阅读说明：本技术 一种高强韧仿生肌肉水凝胶材料及其制备方法和应用 (High-toughness bionic muscle hydrogel material and preparation method and application thereof ) 是由 余亚东 刘昭明 唐睿康 于 2019-09-10 设计创作，主要内容包括：本发明公开了一种高强韧仿生肌肉水凝胶材料,所述高强韧仿生肌肉水凝胶材料包括10～40wt％的磷酸钙纳米簇和60～90wt％的有机物,所述有机物包括聚乙烯醇和海藻酸钠,所述聚乙烯醇和海藻酸钠的质量比为8:1～3:1。本发明还公开了一种高强韧仿生肌肉水凝胶材料的制备方法和在软体机器人或生物组织工程领域上的应用。本发明提供的仿生肌肉水凝胶材料具有高强度和高韧性；提供的制备方法为构建具有分级有序结构的有机-无机复合水凝胶提出了新的制备策略,所制备的类肌肉水凝胶在软体机器人,生物组织工程领域具有巨大的应用前景。(The invention discloses a high-toughness bionic muscle hydrogel material which comprises 10-40 wt% of calcium phosphate nanoclusters and 60-90 wt% of organic matters, wherein the organic matters comprise polyvinyl alcohol and sodium alginate, and the mass ratio of the polyvinyl alcohol to the sodium alginate is 8: 1-3: 1. The invention also discloses a preparation method of the high-toughness bionic muscle hydrogel material and application of the high-toughness bionic muscle hydrogel material in the field of soft robots or biological tissue engineering. The bionic muscle hydrogel material provided by the invention has high strength and high toughness; the preparation method provides a new preparation strategy for constructing the organic-inorganic composite hydrogel with the hierarchical ordered structure, and the prepared muscle-like hydrogel has great application prospect in the fields of soft robots and biological tissue engineering.)

1. The high-toughness bionic muscle hydrogel material is characterized by comprising 10-40 wt% of calcium phosphate nanoclusters and 60-90 wt% of organic matters, wherein the organic matters comprise polyvinyl alcohol and sodium alginate, and the mass ratio of the polyvinyl alcohol to the sodium alginate is 8: 1-3: 1.

2. The high-toughness bionic muscle hydrogel material as claimed in claim 1, wherein the high-toughness bionic muscle hydrogel material comprises 20-35 wt% of calcium phosphate nanoclusters and 65-80 wt% of organic matters, the organic matters comprise polyvinyl alcohol and sodium alginate, and the mass ratio of the polyvinyl alcohol to the sodium alginate is 6: 1.

3. The high-toughness bionic muscle hydrogel material as claimed in any one of claims 1 to 2, wherein the particle size of the calcium phosphate nanocluster is 1.15 ± 0.23 nm.

4. A method for preparing the high-toughness bionic muscle hydrogel material as claimed in any one of claims 1 to 2, which is characterized by comprising the following steps:

(1) calcium phosphate nanoclusters are used as precursors of inorganic crystallization units, and sodium alginate aqueous solution and polyvinyl alcohol aqueous solution are added to form uniform emulsion in a compounding mode;

(2) the emulsion is subjected to evaporation-induced self-assembly to obtain an isotropic composite film;

(3) immersing the isotropic composite film prepared in the step (2) in water to achieve swelling balance, taking out the isotropic composite film, stretching the isotropic composite film to a part of the structure for rearrangement, and immersing the isotropic composite film in water again to achieve swelling balance to obtain a muscle-like gel film with an ordered structure;

(4) and (3) stacking the single-layer muscle-like gel films prepared in the step (3) layer by layer, using the emulsion in the step (1) as glue to perform interlayer bonding, applying pressure, unloading the pressure, and then immersing the films in water again to achieve swelling balance to obtain the three-dimensional bionic muscle hydrogel.

5. The preparation method of the high-toughness bionic muscle hydrogel material as claimed in claim 4, wherein the preparation method of the calcium phosphate nanoclusters in the step (1) is as follows: triethylamine is used as a stabilizer, calcium salt is used as a calcium source, phosphoric acid is used as a phosphorus source, the calcium salt and the phosphoric acid are added into an organic solvent to generate a calcium phosphate nano cluster, the concentration of the calcium salt in the organic solvent is 0.001-0.1 mol/L, the molar ratio of the calcium salt to the phosphoric acid is 1-2, and the concentration of the triethylamine is 0.02-1 mol/L.

6. The preparation method of the high-strength high-toughness bionic muscle hydrogel material as claimed in claim 4, wherein the stretching strain in the step (3) is 50-200%.

7. The preparation method of the high-strength high-toughness bionic muscle hydrogel material as claimed in claim 4, wherein the stress applied in the step (4) is 5-20 KPa, and the stress is kept constant for 24-48 h.

8. The application of the high-toughness bionic muscle hydrogel material according to any one of claims 1-2 in the field of soft robots or biological tissue engineering.

Technical Field

The invention belongs to the technical field of high-toughness tissue engineering materials, and particularly relates to a high-toughness bionic muscle hydrogel material and a preparation method and application thereof.

Background

Muscle is used as a soft organism material, is a natural hydrogel, has the water content of 70-80 wt%, has excellent mechanical properties and is mainly represented by high strength (1 MPa) and high breaking energy (1000J m)^-2). The performance of current synthetic hydrogel materials often cannot achieve similar performance levels as natural muscles in both strength and toughness due to the special hierarchical ordered structure of muscles. Inspired by this, the research of the bionic muscle hydrogel has become a research hotspot in the field of high-performance hydrogel. For example, the bionic muscle hydrogel prepared by compounding polyacrylamide and natural ordered wood fibers has excellent mechanical properties and ionic conductivity; the anti-fatigue bionic muscle hydrogel is prepared by polyvinyl alcohol through chemical crosslinking and a freezing-melting method.

For example, chinese patent publication No. CN107737370A discloses a method for preparing a high-strength, superelastic, conductive hydrogel for cartilage repair, and belongs to the technical field of biomaterials. The invention constructs 'bone-muscle' hydrogel with good mechanical property and electrical conductivity by imitating the structure of a human body; firstly, preparing a natural polymer/nano filler composite porous support with good adsorption performance by using a freeze-drying method; secondly, adsorbing and dispersing hydrogel pre-polymerization liquid of a polydopamine modified conductive material by using the bracket, and finally polymerizing to form bone-muscle hydrogel; the natural polymer/nano filler support obviously improves the mechanical property of the hydrogel, and can provide enough mechanical strength and extracellular matrix microenvironment for the repair of cartilage tissues; in addition, the hydrogel has good conductivity, and can respond to external electrical stimulation to promote the repair and regeneration of cartilage tissues; the method has important research value in the aspects of improving the mechanical property of the hydrogel, expanding the clinical application of the hydrogel and the like. For example, chinese patent publication No. CN107973881A discloses a preparation method of a high-tensile hydroxyethyl cellulose/polyacrylamide composite hydrogel, which comprises the following steps: certain amount of acrylamide, hydroxyethyl cellulose, deionized water and tetramethyl ethylenediamine are mixed homogeneously and stirred continuously to form transparent liquid. And (3) placing the transparent liquid in an ice bath environment, adding a small amount of ammonium persulfate serving as an initiator, fully stirring, and then placing in an environment at 40-60 ℃ for reaction for 8 hours. The hydrogel takes hydroxyethyl cellulose, polyacrylamide and water as raw materials, and the content of the added hydroxyethyl cellulose is adjusted, so that the composite hydrogel with high stretchability is obtained. The method utilizes the characteristics of the hydroxyethyl cellulose, applies the hydroxyethyl cellulose to the aspect of toughening and reinforcing the hydrogel, and the used hydroxyethyl cellulose is a biomass material and has biocompatibility, so the method is a green method for toughening and reinforcing the hydrogel and has good application prospect.

Generally, it is difficult to achieve a hierarchical structure similar to that of natural muscle in a nano-scale by using the current synthetic hydrogel. How to construct hydrogels with muscle-like ordered fibrous structures is currently still a great challenge.

Disclosure of Invention

The invention aims to provide a high-strength and high-toughness bionic muscle hydrogel material which has high strength and high toughness, and also provides a preparation method of the high-strength and high-toughness bionic muscle hydrogel material, the high-strength and high-toughness bionic muscle hydrogel material with a hierarchical ordered structure can be constructed, and the prepared high-strength and high-toughness bionic muscle hydrogel material can be applied to the fields of soft robots and biological tissue engineering.

The invention provides the following technical scheme:

the high-toughness bionic muscle hydrogel material comprises 10-40 wt% of calcium phosphate nanoclusters and 60-90 wt% of organic matters, wherein the organic matters comprise polyvinyl alcohol and sodium alginate, and the mass ratio of the polyvinyl alcohol to the sodium alginate is 8: 1-3: 1.

Preferably, the high-strength and high-toughness bionic muscle hydrogel material comprises 20-35 wt% of calcium phosphate nano clusters and 65-80 wt% of organic matters, wherein the organic matters comprise polyvinyl alcohol and sodium alginate, and the mass ratio of the polyvinyl alcohol to the sodium alginate is 6: 1.

Preferably, the particle size of the calcium phosphate nanocluster is 1.15 +/-0.23 nm.

The invention also provides a preparation method of the high-toughness bionic muscle hydrogel material, which comprises the following steps:

(1) calcium phosphate nanoclusters are used as precursors of inorganic crystallization units, and sodium alginate aqueous solution and polyvinyl alcohol aqueous solution are added to form uniform emulsion in a compounding mode;

(2) the emulsion is subjected to evaporation-induced self-assembly to obtain an isotropic composite film;

(3) immersing the isotropic composite film prepared in the step (2) in water to achieve swelling balance, taking out the isotropic composite film, stretching the isotropic composite film to a part of the structure for rearrangement, and immersing the isotropic composite film in water again to achieve swelling balance to obtain a muscle-like gel film with an ordered structure;

(4) and (3) stacking the single-layer muscle-like gel film prepared in the step (3) layer by layer (more than or equal to 2 layers, wherein the thickness of the single-layer hydrogel film is 100-2000 microns, and the single-layer hydrogel film can be stacked in an infinite layer according to the thickness of hydrogel as required), using the emulsion in the step (1) as glue to perform interlayer bonding, applying stress, unloading the pressure, and then immersing the glue into water again to achieve swelling balance to obtain the three-dimensional phase bionic muscle hydrogel material.

The preparation method of the calcium phosphate nanocluster in the step (1) comprises the following steps: triethylamine is used as a stabilizer, calcium salt is used as a calcium source, phosphoric acid is used as a phosphorus source, the calcium salt and the phosphoric acid are added into an organic solvent to generate a calcium phosphate nano cluster, the concentration of the calcium salt in the organic solvent is 0.001-0.1 mol/L, the molar ratio of the calcium salt to the phosphoric acid is 1-2, and the concentration of the triethylamine is 0.02-1 mol/L.

The organic solvent is selected from one or the combination of at least two of ethanol, glycol or glycerol. The polyvinyl alcohol in the step (1) forms an organic main network structure of the composite film; in the process of forming the composite film, the calcium phosphate nano-cluster gradually changes into crystalline hydroxyapatite and is combined with sodium alginate molecules through ionic bonds. The sodium alginate is used as a bridging molecular material for connecting polyvinyl alcohol and calcium phosphate, so that the network of the composite film becomes an organic-inorganic double network, the structure is tighter, and the performance is more excellent.

Preferably, the concentration of the calcium salt in the organic solvent is 0.02-0.05 mol/L, the molar ratio of the calcium salt to the phosphoric acid is 1-1.67, and the concentration of the triethylamine is 0.02-0.5 mol/L.

In the step (1), composite films with different strengths and toughness can be obtained by adjusting the addition amount (10-30 wt%) of the calcium phosphate nanoclusters.

In the step (1), the concentration of the polyvinyl alcohol aqueous solution is 1-10 wt%, and the concentration of the sodium alginate aqueous solution is 0.1-2 wt%.

And (3) soaking the isotropic composite prepared in the step (2) in water for 5-60 min to achieve swelling balance. Preferably, the water is soaked in the water for 5-20 min to reach the swelling balance.

And (4) stretching to a strain of 50-200% in the step (3).

The stress applied in the step (4) is 5-20 KPa, and the stress is kept constant for 24-48 h. The layers are tightly connected by applying stress.

The invention also provides application of the high-toughness bionic muscle hydrogel material in the field of soft robots or biological tissue engineering.

The high-strength and high-toughness bionic muscle hydrogel material provided by the invention is high-strength and high-toughness large-size bionic muscle hydrogel. The preparation method provided by the invention is a two-step assembly method (evaporation-induced self-assembly method for preparing homogeneous composite films and stress-induced assembly ordered hydrogel), which is a preparation method combining from bottom to top and from top to bottom, provides a new preparation strategy for constructing organic-inorganic composite hydrogel with a hierarchical ordered structure, and the prepared muscle-like hydrogel has great application prospect in the fields of soft robots and biological tissue engineering.

Drawings

FIG. 1 is a process flow diagram of a preparation method provided by the present invention;

FIG. 2 is a schematic diagram of the form and internal structure of the high-toughness bionic muscle hydrogel material prepared by the embodiment;

FIG. 3 is a schematic diagram of mechanical properties of a high-toughness bionic muscle hydrogel material prepared by the embodiment;

fig. 4 is a schematic diagram of bending, twisting and bearing performances of the high-toughness bionic muscle hydrogel material prepared in the embodiment.

Detailed Description

As shown in fig. 1, it is a process flow of the high-toughness bionic muscle hydrogel material provided by the invention and a network structure inside the material. The preparation method comprises the following steps: calcium phosphate nanoclusters are used as an inorganic unit precursor, a sodium alginate solution and a polyvinyl alcohol aqueous solution are sequentially added, a composite film is prepared through an emulsion evaporation induction self-assembly method, then the film is soaked in water for 5-10 min, the film is taken out and is directionally and repeatedly stretched to 50-200% of strain, the internal structure is rearranged and is changed from a disordered net structure to an orderly chain structure, and hydroxyapatite nanocrystals form an orderly crystal array under the drive of a polymer chain.