Ultrasonic response titanium oxide antibacterial medical implant material as well as preparation and application thereof

Abstract

The invention belongs to the technical field of antibacterial implant materials, and discloses an ultrasonic response titanium oxide antibacterial medical implant material as well as preparation and application thereof. The method comprises the following steps: 1) introducing titanium oxide seed crystals on the surface of a titanium-based substrate; and 2) putting the titanium-based matrix into which the titanium oxide seed crystals are introduced in the step 1) into a titanium precursor solution, regulating the reaction process through acid, and adding a surfactant for hydrothermal reaction to obtain a black titanium dioxide array material growing on the surface of the titanium-based matrix, namely the ultrasonic response titanium oxide antibacterial medical implant material. The method is simple, the prepared material can resist bacteria through ultrasonic response and has the characteristic of resisting bacterial infection for a long time, the nanorod array structure in the material is beneficial to osteoblast adhesion, proliferation and differentiation, and the osseointegration performance of the titanium-based material is improved. In addition, due to in-situ generation, the material disclosed by the invention is firmly combined with a titanium-based matrix and shows excellent coating stability. The material provided by the invention is used as a bone defect repair material.

Description

Technical Field

[0001] The invention belongs to the field of biomedical materials and inorganic functional materials, and specifically relates to an ultrasonic responsive titanium oxide antibacterial implant material and its preparation method and application Background Art

[0002] Bacteria are widely distributed in human life and the atmospheric environment, and the number of people who become ill due to bacterial infections is high every year. Since bone repair and transplantation operations are performed in an air environment, it is easy for staphylococci and bacilli in the air to be brought into the surgical site, leading to implant-related infections. Once an infection occurs, revision surgery is required, which brings great pain to the patient. Titanium and its alloys are widely used in bone defect repair, joint replacement, and tooth restoration due to their excellent mechanical strength, chemical stability, and biocompatibility. However, titanium-based implants face the risk of bacterial invasion and infection at the implant site, leading to surgical failure, during clinical use. This has become a major problem limiting the clinical application of titanium and its alloys.

[0003] In order to prevent implant-related infections, more and more researchers are paying attention to the antibacterial properties of implant materials. Modifying or coating the surface of implants can effectively avoid the extensive use of antibiotics and prevent the development of bacterial resistance to a certain extent. Currently, the common antibacterial modified coatings on the surface of implants include antibacterial adhesion coatings, contact bactericidal coatings, and release bactericidal coatings, but each has some limitations, such as the inability to achieve complete antibacterial adhesion, biosafety, and release stability, which hinders their clinical transformation and application.

[0004] Titanium dioxide is an implant antibacterial material with good biocompatibility, but due to its wide band gap and rapid electron-hole recombination, its antibacterial effect is poor and the therapeutic effect is not good. Therefore, the modification of titanium dioxide to enhance its antibacterial properties has become the focus of researchers now.

[0005] Therefore, there is an urgent need to develop a bone implant material that can resist postoperative bacterial infection to meet clinical use. Summary of the invention

[0006] In order to overcome the shortcomings and deficiencies of the above-mentioned prior art, the purpose of the present invention is to provide an ultrasonically responsive titanium oxide implant array material and a preparation method thereof, which greatly improves the antibacterial properties of the existing implant materials. The present invention forms a crystal nucleus on the surface of a titanium-based substrate by adding a titanium precursor solution and annealing, and then controls the molar ratio of titanium ions and hydrogen ions to react to generate a black titanium dioxide nanorod array, which has ultrasonic responsiveness, and the introduction of seed crystals promotes the directional growth of the nanoarray. At the same time, the in-situ growth of the seed crystals into a nanocolumn array makes the bonding strength between the array and the titanium-based substrate high, and the mechanical stability of the coating is good.

[0007] The purpose of the present invention is achieved through the following technical solutions: A method for preparing an ultrasonically responsive titanium oxide antibacterial medical implant material comprises the following steps: 1) Introducing titanium oxide seed crystals on the surface of the titanium-based substrate: placing the clean titanium-based substrate in a titanium precursor aqueous solution for reaction, and then performing annealing treatment to obtain titanium oxide seed crystals introduced on the surface of the titanium-based substrate; 2) Preparation of black titanium dioxide array material grown on the surface of a titanium-based substrate: The titanium-based substrate into which titanium oxide seed crystals were introduced in step 1) is placed in a titanium precursor solution, and the reaction process is regulated by an acid. A surfactant is then added for a hydrothermal reaction to obtain a black titanium dioxide array material grown on the surface of the titanium-based substrate, i.e., an ultrasonically responsive titanium oxide antibacterial medical implant material.

[0008] The clean titanium-based substrate in step 1) refers to the titanium-based substrate being treated to remove impurities and oxide layers; specifically, it refers to ultrasonic cleaning, acid cleaning, water cleaning, and drying to obtain a clean substrate.

[0009] The ultrasonic cleaning refers to cleaning with a mixed solution of water, acetone and 2-propanol; the volume ratio of water, acetone and 2-propanol is 1~2:1~2:1~2.

[0010] The ultrasonic time is 30 min to 90 min.

[0011] The acid used in the pickling process is a mixed solution of hydrofluoric acid, nitric acid and water; the mass concentration of the hydrofluoric acid is 40%, and the concentration of the nitric acid is analytical grade.

[0012] The volume ratio of the hydrofluoric acid, nitric acid and water is 1-4:1-4:200.

[0013] The titanium precursor in step 1) is tetrabutyl titanate, titanium tetrachloride or titanium isopropoxide.

[0014] The concentration of the titanium precursor aqueous solution in step 1) is 0.01 M~0.3 M.

[0015] The reaction temperature in step 1) is 55°C to 85°C, preferably 55°C to 75°C; the reaction time is 0.5 h to 10 h.

[0016] The annealing temperature in step 1) is 400°C to 800°C, preferably 450°C to 650°C; the annealing time is 1 h to 24 h.

[0017] The titanium precursor in step 2) is tetrabutyl titanate, titanium tetrachloride or titanium isopropoxide.

[0018] In step 2), the molar ratio of the titanium precursor to the hydrogen ions of the acid is (0.05-0.3):(2.5-7.5), preferably (0.1-0.3):(4-7.5).

[0019] The concentration of the titanium precursor in the solution of the titanium precursor solution and the acid is 0.05M-0.3M; the concentration of the acid in the solution of the titanium precursor solution and the acid is 2.5M-7.5M.

[0020] The acid in step 2) is hydrochloric acid.

[0021] In step 2), the titanium-based matrix introduced into the titanium oxide seed crystal in step 1) is placed in a titanium precursor solution, and the reaction process is regulated by acid, which means that the titanium-based matrix introduced into the titanium oxide seed crystal in step 1) is placed in a mixed solution of the titanium precursor solution and the acid; or the titanium-based matrix introduced into the titanium oxide seed crystal in step 1) is placed in a titanium precursor solution and an acid is added.

[0022] The surfactant in step 2) is one or more of hexadecyltrimethylammonium bromide, sodium dodecyl sulfate or ethylenediaminetetraacetic acid.

[0023] The ratio of the surfactant in step 2) to the titanium precursor in step 2) is (1-20) g: (0.05-3) mol, and can be further (1-10) g: (0.05-1) mol.

[0024] The temperature of the hydrothermal reaction in step 2) is 120°C to 220°C, preferably 150°C to 220°C; the time of the hydrothermal reaction is 2 h to 48 h.

[0025] After the hydrothermal reaction in step 2) is completed, the mixture is washed with water and dried.

[0026] The ultrasonic responsive titanium oxide antibacterial medical implant material is prepared by the method.

[0027] The ultrasonically responsive titanium oxide antibacterial medical implant material is used in bone defect repair materials such as limbs, spine and teeth.

[0028] The advantages of the present invention compared with the prior art are: (1) The black titanium dioxide implant array material prepared by the present invention can respond to the ultrasonic field to achieve antibacterial function, so that it has long-term anti-bacterial infection properties.

[0029] (2) The black titanium dioxide implant array material prepared by the present invention contains only Ti and O elements and is non-cytotoxic. The nanorod array structure is beneficial to the adhesion, proliferation and differentiation of osteoblasts and increases the bone integration performance of titanium-based materials.

[0030] (3) The black titanium dioxide implant array material prepared by the present invention is generated in situ and is firmly bonded to the titanium-based substrate, showing excellent coating stability.

[0031] (4) The preparation method of the present invention has simple process, low cost, short cycle and is suitable for industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 The scanning electron microscope (SEM) images of the materials of Example 1, Comparative Example 1 and Comparative Example 2 are shown; Figure 2 X-ray diffraction (XRD) diagrams of the materials of Example 1 and Comparative Example 1; Figure 3 X-ray photoelectron spectroscopy (XPS) diagrams of the materials of Example 1 and Comparative Example 1; Figure 4 This is the coating adhesion scratch diagram of the material in Example 1; Figure 5 The antibacterial effect diagram of the materials of Example 1 and Comparative Example 1; Figure 6 The cell SEM images of the materials of Example 1 and Comparative Example 1 are shown. DETAILED DESCRIPTION

[0033] The present invention is further described in detail below in conjunction with the examples, but the embodiments of the present invention are not limited thereto. If the specific conditions are not specified in the examples, they are carried out according to the conventional conditions or the conditions recommended by the manufacturer. If the manufacturer is not specified for the reagents or instruments used, they are all conventional products that can be purchased commercially. The reagents used in the examples can be purchased conventionally from the market unless otherwise specified.

[0034] Example 1 (1) Pretreatment of titanium substrate: Use a mixed solution of acetone, 2-propanol and water (volume ratio V 丙酮 :V 2-丙醇 :V 去离子水 =1:1:1) was used to ultrasonically clean a 2 cm diameter pure titanium sheet for 60 min to remove surface impurities, and then a mixed solution of hydrofluoric acid, nitric acid and deionized water (V 氢氟酸 :V 硝酸 :V 去离子水 =1:2:200) (the mass concentration of hydrofluoric acid is 40%, and the concentration of nitric acid is analytical grade) to remove the residual oxide layer by pickling, and then rinse with deionized water and dry naturally to obtain a pretreated pure titanium sheet; (2) Introducing titanium oxide seed crystals on the surface of the titanium-based substrate: immerse the sample treated in step (1) in 50 mL of a 0.2 M titanium tetrachloride aqueous solution at 60 °C for 6 h. After the reaction, take out the sample and anneal it at 600 °C for 2 h to obtain titanium oxide seed crystals introduced on the surface of pure titanium. (3) Preparation of black titanium dioxide array material grown on titanium-based substrate surface: The sample treated in step (2) was immersed in 60 mL of a mixed aqueous solution of titanium tetrachloride and hydrochloric acid with concentrations of 0.2 M and 6 M, respectively (the molar ratio of titanium tetrachloride to HCl in the mixed solution was 0.2:6), and 0.6 g of hexadecyltrimethylammonium bromide was added to the solution. The solution was transferred to a high-temperature reactor and reacted at 180 °C for 3 h. After the reaction was completed, it was washed with deionized water and naturally dried to obtain a black titanium dioxide array material grown on the surface of pure titanium.

[0035] Figure 1 3 is the SEM image of the materials of Example 1, Comparative Example 1 and Comparative Example 2. It can be seen from the image that the array width of the black titanium dioxide array implant material prepared in Example 1 is 50~200 nm, and the array coating thickness is about 6 μm, while the surfaces of the materials of Comparative Example 1 and Comparative Example 2 do not grow a uniform vertical nanocolumn array structure.

[0036] Figure 2 The XRD diagrams of the materials of Example 1 and Comparative Example 1 are compared with the standard card library, and it can be seen that the two are consistent in phase, both of which are rutile phase.

[0037] Figure 3 3 is the XPS graph of the materials of Example 1 and Comparative Example 1. It can be seen from the graph that Example 1 has more oxygen vacancy defects than Comparative Example 1, which can reduce the energy band gap of titanium dioxide and improve the ultrasonic responsiveness of the material.

[0038] Figure 4 This is a scratch diagram of the coating adhesion of the material in Example 1. It can be seen from the figure that after the material was scratched with a longitudinal force of 100N, the acoustic signal hardly fluctuated and the coating was not scratched, which indirectly verifies that the bonding force between the array coating and the pure titanium substrate is strong and the coating has high stability in use.

[0039] Figure 5 Statistical graph of the antibacterial rates of Example 1 and Comparative Example 1. It can be seen from the graph that the black titanium dioxide array implant material prepared in Example 1 exhibits good antibacterial properties, with the antibacterial rates against Escherichia coli and methicillin-resistant Staphylococcus aureus reaching 99.68% and 99.91%, respectively.

[0040] When ultrasound response antibacterial was performed, the ultrasound condition was 1.5 W·cm -2 power, ultrasonic for 10 min.

[0041] Figure 6The SEM images of mouse bone marrow mesenchymal stem cells on the surface of the materials of Example 1 and Comparative Example 1 are shown. From the images, it can be found that the spreading area of ​​the mouse bone marrow mesenchymal stem cells on the surface is large and the number of cell pseudopodia is large, indicating that this nanorod array material can promote the adhesion and proliferation of osteoblasts and facilitate the bone integration between the material and the bone after implantation.

[0042] Example 2 (1) Pretreatment of titanium substrate: Use a mixed solution of acetone, 2-propanol and deionized water (V 丙酮 :V 2-丙醇 :V 水 =1:1:1) was used to ultrasonically clean a 2 cm diameter pure titanium sheet for 60 min to remove surface impurities, and then a mixed solution of hydrofluoric acid, nitric acid and water (V 氢氟酸 :V 硝酸 :V 去离子水 =1:4:200) was pickled to remove the residual oxide layer, then rinsed with deionized water and dried naturally to obtain a pretreated pure titanium sheet; (2) Introducing titanium oxide seed crystals on the surface of the titanium-based substrate: immerse the sample treated in step (1) in 50 mL of a 0.2 M titanium tetrachloride aqueous solution at 65°C for 4 h. After the reaction, take out the sample and anneal it at 500°C for 2 h to obtain titanium oxide seed crystals deposited on the surface of pure titanium; (3) Preparation of black titanium dioxide array material grown on the surface of titanium-based substrate: The sample treated in step (2) was immersed in 60 mL of a mixed aqueous solution of 0.2 M and 6 M tetrabutyl titanate and hydrochloric acid, and 0.3 g of sodium dodecyl sulfate was added to the solution. The solution was transferred to a high-temperature reactor and reacted at 210°C for 6 h. After the reaction, it was washed with deionized water and naturally dried to obtain a black titanium dioxide array material grown on the surface of pure titanium.

[0043] The structure of the material prepared in this way is basically similar to that of Example 1, showing a nanorod morphology structure, and the oxygen vacancy defects inside are beneficial to improving its ultrasonic responsiveness.

[0044] Example 3 (1) Pretreatment of titanium substrate: Use a mixed solution of acetone, 2-propanol and deionized water (V 丙酮 :V 2-丙醇 :V 水 =1:1:1) was ultrasonically cleaned for 60 min to remove surface impurities, and then hydrofluoric acid and nitric acid (V 氢氟酸 :V 硝酸 :V 去离子水 =1:3:200) mixed aqueous solution is pickled to remove the residual oxide layer, then rinsed with deionized water and dried naturally to obtain a pretreated titanium alloy sheet; (2) Introducing titanium oxide seed crystals on the surface of the titanium-based substrate: immerse the sample treated in step (1) in 50 mL of a 0.15 M tetrabutyl titanate aqueous solution at 70 °C for 3 h. After the reaction, take out the sample and anneal it at 500 °C for 2 h to obtain titanium oxide seed crystals introduced on the surface of the titanium alloy. (3) Preparation of black titanium dioxide array material grown on the surface of titanium-based substrate: The sample treated in step (2) was immersed in 60 mL of a mixed aqueous solution of 0.3 M and 6 M titanium isopropoxide and hydrochloric acid, and 0.3 g of hexadecyltrimethylammonium bromide was added to the solution. The solution was transferred to a high-temperature reactor and reacted at 150°C for 20 h. After the reaction, it was washed with deionized water and naturally dried to obtain a black titanium dioxide array material grown on the surface of the titanium alloy.

[0045] The structure of the material prepared in this embodiment is basically similar to that of Embodiment 1, showing a nanorod morphology structure, and the oxygen vacancy defects inside are beneficial to improving its ultrasonic responsiveness.

[0046] Comparative Example 1 (1) Pretreatment of titanium substrate: Use a mixed solution of acetone, 2-propanol and deionized water (V 丙酮 :V 2-丙醇 :V 水 =1:1:1) was ultrasonically cleaned for 60 min to remove surface impurities, and then hydrofluoric acid and nitric acid (V 氢氟酸 :V 硝酸 :V 去离子水 =1:4:200) mixed aqueous solution is pickled to remove the residual oxide layer, then rinsed with deionized water and dried naturally to obtain a pretreated pure titanium sheet; (2) Preparation of titanium dioxide array material grown on the surface of titanium-based substrate: The sample treated in step (1) was immersed in 60 mL of a mixed aqueous solution of titanium tetrachloride and hydrochloric acid with concentrations of 0.2 M and 6 M, respectively, and 0.6 g of hexadecyltrimethylammonium bromide was added to the solution. The solution was transferred to a high-temperature reactor and reacted at 180°C for 0.5 h. After the reaction was completed, it was washed with deionized water and naturally dried.

[0047] Comparative Example 2 (1) Pretreatment of titanium substrate: Use a mixed solution of acetone, 2-propanol and deionized water (V 丙酮 :V 2-丙醇 :V 水 =1:1:1) was ultrasonically cleaned for 60 min to remove surface impurities, and then hydrofluoric acid and nitric acid (V 氢氟酸 :V 硝酸 :V 去离子水=1:4:200) mixed aqueous solution is pickled to remove the residual oxide layer, then rinsed with deionized water and dried naturally to obtain a pretreated pure titanium sheet; (2) Preparation of titanium dioxide array material grown on the surface of titanium-based substrate: The sample treated in step 1 was immersed in 60 mL of a mixed aqueous solution of titanium tetrachloride and hydrochloric acid with concentrations of 0.1 M and 0.6 M, respectively. 0.2 g of ethylenediaminetetraacetic acid was added to the solution. The solution was transferred to a high-temperature reactor and reacted at 210 °C for 4 h. After the reaction, it was washed with deionized water and dried naturally.

[0048] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be regarded as equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. A method for preparing an ultrasonically responsive titanium oxide antibacterial medical implant material, characterized in that: The following steps are involved: 1) Introducing titanium oxide seed crystals on the surface of the titanium-based substrate: placing the clean titanium-based substrate in a titanium precursor aqueous solution for reaction, and then performing annealing treatment to obtain titanium oxide seed crystals introduced on the surface of the titanium-based substrate; 2) Preparation of black titanium dioxide array material grown on the surface of titanium-based substrate: placing the titanium-based substrate into which titanium oxide seed crystals are introduced in step 1) in a titanium precursor solution, and regulating the reaction process by acid, and then adding a surfactant for hydrothermal reaction to obtain a black titanium dioxide array material grown on the surface of the titanium-based substrate, i.e., an ultrasonically responsive titanium oxide antibacterial medical implant material; The titanium precursor in step 1) is tetrabutyl titanate, titanium tetrachloride or titanium isopropoxide; The titanium precursor in step 2) is tetrabutyl titanate, titanium tetrachloride or titanium isopropoxide; The molar ratio of the titanium precursor to the hydrogen ions of the acid in step 2) is (0.05-0.3): (2.5-7.5).

2. The method for preparing the ultrasonic responsive titanium oxide antibacterial medical implant material according to claim 1, characterized in that: The molar ratio of the titanium precursor to the hydrogen ions of the acid in step 2) is (0.1-0.3): (4-7.5).

3. The method for preparing the ultrasonic responsive titanium oxide antibacterial medical implant material according to claim 1, characterized in that: The reaction temperature in step 1) is 55°C to 85°C; the reaction time is 0.5 h to 10 h; The annealing temperature in step 1) is 400°C to 800°C; the annealing time is 1 h to 24 h; The temperature of the hydrothermal reaction in step 2) is 120°C to 220°C; the time of the hydrothermal reaction is 2 h to 48 h; The acid in step 2) is hydrochloric acid.

4. The method for preparing the ultrasonic responsive titanium oxide antibacterial medical implant material according to claim 3, characterized in that: The reaction temperature in step 1) is 55-75°C; The annealing temperature in step 1) is 450-650°C; The temperature of the hydrothermal reaction in step 2) is 150-220°C.

5. The method for preparing the ultrasonic responsive titanium oxide antibacterial medical implant material according to claim 1, characterized in that: The concentration of the titanium precursor aqueous solution in step 1) is 0.01 M to 0.3 M; In step 2), the concentration of the titanium precursor in the solution of the titanium precursor solution and the acid is 0.05 M to 0.3 M; the concentration of the acid in the solution of the titanium precursor solution and the acid is 2.5 M to 7.5 M.

6. The method for preparing the ultrasonic responsive titanium oxide antibacterial medical implant material according to claim 1, characterized in that: The surfactant in step 2) is one or more of hexadecyltrimethylammonium bromide, sodium dodecyl sulfate or ethylenediaminetetraacetic acid; The ratio of the surfactant in step 2) to the titanium precursor in step 2) is (1-20) g: (0.05-3) mol.

7. The method for preparing the ultrasonic responsive titanium oxide antibacterial medical implant material according to claim 1, characterized in that: In step 2), placing the titanium-based matrix introduced with the titanium oxide seed crystal in step 1) in a titanium precursor solution, and regulating the reaction process by acid means placing the titanium-based matrix introduced with the titanium oxide seed crystal in step 1) in a mixed solution of the titanium precursor solution and the acid; or placing the titanium-based matrix introduced with the titanium oxide seed crystal in step 1) in a titanium precursor solution and adding acid; After the hydrothermal reaction in step 2) is completed, wash with water and dry; The clean titanium-based substrate in step 1) refers to the titanium-based substrate being treated to remove impurities and oxide layers; specifically, it refers to ultrasonic cleaning, acid cleaning, water cleaning, and drying to obtain a clean substrate.

8. The method for preparing the ultrasonic responsive titanium oxide antibacterial medical implant material according to claim 7, characterized in that: In step 1), the ultrasonic cleaning refers to cleaning with a mixed solution of water, acetone and 2-propanol; the volume ratio of water, acetone and 2-propanol is 1~2:1~2:1~2; The ultrasound time is 30 min to 90 min; The acid used in the pickling process is a mixed solution of hydrofluoric acid, nitric acid and water; the mass concentration of the hydrofluoric acid is 40%, and the concentration of the nitric acid is analytical grade; The volume ratio of the hydrofluoric acid, nitric acid and water is 1-4:1-4:

200.

9. An ultrasonically responsive titanium oxide antibacterial medical implant material obtained by the preparation method according to any one of claims 1 to 8.

10. The use of the ultrasonic responsive titanium oxide antibacterial medical implant material according to claim 9, characterized in that: The ultrasonically responsive titanium oxide antibacterial medical implant material is used as a bone defect repair material.

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