Magnetic antibacterial bone cement and method of preparation

Abstract

The present application relates to a kind of magnetic antibacterial bone cement and preparation method, bone cement is composed of two parts of powder and liquid, the ratio of powder and liquid is (2-3):1g / mL, powder component and mass percentage are as follows: polymethyl methacrylate 45-89%, 440C martensitic steel silver powder 10-50%, benzoyl peroxide 1-5%;In 440C martensitic steel silver powder, the mass percentage of 440C martensitic stainless steel powder is 65-95%, and the mass percentage of silver powder is 5-35%;Liquid component and mass percentage are as follows: methyl methacrylate monomer 94.90-99.89%, N, N dimethyl-p-toluidine 0.1-5%, hydroquinone 0.01-0.1%.The bone cement of the present application has moderate magnetic heating rate, can realize long-term stable development, and has certain bacteriostasis.

Description

Technical Field

[0001] This invention belongs to the field of bone repair materials, specifically relating to a magnetic antibacterial bone cement and its preparation method. Background Technology

[0002] Artificial joint replacement technology has become increasingly mature, and the long-term survival rate of prostheses has significantly improved. However, various factors can lead to joint prosthesis failure. Currently, clinical findings show that aseptic loosening and deep infection can both cause joint replacement surgery failure. Bone tumors or bone metastases from malignant tumors are also among the causes of joint prosthesis fixation failure. For bone tumors, surgical resection is often chosen, supplemented by chemotherapy, radiotherapy, and other postoperative treatments. With the current serious problems of air and water pollution, the prominent aging population, and improved medical and health conditions leading to longer life expectancies for malignant tumor patients, the number of bone tumor cases is expected to increase. Given China's large population base, there will be even more patients with bone metastases. Bone tumors or bone joint infections often cause bone defects, making it crucial to implant excellent filling materials to repair bone defects and restore bone mechanical properties. Bone cement has excellent biocompatibility, plasticity, and curing ability, and is widely used in clinical practice. However, bone cement lacks anti-bone tumor function and antibacterial properties, making it highly susceptible to infection at the implantation site.

[0003] Many researchers have modified bone cement to impart antitumor or antibacterial properties by loading it with drugs or doping it with particles possessing magnetothermal or photothermal properties. The most commonly used magnetic materials are ferric oxide (Fe2O3) or ferric oxide (Fe3O4) magnetic powder. Yuanyi Zheng and Zhechuan Mei's team successfully used PMMA bone cement and calcium phosphate bone cement with added ferric oxide to thermally resect liver tumors in animals. However, ferric oxide alone suffers from poor heat transfer efficiency in antitumor applications, and its heating rate under alternating magnetic fields is too rapid, reaching a maximum temperature of 500℃, posing a risk of burning other tissues. Furthermore, ferric oxide lacks antibacterial properties. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention proposes a magnetic antibacterial bone cement with a moderate magnetothermal heating rate, capable of long-term stable imaging, and possessing certain antibacterial properties, as well as its preparation method.

[0005] One of the above-mentioned objectives of the present invention is achieved by the following technical solution:

[0006] A magnetic antibacterial bone cement consists of two parts: powder and liquid, with a powder-to-liquid ratio of (2-3):1 g / mL.

[0007] The powder composition and mass percentage are as follows: polymethyl methacrylate 45-89%, 440C martensitic stainless steel silver powder 10-50%, benzoyl peroxide 1-5%; in the 440C martensitic stainless steel silver powder, the mass percentage of 440C martensitic stainless steel powder is 65-95%, and the mass percentage of silver powder is 5-35%.

[0008] The liquid components and their mass percentages are as follows: methyl methacrylate monomer 94.90-99.89%, N,N-dimethyl-p-toluidine 0.1-5%, and hydroquinone 0.01-0.1%.

[0009] Furthermore, polymethyl methacrylate has a particle size distribution range of 0.2–150 μm and a molecular weight range of 100,000–1,000,000.

[0010] Moreover, the particle size distribution of 440C martensitic steel silver powder ranges from 0.1 to 100 μm.

[0011] Furthermore, the particle size distribution range of the 440C martensitic steel powder in the silver powder is 2.6–100 μm, and the particle size distribution range of the silver powder is 0.1–45 μm.

[0012] Furthermore, the preparation method of 440C martensitic steel silver powder is as follows:

[0013] (1) Place 440C martensitic steel powder into anhydrous ethanol. The ratio of steel powder to anhydrous ethanol is (1:5) to 10. Stir continuously for 10 to 60 minutes to obtain a steel powder-ethanol mixture.

[0014] (2) Place the silver powder into anhydrous ethanol, with the ratio of silver powder to anhydrous ethanol being (1:5) to 20, and stir continuously for 10 to 60 minutes to obtain a silver powder-ethanol mixture.

[0015] (3) Add the mixture from step (2) to the steel powder-ethanol mixture from step (1) and mix for 10-30 minutes.

[0016] (4) After mixing evenly, the excess anhydrous ethanol is removed by sieving and filtration to obtain moist 440C martensitic steel silver powder.

[0017] (5) Then transfer the composite powder to a vacuum oven, keep the vacuum degree less than 5 Pa, and dry it at 37-100℃ for 3-24 hours;

[0018] (6) The dried and cooled composite powder is ball-milled for 1-3 hours and screened to obtain the required 440C martensitic steel silver powder.

[0019] The second objective of this invention is achieved through the following technical solution:

[0020] A method for preparing the magnetic antibacterial bone cement as described above includes the following steps:

[0021] (1) Mix polymethyl methacrylate, benzoyl peroxide and 440C martensitic silver powder evenly in a mixing device for 3 to 24 hours;

[0022] (2) Take out the well-mixed bone cement powder, weigh the powder and liquid according to the ratio of bone cement powder to liquid (2-3):1g / mL, add the bone cement liquid to the bone cement powder, stir for 10-60s, and prepare bone cement.

[0023] The advantages and positive effects of this invention are as follows:

[0024] This invention selects 440C martensitic steel powder (micron-sized particles) and silver powder (containing nanoparticles) with varying particle size distributions. Through alcohol slurry preparation, flotation, filtration, adhesion, and vacuum drying, a 440C martensitic steel-silver powder with a well-proportioned particle size distribution is obtained. The obtained 440C martensitic steel-silver powder is then added to bone cement, simultaneously replacing the contrast agent and Fe3O4 magnetic material in the bone cement. This prevents the risk of excessively rapid heating and high temperatures that could burn other tissues under an alternating magnetic field, and imparts a certain degree of contrast agent to the bone cement, exhibiting the advantages of a moderate magnetothermal heating rate and long-term stable contrast. It also enhances the wear resistance and durability of the bone cement. When the 440C martensitic steel-silver powder is in the bone cement, the alternating magnetic field causes hysteresis heating of the bone cement to above 40°C, which can kill or eliminate tumor cells and achieve high-temperature sterilization. It also prolongs the setting time of the bone cement, preventing the rapid accumulation of energy during polymerization and reducing the thermal damage to tissues caused by the polymerization of bone cement. Meanwhile, the unique antibacterial properties of silver can enhance the antibacterial properties of bone cement. Simultaneously, the uniform distribution of 440C martensitic steel silver powder within the bone cement forms an electromagnetic shielding network structure. The reflected electromagnetic waves provide an electromagnetic shielding effect, reducing the maximum temperature of the bone cement's magnetic hysteresis heating and preventing thermal damage to tissues caused by the magnetocaloric effect. The resulting magnetic antibacterial bone cement is injectable and has suitable strength, making it suitable for fixing various fractures and filling bone defects. Attached Figure Description

[0025] Figure 1 These are imaging images of the magnetic antibacterial bone cement tested in Examples 1-3 of this invention and the existing control joint cement. The second column in the images is not used in this invention.

[0026] Figure 2 These are images showing the temperature rise results of magnetic antibacterial bone cement tested under a magnetic field in Examples 1-3 of this invention: 2a, control sample; 2b, sample of Example 1; 2c, sample of Example 2; 2d, sample of Example 3. Detailed Implementation

[0027] The structure of the present invention will be further described below with reference to the accompanying drawings and embodiments. It should be noted that these embodiments are descriptive and not limiting.

[0028] A magnetic antibacterial bone cement consists of two parts: powder and liquid, with a powder-to-liquid ratio of (2-3):1 g / mL.

[0029] The powder composition and mass percentage are as follows: 45-89% polymethyl methacrylate, 10-50% 440C martensitic stainless steel silver powder, and 1-5% benzoyl peroxide. Preferably, the mass percentage of 440C martensitic stainless steel silver powder is 10-42%; more preferably, it is 10-30%. Within the 440C martensitic stainless steel silver powder, the mass percentage of 440C martensitic stainless steel powder is 65-95%, and the mass percentage of silver powder is 5-35%. Further, within the 440C martensitic stainless steel silver powder, the mass percentage of 440C martensitic stainless steel powder is 74-92%, and the mass percentage of silver is 8-26%.

[0030] The liquid components and their mass percentages are as follows: methyl methacrylate monomer 94.90-99.89%, N,N-dimethyl-p-toluidine 0.1-5%, and hydroquinone 0.01-0.1%.

[0031] The aforementioned polymethyl methacrylate (PMMA) has a particle size distribution range of 0.2–150 μm and a molecular weight range of 100,000–1,000,000. Preferably, the PMMA powder has a particle size distribution range of 5–80 μm and a molecular weight range of 200,000–600,000. More specifically, the PMMA powder preferably has a particle size distribution range of 20–60 μm and a molecular weight range of 300,000–500,000.

[0032] The particle size distribution range of the above-mentioned 440C martensitic steel silver powder is 0.1 to 100 μm. Preferably, the particle size distribution range of the 440C martensitic steel silver powder is 0.3 to 74 μm; more preferably, the particle size distribution range of the 440C martensitic steel silver powder is 0.45 to 45 μm.

[0033] The particle size distribution range of the 440C martensitic steel powder in the above-mentioned silver powder is 2.6 to 100 μm, and the particle size distribution range of the silver powder is 0.1 to 45 μm.

[0034] The preparation method of the above-mentioned 440C martensitic steel silver powder is as follows:

[0035] (1) Place 440C martensitic steel powder into anhydrous ethanol. The ratio of steel powder to anhydrous ethanol is (1:5) to 10. Stir continuously for 10 to 60 minutes to obtain a steel powder-ethanol mixture.

[0036] (2) Place the silver powder into anhydrous ethanol, with the ratio of silver powder to anhydrous ethanol being (1:5) to 20, and stir continuously for 10 to 60 minutes to obtain a silver powder-ethanol mixture.

[0037] (3) Add the mixture from step (2) to the steel powder-ethanol mixture from step (1) and mix for 10-30 minutes.

[0038] (4) After mixing evenly, the excess anhydrous ethanol is removed by sieving and filtration to obtain moist 440C martensitic steel silver powder.

[0039] (5) Then transfer the composite powder to a vacuum oven, keep the vacuum degree less than 5 Pa, and dry it at 37-100℃ for 3-24 hours;

[0040] (6) The dried and cooled composite powder is ball-milled for 1-3 hours and screened to obtain the required 440C martensitic steel silver powder.

[0041] The preparation method of the magnetic antibacterial bone cement of the present invention includes the following steps:

[0042] (1) Mix polymethyl methacrylate, benzoyl peroxide and 440C martensitic silver powder evenly in a mixing device for 3 to 24 hours;

[0043] (2) Take out the well-mixed bone cement powder, weigh the powder and liquid according to the ratio of bone cement powder to liquid (2-3):1g / mL, add the bone cement liquid to the bone cement powder, stir for 10-60s, and prepare bone cement.

[0044] Example 1

[0045] A magnetic antibacterial bone cement comprises powder and liquid in a powder-to-liquid ratio of 2.5:1 (g / mL). The powder comprises 68% polymethyl methacrylate, 30% 440C martensitic stainless steel silver powder, and 2% benzoyl peroxide. The liquid comprises 98.9% methyl methacrylate monomer, 1% N,N-dimethyl-p-toluidine, and 0.1% hydroquinone. The polymethyl methacrylate has a particle size distribution of 0.2–150 μm and a molecular weight of 350,000. The 440C martensitic stainless steel silver powder has a particle size distribution of 0.3–74 μm. In the 440C martensitic stainless steel silver powder, the mass percentage of 440C martensitic stainless steel powder is 92%, and the mass percentage of silver is 8%.

[0046] The pretreatment method for 440C martensitic steel silver powder is as follows:

[0047] (1) 440C martensitic steel powder is placed in anhydrous ethanol at a ratio of 1:10 and stirred continuously for 60 minutes to obtain a steel powder-ethanol mixture.

[0048] (2) Add silver powder to anhydrous ethanol at a ratio of 1:20 and stir continuously for 60 minutes to obtain a silver powder-ethanol mixture.

[0049] (3) Add the mixture from step (2) to the steel powder-ethanol mixture from step (1) and mix for 30 minutes.

[0050] (4) After mixing evenly, the excess anhydrous ethanol is removed by sieving and filtration to obtain moist 440C martensitic steel silver powder.

[0051] (5) Then transfer the composite powder to a vacuum oven, keep the vacuum degree less than 5pa, and dry it at 100℃ for 3h.

[0052] (6) The dried and cooled composite powder was ball-milled for 3 hours and screened to obtain the required 440C martensitic steel silver powder;

[0053] The preparation method of magnetic antibacterial bone cement is as follows:

[0054] (1) Mix polymethyl methacrylate, benzoyl peroxide and 440C martensitic steel silver powder evenly in a mixing device for 3 hours;

[0055] (2) Take out the well-mixed bone cement powder, and weigh out the powder and liquid according to the ratio of bone cement powder to liquid of 2.5:1 (g / mL). Add the bone cement liquid to the bone cement powder and stir for 30 seconds to complete the preparation of bone cement.

[0056] The prepared bone cement is filled into the fracture or bone defect site that needs to be filled or stabilized, and it can be operated for 17 minutes and cured in 28 minutes.

[0057] The prepared bone cement was used to create circular specimens with a diameter of 3 mm and a thickness of 3 mm. These specimens were then photographed and observed under X-ray, and compared with conventional joint bone cement specimens. Figure 1 As shown, the sample of Example 1 is also clearly visible under X-ray, indicating that the magnetic antibacterial bone cement of the present invention has good radioactivity.

[0058] An alternating magnetic field test was conducted on the bone cement sample of Example 1. Under a 50 kHz alternating magnetic field, the bone cement reached a temperature of 64.3°C within 2 minutes, lower than the 81.2°C of the control sample (containing iron oxide bone cement). This indicates that the magnetic antibacterial bone cement of the present invention exhibits a lower temperature rise under a variable magnetic field than existing bone cements, thus avoiding the risk of excessive temperature burns to other tissues during use.

[0059] Example 2

[0060] A magnetic antibacterial bone cement comprises powder and liquid in a powder-to-liquid ratio of 2:1 (g / mL). The powder comprises 77% polymethyl methacrylate, 20% 440C martensitic stainless steel silver powder, and 3% benzoyl peroxide. The liquid comprises 96.9% methyl methacrylate monomer, 3% N,N-dimethyl-p-toluidine, and 0.1% hydroquinone. The polymethyl methacrylate has a particle size distribution of 5–80 μm and a molecular weight of 350,000. The 440C martensitic stainless steel silver powder has a particle size distribution of 0.45–45 μm. In the 440C martensitic stainless steel silver powder, the mass percentage of 440C martensitic stainless steel powder is 74%, and the mass percentage of silver is 26%.

[0061] The pretreatment method for 440C martensitic steel silver powder is as follows:

[0062] (1) Place 440C martensitic steel powder into anhydrous ethanol. The ratio of steel powder to anhydrous ethanol is 1:8. Stir continuously for 10 minutes to obtain a steel powder-ethanol mixture.

[0063] (2) Add silver powder to anhydrous ethanol at a ratio of 1:15 and stir continuously for 30 minutes to obtain a silver powder-ethanol mixture.

[0064] (3) Add the mixture from step (2) to the steel powder-ethanol mixture from step (1) and mix for 10 minutes.

[0065] (4) After mixing evenly, the excess anhydrous ethanol is removed by sieving and filtration to obtain moist 440C martensitic steel silver powder.

[0066] (5) Then transfer the composite powder to a vacuum oven, keep the vacuum degree less than 5pa, and dry it at 70℃ for 5h.

[0067] (6) The dried and cooled composite powder was ball-milled for 2 hours and screened to obtain the required 440C martensitic steel silver powder;

[0068] The preparation method of magnetic antibacterial bone cement is as follows:

[0069] (1) Mix polymethyl methacrylate, benzoyl peroxide and 440C martensitic steel silver powder evenly in a mixing device for 3 hours;

[0070] (2) Take out the well-mixed bone cement powder, weigh the powder and liquid according to the ratio of bone cement powder to liquid of 2:1 (g / mL), add the bone cement liquid to the bone cement powder, stir for 30s, and complete the preparation of bone cement.

[0071] The prepared bone cement is filled into the fracture or bone defect site that needs to be filled or stabilized. The operation time is 14 minutes, and the curing is completed in 23 minutes.

[0072] The bone cement prepared in Example 2 was used to make circular specimens with a diameter of 3 mm and a thickness of 3 mm. These specimens were then photographed and observed under X-ray, and compared with conventional joint bone cement specimens. Figure 1 As shown, the sample from Example 2 is also clearly visible under X-ray. This indicates that the magnetic antibacterial bone cement of the present invention has good radioactivity.

[0073] The bone cement sample from Example 2 was tested under an alternating magnetic field. The bone cement reached a temperature of 55.5°C within 2 minutes under a 50kHz alternating magnetic field, lower than the 81.2°C of the control sample (containing iron oxide bone cement). This indicates that the magnetic antibacterial bone cement of the present invention has a lower temperature rise under a variable magnetic field than existing bone cements, thus avoiding the risk of excessive temperature burning of other tissues during use.

[0074] Example 3

[0075] A magnetic antibacterial bone cement comprises powder and liquid in a powder-to-liquid ratio of 2:1 (g / mL). The powder comprises 85% polymethyl methacrylate, 10% 440C martensitic stainless steel silver powder, and 5% benzoyl peroxide. The liquid comprises 94.99% methyl methacrylate monomer, 5% N,N-dimethyl-p-toluidine, and 0.01% hydroquinone. The polymethyl methacrylate has a particle size distribution of 5–80 μm and a molecular weight of 350,000. The 440C martensitic stainless steel silver powder has a particle size distribution of 0.45–45 μm. In the 440C martensitic stainless steel silver powder, the mass percentage of 440C martensitic stainless steel powder is 65%, and the mass percentage of silver is 35%.

[0076] The pretreatment method for 440C martensitic steel silver powder is as follows:

[0077] (1) Place 440C martensitic steel powder into anhydrous ethanol. The ratio of steel powder to anhydrous ethanol is 1:5. Stir continuously for 20 minutes to obtain a steel powder-ethanol mixture.

[0078] (2) Add silver powder to anhydrous ethanol at a ratio of 1:16 and stir continuously for 20 minutes to obtain a silver powder-ethanol mixture.

[0079] (3) Add the mixture from step (2) to the steel powder-ethanol mixture from step (1) and mix for 20 minutes.

[0080] (4) After mixing evenly, the excess anhydrous ethanol is removed by sieving and filtration to obtain moist 440C martensitic steel silver powder.

[0081] (5) Then transfer the composite powder to a vacuum oven, keep the vacuum degree less than 5pa, and dry it at 80℃ for 4h.

[0082] (6) The dried and cooled composite powder was ball-milled for 1 hour and screened to obtain the required 440C martensitic steel silver powder;

[0083] The preparation method of magnetic antibacterial bone cement is as follows:

[0084] (1) Mix polymethyl methacrylate, benzoyl peroxide and 440C martensitic steel silver powder evenly in a mixing device for 3 hours;

[0085] (2) Take out the well-mixed bone cement powder, weigh the powder and liquid according to the ratio of bone cement powder to liquid of 2:1 (g / mL), add the bone cement liquid to the bone cement powder, stir for 30s, and complete the preparation of bone cement.

[0086] The prepared bone cement is filled into the fracture or bone defect site that needs to be filled or stabilized. The operation time is 8 minutes, and the curing is completed in 15 minutes.

[0087] The bone cement prepared in Example 3 was used to make circular specimens with a diameter of 3 mm and a thickness of 3 mm. These specimens were then photographed and observed under X-ray, and compared with conventional joint bone cement specimens. Figure 1 As shown, the sample from Example 3 is also clearly visible under X-ray. This indicates that the magnetic antibacterial bone cement of the present invention has good radioactivity.

[0088] The bone cement sample from Example 3 was tested under an alternating magnetic field. The bone cement reached a temperature of 41.8°C within 2 minutes under a 50kHz alternating magnetic field, lower than the 81.2°C of the control sample (containing iron oxide bone cement). This indicates that the magnetic antibacterial bone cement of the present invention exhibits a lower temperature rise under a variable magnetic field than existing bone cements, thus avoiding the risk of excessive temperature burns to other tissues during use.

[0089] Example 4

[0090] A magnetic antibacterial bone cement comprises powder and liquid in a powder-to-liquid ratio of 2:1 (g / mL). The powder comprises 53% polymethyl methacrylate, 42% 440C martensitic stainless steel silver powder, and 5% benzoyl peroxide. The liquid comprises 94.99% methyl methacrylate monomer, 5% N,N-dimethyl-p-toluidine, and 0.01% hydroquinone. The polymethyl methacrylate has a particle size distribution of 10–80 μm and a molecular weight of 350,000. The 440C martensitic stainless steel silver powder has a particle size distribution of 15–53 μm. In the 440C martensitic stainless steel silver powder, the mass percentage of 440C martensitic stainless steel powder is 95%, and the mass percentage of silver is 5%.

[0091] The pretreatment method for 440C martensitic steel silver powder is as follows:

[0092] (1) Place 440C martensitic steel powder into anhydrous ethanol. The ratio of steel powder to anhydrous ethanol is 1:5. Stir continuously for 20 minutes to obtain a steel powder-ethanol mixture.

[0093] (2) Add silver powder to anhydrous ethanol at a ratio of 1:13 and stir continuously for 20 minutes to obtain a silver powder-ethanol mixture.

[0094] (3) Add the mixture from step (2) to the steel powder-ethanol mixture from step (1) and mix for 20 minutes.

[0095] (4) After mixing evenly, the excess anhydrous ethanol is removed by sieving and filtration to obtain moist 440C martensitic steel silver powder.

[0096] (5) Then transfer the composite powder to a vacuum oven, keep the vacuum degree less than 5pa, and dry it at 80℃ for 4h.

[0097] (6) The dried and cooled composite powder was ball-milled for 1 hour and screened to obtain the required 440C martensitic steel silver powder;

[0098] The preparation method of magnetic antibacterial bone cement is as follows:

[0099] (1) Mix polymethyl methacrylate, benzoyl peroxide and 440C martensitic steel silver powder evenly in a mixing device for 3 hours;

[0100] (2) Take out the well-mixed bone cement powder, weigh the powder and liquid according to the ratio of bone cement powder to liquid of 2:1 (g / mL), add the bone cement liquid to the bone cement powder, stir for 30s, and complete the preparation of bone cement.

[0101] The prepared bone cement is filled into the fracture or bone defect site that needs to be filled or stabilized. The operation time is 18 minutes, and the curing is completed in 30 minutes.

[0102] Experimental Example 1

[0103] The physical properties of the bone cement prepared in Examples 1-4 were tested, and the test results are shown in Table 1:

[0104] Table 1

[0105] Test number Compressive strength (MPa) Flexural strength (MPa) Flexural modulus (MPa) Example 1 92.92±1.81 74.93±7.86 3369.28±231.05 Example 2 92.94±3.78 73.24±4.75 3564.29±232.60 Example 3 92.60±5.15 71.73±4.40 3427.19±179.07 Example 4 90.50±3.78 62.66±2.23 3046.41±175.64

[0106] As can be seen from Table 1, the mechanical properties of the magnetic antibacterial bone cement in Examples 1-4 of this invention after curing meet the requirements of the bone cement industry standard YY0459.

[0107] In this invention, 440C martensitic steel powder is prepared from conventional 440C stainless steel. 440C martensitic steel powder is commonly used in high-hardness cutting tools, abrasives, and 3D printing, exhibiting good hardness, wear resistance, and corrosion resistance. The silver powder possesses excellent antibacterial properties. The electromagnetic shielding network structure formed by the 440C martensitic steel silver powder in bone cement reflects some electromagnetic waves, achieving an electromagnetic shielding effect. This reduces the maximum magnetothermal temperature of the bone cement, preventing thermal damage to tissues caused by the magnetothermal effect. The bone cement of this invention is primarily used for filling or stabilizing fracture sites or bone defects.

[0108] The above-described specific embodiments are merely specific examples of the present invention. The patent protection scope of the present invention includes, but is not limited to, the product form and style of the above-described specific embodiments. Any appropriate changes or modifications made by a person skilled in the art that conform to the claims of the present invention should fall within the patent protection scope of the present invention.

Claims

1. A magnetic antibacterial bone cement, characterized in that: It consists of two parts: powder and liquid, with a powder to liquid ratio of (2-3):1g / mL; The powder composition and mass percentage are as follows: polymethyl methacrylate 45-89%, 440C martensitic stainless steel silver powder 10-50%, benzoyl peroxide 1-5%; in the 440C martensitic stainless steel silver powder, the mass percentage of 440C martensitic stainless steel powder is 65-95%, and the mass percentage of silver powder is 5-35%; the particle size distribution range of the 440C martensitic stainless steel silver powder is 0.1-100μm; the particle size distribution range of the 440C martensitic stainless steel powder is 2.6-100μm, and the particle size distribution range of the silver powder is 0.1-45μm. The liquid components and their mass percentages are as follows: methyl methacrylate monomer 94.90-99.89%, N,N-dimethyl-p-toluidine 0.1-5%, hydroquinone 0.01-0.1%.

2. The magnetic antibacterial bone cement according to claim 1, characterized in that: The particle size distribution of polymethyl methacrylate ranges from 0.2 to 150 μm, and the molecular weight ranges from 100,000 to 1,000,000.

3. The magnetic antibacterial bone cement according to claim 1, characterized in that: The preparation method of 440C martensitic steel silver powder is as follows: (1) Put 440C martensitic steel powder into anhydrous ethanol, the ratio of steel powder to anhydrous ethanol is 1: (5~10), and stir continuously for 10~60 min to obtain steel powder ethanol mixture slurry; (2) Put the silver powder into anhydrous ethanol, the ratio of silver powder to anhydrous ethanol is 1: (5~20), and stir continuously for 10~60 minutes to obtain a silver powder ethanol mixture. (3) Add the mixture from step (2) to the steel powder-ethanol mixture from step (1) and mix for 10-30 minutes. (4) After mixing evenly, the excess anhydrous ethanol is removed by sieving and filtration to obtain moist 440C martensitic steel silver powder. (5) Then transfer the composite powder to a vacuum oven, keep the vacuum degree less than 5 Pa, and dry it at 37~100℃ for 3~24h; (6) The dried and cooled composite powder is ball-milled for 1-3 hours and screened to obtain the required 440C martensitic steel silver powder.

4. A method for preparing magnetic antibacterial bone cement as described in any one of claims 1-3, comprising the following steps: (1) Mix polymethyl methacrylate, benzoyl peroxide and 440C martensitic steel silver powder evenly in a mixing device for 3~24h; (2) Take out the well mixed bone cement powder, weigh the powder and liquid according to the ratio of bone cement powder to liquid (2~3):1g / mL, add bone cement liquid to bone cement powder, stir for 10~60s, and prepare bone cement.

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