Preparation method of a medical magnesium alloy material

Abstract

The present invention provides a preparation method of a medical magnesium alloy material, belonging to the technical field of medical auxiliary instruments. Among them, the method includes the following steps: pretreating to obtain a magnesium alloy wire with a target texture; performing chemical deposition treatment on the magnesium alloy wire to form a first composite layer on the surface of the magnesium alloy wire to obtain a first magnesium alloy composite material; immersing the first magnesium alloy composite material in an aqueous solution containing amino groups to make the first composite layer combine with the amino groups to form a second composite layer to obtain a second magnesium alloy composite material; performing surface modification treatment on the second magnesium alloy composite material to make the second magnesium alloy composite material form a third composite layer containing target functional groups to obtain a target magnesium alloy composite material. The preparation method of the magnesium alloy provided by the present invention can utilize the combination of functional groups and amino groups in the second composite layer to form condensates and peptide bonds, which is beneficial to enhancing the affinity between the magnesium alloy suture and human tissues and promoting wound healing.

Description

Technical Field

[0001] This application relates to the technical field of medical auxiliary devices, and particularly to a preparation method of a medical magnesium alloy material. Background Art

[0002] Magnesium alloy medical surgical sutures are a new type of medical suture. They have excellent biocompatibility, biodegradability, and mechanical properties, and are widely used in various surgical sutures. The material selection of magnesium alloy medical surgical sutures is very important, and magnesium alloy materials with good biocompatibility and biodegradability need to be selected.

[0003] Due to the active chemical properties of magnesium alloys, after the suture operation is completed, the too-fast corrosion and degradation rate of the magnesium alloy itself will lead to the accelerated degradation of its own medical properties (including properties such as biocompatibility, tensile strength, or stiffness), affecting the normal healing of the sutured wound and being not conducive to the aesthetic effect of wound recovery. Summary of the Invention

[0004] In view of this, the purpose of this application is to propose a preparation method of a medical magnesium alloy material to improve the problem that magnesium alloy sutures are easily corroded after surgery and affect their medical properties in the prior art.

[0005] Based on the above purpose, this application provides a preparation method of a medical magnesium alloy material, including the following steps:

[0006] Pre-treat to obtain magnesium alloy wire rods with a target tissue texture;

[0007] Perform chemical deposition treatment on the magnesium alloy wire rods to form a first composite layer on the surface of the magnesium alloy wire rods, obtaining a first magnesium alloy composite material;

[0008] Immerse the first magnesium alloy composite material in an aqueous solution containing amino groups, so that the first composite layer combines with the amino groups to form a second composite layer, obtaining a second magnesium alloy composite material;

[0009] Perform surface modification treatment on the second magnesium alloy composite material to form a third composite layer containing target functional groups on the second magnesium alloy composite material, obtaining a target magnesium alloy composite material; the target functional groups include at least one of hydroxyl, carboxyl, and carbonyl.

[0010] Furthermore, the aqueous solution of amino groups is a diammonium hydrogen phosphate solution.

[0011] Furthermore, the step of immersing the first magnesium alloy composite material in an aqueous solution containing amino groups, so that the first composite layer combines with the amino groups to form a second composite layer, obtaining a second magnesium alloy composite material, includes:

[0012] Polish the first magnesium alloy composite material and prepare a diammonium hydrogen phosphate solution with a preset concentration;

[0013] Immerse the polished first magnesium alloy composite material in a diammonium hydrogen phosphate solution at a solution temperature of 80 °C, and let it stand for 30 - 60 minutes after immersion to obtain a second magnesium alloy material.

[0014] Furthermore, the step of immersing the first magnesium alloy composite material in an aqueous solution containing an amino group to cause the first composite layer to combine with the amino group to form a second composite layer to obtain a second magnesium alloy composite material includes:

[0015] Polish the first magnesium alloy composite material, prepare a mixed solution of diammonium hydrogen phosphate and calcium chloride, and adjust the pH value of the mixed solution of diammonium hydrogen phosphate and calcium chloride to 6.3 - 6.5;

[0016] Immerse the polished first magnesium alloy composite material in the mixed solution of diammonium hydrogen phosphate and calcium chloride at a solution temperature of 85 °C, and let it stand for 30 - 60 minutes after immersion to obtain a second magnesium alloy material.

[0017] Furthermore, the step of immersing the first magnesium alloy composite material in an aqueous solution containing an amino group to cause the first composite layer to combine with the amino group to form a second composite layer to obtain a second magnesium alloy composite material includes:

[0018] Polish the first magnesium alloy composite material, prepare a mixed solution of diammonium hydrogen phosphate and calcium chloride, and adjust the pH value of the mixed solution of diammonium hydrogen phosphate and calcium chloride to 6.3 - 6.5;

[0019] Immerse the polished first magnesium alloy composite material in the mixed solution of diammonium hydrogen phosphate and calcium chloride at a solution temperature of 85 °C, and let it stand for 30 - 60 minutes after immersion;

[0020] Dissolve polycaprolactone in an organic solvent to obtain a polycaprolactone solution;

[0021] Immerse the first magnesium alloy composite material soaked in the mixed solution of diammonium hydrogen phosphate and calcium chloride in the polycaprolactone solution, and repeat the lifting for a first preset number of times to obtain a second magnesium alloy composite material.

[0022] Furthermore, the step of immersing the first magnesium alloy composite material in an aqueous solution containing an amino group to cause the first composite layer to combine with the amino group to form a second composite layer to obtain a second magnesium alloy composite material includes:

[0023] Polish the first magnesium alloy composite material, prepare a mixed solution of diammonium hydrogen phosphate and calcium chloride, and adjust the pH value of the mixed solution of diammonium hydrogen phosphate and calcium chloride to 6.3 - 6.5;

[0024] Immerse the polished first magnesium alloy composite material in the mixed solution of diammonium hydrogen phosphate and calcium chloride at a solution temperature of 85 °C, and let it stand for 30 - 60 minutes after immersion;

[0025] Dissolve polycaprolactone in an organic solvent to obtain a polycaprolactone solution;

[0026] Immerse the first magnesium alloy composite material soaked in a mixed solution of diammonium hydrogen phosphate and calcium chloride into the polycaprolactone solution, and repeat the lifting for a second preset number of times to obtain a second magnesium alloy composite material; wherein, the second preset number of times is greater than the first preset number of times.

[0027] Further, the pretreatment to obtain the magnesium alloy wire with the target texture includes:

[0028] Physically extrude and deform the preheated magnesium alloy substrate to form a magnesium alloy wire;

[0029] Obtain a magnesium alloy wire conforming to a preset shape through a rolling or drawing process.

[0030] Further, the first composite layer includes a metal component and a non-metal component, wherein the metal component includes at least one of titanium, tungsten, chromium, or molybdenum, and the non-metal component includes at least one of polymers such as polyester, polypropylene, epoxy resin, or polyhydroxyalkanoate.

[0031] Further, before the chemical deposition treatment of the magnesium alloy wire, it includes:

[0032] Clean and polish the magnesium alloy wire with an alkaline solution, and the roughness of the polished magnesium alloy wire is 2000#;

[0033] Repeat cleaning the polished magnesium alloy wire.

[0034] Further, it also includes:

[0035] Clean the target magnesium alloy material under aseptic conditions and conduct a quality assessment on the target magnesium alloy material. The quality assessment includes physical property detection, chemical property detection, biocompatibility detection, and microbial contamination impact detection of the target magnesium alloy material. Based on the same inventive concept, the present disclosure also provides an electronic device, including a memory, a processor, and a computer program stored on the memory and executable by the processor. When the processor executes the computer program, the above-mentioned method is implemented.

[0036] As can be seen from the above, in the preparation method of the medical magnesium alloy material provided by the present application, the magnesium alloy wire is first subjected to chemical deposition treatment, and a first composite layer is formed on the first magnesium alloy composite material after the chemical deposition treatment. Then, the first composite layer combines with amino groups to form a second composite layer. Since when the surface of the second magnesium alloy composite material is modified, the target functional group combines with amino groups to form a condensate, and further forms a peptide bond, the formed condensate can enhance the affinity between the magnesium alloy material and human tissues and accelerate the healing rate of human wounds. In addition, in the target magnesium alloy composite material after the surface modification treatment, the carbonyl group in the target functional group can undergo a reduction reaction with active substances such as free radicals in human tissues, thereby reducing the oxidative stress reaction in human tissues and improving the tissue damage problem. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions in the present application or related technologies, the following will briefly introduce the drawings required for use in the description of the embodiments or related technologies. Obviously, the drawings in the following description are only the embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0038] Figure 1 Schematic diagram of the electrochemical impedance spectra of the untreated magnesium alloy and the 1# magnesium alloy in a 0.9% NaCl aqueous solution in the embodiment of the present application;

[0039] Figure 2 Schematic diagram of the electrochemical impedance spectra of the untreated magnesium alloy and the 2# magnesium alloy in a 0.9% NaCl aqueous solution in the embodiment of the present application;

[0040] Figure 3 Schematic diagram of the electrochemical impedance spectra of the untreated magnesium alloy and the 3# magnesium alloy in a 0.9% NaCl aqueous solution in the embodiment of the present application;

[0041] Figure 4 Schematic diagram of the electrochemical impedance spectra of the untreated magnesium alloy and the 4# magnesium alloy in a 0.9% NaCl aqueous solution in the embodiment of the present application;

[0042] Figure 5 Schematic diagram of the polarization curves of the untreated magnesium alloy and the magnesium alloy under different surface treatment methods in a 0.9% NaCl aqueous solution in the embodiment of the present application.

[0043] Figure 6 Schematic diagram of the structural hierarchy of the treatment process of the magnesium alloy wire in the embodiment of the present application;

[0044] Figure 7a Schematic diagram of the changes in the wound within one week after suturing the wound with the 1# magnesium alloy material in the embodiment of the present application;

[0045] Figure 7b Schematic diagram of the changes in the wound within one week after suturing with the 2# magnesium alloy material in the embodiment of the present application;

[0046] Figure 7c Schematic diagram of the changes in the wound within one week after suturing with the 3# magnesium alloy material in the embodiment of the present application;

[0047] Figure 7d Schematic diagram of the changes in the wound within one week after suturing with the 4# magnesium alloy material in the embodiment of the present application;

[0048] Figure 7e Schematic diagram of the changes in the wound within one week after suturing with the magnesium alloy material without surface modification treatment in the embodiment of the present application;

[0049] Figure 7f Schematic diagram of the changes in the wound within one week after suturing with the existing ordinary medical surgical suture in the embodiment of the present application. Detailed implementation manners

[0050] To make the objectives, technical solutions and advantages of the present application clearer and more understandable, the present application will be further described in detail below with reference to specific embodiments and the accompanying drawings.

[0051] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present application should have the ordinary meanings understood by those with ordinary skills in the field to which the present application belongs. The "first", "second" and similar terms used in the embodiments of the present application do not represent any order, quantity or importance, but are only used to distinguish different components. The terms such as "including" or "comprising" mean that the elements or objects appearing before this term cover the elements or objects listed after this term and their equivalents, without excluding other elements or objects. The terms such as "connected" or "coupled" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The terms such as "upper", "lower", "left", "right" are only used to represent relative positional relationships, and when the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0052] Magnesium alloy is a metallic material with light weight, high strength, high rigidity, high corrosion resistance and good biocompatibility. Compared with traditional materials such as steel and titanium alloy, magnesium alloy has a lighter weight, higher specific strength and specific stiffness, better biocompatibility and biodegradability. Therefore, magnesium alloy is widely used in the fields of medical devices, biomedical materials and biomedical engineering.

[0053] Suturing with a magnesium alloy medical suture can utilize the degradability of the magnesium alloy material to avoid the risk of secondary surgery for suture removal, reduce the pain and recovery time of patients. Magnesium alloy medical sutures can be widely used in various surgical sutures, including skin sutures, soft tissue sutures, bone sutures, etc. The biocompatibility and biodegradability of magnesium alloy medical sutures make them particularly suitable for surgeries that require long-term suture retention, such as orthopedic surgeries and cardiac surgeries.

[0054] For existing magnesium alloy materials, their biocompatibility is not good, and they are easily affected by external factors, reducing their medical performance.

[0055] Based on the above description, in one or more embodiments of the present application, a preparation method of a magnesium alloy medical material is provided. The following will describe the embodiments of the present application in detail with reference to the accompanying drawings.

[0056] As Figure 6 shown, the preparation method of the magnesium alloy medical material described in the present application includes the following steps:

[0057] Step S11, pre-treat to obtain a magnesium alloy wire with a target tissue texture;

[0058] Step S12, perform chemical deposition treatment on the magnesium alloy wire to form a first composite layer on the surface of the magnesium alloy wire, obtaining a first magnesium alloy composite material;

[0059] Step S13, immerse the first magnesium alloy composite material in an aqueous solution containing amino groups, so that the first composite layer combines with the amino groups to form a second composite layer, obtaining a second magnesium alloy composite material;

[0060] Step S14, perform surface modification treatment on the second magnesium alloy composite material to form a third composite layer containing target functional groups on the second magnesium alloy composite material, obtaining a target magnesium alloy composite material; the target functional groups include at least one of hydroxyl, carboxyl, and carbonyl.

[0061] As can be seen from the above, in the preparation method of the medical magnesium alloy material provided by the present application, first, chemical deposition treatment is performed on the magnesium alloy wire, and a first composite layer is formed on the first magnesium alloy composite material after the chemical deposition treatment. Then, the first composite layer combines with the amino groups to form a second composite layer. Since when the surface of the second magnesium alloy composite material is modified, the target functional groups combine with the amino groups to form a condensate, and further form a peptide bond, the condensate formed after combination can enhance the affinity between the magnesium alloy material and human tissues and accelerate the healing rate of human wounds; in addition, in the target magnesium alloy composite material after the surface modification treatment, the carbonyl in the target functional groups can undergo a reduction reaction with active substances such as free radicals in human tissues, thereby reducing the oxidative stress reaction in human tissues and improving the tissue damage problem.

[0062] It should be noted that the specific application scenarios of the magnesium alloy material in this application are not absolutely limited. This medical magnesium alloy material can be used as a bone implant material, a stent material, or a suture material during surgery. In this regard, the following description in this application will be based on the scenario of using it as a medical magnesium alloy suture.

[0063] In some embodiments, in step S11, the pretreatment process of the magnesium alloy material can be carried out in the following manner:

[0064] Physically extrude and deform the preheated magnesium alloy substrate to form a magnesium alloy wire;

[0065] Obtain magnesium alloy wires that meet the preset shape through rolling or drawing processes.

[0066] In the above embodiments, preheating the magnesium alloy substrate can make it softer and more easily deformable. The preheated magnesium alloy substrate is placed in an extruder, and the magnesium alloy substrate is extruded through an extrusion head to form a magnesium alloy wire; then, magnesium alloy wires with a preset shape are obtained through subsequent rolling or drawing processes. Here, the texture control of the magnesium alloy wire can be achieved by controlling the processing parameters during the preparation process. For example, parameters such as the extrusion speed, extrusion temperature, and extrusion ratio during the extrusion process will affect the texture of the magnesium alloy wire. In addition, subsequent processing such as drawing or rolling can also regulate the texture.

[0067] Exemplarily, the magnesium alloy substrate is selected as AZ31 magnesium alloy, and the obtained magnesium alloy wire after pretreatment is a magnesium alloy wire with a {0001} texture, and its diameter is 0.16 mm. The grain orientation under the {0001} texture is relatively uniform, the surface is smooth, and it is not easy to cause tissue irritation and corrosion. Compared with magnesium alloy wires under other textures, it can have better corrosion resistance and degradability. Of course, when preparing magnesium alloy wires, it is necessary to select a suitable texture according to specific application requirements to ensure its biocompatibility and corrosion resistance. For example, for different human tissues, it is recommended to use sutures with different textures to achieve better clinical application effects.

[0068] It should be noted that when drawing the magnesium alloy wire described in this application, the control accuracy of the total deformation degree of the magnesium alloy wire will be affected by factors such as the drawing speed, lubrication during drawing, and the single-pass deformation degree of drawing. Exemplarily, as shown in Table 1, when drawing with different lubricants, the drawing deformation degree when using soap lubrication is significantly smaller than that when using grease lubrication.

[0069] Table 1 Drawing results of magnesium alloy wires with different lubricants

[0070]

[0071] In some embodiments, the magnesium alloy wire with the target tissue texture can also be obtained by extrusion.

[0072] In some embodiments, preparatory work needs to be done before processing the magnesium alloy wire. Specifically, it includes:

[0073] Clean and polish the magnesium alloy wire with an alkaline solution. The roughness of the polished magnesium alloy wire is 2000#.

[0074] Repeat the cleaning and polishing of the magnesium alloy wire.

[0075] In the above steps, the magnesium alloy wire can also be cleaned by solvent cleaning to remove oil stains and impurities on the surface of the magnesium alloy wire. When polishing the magnesium alloy wire, nano-polishing agent can be used for polishing. Nano-polishing agent is a polishing agent at the micro-particle level, which can form a nano-level flatness on the surface. Apply the nano-polishing agent on the surface of the magnesium alloy and use a polishing machine for polishing. During polishing, the concentration of the polishing agent and the polishing time need to be controlled to avoid surface damage caused by over-polishing. Cleaning the polished magnesium alloy wire again is to clean the surface of the magnesium alloy wire again to remove the residual polishing agent and tiny impurities.

[0076] It should be noted that magnesium alloy has high reactivity and is prone to react with oxygen and moisture in the air, resulting in surface oxidation and corrosion. Therefore, during the cleaning and polishing process, it is necessary to avoid contact with air, and the operation can be carried out in an inert gas environment.

[0077] In some embodiments, in step S12, the chemical deposition treatment of the magnesium alloy wire can be carried out with reference to the following methods:

[0078] a. Meniscus deposition method. The meniscus deposition method is a method of adsorbing liquid molecules on the solid surface, which can form a uniform liquid film, thereby improving the surface wettability and reducing the surface energy. This method can be achieved by soaking, spraying, etc.

[0079] b. Micro-arc plasma deposition method. The micro-arc plasma deposition method is a method that uses high-energy ions to bombard the material surface, causing a chemical reaction on the surface to form a dense oxide film. This method can improve the surface hardness, corrosion resistance and biocompatibility.

[0080] c. Electrochemical deposition method. The electrochemical deposition method is a method of depositing a metal or alloy film on the material surface by using an electrochemical reaction. This method can improve the surface conductivity, corrosion resistance and biocompatibility. By comprehensively applying these surface treatment methods, the surface of the magnesium alloy surgical suture can have better biocompatibility and mechanical properties, thereby improving its application value in the medical field.

[0081] In some embodiments, the first composite layer obtained by the above chemical deposition treatment method includes a metal component and a non-metal component. Among them, the metal component includes at least one of titanium, tungsten, chromium, or molybdenum, and the non-metal component includes at least one of polymers such as polyester, polypropylene, epoxy resin, or polyhydroxyalkanoate.

[0082] Exemplarily, polyester polymers such as polylactic acid and polycaprolactone have good biocompatibility with the human body, can be decomposed and absorbed by the human body, and do not produce toxic reactions; polypropylene polymers such as polyacrylamide and polyacrylic acid also have good biocompatibility with the human body, but they are generally wrapped by the body and will not be degraded and absorbed; epoxy resin polymers have adjustable biocompatibility and bioactivity, so they are widely used in certain specific application scenarios; polyhydroxyalkanoate polymers can also be used as materials for surgical sutures. These materials have high biodegradability and can be completely absorbed by the human body, so there is no obvious damage to human tissues and organs. For different actual application scenarios, the above different polymer materials and metal components can be flexibly chemically deposited onto the magnesium alloy wire.

[0083] It should be noted that in the first composite layer obtained by the chemical deposition treatment provided in this application, the higher the proportion of the metal component, the stronger the stiffness and strength of the magnesium alloy material, but at the same time, the biocompatibility of the magnesium alloy material is reduced. Therefore, it is necessary to determine the proportion of the metal component and the non-metal component in the magnesium alloy material according to different medical needs.

[0084] In some embodiments, in order to obtain the preferred proportion data of the metal component and the non-metal component, several experiments were carried out for comparison. Among them, titanium metal and copper metal were selected as the metal components in the experiment, and epoxy resin was selected as the non-metal component. Titanium metal, copper metal and magnesium alloy were mixed to form the first composite layer with different proportions, and the strength, hardness and biocompatibility of the first composite layer under different proportions were respectively verified to determine the preferred proportion of the metal component and the non-metal component.

[0085] Exemplarily, four different proportions of magnesium alloy and titanium metal mixed samples were set. The proportion of magnesium alloy and titanium metal components in the four samples was 10:1, 8:1, 6:1 and 4:1 respectively. The above four samples were respectively tested by detection methods such as scanning electron microscope observation, mechanical property test, biocompatibility test, degradability test, corrosion resistance test and antibacterial property test, and the preferred component proportion of magnesium alloy and titanium metal was obtained as 8:1.

[0086] Exemplarily, four mixed samples of magnesium alloy and copper metal with different ratios are set. The component ratios of magnesium alloy and copper metal in the four samples are 10:1, 8:1, 6:1, and 4:1 respectively. The above four samples are respectively tested by detection methods such as scanning electron microscope observation, mechanical property test, biocompatibility test, degradation test, corrosion resistance test, and antibacterial property test, and the preferred component ratio of magnesium alloy and copper metal is obtained as 8:1.

[0087] Exemplarily, four mixed samples of magnesium alloy and epoxy resin with different ratios are set. The component ratios of magnesium alloy and epoxy resin in the four samples are 10:1, 8:1, 6:1, and 4:1 respectively. The above four samples are respectively tested by detection methods such as scanning electron microscope observation, mechanical property test, biocompatibility test, degradation test, corrosion resistance test, and antibacterial property test, and the preferred component ratio of magnesium alloy and epoxy resin is obtained as 8:1.

[0088] In some embodiments, a certain proportion of titanium metal, copper metal, and epoxy resin can be mixed to determine the first composite layer. Here, exemplarily, the component ratios of magnesium alloy, titanium metal, copper metal, and epoxy resin in the first composite layer are 9:1:1:1. The first composite layer with this component ratio not only has high strength and hardness, but also has good biocompatibility and degradation performance. At the same time, the corrosion resistance and antibacterial properties of this deposition layer are also significantly improved.

[0089] In some embodiments, in step S13, the aqueous solution of amino group is diammonium hydrogen phosphate solution. Of course, other solutions can also be used as the aqueous solution of amino group as long as the solution contains amino group. The following will be described with diammonium hydrogen phosphate solution.

[0090] In step S13, the process of obtaining the second magnesium alloy composite material includes:

[0091] Method A:

[0092] Polish the first magnesium alloy composite material and prepare a diammonium hydrogen phosphate solution with a preset concentration;

[0093] Immerse the polished first magnesium alloy composite material into the diammonium hydrogen phosphate solution. The solution temperature is 80°C, and the standing time after immersion is 30 - 60 minutes to obtain the second magnesium alloy material.

[0094] In the above Method A, exemplarily, the diammonium hydrogen phosphate solution with a preset concentration can be prepared according to the following steps: Dissolve 0.65 g of diammonium hydrogen phosphate in 100 ml of deionized water, and stir evenly to obtain the diammonium hydrogen phosphate solution.

[0095] In some embodiments, in step S13, the process of obtaining the second magnesium alloy composite material includes:

[0096] Method B:

[0097] Polish the first magnesium alloy composite material, prepare a mixed solution of diammonium hydrogen phosphate and calcium chloride, and adjust the pH value of the mixed solution of diammonium hydrogen phosphate and calcium chloride to 6.3 - 6.5;

[0098] Immerse the polished first magnesium alloy composite material into the mixed solution of diammonium hydrogen phosphate and calcium chloride, the solution temperature is 85°C, and the standing time after immersion is 30 - 60 minutes to obtain the second magnesium alloy material.

[0099] In the above Method B, exemplarily, the preparation of the mixed solution of diammonium hydrogen phosphate and calcium chloride can be carried out according to the following steps: Dissolve 0.05 g of diammonium hydrogen phosphate in 100 ml of deionized water, add 0.05 g of calcium chloride after stirring and dissolving, and adjust the pH value to 6.3 - 6.5 with 1 mol / L nitric acid.

[0100] In some embodiments, in step S13, the process of obtaining the second magnesium alloy composite material includes:

[0101] Method C:

[0102] Polish the first magnesium alloy composite material, prepare a mixed solution of diammonium hydrogen phosphate and calcium chloride, and adjust the pH value of the mixed solution of diammonium hydrogen phosphate and calcium chloride to 6.3 - 6.5;

[0103] Immerse the polished first magnesium alloy composite material into the mixed solution of diammonium hydrogen phosphate and calcium chloride, the solution temperature is 85°C, and the standing time after immersion is 30 - 60 minutes;

[0104] Dissolve polycaprolactone in an organic solvent to obtain a polycaprolactone solution;

[0105] Immerse the first magnesium alloy composite material soaked in the mixed solution of diammonium hydrogen phosphate and calcium chloride into the polycaprolactone solution, and repeat the lifting for the first preset number of times to obtain the second magnesium alloy composite material.

[0106] In the above Method C, exemplarily, the method for preparing the polycaprolactone solution can be carried out according to the following steps: Put 2 g of polycaprolactone (PCL) into 40 ml of ethyl acetate, and dissolve the polycaprolactone under the heating state of ethyl acetate at 55 - 60°C to obtain a polycaprolactone solution. The first preset number of times is 3 times, that is, immerse the first magnesium alloy composite material soaked in the mixed solution of diammonium hydrogen phosphate and calcium chloride into the polycaprolactone solution, slowly lift it 3 times and then dry it in the air to obtain the second magnesium alloy composite material.

[0107] In some embodiments, in step S13, the process of obtaining the second magnesium alloy composite material includes:

[0108] Method D:

[0109] grinding the first magnesium alloy composite material to prepare a mixed solution of diammonium hydrogen phosphate and calcium chloride, and adjusting the pH value of the mixed solution of diammonium hydrogen phosphate and calcium chloride to 6.3-6.5;

[0110] The polished first magnesium alloy composite material is immersed in a mixed solution of diammonium hydrogen phosphate and calcium chloride, the solution temperature is 85° C., and the immersion time is 30-60 minutes;

[0111] dissolving polycaprolactone in an organic solvent to obtain a polycaprolactone solution;

[0112] The first magnesium alloy composite material soaked in a mixed solution of diammonium hydrogen phosphate and calcium chloride is immersed in a polycaprolactone solution, and the pulling is repeated for a second preset number of times to obtain a second magnesium alloy composite material, wherein the second preset number of times is greater than the first preset number of times.

[0113] In the above-mentioned method D, illustratively, the method for preparing the polycaprolactone solution can be carried out according to the following steps: 2 g of polycaprolactone (PCL) is placed in 40 ml of ethyl acetate, and the polycaprolactone is dissolved in the ethyl acetate at 55-60° C. to obtain a polycaprolactone solution. The second preset number of times is 6 times, that is, the first magnesium alloy composite material immersed in the mixed solution of diammonium hydrogen phosphate and calcium chloride is immersed in the polycaprolactone solution, slowly pulled 6 times, and then dried in the air to obtain a second magnesium alloy composite material.

[0114] In some embodiments, in step S14, the second magnesium alloy composite material obtained by the above method A, B, C or D is subjected to surface modification treatment, which can be performed according to the following method:

[0115] e. Chemical modification method: The functional group layer is prepared by introducing functional groups on the surface of the material, usually using chemical reagents such as silane coupling agents for reaction. This method is applicable to a variety of materials, and the type and density of functional groups can be adjusted by changing the type of modifier.

[0116] f. Solution impregnation method: dissolve the compound containing the target functional group in a solvent, then immerse the material in the solution for adsorption, and react at high temperature to form a functional group layer. This method is applicable to a variety of materials, but requires careful control of the solvent, immersion conditions, etc. to achieve a high modification efficiency.

[0117] g. Ion beam assisted technology: Ion beams bombard the surface of the material to form defects and cause local chemical reactions, thereby forming a functional group layer on the surface. This method is suitable for some materials such as high melting point metals and can achieve high-resolution control.

[0118] h. Biological modification method: Utilize specific chemical modification processes in organisms, such as yeast surface display technology, etc., to construct specific functional groups on the material surface. This method is applicable to biocompatible materials and can achieve highly bi-specific modifications.

[0119] Through the above surface modification treatment, functional groups such as carboxyl (-COOH) and hydroxyl (-OH) in the compound will form condensates with functional groups such as amino (-NH2) in the tissue, and further form peptide bonds. The formation of these condensates can enhance the affinity between the magnesium alloy surgical suture and the tissue, promoting healing. Secondly, functional groups such as carbonyl (-C=O) in the compound can undergo reduction reactions with active substances such as free radicals in the tissue, thereby reducing the oxidative stress reaction in the tissue and preventing tissue damage. Here, it should be noted that for different actual application scenarios, the above different surface modification treatment methods can be flexibly used to treat magnesium alloy wires.

[0120] In some embodiments, the following factors are considered in the preparation of magnesium alloy materials:

[0121] 1) The strength of magnesium alloy materials can be enhanced by means of fine grain strengthening, precipitation strengthening, solid solution strengthening, second phase strengthening or deformation strengthening. Here, when using the solid solution strengthening method, alloying elements are added according to the purpose of alloy design to form a solid solution and enhance the strength of the magnesium alloy body, and the conditions that the alloying elements have an impact on the material properties and no harmful effects should be met. There are many factors affecting the magnesium solid solution, such as crystal structure, atomic valence state and electrochemical factors, etc. If the atomic radius difference between the solvent and solute is <15%, a broad solid solution will be formed. Therefore, preferably, the alloying elements are selected as zinc, strontium, zirconium, copper and rare earth elements, etc.

[0122] 2) When analyzing the structure of the magnesium alloy material composition and its microstructure, it can be observed and analyzed by means of scanning electron microscopy, transmission electron microscopy, electron microscopy or metallographic structure, etc. In some embodiments, after obtaining the target magnesium alloy composite material, the following steps are further included:

[0123] Clean the target magnesium alloy material under sterile conditions and conduct a quality assessment on the target magnesium alloy material. The quality assessment includes physical property detection, chemical property detection, biocompatibility detection and microbial contamination impact detection of the target magnesium alloy material.

[0124] Here, since the magnesium alloy sutures used clinically need to have good mechanical properties, meet the requirements of various surgical sutures and can withstand the tension and pressure during surgical sutures. At the same time, the packaging of magnesium alloy medical sutures also needs to comply with the relevant standards of medical devices to ensure their safety and hygiene during transportation and use. Therefore, it is necessary to conduct experiments and safety evaluations on the obtained target magnesium alloy composite materials.

[0125] The specific test methods are as follows:

[0126] 1) Conduct a corrosion resistance experiment test on the target magnesium alloy composite material obtained by Method A (hereinafter referred to as No. 1); use the electrochemical impedance spectroscopy method to measure the electrochemical impedance spectra of the magnesium alloy before and after treatment in 0.9% NaCl aqueous solution to obtain Figure 1 the electrochemical impedance spectra and Table 1 shown below. Table 1 shows the electrochemical impedance data, corrosion resistance efficiency and service life description of ordinary AZ31 magnesium alloy and No. 1 magnesium alloy in 0.9% NaCl solution. Figure 1 From left to right in the figure are: the Nyquist diagrams of ordinary AZ31 magnesium alloy and No. 1 magnesium alloy; the schematic diagram of the change of impedance amplitude modulus of ordinary AZ31 magnesium alloy and No. 1 magnesium alloy with frequency; the schematic diagram of the change of phase of ordinary AZ31 magnesium alloy and No. 1 magnesium alloy with frequency.

[0127] Table 1 Electrochemical impedance data, corrosion resistance efficiency and service life of magnesium alloy in 0.9% NaCl solution before and after surface treatment

[0128] Sample <![CDATA[R s / Ω·cm 2 > <![CDATA[R f / Ω·cm 2 > <![CDATA[R ct / Ω·cm 2 > IE / % <![CDATA[i corr / A·cm -2 > <![CDATA[V d / mm·a -1 > Time / d AZ31 16.57 - 47.82 / 1.18E-3 26.6 1.10 1# 19.39 962.5 272 96.11 6.14E-05 1.38 21.2

[0129] It can be seen from Figure 1 the figure and Table 1 that the untreated AZ31 magnesium wire (radius 0.08 mm) can be uniformly corroded for 1.10 days; for the No. 1 magnesium alloy after surface treatment, the expected service time is 21.2 days. It can be calculated from this that the corrosion rate of the magnesium alloy after being treated by the above method is reduced by about 25 times.

[0130] 2) Conduct a corrosion resistance experiment test on the target magnesium alloy composite material obtained by Method B (hereinafter referred to as No. 2); use the electrochemical impedance spectroscopy method to measure the electrochemical impedance spectra of the magnesium alloy before and after treatment in 0.9% NaCl aqueous solution to obtain Figure 2 the electrochemical impedance spectra and Table 2 shown below. Table 2 shows the electrochemical impedance data, corrosion resistance efficiency and service life description of ordinary AZ31 magnesium alloy and No. 2 magnesium alloy in 0.9% NaCl solution.

[0131] Table 2 Electrochemical impedance data, corrosion resistance efficiency and service life of magnesium alloy in 0.9% NaCl solution before and after surface treatment

[0132] Sample Rs / Ω·cm2 Rf / Ω·cm2 Rct / Ω·cm2 IE / % icorr / A·cm-2 Vd / mm·a-1 Time / d AZ31 16.57 - 47.82 / 1.18E-3 26.6 1.10 2# 33.23 41.03 3376 98.59 1.17E-05 0.263 111

[0133] From Figure 2 Table 2, it can be seen that the untreated AZ31 magnesium wire (radius 0.08 mm) can be uniformly corroded for 1.10 days; for the No. 2 magnesium alloy after surface treatment, the expected service life is 111.0 days. From this calculation, it can be known that the corrosion rate of the magnesium alloy after being treated by the above method is reduced by about 71 times.

[0134] 3) Conduct a corrosion resistance experiment test on the target magnesium alloy composite material obtained by method C (hereinafter referred to as No. 3); use the electrochemical impedance spectroscopy method to measure the electrochemical impedance spectra of the magnesium alloy before and after treatment in a 0.9% NaCl aqueous solution, and obtain Figure 3 the electrochemical impedance spectra and Table 3 as shown. Among them, Table 3 shows the electrochemical impedance data, corrosion resistance efficiency and service life description of the ordinary AZ31 magnesium alloy and No. 3 magnesium alloy in a 0.9% NaCl solution.

[0135] Table 3 Electrochemical impedance data, corrosion resistance efficiency and service life of magnesium alloy before and after surface treatment in 0.9% NaCl solution

[0136] Sample <![CDATA[R s / Ω·cm 2 > <![CDATA[R f / Ω·cm 2 > <![CDATA[R ct / Ω·cm 2 > IE / % <![CDATA[i corr / A·cm -2 > <![CDATA[V d / mm·a -1 > Time / d AZ31 16.57 - 47.82 / 1.18E-3 26.6 1.10 3# 33.23 552.6 9352 99.51 6.39E-06 0.143 204

[0137] From Figure 3 Table 3, it can be seen that the untreated AZ31 magnesium wire (radius 0.08 mm) can be uniformly corroded for 1.10 days; for the No. 3 magnesium alloy after surface treatment, the expected service life is 204.0 days. From this calculation, it can be known that the corrosion rate of the magnesium alloy after being treated by the above method is reduced by about 206 times.

[0138] 4) Conduct a corrosion resistance experiment test on the target magnesium alloy composite material obtained by method D (hereinafter referred to as No. 4); use the electrochemical impedance spectroscopy method to measure the electrochemical impedance spectra of the magnesium alloy before and after treatment in a 0.9% NaCl aqueous solution, and obtain Figure 4 the electrochemical impedance spectra and Table 4 as shown. Among them, Table 4 shows the electrochemical impedance data, corrosion resistance efficiency and service life description of the ordinary AZ31 magnesium alloy and No. 4 magnesium alloy in a 0.9% NaCl solution.

[0139] Table 4 Electrochemical impedance data, corrosion resistance efficiency and service life of magnesium alloy before and after surface treatment in 0.9% NaCl solution

[0140] Sample <![CDATA[R s / Ω·cm 2 > <![CDATA[R f Ohm·cm 2 > <![CDATA[R ct / Ω·cm 2 > IE / % <![CDATA[i corr / A·cm -2 > <![CDATA[V d / mm·a -1 > Time / d AZ31 16.57 - 47.82 / 1.18E-3 26.6 1.10 4# 33.23 6.381E4 4.093E5 99.98 1.74E-07 3.91E-3 747

[0141] From Figure 4As can be seen from Table 4, the untreated AZ31 magnesium wire (radius 0.08 mm) can be uniformly corroded for 1.10 days; for the No. 4 magnesium alloy after surface treatment, the expected service life is 747.0 days. From this calculation, it can be known that the corrosion rate of the magnesium alloy after being treated by the above method has decreased by about 9856 times.

[0142] Furthermore, the polarization curves of AZ31 magnesium alloy in 0.9% NaCl solution before and after surface modification treatment were measured as Figure 5 shown, and the corrosion potential, corrosion current density and service life of each sample were calculated, as shown in Table 5.

[0143] Table 5 Corrosion potential, corrosion current density and service life of magnesium alloy in 0.9% NaCl solution before and after surface treatment

[0144]

[0145] From Figure 5 and Table 5, it can be seen that the corrosion rate of the untreated AZ31 magnesium alloy is about 5.05 mm / a. It is expected that the untreated AZ31 magnesium alloy wire (diameter 0.08 mm) can be uniformly corroded for 5.78 days. For the No. 1, No. 2, No. 3, and No. 4 magnesium alloys after treatment, the expected service lives are 30.2 days, 51.8 days, 181 days, and 744 days respectively.

[0146] Based on the above experimental data, the present application further carried out surgical experiments on different samples. Here, on the premise of keeping other conditions unchanged, surgical suture experiments were carried out on the above four magnesium alloy materials of No. 1, No. 2, No. 3, and No. 4. The schematic diagrams of the wounds after suture are as Figures 7a to 7f shown, where Figure 7a , Figure 7b , Figure 7c and Figure 7d are respectively the schematic diagrams of the changes in the wounds within one week after suture with the magnesium alloy materials of No. 1, No. 2, No. 3, and No. 4; Figure 7e is the schematic diagram of the changes in the wound within one week after suture with the magnesium alloy material without surface modification treatment; Figure 7f is the schematic diagram of the changes in the wound within one week after suture with the existing ordinary medical surgical suture.

[0147] As can be seen from the above diagrams and experimental data, among the target magnesium alloy composite materials obtained by surface modification treatment by means of A, B, C, and D, the target magnesium alloy composite material obtained by surface modification treatment by means of D has the best corrosion resistance effect.

[0148] It should be noted that the method of the embodiment of the present application can be executed by a single device, such as a computer or a server. The method of this embodiment can also be applied to a distributed scenario and completed by multiple devices cooperating with each other. In such a distributed scenario, one of the multiple devices can only execute one or more steps of the method of the embodiment of the present application, and these multiple devices will interact with each other to complete the described method.

[0149] It should be noted that some embodiments of the present application have been described above. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims can be executed in a different order than in the above embodiments and still achieve the desired result. Additionally, the processes depicted in the figures do not necessarily require the particular order or sequential order shown to achieve the desired result. In certain embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0150] Those of ordinary skill in the art should understand that: the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of the present application (including the claims) is limited to these examples; within the concept of the present application, the technical features between the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations in different aspects of the embodiments of the present application as described above, which are not provided in detail for the sake of brevity.

[0151] Although the present application has been described in connection with specific embodiments of the present application, many substitutions, modifications, and variations of these embodiments will be apparent to those of ordinary skill in the art based on the foregoing description. For example, other memory architectures (e.g., dynamic RAM (DRAM)) can be used with the embodiments discussed.

[0152] Embodiments of the present application are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the embodiments of the present application shall be included within the protection scope of the present application.

Claims

1. A preparation method of a medical magnesium alloy material, characterized in that, The following steps are involved: Pre-treating to obtain a magnesium alloy wire having a target tissue texture; Performing chemical deposition treatment on the magnesium alloy wire to form a first composite layer on the surface of the magnesium alloy wire to obtain a first magnesium alloy composite material; Immersing the first magnesium alloy composite material in an aqueous solution containing amino groups, so that the first composite layer combines with the amino groups to form a second composite layer, thereby obtaining a second magnesium alloy composite material; Performing surface modification treatment on the second magnesium alloy composite material so that the second magnesium alloy composite material forms a third composite layer containing target functional groups, thereby obtaining a target magnesium alloy composite material; The target functional group includes at least one of a hydroxyl group, a carboxyl group and a carbonyl group; The first composite layer includes a metal component and a non-metal component, wherein the metal component includes at least one of titanium, tungsten, chromium or molybdenum, and the non-metal component includes at least one of polyester, polypropylene, epoxy resin or polyhydroxyalkanoate.

2. The preparation method of the medical magnesium alloy material according to claim 1, characterized in that, The aqueous solution of amino group is diammonium hydrogen phosphate solution.

3. The preparation method of the medical magnesium alloy material according to claim 2, characterized in that, The method of immersing the first magnesium alloy composite material in an aqueous solution containing amino groups, so that the first composite layer is combined with the amino groups to form a second composite layer, and obtaining a second magnesium alloy composite material comprises: grinding the first magnesium alloy composite material to prepare a diammonium hydrogen phosphate solution of a preset concentration; The polished first magnesium alloy composite material is immersed in a diammonium hydrogen phosphate solution at a solution temperature of 80° C. The solution is allowed to stand for 30-60 minutes to obtain a second magnesium alloy material.

4. The preparation method of the medical magnesium alloy material according to claim 2, characterized in that, The method of immersing the first magnesium alloy composite material in an aqueous solution containing amino groups, so that the first composite layer is combined with the amino groups to form a second composite layer, and obtaining a second magnesium alloy composite material comprises: grinding the first magnesium alloy composite material to prepare a mixed solution of diammonium hydrogen phosphate and calcium chloride, and adjusting the pH value of the mixed solution of diammonium hydrogen phosphate and calcium chloride to 6.3-6.5; The polished first magnesium alloy composite material is immersed in a mixed solution of diammonium hydrogen phosphate and calcium chloride at a solution temperature of 85° C. The mixture is allowed to stand for 30-60 minutes to obtain a second magnesium alloy material.

5. The preparation method of the medical magnesium alloy material according to claim 2, characterized in that, The method of immersing the first magnesium alloy composite material in an aqueous solution containing amino groups, so that the first composite layer is combined with the amino groups to form a second composite layer, and obtaining a second magnesium alloy composite material comprises: grinding the first magnesium alloy composite material to prepare a mixed solution of diammonium hydrogen phosphate and calcium chloride, and adjusting the pH value of the mixed solution of diammonium hydrogen phosphate and calcium chloride to 6.3-6.5; The polished first magnesium alloy composite material is immersed in a mixed solution of diammonium hydrogen phosphate and calcium chloride, the solution temperature is 85° C., and the immersion time is 30-60 minutes; dissolving polycaprolactone in an organic solvent to obtain a polycaprolactone solution; The first magnesium alloy composite material immersed in the mixed solution of diammonium hydrogen phosphate and calcium chloride is immersed in the polycaprolactone solution, and the pulling is repeated for a first preset number of times to obtain a second magnesium alloy composite material.

6. The preparation method of the medical magnesium alloy material according to claim 1, characterized in that, The pretreatment to obtain a magnesium alloy wire having a target tissue texture comprises: Physically extruding and deforming the preheated magnesium alloy substrate to form a magnesium alloy wire; The magnesium alloy wire rod having a preset shape is obtained by rolling or drawing process.

7. The preparation method of the medical magnesium alloy material according to claim 1, characterized in that, The chemical deposition treatment of the magnesium alloy wire comprises: The magnesium alloy wire is cleaned and polished using an alkaline solution; The magnesium alloy wire after repeated cleaning and polishing.

8. The preparation method of the medical magnesium alloy material according to claim 1, characterized in that, It further includes: Cleaning the target magnesium alloy composite material under sterile conditions and conducting quality assessment on the target magnesium alloy composite material. The quality assessment includes physical property detection, chemical property detection, biocompatibility detection and microbial contamination influence degree detection of the target magnesium alloy composite material.

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