Preparation method and application of erasable hydrogel material

Abstract

The present invention provides a preparation method and application of an erasable hydrogel material, belonging to the field of new material technology. The hydrogel is prepared from carboxyl-containing monomers, multivalent metal ion compounds and ethylenediaminetetraacetic acid as raw materials. By changing the ratio of divalent metal ions and trivalent metal ions, hydrogels with different rheological properties are obtained, which are used as erasable hydrogel materials. When used as a liquid-confined erasable reaction container, this hydrogel material has the advantages of both solid containers and liquid containers, and has the characteristics of being independent of base materials, easily erasable and having multiple functions. The raw materials for preparing the hydrogel are simple, the preparation method and operation procedures are simple and environmentally friendly, and it has good application prospects.

Description

Technical Field

[0001] The present invention relates to a liquid confinement material, belonging to the technical field of new materials, and particularly to a preparation method and application of an erasable hydrogel material. Background Art

[0002] The information disclosed in this background technology section is only intended to enhance understanding of the overall background of the invention and should not necessarily be regarded as an admission or any form of suggestion that the information constitutes the prior art already known to those skilled in the art.

[0003] Hydrogels are colloidal materials with a three-dimensional cross-linked network structure, typically constructed through chemical cross-linking between polymers. Due to their high water content, hydrogels have found widespread application in biomedical engineering, including the preparation of tissue engineering scaffolds, drug carriers, biosensors, wound dressings, and coatings for implantable medical devices. Erasable hydrogels are a type of smart material that can be used in a variety of applications, including surface patterning, writing, and information encryption. These materials can dissociate spontaneously or in response to external stimuli (e.g., pH changes or light signals).

[0004] Throughout human history, solid containers such as pottery, vases, metal jars, or glass have been used to confine, store, and process liquids. Solid containers are also commonly used in laboratories, but they have some problems, such as being difficult to remove and reshape, and the risk of contaminating the contents during reuse. People have proposed a variety of solutions to address the problems of solid containers. For example, the research group of Professor Thomas M. Hermans in France proposed placing concentric liquid pipes formed by an internal aqueous liquid and an immiscible magnetic liquid in a magnetic field to achieve solid wall-free control of liquid flow. Foss et al. used the self-assembly of colloids at the interface to shape liquids into complex 3D objects, and injected aqueous nanoparticles and surfactants into silicone oil to form a yield-dissipating structure that can be used as a two-phase reaction container. Jokinen et al. demonstrated the use of superhydrophobic-hydrophilic patterns to generate multiphase droplets on a silicon nanograss substrate to confine organic droplets within water droplets for small-scale extraction applications. Levkin proposed the concept of liquid wells and fabricated a series of liquid wells of different shapes that can be used as non-solid self-healing containers for confining low-surface tension liquids at different scales on pre-patterned substrates. Although these liquid-based solutions overcome the limitations of solid containers, complex system designs, such as the need for external magnetic fields or pre-patterning of substrates, also limit the application of liquid containers. Summary of the Invention

[0005] In response to the numerous problems existing in the above-mentioned solid containers and liquid containers, the present invention provides a method for preparing an erasable hydrogel material. The preparation method of the hydrogel has simple operation procedures and high repeatability, making the hydrogel highly practical.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A first aspect of the present invention provides a method for preparing an erasable hydrogel material, comprising:

[0008] preparing a carboxyl group-containing monomer and citric acid into a solution to obtain a carboxyl group-containing monomer solution;

[0009] Dissolving a divalent metal ion compound and a trivalent metal ion compound in an ethylenediaminetetraacetic acid aqueous solution respectively, and then mixing the two to obtain a mixed solution;

[0010] The carboxyl group-containing monomer solution is mixed with the mixed solution, and solidified under ultrasonic conditions to obtain the product.

[0011] The present invention develops an erasable hydrogel material that can be applied to liquid confinement fields on any substrate, maintaining any shape without any external assistance, and has potential research value and application prospects.

[0012] The second aspect of the present invention provides an erasable hydrogel material prepared by the above method.

[0013] Beneficial effects of the present invention

[0014] (1) The hydrogel of the present invention is an erasable hydrogel formed by cross-linking of variable valence metal ions and carboxyl-containing monomers. The molecules are bound by metal coordination and have the property of being erasable by water; erasing principle: citric acid in the present invention is an essential component for achieving erasable performance; under the assistance of light conditions, deionized water washing can remove trivalent metal ions (Fe 3 + 、Co 3+ ) is reduced to divalent metal ions (Fe 3+ 、Co 3+ ), which reduces the metal coordination cross-linking strength between molecules, thereby achieving gel-sol transition.

[0015] (2) The hydrogel of the present invention has simple raw materials for preparation, and the preparation method is simple and environmentally friendly, and has good application prospects.

[0016] (3) The hydrogel of the present invention is used as a reaction container, which has the advantages of both solid containers and liquid containers, is independent of the base material, can be easily erased, and has multiple functions.

[0017] (4) The preparation method of the present invention is simple, practical, and easy to promote. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The drawings in the specification, which constitute a part of this application, are used to provide further understanding of this application. The illustrative embodiments of this application and their descriptions are used to explain this application and do not constitute improper limitations on this application.

[0019] Figure 1 These are the viscosity test results of the hydrogel materials prepared in Examples 1-5.

[0020] Figure 2 This is a demonstration of the application of the erasable hydrogel of the present invention to draw reaction containers of arbitrary shapes on glass and PTFE substrate materials.

[0021] Figure 3 This is the erasing process after the erasable hydrogel of the present invention is used as a reaction container on a PTFE, PVC, or Quartz substrate material. DETAILED DESCRIPTION

[0022] It should be noted that the following detailed description is illustrative and is intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used in the present invention have the same meaning as commonly understood by those skilled in the art to which the present application belongs.

[0023] Explanation of terms

[0024] Erasable hydrogels are polymer hydrogel materials that can, under certain conditions, transition from a gel (solid) state to a sol (liquid) state. These include two main types: spontaneous erasure (usually driven by adding chemical fuels to the prepolymer) and erasure in response to external stimuli (pH changes, light signals, solution composition, temperature, inorganic salts, electric fields, etc.).

[0025] A method for preparing an erasable hydrogel material, comprising:

[0026] 1) dissolving a certain amount of carboxyl group-containing monomer in a phosphate buffer solution and adjusting the pH value to 7.0-8.0 to obtain a carboxyl group-containing monomer solution;

[0027] 2) Weighing a certain amount of a divalent metal ion compound and dissolving it in an EDTA aqueous solution to obtain a mixed solution A;

[0028] 3) Weighing a certain amount of a trivalent metal ion compound and dissolving it in an EDTA aqueous solution to obtain a mixed solution B;

[0029] 4) mixing the mixed solution A and the mixed solution B in a certain volume ratio to obtain a mixed solution of the multivalent metal ion compound and ethylenediaminetetraacetic acid;

[0030] 5) The carboxyl group-containing monomer solution is mixed with the mixed solution of the multivalent metal ion compound and ethylenediaminetetraacetic acid in a certain volume ratio, and the mixture is cured under ultrasound-assisted conditions to obtain the erasable hydrogel.

[0031] Furthermore, the carboxyl group-containing monomer is one or a mixture of two or more of hyaluronic acid, sodium alginate, methacrylic acid, sodium oleate, lauric acid, and DL-sodium mandelate.

[0032] Preferably, the carboxyl group-containing monomer solution is a mixed solution of hyaluronic acid and sodium alginate;

[0033] Preferably, the concentration of hyaluronic acid is 0-1% (w / v), and the concentration of sodium alginate is 1-5% (w / v).

[0034] Furthermore, the multivalent metal ion compound is an Fe ion compound or a Co ion compound.

[0035] Preferably, the multivalent metal ion compound is ferrous sulfate or ferric sulfate;

[0036] Furthermore, the concentration of the divalent metal ions in the mixed solution A is 0.1 mol / L to 1 mol / L, and the concentration of ethylenediaminetetraacetic acid is 0.01 mol / L to 0.1 mol / L;

[0037] Preferably, the concentration of divalent metal ions in the mixed solution A is 0.1 mol / L, and the concentration of EDTA is 0.05 mol / L.

[0038] Furthermore, the concentration of trivalent metal ions in the mixed solution B is 0.1 mol / L to 1 mol / L, and the concentration of ethylenediaminetetraacetic acid is 0.01 mol / L to 0.1 mol / L;

[0039] Preferably, the concentration of trivalent metal ions in the mixed solution B is 0.5 mol / L, and the concentration of EDTA is 0.05 mol / L.

[0040] Furthermore, the volume ratio of mixed solution A to mixed solution B is 1:0.1 to 10; among them, under the condition of mixed solution A: mixed solution B = 1:3, the prepared hydrogel material has the best shear thinning performance and can maintain the stability of structure and shape on any substrate material (polytetrafluoroethylene-PTFE, polyvinyl chloride-PVC, quartz). Therefore, the required reaction vessel shape can be drawn according to actual needs.

[0041] Furthermore, the volume ratio of the carboxyl group-containing monomer solution to the mixed solution of the multivalent metal ion compound and ethylenediaminetetraacetic acid is (1-100):1.

[0042] Furthermore, the volume ratio of the carboxyl group-containing monomer solution to the mixed solution of the multivalent metal ion compound and ethylenediaminetetraacetic acid is (1-20):1;

[0043] Preferably, the volume ratio of the carboxyl group-containing monomer solution to the mixed solution of the multivalent metal ion compound and ethylenediaminetetraacetic acid is 3:1.

[0044] The present invention also discloses an application of the prepared hydrogel material in the field of erasable reaction containers, which specifically comprises the following steps:

[0045] 1) placing the hydrogel material into an injection device with a specific pore size at room temperature;

[0046] 2) Control the angle, speed and height of the injection device to draw any desired closed loop shape on the required base material according to specific needs.

[0047] Allow to cure at room temperature and then use as an erasable reaction container for liquid confinement.

[0048] The present invention will be further described in detail below with reference to specific embodiments. It should be noted that the specific embodiments are intended to explain the present invention rather than to limit it.

[0049] Example 1:

[0050] 1) Weigh 1 g of hyaluronic acid, 5 g of sodium alginate, and 1.92 g of citric acid, respectively, and dissolve them in 100 mL of phosphate buffer solution. Adjust the pH to 7.0 to obtain a mixed solution of hyaluronic acid and sodium alginate.

[0051] 2) Weigh 2.78 g of FeSO4·7H2O solid and dissolve it in 100 mL of 0.05 mol / L EDTA aqueous solution to obtain mixed solution A; 2+ The concentration is 0.1mol / L.

[0052] 3) Weigh 19.99g of Fe2S3O 12 xH2O solid is dissolved in 100mL of 0.05mol / L ethylenediaminetetraacetic acid aqueous solution. A certain mass of trivalent metal ion compound is dissolved in ethylenediaminetetraacetic acid aqueous solution to obtain mixed solution B; Fe 3+ The concentration is 0.5mol / L.

[0053] 4) Take 10mL of mixed solution A and 1mL of mixed solution B to mix to obtain Fe 2+ / Fe 3+ Ethylenediaminetetraacetic acid mixed solution;

[0054] 5) Take 3mL of the mixed solution of hyaluronic acid and sodium alginate and 1mL of Fe 2+ / Fe 3+ The ethylenediaminetetraacetic acid mixed solution is mixed and solidified under ultrasonic-assisted conditions to obtain the erasable hydrogel material cross-linked by Fe ions.

[0055] Example 2-5:

[0056] In Example 2-5, steps (1), (2), (3) and (5) are the same as in Example 1, except that the mixing ratio of solution A and solution B in step (4) is different. The volumes of solution A and solution B used in step (4) in Example 2-5 are shown in Table 1.

[0057] Table 1 Volume of solution A and solution B used in Examples 1-5

[0058]

[0059] The viscosity change results of the hydrogel materials prepared in Examples 1-5 are as follows: Figure 1 As shown in , the amount of solution B increases. 500 μL of the hydrogel material prepared in Example 4 was placed on glass and polytetrafluoroethylene substrates to prepare a liquid confinement reaction vessel. Figure 2 As shown, after curing at room temperature, the prepared hydrogel material exhibits excellent stability and self-sustaining ability, and can be drawn into any required shape and remain stable without any external assistance. Figure 3 The process of erasing the liquid-confined reaction container drawn on polytetrafluoroethylene, polyvinyl chloride and quartz substrate materials by 500 μL of the hydrogel material prepared in Example 4 with deionized water is shown. Figure 3 It can be seen that only 10 mL of deionized water needs to be added for 5 seconds to make the solidified hydrogel return to liquid state.

[0060] Example 6:

[0061] 1) Weigh 1 g of hyaluronic acid, 1 g of sodium alginate, and 1.92 g of citric acid, respectively, and dissolve them in 100 mL of phosphate buffer solution. Adjust the pH to 8.0 to obtain a mixed solution of hyaluronic acid and sodium alginate.

[0062] 2) Weigh 2.81 g of CoSO4·7H2O solid and dissolve it in 100 mL of 0.05 mol / L ethylenediaminetetraacetic acid aqueous solution to obtain mixed solution A; 2+ The concentration is 0.1mol / L.

[0063] 3) Weigh 20.19g of Na3CoN6O 12The solid was dissolved in 100 mL of 0.05 mol / L ethylenediaminetetraacetic acid aqueous solution. A certain mass of trivalent metal ion compound was dissolved in ethylenediaminetetraacetic acid aqueous solution to obtain a mixed solution B; wherein Co 3+ The concentration is 0.5mol / L.

[0064] 4) Take 10mL of mixed solution A and 1mL of mixed solution B to mix to obtain Co 2+ / Co 3+ Ethylenediaminetetraacetic acid mixed solution;

[0065] 5) Take 3mL of the mixed solution of hyaluronic acid and sodium alginate and 1mL of Co 2+ / Co 3+ The ethylenediaminetetraacetic acid mixed solution was mixed and solidified under ultrasound-assisted conditions to obtain a Co-crosslinked erasable hydrogel material.

[0066] The above description is merely a preferred embodiment of the present application and is not intended to limit the present application. Various modifications and variations are possible for those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A method for preparing an erasable hydrogel material, characterized in that: include: The carboxyl group-containing monomer is prepared into a solution to obtain a carboxyl group-containing monomer solution, and citric acid is added to adjust the pH value to 7.0-8.0; Dissolving a divalent metal ion compound and a trivalent metal ion compound in an ethylenediaminetetraacetic acid aqueous solution to obtain a mixed solution A and a mixed solution B, respectively, and then mixing the two to obtain a mixed solution; The carboxyl group-containing monomer solution is mixed with the mixed solution, and solidified under ultrasonic conditions to obtain; The divalent metal ion compound and the trivalent metal ion compound are Fe ion compound and Co ion compound; In mixed solution A, the concentration of divalent metal ions is 0.1 mol / L to 1 mol / L, and the concentration of EDTA is 0.01 mol / L to 0.1 mol / L; In mixed solution B, the concentration of trivalent metal ions is 0.1 mol / L to 1 mol / L, and the concentration of EDTA is 0.01 mol / L to 0.1 mol / L; The volume ratio of mixed solution A to mixed solution B is 1:0.1~10; The volume ratio of the carboxyl group-containing monomer solution to the mixed solution is 1 to 100:1; The carboxyl-containing monomer solution is a mixed solution of hyaluronic acid and sodium alginate.

2. The method for preparing an erasable hydrogel material according to claim 1, wherein: In the mixed solution of hyaluronic acid and sodium alginate, the concentration of hyaluronic acid is 0~1% w / v.

3. The method for preparing an erasable hydrogel material according to claim 1, wherein: In the mixed solution of hyaluronic acid and sodium alginate, the concentration of sodium alginate is 1~5% w / v.

4. The method for preparing an erasable hydrogel material according to claim 1, wherein: The divalent metal ion compound is ferrous sulfate or the trivalent metal ion compound is ferric sulfate.

5. An erasable hydrogel material prepared by the method according to any one of claims 1 to 4.

6. The erasable hydrogel material according to claim 5, characterized in that: The hydrogel material is used to prepare a liquid-confined erasable reaction container.

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