MoS2 and Bi2S3 belongs to HA biological piezoelectric material as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of biomedical materials, and particularly relates to a MoS2 and Bi2S3 belonging to HA biological piezoelectric material as well as a preparation method and application of the MoS2 and Bi2S3 belonging to HA biological piezoelectric material. The preparation method comprises the following steps: growing a MoS2 thin layer on the surface of a Bi2S3 nanorod to prepare MoS2 and Bi2S3; the preparation method comprises the following steps: dispersing MoS2 at Bi2S3 into a hyaluronic acid solution to obtain MoS2 at Bi2S3 belonging to HA; the material has the following characteristics: (1) the activity of catalase-like and glutathione-like reductase is obviously enhanced under the ultrasonic action, and active oxygen is efficiently removed; hydrogen and electrical stimulation are generated in the inflammatory microenvironment through the piezoelectric effect, expression of inflammatory factors is inhibited, and cartilage repair is promoted. The preparation process of the material is simplified, the material is suitable for treating inflammatory joint diseases such as arthritis and synovitis, and targeted therapy can be achieved through local injection or articular cavity drug delivery.

Description

Technical Field

[0001] The present invention belongs to the technical field of biomedical materials, and particularly relates to a bio-piezoelectric material. Background Art

[0002] Rheumatoid arthritis (RA) is an autoimmune disease characterized by chronic synovial inflammation and progressive joint destruction. At present, the clinical treatment of RA mainly focuses on relieving inflammatory symptoms with drugs, such as taking non-steroidal anti-inflammatory drugs, glucocorticoids or disease-modifying anti-rheumatic drugs, etc. Although the symptoms can be relieved, it is unable to effectively repair damaged cartilage, and there are systemic toxic and side effects in long-term use. Since existing drugs rarely can effectively repair damaged cartilage tissue, the treatment effect of RA is greatly limited. For example, the prior art CN112755055A discloses that the combined application of Lactobacillus plantarum strain NA136 and cannabidiol monomer can alleviate the symptoms of arthritis in rats; reduce bone erosion and cartilage degeneration, but it is only limited to reducing cartilage damage and cannot achieve the purpose of repairing cartilage tissue. Inhibiting inflammation while repairing damaged cartilage is one of the key strategies for the efficient treatment of RA. Although the prior art CN119074762A discloses the application of MgAl-LDH in the preparation of drugs for treating joint inflammation, using MgAl-LDH (magnesium-aluminum layered double hydroxide) as a carrier to carry rhein (RH) with anti-inflammatory and cartilage repair activities, and combining it with a thermosensitive gel (Gel) to prepare LDH / RH-Ge for intra-articular injection, although it can achieve cartilage repair, it is a loaded type. Therefore, constructing a new type of nano-drug that combines inflammation inhibition and cartilage repair is expected to provide a new strategy for the efficient treatment of RA and fill the gap in RA treatment.

[0003] Although there are reports on the research of metal sulfide-doped nanomaterials, such as the patent CN108878159A reporting the construction of a composite nanomaterial based on MoS2 and Bi2S3, the latter focuses on improving the electrochemical performance (specific capacitance of 125.1 F / g) of 2D / 1D heterojunctions, which is specifically used for energy storage scenarios such as supercapacitors / lithium batteries, and the role of loading is to improve the electrochemical performance. On the other hand, whether it has inflammation inhibition and cartilage repair is unknown. In view of the above problems, it is urgent to explore new types of nano-drugs. Summary of the Invention

[0004] To solve the above technical problems, the present invention proposes a MoS2@Bi2S3∈HA bio-piezoelectric material and its preparation method and application.

[0005] To achieve the above object, the technical solution of the present invention is realized as follows:

[0006] A preparation method of MoS2@Bi2S3∈HA bio-piezoelectric material, the steps are as follows: Add MoS2@Bi2S3 into the hyaluronic acid solution and mix. After stirring at room temperature, the MoS2@Bi2S3∈HA bio-piezoelectric material is obtained, abbreviated as MoS2@Bi2S3∈HA.

[0007] The concentration of the above-mentioned hyaluronic acid solution is 0.25 - 3 mg / mL; the mass ratio of hyaluronic acid to MoS2@Bi2S3 in the hyaluronic acid solution is 2 - 80:1. Among them, the preparation method of the hyaluronic acid solution is: Disperse a certain amount of hyaluronic acid in ultrapure water, and after ultrasonic dispersion and swelling, the hyaluronic acid solution is obtained.

[0008] The preparation method of the above-mentioned MoS2@Bi2S3 is as follows:

[0009] (1) Mix Bi(NO3)3·5H2O, polyvinylpyrrolidone with the ethylene glycol solution containing Na2S·9H2O, and after the first hydrothermal reaction, Bi2S3 nanorods are obtained;

[0010] (2) Add the Bi2S3 nanorods, Na2MoO4·2H2O and NH2CSNH2 prepared in step (1) into deionized water for the second hydrothermal reaction to obtain MoS2@Bi2S3.

[0011] Furthermore, in the above step (1), the mass ratio of Bi(NO3)3·5H2O, polyvinylpyrrolidone to Na2S·9H2O is 1:1:0.72.

[0012] Furthermore, in the above step (1), the temperature of the hydrothermal reaction is 160 - 200 °C, and the time is 2 - 5 hours.

[0013] Furthermore, in the above step (2), the molar ratio of Na2MoO4·2H2O to Bi2S3 nanorods is 0.1 - 0.25:1, and the added mass of NH2CSNH2 is 5 times that of Na2MoO4·2H2O.

[0014] Furthermore, in the above step (2), the temperature of the hydrothermal reaction is 200 - 240 °C, and the time is 20 - 28 hours.

[0015] After the hydrothermal reaction in the above steps (1) and (2), it also includes washing, centrifuging and drying treatments.

[0016] The MoS2@Bi2S3∈HA bio-piezoelectric material prepared by the above preparation method.

[0017] The application of the above MoS2@Bi2S3∈HA bio-piezoelectric material as a class of antioxidant enzymes.

[0018] Furthermore, the antioxidant enzyme-like refers to catalase-like or glutathione reductase-like.

[0019] Application of the above-mentioned MoS2@Bi2S3∈HA biopiezoelectric material to enhance the activity of antioxidant enzyme-like under the action of ultrasound (US).

[0020] Application of the above-mentioned MoS2@Bi2S3∈HA biopiezoelectric material as a reactive oxygen scavenger.

[0021] Application of the above-mentioned MoS2@Bi2S3∈HA biopiezoelectric material as a piezoelectric catalyst in the production of hydrogen under the action of ultrasound.

[0022] Application of the above-mentioned MoS2@Bi2S3∈HA biopiezoelectric material in the preparation of drugs for treating inflammatory diseases. It exerts its effect through the following mechanism:

[0023] a. Under the action of ultrasound (0.1 - 2.5 W / cm 2 ), enhance the activity of antioxidant enzyme-like and scavenge reactive oxygen species in the inflammatory microenvironment;

[0024] b. Generate hydrogen through the piezoelectric effect and inhibit the release of inflammatory factors;

[0025] c. Provide electrical stimulation to promote cartilage repair.

[0026] Furthermore, the above-mentioned inflammatory diseases are inflammatory joint diseases such as rheumatoid arthritis, synovitis or osteoarthritis. It can be used by local injection, intra-articular administration or application.

[0027] Application of the above-mentioned MoS2@Bi2S3∈HA biopiezoelectric material in the preparation of drugs for cartilage repair.

[0028] The beneficial effects produced by the present invention are:

[0029] (1) For the MoS2@Bi2S3∈HA of the present invention, the doping of bismuth sulfide and molybdenum disulfide double metal sulfides improves the synergistic effect of ultrasonic piezoelectric hydrogen production and electrical stimulation, and significantly improves the anti-inflammatory efficiency in vivo and in vitro. To improve the biomedical application potential of MoS2@Bi2S3, hyaluronic acid is used to significantly improve its biological effect while not affecting the catalytic hydrogen production activity of MoS2@Bi2S3, and improve the water dispersion and biocompatibility of MoS2@Bi2S3, expand the biomedical application of MoS2@Bi2S3∈HA, and efficiently catalyze the treatment of inflammatory joint diseases with hydrogen production and electrical stimulation synergy.

[0030] (2) In terms of the preparation principle, the present application uses a two-step hydrothermal synthesis method to dissolve the metal precursor Bi(NO3)3·5H2O and PVP (Mw = 58000) in ethylene glycol. A mixture of Na2S·9H2O and ethylene glycol is added dropwise to the above solution, stirred in the dark at room temperature, transferred to a polytetrafluoroethylene high-pressure reaction kettle for hydrothermal reaction, centrifuged and washed to obtain Bi2S3 nanorods. Further, the obtained Bi2S3 nanorods are dispersed in deionized water, and Na2MoO4·2H2O and NH2CSNH2 are added in sequence, stirred in the dark at room temperature, transferred to a polytetrafluoroethylene high-pressure reaction kettle for hydrothermal reaction, centrifuged and washed to obtain the MoS2@Bi2S3 bimetallic sulfide. The MoS2@Bi2S3 is dispersed in a hyaluronic acid solution to obtain MoS2@Bi2S3∈HA.

[0031] (3) The present invention prepares MoS2@Bi2S3∈HA for the first time, which has good piezoelectric characteristics and electrical properties; in biomedical applications, it can effectively act on the joint inflammation microenvironment, and at the same time can achieve the catalytic treatment effect of in-situ high-efficiency catalytic production of H2 and electrical stimulation for inflammatory joint diseases under the action of ultrasound. The dispersion of MoS2@Bi2S3 in the hyaluronic acid solution can improve its biocompatibility and biosafety, and expand the application range of the MoS2@Bi2S3 bimetallic sulfide. Through the catalytic production of H2 and electrical stimulation in the inflammatory microenvironment by ultrasound, it has a strong inhibitory effect on inflammatory cells and a promoting effect on cartilage repair. At the same time, the viscoelasticity and biocompatibility of hyaluronic acid synergistically with the action of H2 and electrical stimulation can perform efficient anti-inflammatory and cartilage repair treatments, and have great application potential in the field of inflammatory joint disease treatment.

[0032] (4) The present invention uses MoS2@Bi2S3∈HA for ultrasonic hydrogen production and anti-inflammatory treatment. Utilizing the excellent piezoelectric properties and electrical characteristics of MoS2@Bi2S3, it has the characteristics of extremely low toxicity, high catalytic H2 production activity, and electrical stimulation to promote cartilage repair, and has the following advantages: First, hyaluronic acid can effectively improve the water dispersibility of the poorly soluble MoS2@Bi2S3 bimetallic sulfide, promote its dispersion and absorption in the biological water environment, and at the same time greatly improve biocompatibility, promoting the biomedical application of the bimetallic sulfide piezoelectric catalyst. Second, due to the doping of MoS2, the electron transfer efficiency in the piezoelectric effect at the microscopic geometric crystal interface is greatly improved, significantly increasing its catalytic activity for ultrasonic piezoelectric H2 production and electrical stimulation, and playing a low-toxic and high-efficiency treatment effect in the anti-inflammatory catalytic treatment of inflammatory joint diseases. In addition, hyaluronic acid can increase the viscoelasticity of synovial fluid, reduce the surface friction of cartilage, and reduce the damage of cartilage and bone tissues. Brief Description of the Drawings

[0033] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0034] Figure 1 HRTEM image of MoS2@Bi2S3 prepared in Example 1 of the present invention.

[0035] Figure 2 XRD pattern of MoS2@Bi2S3 prepared in Example 1 of the present invention, where (A) is the XRD pattern of MoS2@Bi2S3, and (B) is the locally enlarged XRD pattern.

[0036] Figure 3 EDS elemental distribution map of MoS2@Bi2S3 prepared in Example 1 of the present invention.

[0037] Figure 4 ICP-OES quantitative analysis of the contents of Bi, Mo, and S in MoS2@Bi2S3 with different doping ratios.

[0038] Figure 5 PFM amplitude butterfly loop diagrams (A, B) of Bi2S3 and MoS2@Bi2S3; piezoelectric response phase lag loop diagrams (C, D) of Bi2S3 and MoS2@Bi2S3; PFM surface potential 3D images (E, F) of Bi2S3 and MoS2@Bi2S3.

[0039] Figure 6 UPS ultraviolet photoelectron spectroscopy diagrams of Bi2S3, MoS2, and MoS2@Bi2S3.

[0040] Figure 7 Mott-Schottky (M-S) curve diagrams (A, B) and band gap diagrams (C, D) of Bi2S3 and MoS2@Bi2S3.

[0041] Figure 8 EIS Nyquist Plot diagrams (A) and LSV curve diagrams (B) of Bi2S3 and MoS2@Bi2S3.

[0042] Figure 9Hydrogen production diagrams under different conditions, where (A) is the hydrogen production diagram of MoS2@Bi2S3 with different doping ratios; (B) is the hydrogen production diagram of different materials Bi2S3, MoS2, and MoS2@Bi2S3; (C) is the hydrogen production diagram of MoS2@Bi2S3 under different ultrasonic power; (D) is the hydrogen production diagram of MoS2@Bi2S3 under different ultrasonic action times; (E) is the hydrogen production diagram of MoS2@Bi2S3 with different concentrations.

[0043] Figure 10 Diagram of the effect of HA on hydrogen production of MoS2@Bi2S3.

[0044] Figure 11 Diagram of the enhancement of piezoelectric effect on antioxidant enzyme-like activity; where (A) is the effect of scavenging ·OH under different ultrasonic powers, (B) is the ability of different concentrations of MoS2@Bi2S3 to scavenge ·OH and (C) to degrade H2O2, and (D) is the effect of pH on the degradation of H2O2 by MoS2@Bi2S3.

[0045] Figure 12 Diagram of the hemolytic property investigation of MoS2@Bi2S3 and MoS2@Bi2S3∈HA prepared in Example 1.

[0046] Figure 13 Statistical analysis of the activities of RAW264.7 and ADSCs cells, where (A) is the cell activity diagram of RAW264.7 cells under different ultrasonic powers; (B) is the cell activity diagram of ADSCs cells under 0.5 W / cm 2 , 8-minute ultrasonic action.

[0047] Figure 14 Diagram of the ROS content in RAW264.7 cells.

[0048] Figure 15 Diagram of the inhibitory effect of MoS2@Bi2S3∈HA on the expression levels of inflammatory factors produced by RAW264.7 cells, where (A) is TNF-α; (B) is IL-6; (C) is IL-1β.

[0049] Figure 16 Diagram of the promotion of TGF-β1 secretion by (A) RAW264.7 cells and (B) ADSCs cells by the electrical stimulation generated by MoS2@Bi2S3∈HA under ultrasonic treatment.

[0050] Figure 17 Diagram of (A) arthritis score and (B) paw thickness.

[0051] Figure 18 Diagram of joint (A) H&E staining, (B) Safranin O, and (C) Masson staining. Detailed implementation manners

[0052] Next, in combination with the embodiments of the present invention, the technical solutions of the present invention will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0053] Example 1

[0054] The preparation method of the MoS2@Bi2S3∈HA biological piezoelectric material in this embodiment is as follows:

[0055] 1. The preparation method of MoS2@Bi2S3 is as follows:

[0056] (1) Preparation of Bi2S3 nanorods:

[0057] ① Weigh 0.498 g of Bi(NO3)3·5H2O and add it to 70 mL of ethylene glycol. Avoid light and stir magnetically at room temperature for 30 minutes, with a rotation speed of about 750 r / min.

[0058] ② Add 0.5 g of PVP (Mw = 58000), and continue to stir magnetically at room temperature in the dark for 30 minutes, with a rotation speed of about 750 r / min.

[0059] ③ Using ethylene glycol as the solvent, prepare a 2 mL 180 mg / mL Na2S·9H2O solution and drop it into the above-mentioned mixture.

[0060] ④ Transfer the solution to a reaction kettle lined with polytetrafluoroethylene, place it in a drying oven, and heat it at 180 °C for 4 hours.

[0061] ⑤ Cool to room temperature, centrifuge at 12000 r / min at 25 °C for 15 minutes; then centrifuge with absolute ethanol and deionized water at 12000 r / min at 25 °C for 10 minutes each, and centrifuge 3 times.

[0062] ⑥ Place the centrifuged precipitate in a vacuum drying oven at 70 °C and dry it overnight to obtain: Bi2S3 nanorods.

[0063] (2) Preparation of MoS2@Bi2S3 hybrid bimetallic sulfide biological piezoelectric material:

[0064] ① Weigh 500 mg of Bi2S3 nanorods, add 30 mL of ultrapure water, stir magnetically in the dark at room temperature, with a rotation speed of about 850 r / min, and ultrasonically shake to disperse it completely.

[0065] ② Calculate according to 20% of the amount of substance of Bi2S3 nanorods, add Na2MoO4·2H2O, avoid light, and stir magnetically at room temperature for 6 hours at a rotation speed of about 850 r / min.

[0066] ③ Add NH2CSNH2 according to 5 times the mass of the added Na2MoO4·2H2O, continue to avoid light, and stir magnetically at room temperature for 1 hour at a rotation speed of about 850 r / min.

[0067] ④ Transfer the solution to a reaction kettle lined with polytetrafluoroethylene, place it in a drying oven, and heat at 220 °C for 24 hours.

[0068] ⑤ Cool to room temperature, centrifuge at 12000 r / min at 25 °C for 15 minutes; then centrifuge with deionized water and absolute ethanol respectively at 12000 r / min at 25 °C for 10 minutes, and centrifuge 3 times each.

[0069] ⑥ Precipitate the centrifuged product, vacuum dry at 60 °C overnight to obtain MoS2@Bi2S3.

[0070] 2. Preparation of MoS2@Bi2S3∈HA: Prepare a hyaluronic acid solution. Take a certain amount of hyaluronic acid with a molecular weight of 2.5×10 6 Da and disperse it in deionized water. After ultrasonic dispersion for 2 hours and swelling at 4 °C for 24 hours, a hyaluronic acid solution with a concentration of 2 mg / mL is obtained. Mix MoS2@Bi2S3 and hyaluronic acid evenly according to a mass ratio of 1:10, and mix it with the hybrid bimetallic sulfide biopiezoelectric material of MoS2@Bi2S3 prepared in this example. Stir at room temperature for 2 hours to obtain a MoS2@Bi2S3∈HA solution with a concentration of 200 μg / mL, that is, MoS2@Bi2S3∈HA.

[0071] Example 2

[0072] The preparation method of the MoS2@Bi2S3∈HA biopiezoelectric material in this example is as follows:

[0073] 1. The preparation method of MoS2@Bi2S3 is as follows:

[0074] (1) Preparation of Bi2S3 nanorods:

[0075] ① Weigh 0.498 g of Bi(NO3)3·5H2O and add it to 70 mL of ethylene glycol. Avoid light and stir magnetically at room temperature for 30 minutes at a rotation speed of about 750 r / min.

[0076] ② Add 0.5 g of PVP (Mw = 58000), continue to avoid light and stir magnetically at room temperature for 30 minutes at a rotation speed of about 750 r / min.

[0077] ③ Using ethylene glycol as a solvent, prepare a 2 mL solution of 180 mg / mL Na2S·9H2O and add it dropwise to the above-mentioned mixture.

[0078] ④ Transfer the solution to a reaction kettle with a polytetrafluoroethylene inner lining, place it in a drying oven, and heat it at 180 °C for 4 hours.

[0079] ⑤ Cool to room temperature, centrifuge at 12000 r / min at 25 °C for 15 minutes; then centrifuge with absolute ethanol and deionized water respectively at 12000 r / min at 25 °C for 10 minutes, and centrifuge 3 times each.

[0080] ⑥ Place the centrifuged precipitate in a vacuum drying oven at 70 °C and dry it overnight to obtain: Bi2S3 nanorods.

[0081] (2) Preparation of MoS2@Bi2S3 hybrid bimetallic sulfide biopiezoelectric material:

[0082] ① Weigh 500 mg of Bi2S3 nanorods, add 30 mL of ultrapure water, stir magnetically in the dark at room temperature at a rotation speed of about 850 r / min, and ultrasonically shake to make it completely dispersed.

[0083] ② Calculate according to 15% of the amount of substance of Bi2S3 nanorods, add Na2MoO4·2H2O, stir magnetically in the dark at room temperature for 6 hours at a rotation speed of about 850 r / min.

[0084] ③ Add NH2CSNH2 according to 5 times the mass of Na2MoO4·2H2O added, continue to stir magnetically in the dark at room temperature for 1 hour at a rotation speed of about 850 r / min.

[0085] ④ Transfer the solution to a reaction kettle with a polytetrafluoroethylene inner lining, place it in a drying oven, and heat it at 220 °C for 24 hours.

[0086] ⑤ Cool to room temperature, centrifuge at 12000 r / min at 25 °C for 15 minutes; then centrifuge with deionized water and absolute ethanol respectively at 12000 r / min at 25 °C for 10 minutes, and centrifuge 3 times each.

[0087] ⑥ Vacuum dry the centrifuged product precipitate overnight at 60 °C to obtain MoS2@Bi2S3.

[0088] 2. Preparation of MoS2@Bi2S3∈HA: Prepare a hyaluronic acid solution, take a certain amount with a molecular weight of 2.5×10 6Hyaluronic acid of Da was dispersed in ultrapure water. After ultrasonic dispersion for 2 hours and swelling at 4°C for 24 hours, a hyaluronic acid solution with a concentration of 2 mg / mL was obtained. MoS2@Bi2S3 and hyaluronic acid were mixed evenly according to a mass ratio of 1:2, and were mixed with the MoS2@Bi2S3 hybrid bimetallic sulfide biopiezoelectric material prepared in this example. After stirring at room temperature for 2 hours, a MoS2@Bi2S3∈HA solution with a concentration of 1000 μg / mL was obtained, namely MoS2@Bi2S3∈HA.

[0089] Example 3

[0090] The preparation method of the MoS2@Bi2S3∈HA biopiezoelectric material in this example is as follows:

[0091] 1. The preparation method of MoS2@Bi2S3 is as follows:

[0092] (1) Preparation of Bi2S3 nanorods:

[0093] ① Weigh 0.498 g of Bi(NO3)3·5H2O and add it to 70 mL of ethylene glycol. Avoid light and stir magnetically at room temperature for 30 minutes, with a rotation speed of about 750 r / min.

[0094] ② Add 0.5 g of PVP (Mw = 58000), and continue to stir magnetically at room temperature in the dark for 30 minutes, with a rotation speed of about 750 r / min.

[0095] ③ Using ethylene glycol as a solvent, prepare a 2 mL 180 mg / mL Na2S·9H2O solution, and drip it into the above mixture.

[0096] ④ Transfer the solution to a reaction kettle with a polytetrafluoroethylene inner lining, place it in a drying oven, and heat at 180°C for 4 hours.

[0097] ⑤ Cool to room temperature, centrifuge at 12000 r / min for 15 minutes at 25°C; then centrifuge with absolute ethanol and deionized water at 12000 r / min for 10 minutes at 25°C respectively, and centrifuge 3 times each.

[0098] ⑥ Place the centrifuged precipitate in a vacuum drying oven at 70°C and dry overnight to obtain: Bi2S3 nanorods.

[0099] (2) Preparation of MoS2@Bi2S3 hybrid bimetallic sulfide biopiezoelectric material:

[0100] ① Weigh 500 mg of Bi2S3 nanorods, add 30 mL of ultrapure water, stir magnetically in the dark at room temperature, with a rotation speed of about 850 r / min, and ultrasonically shake to completely disperse it.

[0101] ② Calculate according to 10% of the amount of substance of Bi2S3 nanorods, add Na2MoO4·2H2O, keep it away from light, and stir magnetically at room temperature for 6 hours with a rotation speed of about 850 r / min.

[0102] ③ Add NH2CSNH2 according to 5 times the mass of the added Na2MoO4·2H2O, continue to keep it away from light, and stir magnetically at room temperature for 1 hour with a rotation speed of about 850 r / min.

[0103] ④ Transfer the solution to a reaction kettle lined with polytetrafluoroethylene, place it in an oven, and heat at 220 °C for 24 hours.

[0104] ⑤ Cool to room temperature, centrifuge at 12000 r / min at 25 °C for 15 minutes; then centrifuge with deionized water and absolute ethanol respectively at 12000 r / min at 25 °C for 10 minutes, and centrifuge 3 times each.

[0105] ⑥ Precipitate the centrifuged product, dry it in vacuum at 60 °C overnight to obtain MoS2@Bi2S3.

[0106] 2. Preparation of MoS2@Bi2S3∈HA: Prepare a hyaluronic acid solution. Take a certain amount of hyaluronic acid with a molecular weight of 2.5×10 6 Da and disperse it in ultrapure water. After ultrasonic dispersion for 2 hours and swelling at 4 °C for 24 hours, a hyaluronic acid solution with a concentration of 2 mg / mL is obtained. Mix MoS2@Bi2S3 and hyaluronic acid according to a mass ratio of 1:2, and mix them evenly with the MoS2@Bi2S3 hybrid bimetallic sulfide biopiezoelectric material prepared in this example. Stir at room temperature for 2 hours to obtain a MoS2@Bi2S3∈HA solution with a concentration of 1000 μg / mL, that is, MoS2@Bi2S3∈HA.

[0107] Example 4

[0108] The preparation method of the MoS2@Bi2S3∈HA biopiezoelectric material in this example is as follows:

[0109] 1. The preparation method of MoS2@Bi2S3 is as follows:

[0110] (1) Preparation of Bi2S3 nanorods:

[0111] ① Weigh 0.498 g of Bi(NO3)3·5H2O and add it to 70 mL of ethylene glycol. Keep it away from light and stir magnetically at room temperature for 30 minutes with a rotation speed of about 750 r / min.

[0112] ② Add 0.5 g of PVP (Mw = 58000), continue to keep it away from light and stir magnetically at room temperature for 30 minutes with a rotation speed of about 750 r / min.

[0113] ③ Using ethylene glycol as the solvent, prepare a 2 mL solution of 180 mg / mL Na2S·9H2O and add it dropwise to the above-mentioned mixture.

[0114] ④ Transfer the solution to a reaction kettle with a polytetrafluoroethylene liner, place it in a drying oven, and heat at 180 °C for 2 hours.

[0115] ⑤ Cool to room temperature, centrifuge at 12000 r / min at 25 °C for 15 minutes; then centrifuge with absolute ethanol and deionized water respectively at 12000 r / min at 25 °C for 10 minutes, and centrifuge 3 times each.

[0116] ⑥ Place the centrifuged precipitate in a vacuum drying oven at 70 °C and dry overnight to obtain: Bi2S3 nanorods.

[0117] (2) Preparation of MoS2@Bi2S3 hybrid bimetallic sulfide biopiezoelectric material:

[0118] ① Weigh 500 mg of Bi2S3 nanorods, add 30 mL of deionized water, stir magnetically in the dark at room temperature at a rotation speed of about 850 r / min, and ultrasonically shake to completely disperse them.

[0119] ② Calculate according to 25% of the amount of substance of Bi2S3 nanorods, add Na2MoO4·2H2O, stir magnetically in the dark at room temperature for 6 hours at a rotation speed of about 850 r / min.

[0120] ③ Add NH2CSNH2 according to 5 times the mass of Na2MoO4·2H2O added, continue to stir magnetically in the dark at room temperature for 1 hour at a rotation speed of about 850 r / min.

[0121] ④ Transfer the solution to a reaction kettle with a polytetrafluoroethylene liner, place it in a drying oven, and heat at 240 °C for 20 hours.

[0122] ⑤ Cool to room temperature, centrifuge at 12000 r / min at 25 °C for 15 minutes; then centrifuge with deionized water and absolute ethanol respectively at 12000 r / min at 25 °C for 10 minutes, and centrifuge 3 times each.

[0123] ⑥ Vacuum-dry the centrifuged product precipitate overnight at 60 °C to obtain MoS2@Bi2S3.

[0124] 2. Preparation of MoS2@Bi2S3∈HA: Prepare a hyaluronic acid solution, take a certain amount with a molecular weight of 2.5×10 6Hyaluronic acid with a molecular weight of

[0125] Example 5

[0126] The preparation method of the MoS2@Bi2S3∈HA biopiezoelectric material in this example is as follows:

[0127] 1. The preparation method of MoS2@Bi2S3 is the same as that in Example 1.

[0128] 2. Preparation of MoS2@Bi2S3∈HA: Prepare a hyaluronic acid solution. Take different masses of hyaluronic acid with a molecular weight of 2.5×10 6 Da and disperse it in deionized water. After ultrasonic dispersion for 2 hours and swelling at 4°C for 24 hours, a hyaluronic acid solution with a concentration of 2 mg / mL is obtained. According to the mass ratios of MoS2@Bi2S3 to hyaluronic acid of 1:0.5, 1:1, and 1:2 respectively, mix it evenly with the MoS2@Bi2S3 hybrid bimetallic sulfide biopiezoelectric material prepared in this example, and stir at room temperature for 2 hours to obtain MoS2@Bi2S3∈HA.

[0129] Example 6

[0130] The preparation method of the MoS2@Bi2S3∈HA biopiezoelectric material in this example is as follows:

[0131] 1. The preparation method of MoS2@Bi2S3 is the same as that in Example 1.

[0132] 2. Preparation of MoS2@Bi2S3∈HA: Prepare a hyaluronic acid solution. Take different masses of hyaluronic acid with a molecular weight of 1.5×10 6 Da and disperse it in deionized water. After ultrasonic dispersion for 2 hours and swelling at 4°C for 24 hours, a hyaluronic acid solution with a concentration of 2 mg / mL is obtained. According to the mass ratios of MoS2@Bi2S3 to hyaluronic acid of 1:0.5, 1:1, and 1:2 respectively, mix it evenly with the MoS2@Bi2S3 hybrid bimetallic sulfide biopiezoelectric material prepared in this example, and stir at room temperature for 2 hours to obtain MoS2@Bi2S3∈HA.

[0133] Example 7

[0134] The preparation method of the MoS2@Bi2S3∈HA biological piezoelectric material in this embodiment is as follows:

[0135] 1. The preparation method of MoS2@Bi2S3 is the same as that in Example 1.

[0136] 2. Preparation of MoS2@Bi2S3∈HA: Prepare a hyaluronic acid solution. Take a certain amount of hyaluronic acid with a molecular weight of 2.5×10 6 Da and disperse it in deionized water. After ultrasonic dispersion for 2 hours and swelling at 4°C for 24 hours, a hyaluronic acid solution with a concentration of 2 mg / mL is obtained. According to the mass ratios of MoS2@Bi2S3 to hyaluronic acid of 1:10, 1:20, 1:40, and 1:80 respectively, mix them evenly with the hybrid bimetallic sulfide biological piezoelectric material of MoS2@Bi2S3 prepared in this embodiment, and stir at room temperature for 2 hours to obtain MoS2@Bi2S3∈HA solutions with concentrations of 200 μg / mL, 100 μg / mL, 50 μg / mL, and 25 μg / mL respectively, that is, MoS2@Bi2S3∈HA.

[0137] Example 8

[0138] The preparation method of the MoS2@Bi2S3∈HA biological piezoelectric material in this embodiment is as follows:

[0139] 1. The preparation method of MoS2@Bi2S3 is as follows:

[0140] (1) Preparation of Bi2S3 nanorods:

[0141] ① Weigh 0.498 g of Bi(NO3)3·5H2O and add it to 70 mL of ethylene glycol. Avoid light and stir magnetically at room temperature for 30 minutes with a rotation speed of about 750 r / min.

[0142] ② Add 0.5 g of PVP (Mw = 58000), and continue to stir magnetically at room temperature in the dark for 30 minutes with a rotation speed of about 750 r / min.

[0143] ③ Using ethylene glycol as the solvent, prepare a 2 mL 180 mg / mL Na2S·9H2O solution and drop it into the above mixture.

[0144] ④ Transfer the solution to a reaction kettle with a polytetrafluoroethylene inner lining, put it into a drying oven, and heat at 160°C for 5 hours.

[0145] ⑤ Cool to room temperature, centrifuge at 12000 r / min at 25°C for 15 minutes; then centrifuge with absolute ethanol and deionized water at 12000 r / min at 25°C for 10 minutes respectively, and centrifuge 3 times each.

[0146] ⑥ The centrifuged precipitate was placed in a vacuum drying oven at 70 °C and dried overnight to obtain Bi2S3 nanorods.

[0147] (2) Preparation of MoS2@Bi2S3 hybrid bimetallic sulfide biopiezoelectric material:

[0148] ① Weigh 500 mg of Bi2S3 nanorods, add 30 mL of ultrapure water, and stir magnetically in the dark at room temperature at a rotation speed of about 850 r / min, and ultrasonically shake to completely disperse it.

[0149] ② Calculate according to 20% of the amount of substance of Bi2S3 nanorods, add Na2MoO4·2H2O, stir magnetically in the dark at room temperature for 6 hours at a rotation speed of about 850 r / min.

[0150] ③ Add NH2CSNH2 according to 5 times the mass of the added Na2MoO4·2H2O, continue to stir magnetically in the dark at room temperature for 1 hour at a rotation speed of about 850 r / min.

[0151] ④ Transfer the solution to a reaction kettle lined with polytetrafluoroethylene, place it in a drying oven, and heat at 240 °C for 20 hours.

[0152] ⑤ Cool to room temperature, centrifuge at 12000 r / min at 25 °C for 15 minutes; then centrifuge with deionized water and absolute ethanol at 12000 r / min at 25 °C for 10 minutes each, and centrifuge 3 times.

[0153] ⑥ Vacuum dry the centrifuged product precipitate overnight at 60 °C to obtain MoS2@Bi2S3.

[0154] 2. Preparation of MoS2@Bi2S3∈HA: Prepare a hyaluronic acid solution. Take a certain amount of hyaluronic acid with a molecular weight of 2.5×10 6 Da and disperse it in deionized water. After ultrasonic dispersion for 2 hours and swelling at 4 °C for 24 hours, a hyaluronic acid solution with a concentration of 3 mg / mL is obtained. MoS2@Bi2S3 and hyaluronic acid are mixed evenly according to a mass ratio of 1:3 and mixed with the MoS2@Bi2S3 hybrid bimetallic sulfide biopiezoelectric material prepared in this example, and stirred at room temperature for 2 hours to obtain MoS2@Bi2S3∈HA.

[0155] Example 9

[0156] The preparation method of the MoS2@Bi2S3∈HA biopiezoelectric material in this example is as follows:

[0157] 1. The preparation method of MoS2@Bi2S3 is as follows:

[0158] (1) Preparation of Bi2S3 nanorods:

[0159] ① Weigh 0.498 g of Bi(NO3)3·5H2O and add it to 70 mL of ethylene glycol. Avoid light and stir magnetically at room temperature for 30 minutes at a rotation speed of about 750 r / min.

[0160] ② Add 0.5 g of PVP (Mw = 58000), and continue to stir magnetically at room temperature in the dark for 30 minutes at a rotation speed of about 750 r / min.

[0161] ③ Using ethylene glycol as the solvent, prepare a 2 mL solution of 180 mg / mL Na2S·9H2O and add it dropwise to the above-mentioned mixture.

[0162] ④ Transfer the solution to a reaction kettle lined with polytetrafluoroethylene, place it in an oven, and heat at 160 °C for 2 hours.

[0163] ⑤ Cool to room temperature, centrifuge at 12000 r / min at 25 °C for 15 minutes; then centrifuge with absolute ethanol and deionized water respectively at 12000 r / min at 25 °C for 10 minutes, and centrifuge 3 times each.

[0164] ⑥ Place the centrifuged precipitate in a vacuum drying oven at 70 °C and dry overnight to obtain: Bi2S3 nanorods.

[0165] (2) Preparation of MoS2@Bi2S3 hybrid bimetallic sulfide biopiezoelectric material:

[0166] ① Weigh 500 mg of Bi2S3 nanorods, add 30 mL of ultrapure water, stir magnetically in the dark at room temperature at a rotation speed of about 850 r / min, and ultrasonically shake to make it completely dispersed.

[0167] ② Calculate according to 20% of the amount of substance of Bi2S3 nanorods, add Na2MoO4·2H2O, avoid light, and stir magnetically at room temperature for 6 hours at a rotation speed of about 850 r / min.

[0168] ③ Add NH2CSNH2 according to 5 times the mass of the added Na2MoO4·2H2O, continue to avoid light, and stir magnetically at room temperature for 1 hour at a rotation speed of about 850 r / min.

[0169] ④ Transfer the solution to a reaction kettle lined with polytetrafluoroethylene, place it in an oven, and heat at 200 °C for 28 hours.

[0170] ⑤ Cool to room temperature, centrifuge at 12000 r / min at 25 °C for 15 minutes; then centrifuge with deionized water and absolute ethanol respectively at 12000 r / min at 25 °C for 10 minutes, and centrifuge 3 times each.

[0171] ⑥ Place the centrifuged product precipitate in a vacuum at 60 °C and dry overnight to obtain MoS2@Bi2S3.

[0172] 2. Preparation of MoS2@Bi2S3∈HA: Prepare hyaluronic acid solution and take a certain amount of molecular weight of 2.5×10 6 Da of hyaluronic acid was dispersed in deionized water, ultrasonically dispersed for 2 hours, and swollen at 4°C for 24 hours to obtain a hyaluronic acid solution with a concentration of 0.25 mg / mL. MoS2@Bi2S3 and hyaluronic acid were mixed evenly with the MoS2@Bi2S3 hybrid bimetallic sulfide biopiezoelectric material prepared in this embodiment at a mass ratio of 1:2, and stirred at room temperature for 2 hours to obtain MoS2@Bi2S3∈HA.

[0173] Comparative Example 1

[0174] This comparative example is a method for preparing MoS2, and the steps are as follows:

[0175] ① Add 24 mg Na2MoO4·2H2O to 15 mL deionized water, protect from light, and stir magnetically at room temperature for 2 hours. Add NH2CSNH2 at a rate of 5 times the mass of Na2MoO4·2H2O, continue to protect from light, and stir magnetically at room temperature for 2 hours at a speed of about 850 r / min.

[0176] ② Transfer the solution to a polytetrafluoroethylene-lined reactor and place it in a drying oven at 220°C for 24 hours.

[0177] ③ Cool to room temperature, centrifuge at 12000r / min, 25℃ for 15 minutes; then centrifuge with deionized water and anhydrous ethanol at 12000r / min, 25℃ for 10 minutes, each centrifuge 3 times.

[0178] ④ Precipitate the product after centrifugation and dry it in vacuum at 60°C overnight to obtain MoS2.

[0179] Test Case

[0180] 1. Microscopic morphology characterization

[0181] (1) High-resolution transmission electron microscopy (HRTEM) characterization

[0182] The MoS2@Bi2S3 bimetallic sulfide biopiezoelectric material prepared in Example 1 was dispersed in a C2H5OH solution and fully ultrasonically vibrated to make it evenly dispersed. 10 μL was taken with a pipette and dropped onto a 300-mesh microgrid copper mesh, and repeated 3 times. The obtained copper mesh sample was placed under HRTEM for morphological observation. The results are shown in Figure 2. Figure 1 As shown in A, Bi2S3 presents a rod-like structure, and after being doped with MoS2, a hybrid layer is formed on the outside. Figure 1As can be seen from the B-C results, compared with the tetragonal Bi2S3 (PDF#17-0320), the (220), (130), and (101) crystal planes of Bi2S3 in the sample can be clearly observed; compared with the hexagonal 3R-MoS2 (PDF#17-0744), the (006), (003), and (015) crystal planes of MoS2 in the doped sample can be clearly seen. This proves the successful preparation and doping of the MoS2@Bi2S3 bimetallic sulfide biopiezoelectric material.

[0183] (2) X-ray powder diffraction (XRD)

[0184] The powder sample was pressed into a tablet to make its surface smooth and flat. A CT tomographic X-ray diffraction system was used to measure and analyze the sample structure. The radiation source was Cu Kα, the scanning range was set from 5° to 90°, and the scanning speed was set at 5° / min.

[0185] The results are as Figure 2 shown in Figure A. The sample has sharp diffraction peaks, indicating that MoS2@Bi2S3 has a good crystal structure. After analysis, the diffraction peaks of MoS2@Bi2S3 can be attributed to the tetragonal Bi2S3 (PDF#17-0320) and the hexagonal 3R-MoS2 (PDF#17-0744). Some diffraction peaks can be attributed to the (101), (130), (211), (221) crystal planes of Bi2S3 and the (101), (012) crystal planes of MoS2, etc.; compared with Bi2S3 (PDF#17-0320), the diffraction peaks of Bi2S3 in MoS2@Bi2S3 shift slightly to the right ( Figure 2 Figure B), indicating that the lattice constant of the sample becomes smaller, which again indicates the successful doping of MoS2.

[0186] 2. Element content analysis

[0187] Energy dispersive X-ray spectroscopy (EDS) and inductively coupled plasma optical emission spectrometry (ICP-OES) were used to qualitatively and quantitatively analyze the elemental composition of MoS2@Bi2S3, respectively.

[0188] The results are as Figure 3 shown. MoS2@Bi2S3 contains three elements, Bi, Mo, and S, and the three elements are evenly distributed, which preliminarily proves the successful preparation of Bi2S3 and the successful doping of MoS2.

[0189] The ICP-OES content analysis results of MoS2@Bi2S3 prepared in Examples 1, 2, and 4 are as Figure 4As shown, with the increase in the doping ratio of MoS2, the elemental content ratios of Mo and S relative to the overall material increase, further proving the successful doping of MoS2@Bi2S3, which is in line with the feeding design of different ratios of Mo sources and S sources in the preparation method.

[0190] 3. Piezoelectric Property Characterization

[0191] To clarify the effect of MoS2 doping on piezoelectric properties, piezoresponse force microscopy (PFM) was used to analyze the MoS2@Bi2S3 prepared in Example 1. When measuring the piezoelectric response of PFM, a sweep bias voltage of -10 to 10 V is required for pure Bi2S3, while for MoS2@Bi2S3, a sweep bias voltage of only -3 to 3 V is needed to obtain a more significant and typical butterfly loop ( Figure 5 Figures 5A and 5B), and a piezoelectric response phase lag loop of ≈180° ( Figure 5 Figures 5C and 5D), indicating that MoS2 doping can significantly improve the piezoelectric properties of the product. As shown in Figure 5 Figure 5E, under the stress of the probe tip, an internal electric field can be formed in Bi2S3, generating a surface voltage of 38.3 mV. After doping, the surface voltage of MoS2@Bi2S3 can reach 118.6 mV ( Figure 5 Figure 5F), indicating that MoS2 doping can significantly improve the piezoelectric response of MoS2@Bi2S3. To quantitatively obtain the piezoelectric strength, the maximum effective piezoelectric coefficient d is calculated according to the slope of the amplitude loop. 33 It can be known that the d 33 values of Bi2S3 and MoS2@Bi2S3 are 31.78 and 72.30 pm / V, respectively.

[0192] 4. Electrical Property Characterization

[0193] To clarify the effect of MoS2 doping on electrical properties, first, ultraviolet photoelectron spectroscopy (UPS) was used to analyze the valence electron spectra of Bi2S3 and MoS2@Bi2S3 prepared in Example 1 and MoS2 prepared in Comparative Example 1. As shown in Figure 6 Figures 6A - 6C, the work functions of Bi2S3, MoS2, and MoS2@Bi2S3 are 2.79 eV, 4.59 eV, and 4.11 eV, respectively. For materials with a larger Fermi level, the work function is smaller. Since the Fermi levels of the two materials are different, electron redistribution will inevitably occur during contact doping, and electrons flow from the material with a smaller work function to the material with a larger work function. It can be seen that when MoS2 is doped, electrons flow from Bi2S3 to MoS2, promoting electron transfer, laying a foundation for subsequent efficient H2 production and electrical stimulation.

[0194] Then, the Mott - Schottky (M - S) of the electrochemical workstation was used to measure the semiconductor electrochemical properties of the product. As shown in Figure 7As shown in A-B, the slope of the M-S curve of the sample is positive, indicating that the products before and after MoS2 doping are both n-type semiconductors. From the data obtained by the tangent of the M-S spectrum, the flat band potentials (F fb ) of Bi2S3 and MoS2@Bi2S3 are -0.75 V and -1.17 V (vs Ag / AgCl, pH = 7), respectively. For the hydrogen electrode (NHE), the F fb of Bi2S3 and MoS2@Bi2S3 are -0.55 V and -0.97 V (vs NHE, pH = 7). Since the F fb of n-type semiconductors can be converted to their conduction band potentials (C B ), the C B of Bi2S3 and MoS2@Bi2S3 are -0.55 V and -0.97 V (vs NHE, pH = 7), respectively. The band gap energies (E g ) of Bi2S3 and MoS2@Bi2S3 can be obtained by using ultraviolet-visible diffuse reflectance spectroscopy (UV-vis DRS). As shown in Figure 7 C-D, the E g of Bi2S3 and MoS2@Bi2S3 are 1.20 eV and 1.16 eV, respectively. According to the formula E g = E VB - E CB , combined with the M-S values, the valence band potentials (V B ) of Bi2S3 and MoS2@Bi2S3 are 0.65 V and 0.19 V (vs NHE, pH = 7), respectively. The results show that MoS2@Bi2S3 obtained by MoS2 doping has a more negative conduction band potential and a more positive valence band potential, significantly improving the charge separation efficiency between the conduction and valence bands compared with Bi2S3 alone, and promoting sustainable H2 generation.

[0195] To investigate the electro-stimulus characteristics of MoS2@Bi2S3, an electrochemical workstation was used to further measure the electrochemical impedance spectrum (EIS) and linear sweep voltammetry (LSV) of the product. EIS measures the change of impedance with the sine wave frequency to evaluate the electron transfer ability of the sample. As shown in the Figure 8 Nyquist plot in A, the arc radius of the high-frequency region on the left side of MoS2@Bi2S3 is smaller than that of Bi2S3, indicating that the charge transfer impedance of the sample decreases after MoS2 doping, its current increases, and the electron transfer ability at the MoS2@Bi2S3 interface is more significant, promoting the piezoelectric catalytic hydrogen evolution reaction. As shown in Figure 8 B, a linearly changing voltage is applied to the working electrode. As the linear sweep voltage progresses, MoS2@Bi2S3 has a more significant upward trend of the electrode current compared with Bi2S3, which is more conducive to promoting the generation of H2.

[0196] 5. H₂ Production Performance Study

[0197] The amount of H₂ produced by the sample solution was quantitatively detected using a gas chromatograph (GC). The specific operation steps are as follows:

[0198] (1) Hydrogen production of different preparations:

[0199] 1) Weigh 10 mg of MoS₂@Bi₂S₃ prepared in Example 1, Bi₂S₃, and MoS₂ of Comparative Example 1 and place them in a 20 mL headspace vial. Dissolve them in 10 mL of deionized water to prepare a sample solution with a concentration of 1 mg / mL.

[0200] 2) After the sample solution is fully dispersed and homogenized, nitrogen is filled at a flow rate of 5 mL / min for 15 minutes to exclude the interference of other impurity gases such as H₂ in the water.

[0201] 3) After exhausting the gas, seal the mouth of the headspace vial and sonicate it with a sonicator (2.5 W / cm 2 , 30 minutes).

[0202] 4) Take 1 mL of gas from the headspace vial with a syringe and detect the hydrogen production of the sample by GC.

[0203] (2) Hydrogen production of MoS₂@Bi₂S₃ with different doping ratios (MoS₂) prepared in Examples 1, 2, and 4: Weigh 10 mg of MoS₂@Bi₂S₃ with doping ratios (MoS₂) of 15%, 20%, and 25% (mole percentage) respectively and place them in a 20 mL headspace vial. Disperse them in 10 mL of deionized water to prepare a sample with a concentration of 1 mg / mL. The subsequent operations are the same as above.

[0204] (3) Hydrogen production of MoS₂@Bi₂S₃ with different concentrations: Weigh a certain amount of MoS₂@Bi₂S₃ prepared in Example 1 and place it in a 20 mL headspace vial. Disperse it in 10 mL of deionized water to prepare MoS₂@Bi₂S₃ solutions with concentrations of 2, 1, 0.5, 0.25, and 0.1 mg / mL respectively. The subsequent operations are the same as above.

[0205] (4) Hydrogen production of MoS₂@Bi₂S₃ prepared in Example 1 under different sonication times: The operation is similar to the above, only the sonication time is set to 60, 30, 20, 10, 5, and 3 minutes.

[0206] (5) Hydrogen production of MoS₂@Bi₂S₃ prepared in Example 1 under different sonication powers: The operation is similar to the above, only the sonication power is set to 0.5, 1.5, and 2.5 W / cm 2 .

[0207] (6) Influence of HA-modified MoS2@Bi2S3 (MoS2@Bi2S3∈HA) prepared in Example 5 and Example 6 on hydrogen production: The operation was similar to the above. Weigh 10 mL of the series of solutions prepared in Example 5 and Example 6 respectively for testing.

[0208] The piezoelectric catalytic H2 production efficiency of MoS2@Bi2S3 is closely related to the ultrasonic time and power, and has concentration dependence. Prolonging the ultrasonic time, increasing the ultrasonic power, increasing the concentration of MoS2@Bi2S3, and HA modification (MoS2@Bi2S3∈HA) can all increase the hydrogen production amount ( Figure 9 and 10 ), and in subsequent in vivo and in vitro studies, the ultrasonic conditions or the dosage of MoS2@Bi2S3 can be changed to piezoelectrically catalyze H2 generation as needed.

[0209] 6. Research on catalytic characteristics and antioxidant ability

[0210] (1) Determination of the ability to scavenge ·OH by the TMB method

[0211] Prepare a solution containing 120 μL of FeSO4·7H2O (1 mM), 120 μL of H2O2 (10 mM), and 120 μL of MoS2@Bi2S3 (200, 100, 50 μg / mL) prepared in Example 1 at different concentrations in 840 μL of NaAC-HAC buffer (0.5 M, pH 4.5). After uniform mixing, keep it away from light. Ultrasonic it with an ultrasonic therapeutic instrument (0, 1.5 or 2.5 W / cm 2 , 1.0 MHz) for 10 minutes. After centrifuging for 5 minutes, take 100 μL of the supernatant and mix it with 100 μL of TMB chromogenic reagent (5 mM). Incubate for 5 minutes and measure the absorbance of the product ox-TMB at 650 nm. Use deionized water instead of the sample solution (MoS2@Bi2S3 solution) as blank control group 1, and use deionized water instead of the sample solution and H2O2 as blank control group 2, and measure the absorbance of blank control group 1 and blank control group 2. Determine the influence of Bi2S3 and MoS2 (200 μg / mL) on ·OH according to the same method above. Calculate the ·OH elimination rate according to the following formula.

[0212]

[0213] In the formula, A control 1 is the absorbance of blank control group 1, A control 2 is the absorbance of blank control group 2, and A sample is the absorbance of the sample experimental group.

[0214] (2) Detection of the ability to degrade H2O2 (CAT-like activity) by Ti(SO4)2 method

[0215] Mix 500 μL of the MoS2@Bi2S3 solutions prepared in Example 1 with concentrations of 500, 400, and 200 μg / mL uniformly with 500 μL of H2O2 solution (10 mM), and under dark conditions, sonicate with a sonicator at 2.5 W / cm 2 , after sonication for 10 minutes, centrifuge for 5 minutes, take 100 μL of the supernatant and add 50 μL of Ti(SO4)2 detection solution. After incubating at room temperature for 5 minutes, measure the absorbance of the product Ti-O2 at 420 nm. Disperse 500 μL of MoS2@Bi2S3 (200 μg / mL) in the same volume of buffer solutions with different pH values (pH 5.0, 6.5, 7.4, and 8.0), and study the effect of pH on the degradation of H2O2 by the same method. Use deionized water instead of the sample solution as blank control group 1, and use deionized water instead of the sample solution and H2O2 as blank control group 2, and measure the absorbance of blank control group 1 and blank control group 2. Calculate the degradation rate of H2O2 according to the following formula.

[0216]

[0217] In the formula, A control 1 is the absorbance of blank control group 1, A control 2 is the absorbance of blank control group 2, A sample is the absorbance of the sample experimental group.

[0218] The piezoelectric effect can not only generate an electric field, but also regulate redox reactions by controlling the distribution of electrons and holes. Further explored the effect of the piezoelectric effect on the antioxidant enzyme performance of MoS2 in MoS2@Bi2S3. First, evaluated the scavenging ability of Bi2S3, MoS2, and MoS2@Bi2S3 against hydrogen peroxide (H2O2) and hydroxyl radicals (·OH). Both Bi2S3 and MoS2 can scavenge ·OH and H2O2, and MoS2@Bi2S3 shows stronger ROS scavenging ability. When sonication is applied, the degradation effect of the three on ROS is significantly enhanced. In terms of ·OH scavenging, Bi2S3 performs better than MoS2 at a higher sonication power (2.5 W / cm 2 ), while the ·OH scavenging ability of MoS2@Bi2S3 is significantly stronger than that of the single component ( Figure 11 A). Under the conditions of a concentration of 200 μg / mL and sonication (2.5 W / cm 2 , 10 minutes), the scavenging rate of MoS2@Bi2S3 for ·OH can reach ~90%. Sonication generally improves the scavenging efficiency of ·OH, and the higher the sonication power, the more significant the scavenging effect ( Figure 11A). The H2 generated by ultrasound also has the effect of scavenging ·OH, but the effect of ultrasound on the content of ·OH is very small. Therefore, the scavenging of ·OH is the synergistic result of the action of H2 and MoS2@Bi2S3-like antioxidant enzymes. Similarly, under the action of ultrasound, MoS2@Bi2S3 can also enhance the degradation effect of H2O2 by mimicking the activity of catalase (CAT) ( Figure 11 C). Further studies show that the scavenging of both H2O2 and ·OH is concentration-dependent, and the pH value has little effect on the degradation of H2O2 ( Figure 11 B-D).

[0219] Application Example

[0220] The MoS2@Bi2S3 and MoS2@Bi2S3∈HA prepared in Example 1 were tested and analyzed in terms of hemolytic experiment, cytotoxicity, intracellular total ROS level, and cytokine content in the supernatant of RAW264.7 cells, as follows.

[0221] 1. Hemolytic experiment

[0222] The potential hemolysis of MoS2@Bi2S3 was evaluated by examining its ability to lyse Lewis rat red blood cells. The 20% red blood cell suspension was mixed with MoS2@Bi2S3∈HA prepared in Example 1 at a concentration of 200 μg / mL and an aqueous solution of MoS2@Bi2S3 at a concentration of 200 μg / mL, respectively. After incubation, the mixture was centrifuged, and the hemolysis rate was compared with the normal saline of the negative control and deionized water as the positive control group. As Figure 12 shown, the clarity of the samples in different experimental groups was comparable to that of the supernatant of the negative control group, and the appearance of red hemoglobin in the red blood cells was not observed, indicating that the samples did not cause hemolysis, had good biosafety, and could be further explored for their piezoelectric catalytic production of H2 and electrostimulation treatment effects in vivo and in vitro.

[0223] 2. Cytotoxicity investigation

[0224] The effect of MoS2@Bi2S3∈HA prepared in Example 1 on the cell viability of RAW264.7 and ADSCs cells was investigated by the CCK-8 method. When the sample concentration was 200 μg / mL, the viability of RAW264.7 cells was greater than 80% under the ultrasound action of 1.5 W / cm 2 , 5 minutes ( Figure 13 A); the viability of ADSCs cells was greater than 80% under the ultrasound action of 0.5 W / cm 2 , 8 minutes ( Figure 13B). The results showed that when the sample concentration did not exceed 200 μg / mL, under a certain ultrasonic effect, there was no obvious toxicity to cells, showing good biosafety. Therefore, MoS2@Bi2S3∈HA prepared in Example 5 with a concentration less than or equal to 200 μg / mL can be used for subsequent exploration of antioxidant activity.

[0225] 3. Quantitative investigation of the total intracellular ROS level

[0226] Flow cytometry was used to quantitatively analyze the ability of MoS2@Bi2S3∈HA to scavenge intracellular ROS. Compared with the Control group, a large amount of ROS was generated in RAW264.7 cells under LPS stimulation. Different concentrations of MoS2@Bi2S3∈HA prepared in Example 7 were co-incubated with inflamed RAW264.7 cells and then subjected to ultrasonic treatment. The results are as Figure 14 shown. The proportion of ROS-positive cells of MoS2@Bi2S3∈HA prepared in Example 7 at different concentrations all decreased, and with the increase in the concentration of MoS2@Bi2S3∈HA, the decrease in the proportion of ROS-positive cells was more significant.

[0227] 4. Effects of MoS2@Bi2S3∈HA on the expression of TNF-α, IL-6 and IL-1β in RAW264.7 cells

[0228] After being stimulated by LPS, inflamed RAW264.7 cells secrete a large amount of inflammatory factors such as TNF-α, IL-6 and IL-1β, thus exacerbating the deterioration of RA. An ELISA kit was used to detect the content of pro-inflammatory factors in the supernatant of RAW264.7 cells to evaluate the in vitro anti-inflammatory activity of MoS2@Bi2S3∈HA prepared in Example 1. As Figure 15 (A-C) shows, when the concentration of MoS2@Bi2S3∈HA prepared in Example 1 was 200 μg / mL, under ultrasonic (1.5 W / cm 2 , 5 minutes) treatment, it could significantly inhibit the expression of inflammatory factors such as TNF-α, IL-6 and IL-1β in RAW264.7 cells, indicating its good anti-inflammatory effect.

[0229] 5. Effects of MoS2@Bi2S3∈HA on the expression of TGF-β1 in RAW264.7 cells and ADSCs cells

[0230] By establishing a 2D culture system, RAW264.7 cells and ADSCs cells were cultured in a pro-inflammatory environment under LPS stimulation. After their functions were damaged, MoS2@Bi2S3∈HA prepared in Example 1 with a concentration of 200 μg / mL was added for incubation. After ultrasonic treatment, an ELISA kit was used to detect the concentration of TGF-β1 in the cell supernatant. From Figure 16As shown, under the action of ultrasound, MoS2@Bi2S3∈HA can significantly enhance the content of TGF-β1. It is speculated that ultrasound-catalyzed H2 production in combination with electrical stimulation can significantly induce the differentiation of ADSCs.

[0231] 6. Treatment of CIA rat arthritis with MoS2@Bi2S3∈HA

[0232] A CIA rat model was established. The CIA rats were grouped and intra-articular injections were performed every three days for treatment. They were respectively given normal saline, HA, MoS2@Bi2S3∈HA or MoS2@Bi2S3. By the 15th day, the arthritis scores and paw thicknesses of the model group given normal saline were still on the rise ( Figure 17 A), while in the group treated with MoS2@Bi2S3∈HA + US, the arthritis scores continued to decline with the prolongation of treatment time, indicating that the symptoms of RA were effectively controlled. After two injections combined with daily ultrasound intervention, the swelling of the paw was significantly relieved and the thickness was significantly reduced ( Figure 17 B), and both the arthritis score and paw thickness of the MoS2@Bi2S3∈HA + US group were the lowest values. Although ultrasound alone or HA treatment alleviated the symptoms of RA to a certain extent, the MoS2@Bi2S3 + US treatment group significantly enhanced the anti-RA effect. Blood routine, liver and kidney function parameters, and liver and kidney tissue morphology studies showed that there were no significant abnormalities in the MoS2@Bi2S3∈HA + US treatment group, fully demonstrating the high safety of MoS2@Bi2S3∈HA + US treatment. Histopathological results showed ( Figure 18 A) that the joint cavities of the ultrasound-alone or HA treatment groups were only slightly improved, and synovial hyperplasia and pannus still existed significantly; while the joint cavity morphology of the MoS2@Bi2S3∈HA + US treatment group was significantly improved, the continuity of cartilage tissue was enhanced and pathological symptoms were alleviated, indicating its strong anti-inflammatory ability. Through Safranin O staining ( Figure 18 B) and Masson staining ( Figure 18 C) analysis of ankle joint sections showed that although there were still slight joint cavity stenosis and inflammatory cell infiltration, however, in the MoS2@Bi2S3∈HA + US treatment group, cartilage layer regeneration could be clearly observed at the edge of the joint cavity, and at the same time, collagen expression was significantly enhanced ( Figure 18 C), indicating its function of promoting cartilage repair.

[0233] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the design concept and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A preparation method of MoS2@Bi2S3∈HA biological piezoelectric material, characterized in that, The steps are as follows: Add MoS2@Bi2S3 into a hyaluronic acid solution and mix. After stirring at room temperature, a MoS2@Bi2S3∈HA bio-piezoelectric material is obtained.

2. The preparation method of the MoS2@Bi2S3∈HA biological piezoelectric material according to claim 1, wherein, The concentration of the hyaluronic acid solution is 0.25 - 3 mg / mL; the mass ratio of hyaluronic acid to MoS2@Bi2S3 in the hyaluronic acid solution is 2 - 80:1; the preparation method of MoS2@Bi2S3 is: Add Bi2S3 nanorods, Na2MoO4·2H2O and NH2CSNH2 into deionized water and stir at room temperature, and obtain it through a hydrothermal reaction.

3. The MoS2@Bi2S3∈HA bio-piezoelectric material prepared by the preparation method according to claim 1 or 2.

4. The application of the MoS2@Bi2S3∈HA bio-piezoelectric material according to claim 3 as a mimetic antioxidant enzyme.

5. The application according to claim 4, characterized in that, The mimetic antioxidant enzyme is mimetic catalase or mimetic glutathione reductase.

6. The application of the MoS2@Bi2S3∈HA bio-piezoelectric material according to claim 3 in enhancing the activity of mimetic antioxidant enzymes under ultrasonic action.

7. The application of the MoS2@Bi2S3∈HA bio-piezoelectric material according to claim 3 as a reactive oxygen scavenger.

8. The application of the MoS2@Bi2S3∈HA bio-piezoelectric material according to claim 3 as a piezo-catalyst in the production of hydrogen under ultrasonic action.

9. The application of the MoS2@Bi2S3∈HA bio-piezoelectric material according to claim 3 in the preparation of drugs for treating inflammatory diseases.

10. The application of the MoS2@Bi2S3∈HA bio-piezoelectric material according to claim 3 in the preparation of drugs for cartilage repair.

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