follows:

[0059] cryo-electron microscopy (Cryo-EM) and pore size analysis;

[0060] Cryo-EM sample preparation followed the protocols in Sections 2.2 and 2.3. The steps were summarized as follows: plunge freezing was performed in liquid ethane using a Vitrobot Mark IV (Thermo Fisher Scientific), and cryo-EM data were acquired on a 30 kV Itan Krios microscope (Thermo Fisher Scientific) equipped with a Gatan K3 direct electron detector.

[0061] result Figure 4 The results showed that at 5000x magnification, the Ulva polysaccharide magnetic gel microspheres exhibited a typical interconnected porous network structure. This three-dimensional, interconnected pore structure not only gives the material a high specific surface area and porosity, but also may facilitate the loading and sustained release of nutrients or drugs. Further high-magnification observation revealed that the internal structure of the microspheres was uniformly distributed, and the Fe3O4 magnetic particles were evenly dispersed within the Ulva polysaccharide matrix network, with no obvious agglomeration.

[0062] Example 5;

[0063] This example is used to evaluate the infrared analysis results and formation mechanism of the Ulva polysaccharide magnetic gel microspheres prepared in Example 1;

[0064] The specific method is as follows:

[0065] The crystal structure of the sample was analyzed by X-ray diffractometer. The test conditions are as follows: Radiation source: CuKα ray The operating voltage was 40 kV and the current was 40 mA. The scanning range was 5°-80° (2θ), the scanning rate was 4° / min, and the step size was 0.02°. The dried sample was ground into a uniform powder and placed in a glass sample tank and pressed flat. The room temperature (25 ± 1°C) was maintained during the test, and each sample was measured three times to ensure data reliability.

[0066] According to the above results, after Ulva polysaccharide reacts with trivalent iron to form magnetic gel microspheres, the peak width of the C peak (2θ≈20℃) in its XRD spectrum increases significantly. This indicates that there is a coordination cross-linking effect in the formation of the gel microspheres: Fe 3+ As a cross-linking center, it binds to multiple ULP chains, causing the conformation of the polysaccharide chain to change from a loose coil to a compact aggregate state. This indicates that aggregates different from the original polysaccharide chains are formed during the formation of gel microspheres, further indicating the polymerization of magnetic particles and the wrapping effect of sugar chains during the formation of gel microspheres.

[0067] The above is only a further embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes based on the technical solutions and concepts of the present invention within the scope disclosed by the present invention, which fall within the scope of protection of the present invention.

Claims

1. A magnetic gel microsphere of Ulva polysaccharide, characterized by: The magnetic gel microspheres are composed of a composite of ulva polysaccharide and magnetic particles, and have a three-dimensional porous network structure. The magnetic particles are uniformly dispersed in the ulva polysaccharide matrix, and the average diameter of the microspheres is 2.0±0.02 mm.

2. The magnetic gel microspheres of Ulva polysaccharide according to claim 1, characterized in that: The magnetic particles are Fe3O4 magnetic particles, which can be rapidly aggregated under the action of a magnet.

3. The magnetic gel microspheres of Ulva polysaccharide according to claim 2, characterized in that: The purity of the ulva polysaccharide is greater than 90%.

4. The magnetic gel microspheres of Ulva polysaccharide according to claim 3, characterized in that: The microspheres can complete directional movement within 1 minute under the action of an external magnetic field.

5. The magnetic gel microspheres of Ulva polysaccharide according to claim 4, characterized in that: The pore size distribution of the porous network structure of the microspheres is expressed as mean ± standard deviation, and the dominant pore size range is determined by histogram and Gaussian fitting.

6. The magnetic gel microspheres of Ulva polysaccharide according to claim 5, characterized in that: The raw materials for preparing the microspheres include FeCl3·6H2O, FeSO4·7H2O, graphene oxide solution, ammonium hydroxide, Ulva green algae, Sevag reagent and ferric chloride solution.

7. The magnetic gel microspheres of Ulva polysaccharide according to claim 6, characterized in that: The concentrations of FeCl3·6H2O and FeSO4·7H2O in ultrapure water are both 0.01 mol.

8. The magnetic gel microspheres of Ulva polysaccharide according to claim 7, characterized in that: The Sevag reagent is prepared by mixing n-butanol and chloroform in a volume ratio of 1:

4.

9. The magnetic gel microspheres of Ulva polysaccharide according to claim 8, characterized in that: The concentration of the ferric chloride solution is 0.1M.

10. The magnetic gel microspheres of Ulva polysaccharide according to claim 9, characterized in that: The preparation method of the microspheres comprises the following steps: Dissolve FeCl3·6H2O and FeSO4·7H2O in ultrapure water, stir in ultrapure water at 50°C under N2 protection, add graphene oxide solution and then drop ammonium hydroxide to react, heat to mature, filter and wash until neutral, dry and dissolve in ultrapure water; The green algae Ulva was crushed, defatted and dried, crude polysaccharides were extracted by hot water extraction and freeze-dried, dissolved in water and repeatedly treated with Sevag reagent, dialyzed and freeze-dried; The ulva polysaccharide is dissolved in a magnetic particle solution, heated in a water bath, injected with a ferric chloride solution, immersed in alcoholization, and freeze-dried to obtain microspheres.

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