A barium titanate-hydroxyapatite coating based on a titanium substrate and a method of manufacture
A three-dimensional barium titanate-hydroxyapatite coating was prepared on a titanium substrate using a hydrothermal method, which solved the problem of insufficient bonding strength between titanium alloys and bone tissue. This resulted in a multifunctional bio-coating with good biocompatibility and piezoelectric effect, making it suitable for bone repair implants.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- BAOJI UNIV OF ARTS & SCI
- Filing Date
- 2024-02-29
- Publication Date
- 2026-06-12
Smart Images
Figure CN118086902B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of surface coating preparation for biomedical materials, specifically to a method for preparing a barium titanate-hydroxyapatite composite coating on a titanium substrate surface. Background Technology
[0002] Titanium and its alloys are the preferred materials for orthopedic replacement and repair due to their excellent comprehensive mechanical properties, corrosion resistance, and biocompatibility, used to treat bone defects. However, clinical studies have revealed inherent drawbacks in titanium alloys. As bioinert materials, titanium alloys form a simple mechanical bond with the surrounding primary bone tissue after implantation, failing to establish a strong osseointegration. This can lead to implant loosening or even failure, causing secondary damage. Furthermore, postoperative infection of titanium implants remains one of the most common and serious complications.
[0003] Hydroxyapatite (HA) is highly similar to the inorganic components and structure of human bone tissue in terms of molecular structure and phosphorus-to-calcium ratio, exhibiting excellent bone integration and properties such as good osteoconductivity, osseointegration, structural similarity, and biocompatibility. Therefore, it shows promising potential as a bone implant substitute for repairing bone defects. However, hydroxyapatite's fracture toughness is significantly lower than that of human bone tissue, resulting in poor mechanical properties in practical applications. Meanwhile, barium titanate (BaTiO3) ceramics possess unique piezoelectric effects and excellent biocompatibility and bioactivity. When applied to bone repair implants, they can effectively promote osteoblast proliferation, differentiation, and new bone formation. Therefore, researchers have conducted extensive studies on BaTiO3 / HA composite materials, with results indicating that this composite can effectively promote the bone repair process. However, the mechanical properties of BaTiO3 / HA composites are far from meeting clinical requirements. In addition, most composite coating materials are limited by their manufacturing processes and cannot meet the requirements of multifunctional bone implants. The resulting coatings often have problems such as insufficient adhesion to bone tissue, low bonding strength, and poor application effects, which further hinder the widespread application of titanium implants. Summary of the Invention
[0004] To address the aforementioned deficiencies in the existing technology, the present invention aims to provide a method for preparing three-dimensional barium titanate-hydroxyapatite nanorods using a hydrothermal method, as well as a coating. This coating adheres tightly to bone tissue and exhibits high bonding strength, meeting the requirements for multifunctional bone implants.
[0005] The present invention is achieved through the following technical solution.
[0006] According to one aspect of the present invention, a method for preparing a barium titanate-hydroxyapatite coating based on a titanium substrate is provided, comprising:
[0007] Titanium substrate pretreatment: The titanium substrate is ground and polished, ultrasonically cleaned, and air-dried.
[0008] Coating preparation:
[0009] The titanium substrate was placed in a sodium hydroxide hydrothermal solution, heated to 200~220℃, and kept at that temperature for 2 hours to complete the hydrothermal deposition of sodium titanate.
[0010] The titanium substrate after hydrothermal deposition of sodium titanate was rinsed, dried, and kept warm to obtain a sodium titanate coating on the surface of the titanium substrate.
[0011] A titanium substrate coated with sodium titanate was placed in a hydrothermal solution of barium hydroxide octahydrate, heated to 140-160°C, and held for 3 hours to complete the hydrothermal deposition of barium titanate.
[0012] The titanium substrate after barium titanate hydrothermal deposition is rinsed, dried, kept warm, and then acid-soaked. This process is repeated to obtain a sodium titanate-barium titanate coating on the surface of the titanium substrate.
[0013] The titanium substrate coated with sodium titanate-barium titanate was placed in norepinephrine-Tris-HCl buffer solution, stirred, removed, rinsed, dried, and kept warm.
[0014] The titanium substrate treated with buffer solution was placed in a hydrothermal solution of sodium glycerophosphate-disodium ethylenediaminetetraacetate and heated to 140-160℃ for 8-12 hours to complete the hydrothermal deposition of hydroxyapatite.
[0015] The titanium substrate after hydrothermal deposition of hydroxyapatite was rinsed, dried, and kept warm to obtain a barium titanate-hydroxyapatite coating on the surface of the titanium substrate.
[0016] Preferably, the substrate material is pretreated by grinding and polishing the titanium substrate material with 1000# and 4000# sandpaper until it is free of threads, and then ultrasonically cleaning it in acetone, deionized water and alcohol solutions for 10-20 minutes respectively.
[0017] Preferably, the molar concentration of the sodium hydroxide hydrothermal solution is 0.5~1 mol / L.
[0018] Preferably, the molar concentration of the hydrothermal solution of barium hydroxide octahydrate is 0.1~0.3 mol / L.
[0019] Preferably, the acid soaking is performed by soaking in an acetic acid solution with a molar concentration of 0.01 mol / L for 5 to 10 minutes.
[0020] Preferably, the buffer solution is prepared by mixing 0.01~0.02g of norepinephrine with 0.5~1mol / L Tris-HCl solution and stirring for 12~16h.
[0021] Preferably, the hydrothermal solution of sodium glycerophosphate-disodium ethylenediaminetetraacetate is prepared by dissolving sodium glycerophosphate (0.01~0.03 mol / L) and calcium disodium ethylenediaminetetraacetate (0.1~0.3 mol / L) in water, adjusting the pH to 8~11 with 0.5~1 mol / L sodium hydroxide, and mixing them together.
[0022] Preferably, the titanium substrate after sodium titanate hydrothermal deposition is rinsed with water, dried at 40~60℃, and kept warm for 20~30 minutes.
[0023] Preferably, the titanium substrate after barium titanate hydrothermal deposition is rinsed with water, dried at 40-60°C, kept warm for 15-30 minutes, then soaked in glacial acetic acid for 5-10 minutes, rinsed with water again, dried at 60-80°C, and kept warm for 20-30 minutes.
[0024] Preferably, the titanium substrate after hydrothermal deposition of hydroxyapatite is rinsed with water, dried at 40-60°C, and kept warm for 20-30 minutes.
[0025] In another aspect, the present invention provides a barium titanate-hydroxyapatite coating based on a titanium substrate prepared by the method described above. The barium titanate-hydroxyapatite coating is a dense nanocolumnar structure that can adhere to the surface of bone tissue and has piezoelectric properties and biocompatibility.
[0026] The present invention, by adopting the above technical solution, has the following beneficial effects:
[0027] 1. This invention constructs a three-dimensional Na2TiO3 nanorod structure on the surface of titanium through in-situ reaction, and prepares a barium titanate composite coating with hydroxyapatite attached to it to obtain a barium titanate-hydroxyapatite composite coating with multiple functions such as similarity to human bone tissue and good bonding strength and piezoelectric effect.
[0028] 2. This invention relates to the preparation of a barium titanate-hydroxyapatite active coating on the surface of medical titanium implants based on a titanium substrate. This material exhibits stable physical and chemical properties. The barium titanate in the prepared composite coating possesses a unique piezoelectric effect, generating piezoelectric stimulation upon polarization, thereby promoting osteoblast adhesion, proliferation, and differentiation. Simultaneously, hydroxyapatite, being similar to the main components of human bone tissue, possesses excellent biocompatibility and bioactivity. Furthermore, the hydroxyapatite, in a particulate form, coats the surface of barium titanate, effectively avoiding a series of problems such as implant loosening caused by its inherently poor fracture toughness. A multifunctional composite coating with good mechanical properties, bioactivity, and biocompatibility is thus obtained.
[0029] 3. This invention prepares barium titanate-hydroxyapatite nanoarray pillars on a titanium substrate using a simple hydrothermal reaction. By controlling the main process parameters: temperature (200~220℃) and time (2h), the morphology and size of sodium titanate crystals can be effectively controlled; temperature (140~160℃) and time (3h) can be effectively controlled, the morphology and size of barium titanate crystals can be effectively controlled; and temperature (140~160℃) and time (6~12h) can be effectively controlled, the adhesion of hydroxyapatite crystals can be effectively controlled. The formed nanorod-shaped crystals do not exhibit any breakage, further ensuring the bonding strength between the coating and the substrate material.
[0030] 4. The barium titanate-hydroxyapatite coating prepared by the hydrothermal method in this invention effectively solves the problem of relatively poor mechanical properties of single implant materials. Sodium titanate is grown in situ, eliminating interface issues with the substrate. Furthermore, the hydrothermal synthesis of BaTiO3 and hydroxyapatite, based on sodium titanate nanorods, also avoids interface problems. Therefore, the resulting composite coating possesses strong bonding strength, effectively ensuring the practical application of the implant, especially suitable for implantation sites subjected to certain loads.
[0031] 5. The composite coating prepared by the hydrothermal method of this invention has a three-dimensional nanorod structure, which not only has good mechanical properties and biocompatibility, but also has good adhesion to human bone tissue, further ensuring the effective integration of the implant into the human body and new bone growth.
[0032] 6. In the composite coating prepared by the hydrothermal method of this invention, the introduction of barium titanate piezoelectric material not only promotes osteoblast adhesion, proliferation and differentiation based on piezoelectric stimulation, but its good piezoelectric effect can also play a certain antibacterial role, thereby effectively improving the bacterial infection problem of the implant.
[0033] This invention uses a hydrothermal method for preparation. This method is simple, easy to operate, highly reproducible, uses readily available and inexpensive raw materials, and has good application prospects. It is expected to replace metal materials as medical implant materials and is suitable for large-scale industrial production. Attached Figure Description
[0034] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, do not constitute an undue limitation of the invention. In the drawings:
[0035] Figure 1 This is a surface morphology diagram of a barium titanate-hydroxyapatite coating prepared on a titanium substrate.
[0036] Figure 2 This is a cross-sectional morphology diagram of a barium titanate-hydroxyapatite coating prepared on the surface of a titanium substrate.
[0037] Figure 3a The image shows the entire 4mm scratch produced by a 0-40N scratch tester on a barium titanate-hydroxyapatite coating prepared on a titanium substrate.
[0038] Figure 3b The image shows a scratch tester image of the barium titanate-hydroxyapatite coating prepared on a titanium substrate material surface, showing the appearance of cracks in the coating at a depth of 3.1 mm. Detailed Implementation
[0039] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. The illustrative embodiments and descriptions of the present invention are used to explain the present invention, but are not intended to limit the present invention.
[0040] This invention provides a method for preparing a barium titanate-hydroxyapatite coating based on a titanium substrate, comprising the following steps:
[0041] 1) Pretreatment of titanium substrate material:
[0042] The titanium substrate material was polished with 1000# and 4000# sandpaper until there were no spiral marks. Then it was placed in acetone, alcohol, deionized water and alcohol solution respectively for ultrasonic cleaning for 10-20 minutes to remove surface dirt and air dry.
[0043] 2) Preparation of sodium hydroxide hydrothermal solution: At room temperature, dissolve 0.5~1 mol / L sodium hydroxide (NaOH) in water and stir until the solution becomes transparent for later use;
[0044] 3) Preparation of Na2TiO3 coating: Add the prepared sodium hydroxide hydrothermal solution to the reactor, place the substrate material in the sodium hydroxide hydrothermal solution, heat to 200~220℃, keep warm for 2h, and complete the hydrothermal deposition of sodium titanate;
[0045] 4) Post-treatment: After the sodium titanate hydrothermal deposition is completed, the titanium substrate is rinsed with water and kept in an oven at 40~60℃ for 20~30 min to obtain a sodium titanate Na2TiO3 coating.
[0046] 5) Preparation of barium hydroxide octahydrate hydrothermal solution: At room temperature, dissolve barium hydroxide octahydrate Ba(OH)2·8H2O with a concentration of 0.1~0.3mol / L in water and stir until the solution is transparent for later use;
[0047] 6) Preparation of BaTiO3 coating: Add the prepared hydrothermal solution of barium hydroxide octahydrate to the reaction vessel, and place the titanium substrate with sodium titanate coating in the hydrothermal solution, heat to 140~160℃, keep warm for 3h, and complete the hydrothermal deposition of barium titanate.
[0048] 7) Post-treatment: After the barium titanate hydrothermal deposition is completed, the titanium substrate is rinsed with water, and then kept in an oven at 40~60℃ for 15~30 min. Then it is soaked in 0.01mol / L glacial acetic acid for 5~10 min, then taken out and rinsed with water. It is then kept in an oven at 60~80℃ for 20~30 min to obtain the barium titanate BaTiO3 coating on the surface of the titanium substrate.
[0049] 8) Prepare norepinephrine-Tris-HCl buffer solution: At room temperature, dissolve 0.5~1mol / L Tris-HCl in water and add 0.01~0.02g of norepinephrine. Mix and stir for 12~16h until the solution becomes transparent for later use.
[0050] 9) Post-treatment: Place the titanium substrate with barium titanate coating in norepinephrine-Tris-HCl buffer solution, stir for 12 h, take out the sample, rinse it with water, and keep it in an oven at 40~60℃ for 20~30 min.
[0051] 10) Preparation of sodium glycerophosphate-calcium disodium ethylenediaminetetraacetate hydrothermal solution: At room temperature, add sodium glycerophosphate (C3H7Na2O6P) with a concentration of 0.01~0.03 mol / L and calcium disodium ethylenediaminetetraacetate (C3H7Na2O6P) with a concentration of 0.1~0.3 mol / L. 10 H 12 The mixture of CaN2 and Na2O8 is dissolved in water, and the pH is adjusted to 8-11 with 0.5-1 mol / L sodium hydroxide (NaOH).
[0052] 11) Preparation of barium titanate-hydroxyapatite coating: The prepared sodium glycerophosphate-disodium calcium ethylenediaminetetraacetate hydrothermal solution was added to the reaction vessel, and the titanium substrate treated with buffer solution was placed in the hydrothermal solution, heated to 140~160℃, and kept at the temperature for 6~12h to complete the hydrothermal deposition.
[0053] 12) Post-treatment: After hydrothermal deposition, remove the substrate and rinse it with water. Then, place it in an oven at 40-60℃ for 20-30 minutes to obtain a barium titanate-hydroxyapatite coating on the titanium substrate surface.
[0054] The barium titanate-hydroxyapatite active coating is a dense nanocolumnar structure coating that can adhere well to the surface of bone tissue.
[0055] The present invention will be further described below through specific embodiments.
[0056] Example 1
[0057] 1) Polish the titanium substrate material with 1000# and 4000# sandpaper until there are no spiral marks. Then place it in acetone, alcohol, deionized water and alcohol solution respectively for ultrasonic cleaning for 10 minutes to remove surface dirt. Let it air dry to obtain titanium substrate.
[0058] 2) Dissolve 1 mol / L sodium hydroxide (NaOH) in water to prepare a hydrothermal solution, and stir until the solution becomes transparent for later use;
[0059] 3) Add the hydrothermal solution to the reactor and place the titanium substrate material in the hydrothermal solution. Heat to 220°C and keep warm for 2 hours to complete the hydrothermal deposition of sodium titanate.
[0060] 4) Remove the sample, rinse it with water, and keep it in a 40℃ oven for 30 minutes to obtain a sodium titanate coating;
[0061] 5) Dissolve 0.1 mol / L barium hydroxide octahydrate Ba(OH)2·8H2O in water and stir until the solution becomes transparent for later use;
[0062] 6) Add the hydrothermal solution to the reactor, and place the titanium substrate material coated with sodium titanate into the hydrothermal solution. Heat to 150°C and keep warm for 3 hours to complete the hydrothermal deposition of barium titanate.
[0063] 7) After the hydrothermal deposition is completed, take out the sample, rinse it with water, keep it in the oven at 40℃ for 15 min, then soak it in 0.01 mol / L glacial acetic acid for 6 min, take out the sample, rinse it with water, and keep it in the oven at 70℃ for 25 min to obtain the barium titanate BaTiO3 coating on the surface of the titanium substrate.
[0064] 8) Prepare norepinephrine-Tris-HCl buffer solution: At room temperature, dissolve 0.8 mol / L Tris-HCl in water and add 0.02 g of norepinephrine to prepare a buffer solution. Stir until the solution is transparent and set aside.
[0065] 9) Place the titanium substrate material with barium titanate coating in norepinephrine-Tris-HCl buffer solution, stir for 12 h, take out the sample, rinse it with water, and keep it in a 40℃ oven for 30 min.
[0066] 10) Preparation of hydrothermal solution: At room temperature, add 0.03 mol / L sodium glycerophosphate (C3H7Na2O6P) and 0.3 mol / L calcium disodium ethylenediaminetetraacetate (C6P). 10 H 12 Prepare a hydrothermal solution of CaN2Na2O8 by adjusting the pH to 10-11 with 0.5 mol / L sodium hydroxide (NaOH).
[0067] 11) Add the prepared hydrothermal solution to the reactor, place the titanium substrate in the hydrothermal solution, heat to 140℃, keep warm for 9 hours, and complete the hydrothermal deposition;
[0068] 12) Post-treatment: After hydrothermal deposition, the sample is taken out, rinsed with water, and kept in an oven at 60℃ for 20 minutes to obtain a barium titanate-hydroxyapatite coating on the surface of the titanium substrate.
[0069] Tests revealed that nanorod-shaped hydroxyapatite precipitated on the surface of the titanium substrate material, with a particle size of 120~140nm.
[0070] Example 2
[0071] 1) Polish the titanium substrate material with 1000# and 4000# sandpaper until there are no spiral marks. Then place it in acetone, alcohol, deionized water and alcohol solution respectively for ultrasonic cleaning for 15 minutes to remove surface dirt. Let it air dry to obtain titanium substrate.
[0072] 2) Dissolve 0.8 mol / L sodium hydroxide (NaOH) in water to prepare a hydrothermal solution, and stir until the solution becomes transparent for later use;
[0073] 3) Add the hydrothermal solution to the reactor and place the titanium substrate in the hydrothermal solution. Heat to 210°C and keep warm for 2 hours to complete the hydrothermal deposition of sodium titanate.
[0074] 4) Remove the sample, rinse it with water, and keep it in a 60℃ oven for 20 minutes to obtain a sodium titanate coating;
[0075] 5) Dissolve 0.2 mol / L barium hydroxide octahydrate Ba(OH)2·8H2O in water and stir until the solution becomes transparent for later use;
[0076] 6) Add the hydrothermal solution to the reactor, place the titanium substrate material in the hydrothermal solution, heat to 140℃, and keep warm for 3 hours to complete the hydrothermal deposition of barium titanate;
[0077] 7) After the hydrothermal deposition is completed, the sample is taken out, rinsed with water, and kept in an oven at 60℃ for 20 min. Then, it is soaked in 0.01 mol / L glacial acetic acid for 5 min. The sample is then taken out, rinsed with water, and kept in an oven at 60℃ for 30 min to obtain a barium titanate (BaTiO3) coating on the surface of the titanium substrate.
[0078] 8) Prepare norepinephrine-Tris-HCl buffer solution: At room temperature, dissolve 0.5 mol / L Tris-HCl in water and add 0.01 g of norepinephrine to prepare a buffer solution. Stir until the solution is transparent and set aside.
[0079] 9) Place the titanium substrate material with barium titanate coating in norepinephrine-Tris-HCl buffer solution, stir for 12 h, take out the sample, rinse it with water, and keep it in a 50℃ oven for 25 min.
[0080] 10) Preparation of hydrothermal solution: At room temperature, add 0.02 mol / L sodium glycerophosphate (C3H7Na2O6P) and 0.2 mol / L calcium disodium ethylenediaminetetraacetate (C6P). 10 H 12 Prepare a hydrothermal solution using CaN2Na2O8 and 0.5 mol / L sodium hydroxide (NaOH) to adjust the pH to 8-9.
[0081] 11) Add the hydrothermal solution to the reactor, and place the titanium substrate material treated with buffer solution in the hydrothermal solution. Heat to 150°C and keep warm for 12 hours to complete the hydrothermal deposition.
[0082] 12) Post-treatment: After hydrothermal deposition, the sample is taken out, rinsed with water, and kept in an oven at 40℃ for 25 minutes to obtain a barium titanate-hydroxyapatite coating on the surface of the titanium substrate.
[0083] Tests revealed that nanorod-shaped hydroxyapatite precipitated on the surface of the titanium substrate material, with a particle size of 120~140nm.
[0084] Example 3
[0085] 1) Polish the titanium substrate material with 1000# and 4000# sandpaper until there are no spiral marks. Then place it in acetone, alcohol, deionized water and alcohol solution respectively for ultrasonic cleaning for 20 minutes to remove surface dirt. Let it air dry to obtain titanium substrate.
[0086] 2) Dissolve 0.5 mol / L sodium hydroxide (NaOH) in water to prepare a hydrothermal solution, and stir until the solution becomes transparent for later use;
[0087] 3) Add the hydrothermal solution to the reactor and place the titanium substrate material in the hydrothermal solution. Heat to 200°C and keep warm for 2 hours to complete the hydrothermal deposition of sodium titanate.
[0088] 4) Remove the sample, rinse it with water, and keep it in a 50℃ oven for 25 minutes to obtain a sodium titanate Na2TiO3 coating.
[0089] 5) Dissolve 0.3 mol / L barium hydroxide octahydrate Ba(OH)2·8H2O in water and stir until the solution becomes transparent for later use;
[0090] 6) Add the hydrothermal solution to the reactor, and place the titanium substrate material coated with sodium titanate into the hydrothermal solution. Heat to 160°C and keep warm for 3 hours to complete the hydrothermal deposition of barium titanate.
[0091] 7) After the hydrothermal deposition is completed, take out the sample, rinse it with water, keep it in the oven at 50℃ for 30 min, then soak it in 0.01 mol / L glacial acetic acid for 10 min, take out the sample again, rinse it with water, and keep it in the oven at 80℃ for 25 min to obtain the barium titanate BaTiO3 coating on the surface of the titanium substrate.
[0092] 8) Prepare norepinephrine-Tris-HCl buffer solution: At room temperature, dissolve 1 mol / L Tris-HCl in water and add 0.015 g of norepinephrine to prepare a buffer solution. Stir until the solution is transparent and set aside.
[0093] 9) Place the titanium substrate material with barium titanate coating in norepinephrine-Tris-HCl buffer solution, stir for 12 h, take out the sample, rinse it with water, and keep it in a 60℃ oven for 20 min.
[0094] 10) Preparation of hydrothermal solution: At room temperature, add 0.01 mol / L sodium glycerophosphate (C3H7Na2O6P) and 0.1 mol / L calcium disodium ethylenediaminetetraacetate (C6P). 10 H 12 CaN2Na2O8, with pH adjusted to 8-9 using 1mol / L sodium hydroxide (NaOH), is used to prepare a hydrothermal solution.
[0095] 11) Add the hydrothermal solution to the reactor, and place the titanium substrate material treated with buffer solution in the hydrothermal solution. Heat to 160°C and keep warm for 6 hours to complete the hydrothermal deposition.
[0096] 12) Post-treatment: After hydrothermal deposition, the sample is taken out, rinsed with water, and kept in an oven at 50℃ for 30 minutes to obtain a barium titanate-hydroxyapatite coating on the surface of the titanium substrate.
[0097] Tests revealed that nanorod-shaped hydroxyapatite precipitated on the surface of the titanium substrate material, with a particle size of 140~160nm.
[0098] The following section describes a scratch detection test performed on the composite coating prepared by the method of this invention.
[0099] BaTiO3-Ca with a thickness of approximately 1.5 μm was prepared using the above hydrothermal process. 10 BaTiO3-Ca is formed by three hydrothermal reactions using (PO4)6OH2 coating as the basic unit. 10 The (PO4)6OH2 composite coating exhibits good surface quality. Simulated testing was conducted using diamond as a friction element under a scratch tester. (BaTiO3-Ca) 10When the (PO4)6OH2 coating surface is subjected to gradually increasing forces, ranging from 0N to 40N, and with a scratch length of 4mm, minor scratches appear at approximately 3.1mm, indicating coating cracking. However, no severe wear or abrasion occurs overall. Figure 3a , 3b As shown, the coating exhibits good adhesion, verifying the prepared BaTiO3-Ca... 10 The (PO4)6OH2 coating exhibits good adhesion under impact load, with no peeling or other phenomena, demonstrating excellent coating adhesion performance.
[0100] From Figure 3a, Figure 3b It can be seen that the bio-coated composite material prepared by the present invention has a good coating adhesion. The adhesion strength of the bio-coated composite material is approximately greater than or equal to 30 N, while the adhesion strength of most other bio-coated composite materials is 25 N. It can be seen that the bio-coated composite material prepared by the present invention not only has good coating adhesion and is not easy to fall off, but also has characteristics such as biocompatibility, bioactivity and a certain piezoelectric stimulation response.
[0101] Figure 1 , Figure 2 The surface morphology and cross-sectional morphology of the barium titanate-hydroxyapatite coating prepared on the surface of a titanium substrate are shown respectively. Figure 1 and Figure 2 As can be seen, the coating prepared by this method has a dense nanocolumnar structure, which is firmly bonded to the substrate. It can effectively solve the problems of biocompatibility and piezoelectric properties of titanium surface, achieve good adhesion to bone tissue surface, significantly promote osteogenic function of cells, and facilitate the implantation of substrate materials.
[0102] This invention is not limited to the above embodiments. Based on the technical solutions disclosed in this invention, those skilled in the art can make some substitutions and modifications to some of the technical features without creative effort, and all such substitutions and modifications are within the protection scope of this invention.
Claims
1. A method for preparing a barium titanate-hydroxyapatite coating based on a titanium substrate, characterized in that, include: The titanium substrate is ground and polished, ultrasonically cleaned, and treated with natural wind. The pretreated titanium substrate was placed in a sodium hydroxide hydrothermal solution, heated to 200~220℃, and kept at that temperature for 2 hours to complete the sodium titanate hydrothermal deposition. The titanium substrate after hydrothermal deposition of sodium titanate was rinsed, dried, and kept warm to obtain a sodium titanate coating on the surface of the titanium substrate. A titanium substrate coated with sodium titanate was placed in a hydrothermal solution of barium hydroxide octahydrate, heated to 140-160°C, and held for 3 hours to complete the hydrothermal deposition of barium titanate. The titanium substrate after barium titanate hydrothermal deposition is rinsed, dried, kept warm, and then acid-soaked. This process is repeated to obtain a sodium titanate-barium titanate coating on the surface of the titanium substrate. The titanium substrate coated with sodium titanate-barium titanate was placed in norepinephrine-Tris-HCl buffer solution, stirred, removed, rinsed, dried, and kept warm. The titanium substrate treated with buffer solution was placed in a hydrothermal solution of sodium glycerophosphate-disodium calcium ethylenediaminetetraacetate and heated to 140-160℃ for 6-12 hours to complete the hydrothermal deposition of hydroxyapatite. The titanium substrate after hydrothermal deposition of hydroxyapatite was rinsed, dried, and kept warm to obtain a barium titanate-hydroxyapatite coating on the surface of the titanium substrate.
2. The method for preparing a barium titanate-hydroxyapatite coating based on a titanium substrate according to claim 1, characterized in that, The titanium substrate material was polished with 1000# and 4000# sandpaper until it was smooth and without threads. Then it was ultrasonically cleaned in acetone, deionized water and alcohol solutions for 10-20 minutes each.
3. The method for preparing a barium titanate-hydroxyapatite coating based on a titanium substrate according to claim 1, characterized in that, The molar concentration of the sodium hydroxide hydrothermal solution is 0.5~1 mol / L; The molar concentration of the hydrothermal solution of barium hydroxide octahydrate is 0.1~0.3 mol / L.
4. The method for preparing a barium titanate-hydroxyapatite coating based on a titanium substrate according to claim 1, characterized in that, Acid soaking involves immersing the sample in an acetic acid solution with a molar concentration of 0.01 mol / L for 5-10 minutes.
5. The method for preparing a barium titanate-hydroxyapatite coating based on a titanium substrate according to claim 1, characterized in that, The buffer solution was prepared by mixing 0.01-0.02 g of norepinephrine with 0.5-1 mol / L Tris-HCl solution and stirring for 12-16 h.
6. The method for preparing a barium titanate-hydroxyapatite coating based on a titanium substrate according to claim 1, characterized in that, The hydrothermal solution of sodium glycerophosphate-disodium calcium ethylenediaminetetraacetate is prepared by dissolving sodium glycerophosphate (0.01~0.03 mol / L) and disodium calcium ethylenediaminetetraacetate (0.1~0.3 mol / L) in water, adjusting the pH to 8~11 with 0.5~1 mol / L sodium hydroxide, and then mixing them together.
7. The method for preparing a barium titanate-hydroxyapatite coating based on a titanium substrate according to claim 1, characterized in that, After sodium titanate hydrothermal deposition, the titanium substrate is rinsed with water, dried at 40~60℃, and kept warm for 20~30 minutes.
8. The method for preparing a barium titanate-hydroxyapatite coating based on a titanium substrate according to claim 1, characterized in that, After hydrothermal deposition of barium titanate, the titanium substrate is rinsed with water, dried at 40-60℃, kept warm for 15-30 minutes, then soaked in glacial acetic acid for 5-10 minutes, rinsed with water again, dried at 60-80℃, and kept warm for 20-30 minutes.
9. The method for preparing a barium titanate-hydroxyapatite coating based on a titanium substrate according to claim 1, characterized in that, The titanium substrate after hydrothermal deposition of hydroxyapatite is rinsed with water, dried at 40-60℃, and kept warm for 20-30 minutes.
10. A barium titanate-hydroxyapatite coating based on a titanium substrate prepared by the method according to any one of claims 1 to 9, characterized in that, The barium titanate-hydroxyapatite coating is a dense nanocolumnar structure that can adhere to the surface of bone tissue and has piezoelectric properties and biocompatibility.