A multifunctional antibacterial coated bone implant device based on a selective vacuum infusion process and a method of making the same

Abstract

The application discloses a multifunctional antibacterial coating bone implant device based on a selective vacuum perfusion process and a preparation method thereof. The method comprises the following steps: 1) pretreating a titanium alloy base; 2) performing anodic oxidation treatment on the pretreated titanium alloy base to construct a nanotube structure on the surface of the titanium alloy base; 3) selectively coating the treated titanium alloy base with a hydrogel adhesive, then immersing the titanium alloy base in a povidone iodine mixed solution to perform vacuum perfusion, and performing post-treatment, then again performing selective coating, immersing the titanium alloy base in a solution containing a bone growth promoting factor to perform vacuum perfusion, and performing post-treatment, then again performing selective coating, immersing the titanium alloy base in a solution containing a blood vessel growth promoting factor to perform vacuum perfusion, and performing post-treatment; and 4) encapsulating the obtained sample surface with an in-situ self-polymerized polydopamine layer, washing and freeze-drying. The bone implant device has antibacterial, bone growth promoting and blood vessel growth promoting functions, and can greatly improve the curative effect on bone fracture symptoms accompanied by infection.

Description

Technical Field

[0001] This invention relates to the field of biomedical material preparation, specifically to a multifunctional antibacterial coated bone implant device based on selective vacuum perfusion technology and its preparation method. Background Technology

[0002] With the improvement of people's living standards, the transportation industry has developed rapidly, and the incidence of fractures and bone defects caused by traffic accidents has also been increasing. Patients with fractures and bone defects are often highly susceptible to infection, which can lead to nonunion of fractures, bringing enormous physical and psychological burdens to patients.

[0003] Currently, the main clinical treatments for fractures are external or internal fixation techniques, often combined with antibiotics to treat infections during the fracture and bone defect process. However, this approach is prone to drug resistance. Antimicrobial coatings, as an emerging technology with immense clinical application potential, have attracted the interest of researchers. However, antimicrobial coating technology is still in its early stages of development. Many coatings suffer from short-term antimicrobial effects and limited processing methods, failing to meet the requirements for long-term infection control and promoting fracture healing, thus significantly diminishing the technology's practicality and commercialization value.

[0004] Iodine, as a highly effective and broad-spectrum bactericide, has been used to treat bacterial infections for over 160 years, and there are almost no reports in the literature of microorganisms developing resistance to iodine. However, due to some of iodine's own physicochemical properties (such as its low solubility in water and its tendency to sublimate at room temperature and pressure), its application as a bactericide is limited.

[0005] Meanwhile, growth factors, as a class of polypeptides that regulate cell growth and other cellular functions through binding to specific, high-affinity cell membrane receptors, play a crucial regulatory role in cellular growth and metabolism. Osteogenic factors can promote osteoogenesis and inhibit osteoclastization, thereby regulating bone metabolism balance; while angiogenic factors can promote angiogenesis, and studies have shown that angiogenesis has a synergistic effect on osteoogenesis.

[0006] Therefore, the research focus of this invention is to overcome the difficulties in the application of iodine and, at the same time, combine it with osteogenic and angiogenic growth factors to bring better performance to bone implant devices. Summary of the Invention

[0007] The purpose of this invention is to address the problems of low drug loading efficiency, short antibacterial duration, insignificant tissue regeneration activity, and uncontrollable surface distribution of antibacterial / tissue regeneration active components in existing bone implant devices, and to provide a multifunctional antibacterial coated bone implant device based on selective vacuum perfusion technology and its preparation method.

[0008] The solution adopted in this invention is as follows:

[0009] A method for preparing a multifunctional antibacterial coated bone implant device based on selective vacuum perfusion technology includes the following steps:

[0010] 1) Pretreatment: First, the titanium alloy substrate is polished multiple times to remove the oxide film on its surface and obtain a smooth surface. Then, the titanium alloy is cleaned in sequence with acetone, ethanol and deionized water under ultrasonic conditions to remove oil and impurities from its surface.

[0011] 2) Anodizing: The titanium alloy substrate after the above pretreatment is subjected to anodizing treatment to construct a nanotube structure on its surface;

[0012] 3) Coating and Impregnation: Based on the designed pattern, the titanium alloy substrate treated in step 2) is selectively coated with a hydrogel adhesive, then impregnated in a povidone-iodine mixture for vacuum perfusion. After post-treatment, selective coating is performed again, followed by impregnation in a solution containing osteogenic growth factor for vacuum perfusion. After post-treatment, selective coating is performed again, followed by impregnation in a solution containing angiogenic growth factor for vacuum perfusion. Post-treatment is then performed again. The area of ​​selective coating can be adjusted according to design requirements, and each type of vacuum perfusion can be performed multiple times.

[0013] 4) Encapsulation: The sample obtained in step 3) is encapsulated in situ with a self-polymerized polydopamine layer. After rinsing and freeze-drying, a multifunctional antibacterial coated bone implant device is obtained.

[0014] In the above technical solution, further, the anodic oxidation conditions in step 2) are as follows: the formulation of the anodic oxidation electrolyte is 48.6-84.3wt% glycerol, 15.4-49.9wt% deionized water, 0.1-0.5wt% ammonium fluoride, 0.1-0.5wt% sodium sulfate, and 0.1-0.5wt% ammonium sulfate; the voltage is 25-50V, the distance between the sample and the electrode is 15-25cm, and the reaction time is 1-8 hours.

[0015] Further, the hydrogel adhesive mentioned in step 3) is a hydrogel adhesive with wet adhesion and high cohesive strength, preferably one or more of dopamine-modified light-curing adhesives and polyacrylic acid / polyethyleneimine powder adhesives.

[0016] Furthermore, when using a hydrogel adhesive, specifically a polyacrylic acid / polyethyleneimine powder adhesive, the sample area to be coated must be pre-treated with deionized water beforehand, followed by application of the powder adhesive for swelling and adhesion. After adhesion, a heavy object coated with glycerol is used for pressing, and the sample is then dried in a 37°C forced-air oven to ensure complete adhesion. When using a dopamine-modified photocurable adhesive, photocuring is required after coating.

[0017] Furthermore, the povidone-iodine mixed solution contains 5-20 wt% povidone-iodine powder, 0.25-0.75 wt% sodium alginate, 0.5-5 wt% glycerol, and the remainder is commercial povidone-iodine solution, wherein the viscosity of sodium alginate is ≥0.002 Pas.

[0018] The osteogenic factor solution contains 0.01-0.025 wt% osteogenic growth factor, 0.25-0.75 wt% sodium alginate, 0.5-5 wt% glycerol, and the remainder is water; the osteogenic factor is one or more of BMP-2, TGF-β, RGD peptide, and IGF.

[0019] The aforementioned angiogenesis-promoting factor solution contains 0.01-0.025 wt% angiogenesis-promoting factor, 0.25-0.75 wt% sodium alginate, 0.5-5% glycerol, and the remainder is water; the angiogenesis-promoting factor is one or more of VEGF, bFGF, AFGF, placental growth factor, IL-8, HGF, TNF-α, and endothelial growth factor.

[0020] Furthermore, the vacuum infusion parameters are as follows: vacuum degree is 1-100Pa, vacuuming time is 5-30min, and pressure holding time after vacuuming is 2-20min; the post-treatment after vacuum infusion is as follows: rinsing with deionized water, drying at a temperature below 35℃, the vacuum infusion process can be repeated 5-10 times, and finally removing the surface adhesive.

[0021] Furthermore, in the encapsulation process, the polymerization conditions for the polydopamine layer are as follows: the sample is fixed so that its surface is immersed in a dopamine solution, and the sample is turned over every 30 minutes to ensure the uniformity of the coating; the concentration of the dopamine solution is 6-15 mg / ml, pH=8.5, and the polymerization time is 4-6 hours.

[0022] Compared with the prior art, the present invention has the following advantages:

[0023] 1) This invention combines anodizing, selective coating, multiple-cycle vacuum perfusion, and in-situ self-polymerization processes, using titanium alloy, povidone-iodine, sodium alginate, glycerol, bone growth factor, angiogenesis factor, and dopamine as raw materials to prepare a multifunctional coating material with antibacterial, bone-promoting, and angiogenesis-promoting functions on the surface of bone implants. First, a nanotube structure is controllably constructed on the surface of the titanium alloy as a "container." Then, antibacterial, bone-promoting, and angiogenesis-promoting components are selectively loaded onto the surface. Finally, encapsulation is performed to form a "sealed tube" structure, enabling efficient loading and long-term release of each active component, thus improving the therapeutic effect on infected fractures.

[0024] 2) This invention innovatively utilizes a hydrogel adhesive with wet adhesion and high cohesive strength for selective coating, enabling the selective coating of antibacterial, osteogenic, and angiogenic components onto different areas of the titanium alloy surface. This process can meet the needs of infected fractures, bone defects, and other lesions requiring anti-infection function in certain specific areas, while surrounding areas require osteogenic and angiogenic functions. This design allows for personalized device customization according to the patient's actual condition, greatly improving efficacy and achieving both effective prevention and treatment of bone infections and significantly increasing the treatment efficiency of bone defects. Furthermore, the hydrogel adhesive's wet adhesion properties are maintained during vacuum perfusion without adhesion failure, and the hydrogel can prevent other active components from entering the coated titanium nanotubes for a short period. Moreover, after each stage of selective coating and vacuum perfusion, the high cohesive strength of the hydrogel adhesive itself allows for residue-free peeling from the substrate surface, cleverly realizing the innovative use of hydrogel adhesives.

[0025] 3) In this invention, active components (iodine and growth factors) are loaded inside titanium nanotubes and sealed with polydopamine, overcoming the problem of low stability of active components (iodine is prone to sublimation, growth factors are prone to decomposition, etc.). The mixed solution formula used in the vacuum infusion process is an innovative design of this invention for vacuum conditions. Among them, povidone-iodine is the effective antibacterial component, sodium alginate is the thickening component to effectively prevent the solution from boiling up under high vacuum conditions, and sodium alginate has excellent biocompatibility. The addition of glycerol can well ensure that the solution does not freeze under high vacuum conditions and prevent the solution from boiling up, ensuring that the antibacterial solution can enter the nanotubes stably and smoothly for efficient loading.

[0026] 4) This invention uses a multi-cycle vacuum perfusion process, combined with vacuuming, to overcome the technical challenge of high surface tension at the nanotube opening preventing the solution from entering the nanotube. This enables efficient loading of antibacterial, osteogenic, and angiogenic components into titanium nanotubes. Compared to other simpler processes such as impregnation, ultrasound, and electrophoresis, the loading of active components is increased several times. Furthermore, by combining the "thickening effect" of sodium alginate and the encapsulation process of polydopamine at the opening of the titanium nanotube, a long-term release (sustaining release) effect of active components can be achieved, matching the physiological characteristics of long-term infection treatment and long osteogenic cycles.

[0027] 5) The active components used in this invention include antibacterial components, osteogenic components, and angiogenic components. The antibacterial components treat infection, and the angiogenic components promote angiogenesis. The treatment of infection and angiogenesis have a synergistic effect on osteoogenesis. In addition, the osteogenic components can significantly improve the treatment effect of fractures. Attached Figure Description

[0028] Figure 1This is a schematic diagram of the titanium nanotube structure on the surface of a titanium alloy bone implant device selectively coated three times by a hydrogel adhesive in an embodiment of the present invention (where the shaded area is the coating region).

[0029] Figure 2 SEM images of the titanium nanotube structure on the surface of bone implant devices before (a) and after (b) drug loading.

[0030] Figure 3 This is a SEM image of the surface of a bone implant device after vacuum drug loading, encapsulated using a PDA. Detailed implementation method:

[0031] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0032] In a specific embodiment of the present invention, a schematic diagram of the titanium nanotube structure on the surface of a titanium alloy bone implant device selectively coated three times by a hydrogel adhesive is shown below. Figure 1 As shown, (where (a) is the first selective coating, (b) is the second selective coating, and (c) is the third selective coating, with the shaded area representing the coating region). In other specific embodiments of the invention, the specific coating pattern (i.e., the region) for each selective coating can be adjusted and designed according to the specific circumstances of the patient's infected fracture site to achieve the purpose of treating infection and promoting bone formation, and the coating is customizable.

[0033] Example 1:

[0034] 1) First, use 500#, 800#, and 1000# sandpaper in sequence to polish the surface of the titanium alloy to remove the oxide film and obtain a smooth surface. Then, use acetone, ethanol, and deionized water in sequence under 100 watt ultrasonic conditions to clean the titanium alloy for 15 minutes to remove oil and other impurities from its surface.

[0035] 2) The pretreated titanium alloy substrate was subjected to anodizing treatment (the formulation of the anodizing electrolyte was 54.5wt% glycerol, 45wt% deionized water, 0.3wt% ammonium fluoride, 0.1wt% sodium sulfate, and 0.1wt% ammonium sulfate; the voltage was 30V, the distance between the sample and the electrode was 25cm, and the reaction time was 3 hours), and a titanium nanotube structure with a diameter of about 100nm was controllably constructed on its surface.

[0036] 3) According to the designed pattern, selectively coat the titanium alloy substrate with dopamine-modified methacrylic anhydride gelatin hydrogel adhesive (under light-proof conditions, use a masking mold, pour 10wt% dopamine-modified methacrylic anhydride gelatin solution into the mold cutout, use 405nm wavelength ultraviolet light to irradiate for 10min for in-situ curing, and remove the mold). Immerse the coated titanium alloy in a mixed solution of povidone-iodine / sodium alginate / glycerol (5wt% povidone-iodine powder, 0.25wt% sodium alginate with a viscosity greater than 0.002Pas, 1wt% glycerol, and the remainder is commercial povidone-iodine solution) for vacuum infusion (vacuum degree is 5Pa, vacuuming for 15min, and maintaining vacuum for 5min). After completion, rinse with deionized water 3 times, dry at a temperature below 35℃, and repeat the vacuum infusion process 5 times after drying. Finally, remove the surface adhesive.

[0037] 4) Then, selectively coat the titanium alloy a second time using the same hydrogel adhesive according to the pattern. The coated titanium alloy is then immersed in a 0.01wt% BMP-2 / 0.25wt% sodium alginate / 1wt% glycerol solution with a viscosity greater than 0.002Pas for vacuum infusion. Other parameters of the vacuum infusion process are the same as above.

[0038] 5) Then, selectively coat the titanium alloy three times using the same hydrogel adhesive according to the pattern. The coated titanium alloy is then immersed in a 0.01wt% VEGF / 0.25wt% sodium alginate / 1wt% glycerol solution with a viscosity greater than 0.002Pas for vacuum infusion. Other parameters of the vacuum infusion process are the same as above.

[0039] 6) The sample from step 5) was fixed in place and immersed in a 6 mg / ml dopamine / Tris-HCl (pH=8.5) solution for 4 hours using a needle clamp. The sample was fixed in the dopamine solution every 30 minutes and flipped over every 30 minutes. Finally, a polydopamine layer was encapsulated on the surface of the sample. After rinsing and freeze-drying, a bone implant device sample with a multifunctional antibacterial coating material was obtained.

[0040] 7) After 7 days of CCK-8 testing, the cell survival rate of the obtained bone implant device samples was 92.8% compared with the control group; the antibacterial rate of the samples was greater than 87% after 24 hours; and the release of povidone-iodine / osteogenic factor and angiogenic factor inside the titanium nanotubes was completed in about 28 days.

[0041] Example 2:

[0042] 1) First, use 500#, 800#, and 1000# sandpaper in sequence to polish the surface of the titanium alloy to remove the oxide film and obtain a smooth surface. Then, use acetone, ethanol, and deionized water in sequence under 100 watt ultrasonic conditions to clean the titanium alloy for 15 minutes to remove oil and other impurities from its surface.

[0043] 2) The pretreated titanium alloy substrate was subjected to anodizing treatment (the formulation of the anodizing electrolyte was 54.5wt% glycerol, 45wt% deionized water, 0.3wt% ammonium fluoride, 0.1wt% sodium sulfate, and 0.1wt% ammonium sulfate; the voltage was 30V, the distance between the sample and the electrode was 25cm, and the reaction time was 3 hours), and a titanium nanotube structure with a diameter of about 100nm was controllably constructed on its surface.

[0044] 3) According to the designed pattern, selectively coat the titanium alloy substrate with dopamine-modified methacrylic anhydride gelatin hydrogel adhesive (under light-proof conditions, use a masking mold, pour 10wt% dopamine-modified methacrylic anhydride gelatin solution into the mold cutout, use 405nm wavelength ultraviolet light to irradiate for 10min for in-situ curing, and remove the mold). Immerse the coated titanium alloy in a mixed solution of povidone-iodine / sodium alginate / glycerol (5wt% povidone-iodine powder, 0.25wt% sodium alginate with a viscosity greater than 0.002Pas, 1wt% glycerol, and the remainder is commercial povidone-iodine solution) for vacuum infusion (vacuum degree is 5Pa, vacuuming for 15min, and maintaining vacuum for 5min). After completion, rinse with deionized water 3 times, dry at a temperature below 35℃, and repeat the vacuum infusion process 5 times after drying. Finally, remove the surface adhesive.

[0045] 4) Then, selectively coat the titanium alloy a second time using the same hydrogel adhesive according to the pattern. The coated titanium alloy is then immersed in a 0.01wt% BMP-2 / 0.25wt% sodium alginate / 1wt% glycerol solution with a viscosity greater than 0.002Pas for vacuum infusion. Other parameters of the vacuum infusion process are the same as above.

[0046] 5) Then, selectively coat the titanium alloy three times using the same hydrogel adhesive according to the pattern. The coated titanium alloy is then immersed in a 0.01wt% VEGF / 0.25wt% sodium alginate / 1wt% glycerol solution with a viscosity greater than 0.002Pas for vacuum infusion. Other parameters of the vacuum infusion process are the same as above.

[0047] 6) The sample from step 5) was fixed in place and immersed in a 15 mg / ml dopamine / Tris-HCl (pH=8.5) solution for 6 hours for in-situ self-polymerization. The sample was fixed in the dopamine solution with a needle clamp every 30 minutes and flipped over every 30 minutes. Finally, a polydopamine layer was encapsulated on the surface of the sample. After rinsing and freeze-drying, a bone implant device sample with a multifunctional antibacterial coating material was obtained.

[0048] 7) Compared with Example 1, the concentration of dopamine and the polymerization time were increased. After 7 days of CCK-8 experiment, the cell survival rate of the obtained bone implant device sample was 90.1% compared with the control group; the antibacterial rate of the sample was greater than 80% after 24 hours; and the povidone-iodine / osteoinducing factor and angiogenic factor inside the titanium nanotube were released in about 39 days.

[0049] Example 3:

[0050] 1) First, use 500#, 800#, and 1000# sandpaper in sequence to polish the surface of the titanium alloy to remove the oxide film and obtain a smooth surface. Then, use acetone, ethanol, and deionized water in sequence under 100 watt ultrasonic conditions to clean the titanium alloy for 15 minutes to remove oil and other impurities from its surface.

[0051] 2) The pretreated titanium alloy substrate was subjected to anodizing treatment (the formulation of the anodizing electrolyte was 54.5wt% glycerol, 45wt% deionized water, 0.3wt% ammonium fluoride, 0.1wt% sodium sulfate, and 0.1wt% ammonium sulfate; the voltage was 30V, the distance between the sample and the electrode was 25cm, and the reaction time was 3 hours), and a titanium nanotube structure with a diameter of about 100nm was controllably constructed on its surface.

[0052] 3) According to the designed pattern, selectively coat the titanium alloy substrate with dopamine-modified methacrylic anhydride gelatin hydrogel adhesive (under light-proof conditions, use a masking mold, pour 10wt% dopamine-modified methacrylic anhydride gelatin solution into the mold cutout, use 405nm wavelength ultraviolet light to irradiate for 10min for in-situ curing, and remove the mold). Immerse the coated titanium alloy in a mixed solution of povidone-iodine / sodium alginate / glycerol (15wt% povidone-iodine powder, 0.25wt% sodium alginate with a viscosity greater than 0.002Pas, 1wt% glycerol, and the remainder is commercial povidone-iodine solution) for vacuum infusion (vacuum degree is 5Pa, vacuuming for 15min, and maintaining vacuum for 5min). After completion, rinse with deionized water 3 times, dry at a temperature below 35℃, and repeat the vacuum infusion process 5 times after drying. Finally, remove the surface adhesive.

[0053] 4) Then, selectively coat the titanium alloy a second time using the same hydrogel adhesive according to the pattern. The coated titanium alloy is then immersed in a 0.01wt% BMP-2 / 0.25wt% sodium alginate / 1wt% glycerol solution with a viscosity greater than 0.002Pas for vacuum infusion. Other parameters of the vacuum infusion process are the same as above.

[0054] 5) Then, selectively coat the titanium alloy three times using the same hydrogel adhesive according to the pattern. The coated titanium alloy is then immersed in a 0.01wt% VEGF / 0.25wt% sodium alginate / 1wt% glycerol solution with a viscosity greater than 0.002Pas for vacuum infusion. Other parameters of the vacuum infusion process are the same as above.

[0055] 6) The sample from step 5) was fixed in place and immersed in a 6 mg / ml dopamine / Tris-HCl (pH=8.5) solution for 4 hours using a needle clamp. The sample was fixed in the dopamine solution every 30 minutes and flipped over every 30 minutes. Finally, a polydopamine layer was encapsulated on the surface of the sample. After rinsing and freeze-drying, a bone implant device sample with a multifunctional antibacterial coating material was obtained.

[0056] 7) Compared with Example 1, the amount of povidone-iodine powder added was increased. After 7 days of CCK-8 experiment, the cell survival rate of the obtained bone implant device sample was 89.6% compared with the control group; the antibacterial rate of the sample was greater than 95% after 24 hours; and the povidone-iodine / osteogenic factor and angiogenic factor inside the titanium nanotube were released completely in about 32 days.

[0057] Example 4:

[0058] 1) First, use 500#, 800#, and 1000# sandpaper in sequence to polish the surface of the titanium alloy to remove the oxide film and obtain a smooth surface. Then, use acetone, ethanol, and deionized water in sequence under 100 watt ultrasonic conditions to clean the titanium alloy for 15 minutes to remove oil and other impurities from its surface.

[0059] 2) The pretreated titanium alloy substrate was subjected to anodizing treatment (the formulation of the anodizing electrolyte was 54.3wt% glycerol, 45wt% deionized water, 0.5wt% ammonium fluoride, 0.1wt% sodium sulfate, and 0.1wt% ammonium sulfate; the voltage was 50V, the distance between the sample and the electrode was 15cm, and the reaction time was 3 hours), and a titanium nanotube structure with a diameter of about 150nm was controllably constructed on its surface.

[0060] 3) According to the designed pattern, selectively coat the titanium alloy substrate with dopamine-modified methacrylic anhydride gelatin hydrogel adhesive (under light-proof conditions, use a masking mold, pour 10wt% dopamine-modified methacrylic anhydride gelatin solution into the mold cutout, use 405nm wavelength ultraviolet light to irradiate for 10min for in-situ curing, and remove the mold). Immerse the coated titanium alloy in a mixed solution of povidone-iodine / sodium alginate / glycerol (5wt% povidone-iodine powder, 0.25wt% sodium alginate with a viscosity greater than 0.002Pas, 1wt% glycerol, and the remainder is commercial povidone-iodine solution) for vacuum infusion (vacuum degree is 5Pa, vacuuming for 15min, and maintaining vacuum for 5min). After completion, rinse with deionized water 3 times, dry at a temperature below 35℃, and repeat the vacuum infusion process 5 times after drying. Finally, remove the surface adhesive.

[0061] 4) Then, selectively coat the titanium alloy a second time using the same hydrogel adhesive according to the pattern. The coated titanium alloy is then immersed in a 0.01wt% BMP-2 / 0.25wt% sodium alginate / 1wt% glycerol solution with a viscosity greater than 0.002Pas for vacuum infusion. Other parameters of the vacuum infusion process are the same as above.

[0062] 5) Then, selectively coat the titanium alloy three times using the same hydrogel adhesive according to the pattern. The coated titanium alloy is then immersed in a 0.01wt% VEGF / 0.25wt% sodium alginate / 1wt% glycerol solution with a viscosity greater than 0.002Pas for vacuum infusion. Other parameters of the vacuum infusion process are the same as above.

[0063] 6) The sample from step 5) was fixed in place and immersed in a 6 mg / ml dopamine / Tris-HCl (pH=8.5) solution for 4 hours using a needle clamp. The sample was fixed in the dopamine solution every 30 minutes and flipped over every 30 minutes. Finally, a polydopamine layer was encapsulated on the surface of the sample. After rinsing and freeze-drying, a bone implant device sample with a multifunctional antibacterial coating material was obtained.

[0064] 7) Compared with Example 1, the process parameters of anodizing were changed to obtain titanium nanotubes with a diameter of approximately 150 nm. After 7 days of CCK-8 testing, the cell survival rate of the obtained bone implant device samples was 91.3% compared with the control group; the antibacterial rate of the samples was greater than 86.1% after 24 hours; and the povidone-iodine / osteoinducing factor and angiogenic factor inside the titanium nanotubes were completely released after about 22 days.

[0065] The embodiments described above are merely some preferred embodiments of the present invention, and are not intended to limit the invention. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the invention. Therefore, all technical solutions obtained by equivalent substitution or equivalent transformation fall within the protection scope of the present invention.

Claims

1. A method for preparing a multifunctional antibacterial coated bone implant device based on selective vacuum perfusion technology, characterized in that: Includes the following steps: 1) Pretreatment: First, the titanium alloy substrate is polished multiple times to remove the oxide film on its surface and obtain a smooth surface. Then, the titanium alloy is cleaned in sequence with acetone, ethanol and deionized water under ultrasonic conditions to remove oil and impurities from its surface. 2) Anodizing: The pretreated titanium alloy substrate was anodized to construct nanotube structures on its surface. The anodizing conditions were as follows: the anodizing electrolyte consisted of 48.6-84.3 wt% glycerol, 15.4-49.9 wt% deionized water, 0.1-0.5 wt% ammonium fluoride, 0.1-0.5 wt% sodium sulfate, and 0.1-0.5 wt% ammonium sulfate; the voltage was 25-50 V; the distance between the sample and the electrode was 15-25 cm; and the reaction time was 1-8 hours. 3) Coating and Impregnation: Based on the designed pattern, the titanium alloy substrate treated in step 2) is selectively coated with a hydrogel adhesive, then impregnated in a povidone-iodine mixed solution for vacuum perfusion. After the process, post-treatment is performed, followed by selective coating again, then impregnation in a solution containing osteogenic growth factor for vacuum perfusion. After the process, post-treatment is performed, followed by selective coating again, then impregnation in a solution containing angiogenic growth factor for vacuum perfusion. After the process, post-treatment is performed. The povidone-iodine mixed solution contains 5-20 wt% povidone-iodine powder, 0.25-0.75 wt% sodium alginate, 0.5-5 wt% glycerol, and the remainder is commercial povidone-iodine solution, wherein the viscosity of sodium alginate is ≥0.002 Pas. 4) Encapsulation: The sample obtained in step 3) is encapsulated in situ with a self-polymerized polydopamine layer. After rinsing and freeze-drying, a multifunctional antibacterial coated bone implant device is obtained.

2. The method for preparing the multifunctional antibacterial coated bone implant device based on selective vacuum perfusion technology according to claim 1, characterized in that: The hydrogel adhesive mentioned in step 3) is a hydrogel adhesive with wet adhesion and high cohesive strength, and is one or more of dopamine-modified light-curing adhesives and polyacrylic acid / polyethyleneimine powder adhesives.

3. The method for preparing the multifunctional antibacterial coated bone implant device based on selective vacuum perfusion technology according to claim 2, characterized in that: When using a hydrogel adhesive, such as a polyacrylic acid / polyethyleneimine powder adhesive, the sample area to be coated should be pre-treated with deionized water before being covered with the powder adhesive for swelling and adhesion. After the adhesive is adhered, a heavy object coated with glycerol should be used for pressure and drying to ensure complete adhesion. When using a dopamine-modified photocurable adhesive, photocuring is required after coating.

4. The method for preparing the multifunctional antibacterial coated bone implant device based on selective vacuum perfusion technology according to claim 1, characterized in that: The osteogenic growth factor solution contains 0.01-0.025 wt% osteogenic growth factor, 0.25-0.75 wt% sodium alginate, 0.5-5 wt% glycerol, and the remainder is water; the osteogenic growth factor is one or more of BMP-2, TGF-β, RGD peptide, and IGF.

5. The method for preparing the multifunctional antibacterial coated bone implant device based on selective vacuum perfusion technology according to claim 1, characterized in that: The aforementioned angiogenesis-promoting factor solution contains 0.01-0.025 wt% angiogenesis-promoting factor, 0.25-0.75 wt% sodium alginate, 0.5-5% glycerol, and the remainder is water; the angiogenesis-promoting factor is one or more of VEGF, bFGF, AFGF, placental growth factor, IL-8, HGF, TNF-α, and endothelial growth factor.

6. The method for preparing the multifunctional antibacterial coated bone implant device based on selective vacuum perfusion technology according to claim 1, characterized in that: The vacuum infusion parameters are as follows: vacuum degree is 1-100 Pa, vacuuming time is 5-30 min, and pressure holding time after vacuuming is 2-20 min; the post-treatment after vacuum infusion is as follows: rinsing with deionized water, drying at a temperature below 35°C, the vacuum infusion process is repeated 5-10 times, and finally the surface adhesive is removed.

7. The method for preparing the multifunctional antibacterial coated bone implant device based on selective vacuum perfusion technology according to claim 1, characterized in that: In the encapsulation process, the polymerization conditions for the polydopamine layer are as follows: the sample is fixed so that its surface is immersed in a dopamine solution, and the sample is turned over every 30 minutes to ensure the uniformity of the coating. The dopamine solution concentration is 6-15 mg / ml, pH=8.5, and the polymerization time is 4-6 hours.

8. A multifunctional antibacterial coated bone implant device, characterized in that, It is prepared by the method described in any one of claims 1-7.

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