阅读说明：本技术 具有抗菌纳米多孔铜锌涂层的钛合金及制备方法与应用 (Titanium alloy with antibacterial nano-porous copper-zinc coating, and preparation method and application thereof ) 是由 佟鑫 李垚鑫 王小健 李卫 于 2020-06-18 设计创作，主要内容包括：本发明涉及金属材料表面改性技术领域,公开了一种具有抗菌纳米多孔铜锌涂层的钛合金及制备方法与应用。本发明制备方法包括以下步骤：(1)采用共电沉积法在钛合金基体表面沉积铜锌两种金属,热处理得到含有铜锌涂层的钛合金；(2)将步骤(1)得到的含有铜锌涂层的钛合金用复合酸进行脱合金处理,得到具有抗菌纳米多孔铜锌涂层的钛合金。本发明的制备方法工艺简单,得到具有多孔铜锌涂层的钛合金,其纳米多孔的形貌增大植入物比表面积,提高抗菌剂利用率,同时铜锌的协同抗菌效应极大地提高了钛合金植入物的抗菌性能,具有广谱的抗菌效果,对超级耐药细菌耐甲氧西林金黄色葡萄球菌同样具有抑制作用,在制备医疗器械等领域具有良好的应用前景。(The invention relates to the technical field of metal material surface modification, and discloses a titanium alloy with an antibacterial nano-porous copper-zinc coating, and a preparation method and application thereof. The preparation method comprises the following steps: (1) depositing copper and zinc on the surface of a titanium alloy substrate by adopting a co-electrodeposition method, and carrying out heat treatment to obtain a titanium alloy containing a copper-zinc coating; (2) and (2) performing dealloying treatment on the titanium alloy containing the copper-zinc coating obtained in the step (1) by using composite acid to obtain the titanium alloy with the antibacterial nano porous copper-zinc coating. The preparation method provided by the invention is simple in process, the titanium alloy with the porous copper-zinc coating is obtained, the specific surface area of the implant is increased due to the shape of the nano-pores, the utilization rate of the antibacterial agent is improved, meanwhile, the antibacterial performance of the titanium alloy implant is greatly improved due to the synergistic antibacterial effect of copper and zinc, the titanium alloy implant has a broad-spectrum antibacterial effect, has an inhibiting effect on super drug-resistant bacteria methicillin-resistant staphylococcus aureus, and has a good application prospect in the fields of medical instrument preparation and the like.)

1. A preparation method of titanium alloy with an antibacterial nano-porous copper-zinc coating is characterized by comprising the following steps:

(1) depositing copper and zinc on the surface of a titanium alloy substrate by adopting a co-electrodeposition method, and carrying out heat treatment to obtain a titanium alloy containing a copper-zinc coating;

(2) and (2) performing dealloying treatment on the titanium alloy containing the copper-zinc coating obtained in the step (1) by using composite acid to obtain the titanium alloy with the antibacterial nano porous copper-zinc coating.

2. The method for preparing the titanium alloy with the antibacterial nano-porous copper-zinc coating according to claim 1, characterized in that: in the step (1), the material of the titanium alloy matrix comprises at least one of pure titanium, Ti6Al4V titanium alloy, Ti-6Al-7Nb titanium alloy and Ti-2Al-2.5Zr titanium alloy; the heat treatment time in the step (1) is 1min-24 h; the temperature of the heat treatment is 400-600 ℃.

3. The method for preparing the titanium alloy with the antibacterial nano-porous copper-zinc coating according to claim 1, characterized in that: the co-electrodeposition method in the step (1) specifically comprises the following steps: connecting a titanium alloy matrix and a conductive substrate, connecting the titanium alloy matrix and the conductive substrate to a power supply cathode, connecting an inert anode to a power supply anode, placing the inert anode and a reference electrode together in a solution containing salt of two metal cations of copper and zinc and a complexing agent, wherein the reference electrode is not communicated with a cathode and an anode, turning on a direct current power supply, and codeposition by adopting a fixed potential.

4. The method for preparing the titanium alloy with the antibacterial nano-porous copper-zinc coating according to claim 1, characterized in that: in the step (2), the concentration of the composite acid is 15-45 wt%; the composite acid is composed of two or more of hydrochloric acid, nitric acid and sulfuric acid.

5. The method for preparing the titanium alloy with the antibacterial nano-porous copper-zinc coating according to claim 4, characterized in that: in the composite acid, the concentration of hydrochloric acid is 5-20 wt%, the concentration of sulfuric acid is 10-40 wt%, and the concentration of nitric acid is 10-30 wt%.

6. The method for preparing the titanium alloy with the antibacterial nano-porous copper-zinc coating according to claim 1, characterized in that: the dealloying treatment in the step (2) is carried out at 50-70 ℃; the dealloying time is 8-16 h.

7. The method for preparing the titanium alloy with the antibacterial nano-porous copper-zinc coating according to claim 3, characterized in that: the concentrations of copper ions and zinc ions in the salt solution containing copper cations and zinc cations are respectively 0.01-1 mol/L;

the complex comprises at least one of citrate, tartaric acid, tartrate and pyrophosphate; the concentration range of the complex in the solution is 0.1-5 mol/L.

8. The method for preparing the titanium alloy with the antibacterial nano-porous copper-zinc coating according to claim 3, characterized in that: the codeposition time is 10-60 min.

9. Titanium alloy with an antibacterial nanoporous copper zinc coating, characterized in that it is obtained by the preparation method according to any one of claims 1 to 8.

10. Use of the titanium alloy with an antibacterial nanoporous copper zinc coating as claimed in claim 9 in the field of the preparation of medical devices.

Technical Field

The invention relates to the technical field of metal material surface modification, in particular to a titanium alloy with an antibacterial nano-porous copper-zinc coating, and a preparation method and application thereof.

Background

The 3D printing is a special processing technology that is rapidly developed in recent years, and an object is constructed by processing and printing bondable materials such as metal powder or plastic layer by layer through digital model design. With the development and gradual maturity of the 3D printing technology, the unique processing method can design a complex structure to realize customized service, has the advantages of high material utilization rate, high forming speed and the like, and has great attention in the field of medical implants.

Titanium alloy implants are widely applied to clinical treatment due to good mechanical properties and biocompatibility, however, titanium alloys are often sensitive to bacterial adhesion and are easy to cause bacterial infection, so that premature failure of implants can be caused, even revision surgery has to be performed, and great pain is brought to patients. Therefore, the preparation of the antibacterial titanium alloy has important significance, wherein the nano silver particles become the main selection for preparing the antibacterial titanium alloy at present due to the advantages of strong antibacterial effect, good thermal stability and the like. For example, CN109453425A discloses a method for forming a composite antibacterial coating carrying HA/Ag/Cs by performing alkali heat treatment and dopamine activation on a titanium alloy surface, performing ultraviolet irradiation to deposit Ag particles on the basis of HA grafting, and coating with chitosan; CN102758202A discloses a method for preparing a silver-loaded titanium nanotube array by anodic oxidation technology and improving the long-term antibacterial ability of an implant by micro-arc oxidation. The silver nanoparticles have good antibacterial effect, but may also cause adverse reaction to normal cells of a human body. Research proves that the silver nanoparticles can destroy cell membranes, induce generation of genetic toxins and cytotoxins, damage human lung fibrous tissues and glioma cells, and even inhibit the human immune system. It has also been shown that the cytotoxicity of silver nanoparticles depends on the amount and size of the particles. In conclusion, the biological safety of silver nanoparticles is more controversial, the toxicity mechanism is not clear, and further extensive research is needed to verify the biological safety.

Therefore, the development of the antibacterial titanium alloy with high safety, broad-spectrum antibacterial performance, simple process and low cost has important significance for the application of the titanium alloy implant in the field of preparing medical instruments.

Disclosure of Invention

In order to overcome the defects of the prior art, the invention mainly aims to provide a preparation method of a titanium alloy with an antibacterial nano-porous copper-zinc coating.

The invention also aims to provide the titanium alloy with the antibacterial nano-porous copper-zinc coating prepared by the method.

The invention further aims to provide application of the titanium alloy with the antibacterial nano-porous copper-zinc coating in the field of preparation of medical instruments and the like.

In order to achieve the purpose, the invention adopts the following technical scheme:

a preparation method of a titanium alloy with an antibacterial nano-porous copper-zinc coating comprises the following steps:

(1) depositing copper and zinc on the surface of a titanium alloy substrate by adopting a co-electrodeposition method, and carrying out heat treatment to obtain a titanium alloy containing a copper-zinc coating;

(2) and (2) performing dealloying treatment on the titanium alloy containing the copper-zinc coating obtained in the step (1) by using composite acid to obtain the titanium alloy with the antibacterial nano porous copper-zinc coating.

In the step (1), the material of the titanium alloy matrix may include at least one of pure titanium, Ti6Al4V titanium alloy, Ti-6Al-7Nb titanium alloy, Ti-2Al-2.5Zr titanium alloy, and the like. The titanium alloy substrate can be prepared by 3D printing. The 3D printing preferably adopts a selective area melting laser additive technology.

In the step (1), the titanium alloy substrate is preferably subjected to surface treatment to remove a surface oxide layer and undissolved particles. The surface treatment mode comprises at least one of pickling solution cleaning, sand blasting, sand paper grinding and polishing and the like.

In the step (1), the heat treatment time is 1min-24h, preferably 3min-12 h. The temperature of the heat treatment is 400-600 ℃, and preferably 500 ℃.

In the step (1), the co-electrodeposition method specifically comprises the following steps: connecting a titanium alloy matrix and a conductive substrate, connecting the titanium alloy matrix and the conductive substrate to a power supply cathode, connecting an inert anode to a power supply anode, placing the inert anode and a reference electrode together in a solution containing salt of two metal cations of copper and zinc and a complexing agent, wherein the reference electrode is not communicated with a cathode and an anode, turning on a direct current power supply, and codeposition by adopting a fixed potential.

Preferably, the conductive substrate is a conductive substrate conventionally used in the art, and may include at least one of a stainless steel plate, a metal plate with good conductivity, or other materials plated with a conductive layer.

Preferably, the inert anode is an anode conventionally used in the art, such as a platinum sheet electrode, a graphite electrode, and the like.

Preferably, the reference electrode is an electrode conventionally used in the art, such as a hydrogen electrode, a calomel electrode, a silver/silver chloride electrode, and the like.

Preferably, the concentrations of copper ions and zinc ions in the salt solution containing copper cations and zinc cations are the same or different and are respectively 0.01-1 mol/L.

Preferably, the complex may include at least one of citrate, tartaric acid, tartrate, pyrophosphate, and the like. The concentration range of the complex in the solution is 0.1-5 mol/L.

Preferably, the voltage range of the direct current power supply is-2V to 5V.

Preferably, the codeposition time is 10-60 min.

In the step (1), the titanium alloy containing the copper-zinc coating is preferably cleaned and dried. The drying temperature is 40-60 ℃, and the drying time is 10-30 min.

In the step (2), the composite acid may be composed of two or more of hydrochloric acid, nitric acid, sulfuric acid, and the like. The concentration of the complex acid is preferably 15 to 45 wt%. In the composite acid, the concentration of hydrochloric acid is preferably 5 to 20 wt%, the concentration of sulfuric acid is preferably 10 to 40 wt%, and the concentration of nitric acid is preferably 10 to 30 wt%.

In the step (2), the dealloying treatment is preferably performed at 50 to 70 ℃. The dealloying time is 8-16 h.

The titanium alloy after the dealloying treatment in the step (2) is preferably washed with water or absolute ethyl alcohol and dried.

The invention also provides the titanium alloy with the antibacterial nano-porous copper-zinc coating prepared by the method. According to the invention, the co-electrodeposition method is adopted to co-deposit two metals of copper and zinc on the surface of the titanium alloy, and the composite acid is used for dealloying treatment, so that the titanium alloy with the antibacterial nano-porous copper-zinc coating is obtained, has a broad-spectrum antibacterial bacteriostatic effect, especially has a strong inhibitory effect on super drug-resistant bacteria methicillin-resistant staphylococcus aureus (MRSA), and has a good application prospect in the fields of medical instrument preparation and the like.

Compared with the prior art, the invention has the following advantages and beneficial effects:

(1) copper and zinc are all trace elements necessary for human bodies, have broad-spectrum antibacterial property, have strong bactericidal effect on gram-positive bacteria and gram-negative bacteria, and have the characteristic of difficult generation of drug resistance after long-term use. The copper and zinc elements can play a role in synergistic antibacterial action, and particularly show a strong inhibition effect on the MRSA (super drug-resistant bacteria); meanwhile, the combination of copper and zinc can reduce the usage amount of single metal and reduce the possibility of harm caused by excessive metal in organisms. Furthermore, the coating formed by the co-electrodeposition has strong binding force, can achieve a long-term antibacterial effect, and solves the problem of insufficient antibacterial function of the surface of the titanium alloy implant. The copper and zinc have the function of promoting osteogenesis while playing an antibacterial role, and the raw materials are low in price and rich in resources, so that the production cost is reduced.

(2) According to the invention, the copper-zinc coating on the surface of the titanium alloy is subjected to dealloying treatment by adopting the medium-concentration composite acid, so that the nano-porous copper-zinc coating is obtained, the selection of the type and the concentration ratio of the composite acid is an important part in the preparation process, the hydrochloric acid and the sulfuric acid have a selective corrosion effect on the copper-zinc coating under the appropriate concentration ratio, the adverse effects of high-concentration acid treatment on the reduction of the strength of a base material and the improvement of brittleness are avoided, and finally, a copper-zinc nano-porous structure with firm combination and excellent mechanical properties is formed. The micronized nano porous structure increases the specific surface area of the copper-zinc coating, improves the antibacterial utilization rate of copper-zinc ions and enhances the biological functionality of the copper-zinc ions. Meanwhile, the rough and porous structure is more beneficial to the combination of the titanium alloy implant and tissues, thereby improving the biocompatibility of the titanium alloy implant. Cu is prepared by controlling the dealloying reaction time, the temperature and other conditions_nZn_1-nThe proportion of copper and zinc in the nano porous coating can be regulated and controlled by adjusting reaction conditions of the nano porous coating. Compared with a single element coating, the synergistic antibacterial effect of the copper and the zinc greatly enhances the antibacterial function of the titanium alloy implant.

(3) The invention adopts the co-electrodeposition method to prepare the copper-zinc coating on the surface of the titanium alloy, is not limited by the shape and the structure of the titanium alloy matrix, can uniformly form the copper-zinc coating on the surface of the titanium alloy matrix, has simple process and mild conditions, and can be applied to large-scale production.

Drawings

Fig. 1 is a scanning electron microscope image of 3D printing of a titanium alloy nanoporous copper coating in comparative example 1.

Fig. 2 is a graph of the energy spectrum analysis of the 3D printed titanium alloy nanoporous copper coating in comparative example 1.

FIG. 3 is a scanning electron microscope image of 3D printing of the titanium alloy nanoporous Cu-Zn coating in example 1.

Fig. 4 is a composition analysis diagram of the 3D printed titanium alloy nanoporous copper zinc coating in example 1.

Detailed Description

The present invention will be described in further detail with reference to examples, but the embodiments of the present invention are not limited thereto. All the raw materials and reagents used in the present invention are commercially available raw materials and reagents, unless otherwise specified.

Comparative example 1: preparation of 3D printing titanium alloy substrate

Selecting Ti6Al4V powder, preparing a matrix by a selective area laser melting additive manufacturing method, pickling for surface treatment, wherein the pickling solution is a mixed aqueous solution of hydrofluoric acid and nitric acid, the concentration of the hydrofluoric acid is 2 wt%, and the concentration of the nitric acid is 3 wt%.

Comparative example 2: preparation of 3D printing titanium alloy with nano porous copper coating

(1) Selecting Ti6Al4V powder, preparing a matrix by a selective area laser melting additive manufacturing method, pickling for surface treatment, wherein the pickling solution is a mixed aqueous solution of hydrofluoric acid and nitric acid, the concentration of the hydrofluoric acid is 2 wt%, and the concentration of the nitric acid is 3 wt%. Then connecting the titanium alloy matrix after surface treatment with a conductive substrate, connecting the titanium alloy matrix with the conductive substrate, connecting a power supply cathode (stainless steel plate), connecting an inert anode (graphite electrode) with the power supply anode, and putting the inert anode and a reference electrode (Ag/AgCl electrode) into a solution containing salts of copper and zinc cations and a complexing agent (the solution comprises 0.02mol/L CuSO)₄·5H₂O，0.2mol/L ZnSO₄·7H₂O, 0.5mol/L aqueous solution of sodium citrate), and the reference electrode is not communicated with the cathode and the anode, a direct current power supply is switched on, two metals of copper and zinc are codeposited for 10min by adopting a fixed potential of-1.2V (compared with the reference electrode), the titanium alloy is taken out, dried for 10min at 60 ℃, and annealed for 3min at 500 ℃ to obtain the titanium alloy containing the copper-zinc coating;

(2) and (2) immersing the titanium alloy containing the copper-zinc coating obtained in the step (1) into a composite acid solution (containing 10 wt% of sulfuric acid and 13.7 wt% of hydrochloric acid solution), starting a dealloying reaction at 60 ℃, washing the titanium alloy with water and absolute ethyl alcohol respectively for 24 hours, and drying to obtain the 3D printing titanium alloy with the nano-porous copper coating.

Fig. 1 is a scanning electron microscope image of the 3D-printed titanium alloy nanoporous copper coating in this embodiment, which can observe large areas of ligaments and uniform nanoporous structures in cavities, and the high specific surface area can be in close contact with bacteria, thereby improving the antibacterial utilization rate of copper ions and enhancing the biological functionality.

Fig. 2 is a graph of energy spectrum analysis of the 3D-printed titanium alloy nanoporous copper coating in this example, and the result shows that the copper-zinc coating prepared by co-electrodeposition removes more active zinc elements through complete dealloying reaction, which proves that the coating is a nanoporous copper coating.