CN108277386A - A kind of Zn-Li-Mg systems kirsite and the preparation method and application thereof - Google Patents

Abstract

The invention discloses a Zn-Li-Mg series zinc alloy as well as a preparation method and application thereof. The zinc alloy of the present invention includes Zn, Li and Mg; in terms of weight percentage, the mass percentage of Li in the zinc alloy is 0 to 1%, but 0 is not included; the mass percentage of Mg in the zinc alloy is 0 to 1%. 1%, but not including 0; the balance being zinc. The zinc alloy prepared by the invention has excellent mechanical properties, can provide long-term effective supporting force in vivo, has excellent cell compatibility and blood compatibility, and can be used for the preparation of biomedical implants.

Description

A kind of Zn-Li-Mg system zinc alloy and its preparation method and application

technical field

The invention relates to a Zn-Li-Mg series zinc alloy and its preparation method and application, belonging to the technical field of medical metal material preparation.

Background technique

Medical devices made of biomaterials will interact with organisms after being implanted in them. These functions can be used for auxiliary diagnosis, treatment or to help the repair and replacement of damaged tissues and organs of the organism. Obviously, depending on the purpose of implanting medical devices, the appropriate length of implantation time is also different: some devices are suitable for long-term existence in the body, so as to achieve the purpose of long-term service to promote curative effect; while some devices only need to be temporarily or short-term. Therefore, these devices need to be gradually degraded and absorbed during the repair or regeneration of biological tissues or organs.

According to different purposes, biomaterials implanted into organisms can be roughly divided into two categories: permanent biomaterials and degradable biomaterials. The permanent biomaterials include permanent metal biomaterials, permanent ceramic materials and permanent polymer materials. The so-called permanent metal biomaterials mainly include stainless steel, cobalt-based alloys, titanium and titanium alloys, nickel-titanium shape memory alloys, zirconium-based alloys, tantalum and precious metals such as gold, silver, and platinum. At present, permanent metal biomaterials are the most used type of biomedical materials. This kind of material has good strength and toughness, outstanding corrosion resistance and fatigue resistance, and excellent processing performance, and has been widely used in cardiovascular implant intervention therapy and human hard tissue repair (such as bone, tooth, joint and other repair and Replacement) and other fields.

Degradable metals are a new class of medical metal materials represented by magnesium-based alloys and iron-based alloys that have developed rapidly since the beginning of this century. These materials have broken through the traditional idea of using metal implants as biologically inert materials. Instead, it is a new way to cleverly use the characteristics of implanted metals that are prone to corrosion (degradation) in the human body environment (containing chloride ions), expecting to realize the repair function of metal implants in the body in a controllable manner, and finally in human tissue. After completion of reconstruction/function repair, it is completely degraded into metal ions and other products that are harmless to the human body. However, the two materials of iron-based alloy and magnesium-based alloy have their own shortcomings. The degradable metals that were initially studied were iron-based alloys. The disadvantages were that the degradation rate in the human body was too slow, and the degradation products had certain toxic and side effects on the human body. Therefore, magnesium-based alloys (such as AZ31, WE43, Mg-Ca, etc.) gradually become a research hotspot. Although magnesium-based alloys have attractive application prospects as biomaterials, studies have found that magnesium-based alloys corrode too quickly, and implants will quickly lose their mechanical integrity before tissues and organs are fully healed. In order to meet the actual clinical needs, it is necessary to develop novel biodegradable metals.

In the industrial field, zinc metal and its alloys are commonly used metal materials. In industry, zinc metal and its alloys are often used as sacrificial anode materials in electrochemical corrosion protection because of their active chemical properties and easy corrosion. However, compared with magnesium, zinc metal and its alloys have higher corrosion potential and slower corrosion rate, so they are more in line with actual clinical needs and are expected to become new biomedical degradable implant materials and devices.

In the field of life sciences, zinc also plays an important role. Zinc is the second most abundant element in the human body after iron. The total amount of zinc in the human body accounts for about 0.003% of the body weight, 90% of which exists in the muscles and bones, and 10% exists in the blood. According to different ages, the recommended daily intake (RDA) of zinc is between 2-13mg. The human body mainly absorbs zinc through the small intestine, mainly stores it in the liver and kidney, and combines it with metalloproteins in the cells.

Zinc is a component of more than 300 enzymes that support immune function and promote growth and development. Zinc can regulate the expression of biological genes, such as promoting insulin secretion, and improving the immunity of organisms by promoting phagocytosis and producing immunoglobulins. Zinc can protect cardiomyocytes from acute oxidative stress injury, prevent inflammatory response during myocardial injury, promote wound healing, and promote the survival of myocardial stem cells during myocardial recovery. Atherosclerosis is generally accompanied by endothelial cell damage. Studies have shown that zinc can protect endothelial cells and maintain their integrity. Zinc regulates cell apoptosis and inflammation by regulating the combination of transcription factor NF-kB and DNA. In endothelial cells, zinc reduces the risk of atherosclerosis by inhibiting the activity of NF-kB and reducing the expression of endothelial cell adhesion proteins. In vitro cell experiments have shown that zinc ions can promote the proliferation, adhesion and migration of endothelial cells and smooth muscle cells at low concentrations, but have the opposite effect at high concentrations. Related genes affected by zinc ions are related to cell adhesion, injury, growth, angiogenesis, inflammation, and coagulation. For endothelial cells and smooth muscle cells, this concentration is approximately 100 μM and 80 μM, respectively. In the bone environment, zinc in osteoblasts promotes protein synthesis by activating tRNA synthetase and stimulating gene expression, and also increases the amount of DNA in cells, thereby promoting new bone formation and mineralization of osteoblasts. At the same time, zinc promotes the apoptosis of osteoclasts by regulating the calcium ion signaling pathway. Zinc ultimately increases bone mass by promoting bone formation and inhibiting bone resorption. Compared with other trace elements, zinc has the least toxicity in bone metabolism. Zinc deficiency can cause a series of related problems in the epidermis, intestinal tract, central nervous system, immune system, bone and reproductive system.

Contents of the invention

The purpose of the present invention is to provide a Zn-Li-Mg series zinc alloy and its preparation method and application. The zinc alloy prepared by the present invention has excellent mechanical properties, can provide long-term effective supporting force in the body, and has excellent cell compatibility Compatible with blood, it can be used in the preparation of biomedical implants.

A kind of Zn-Li-Mg system zinc alloy provided by the invention, it comprises Zn, Li and Mg;

In terms of weight percentage, the mass percentage of Li in the zinc alloy is 0-1%, but not including 0; the mass percentage of Mg in the zinc alloy is 0-1%, but not including 0; the balance is zinc.

In the above-mentioned zinc alloy, the zinc alloy also includes trace elements;

In the zinc alloy, the mass percentage of the trace elements is 0-3%, but 0% is not included;

The trace element is at least one of manganese, strontium, calcium, silicon, phosphorus, silver, copper, tin, iron and rare earth elements. The Zn-Li-Mg series zinc alloy provided by the present invention is specifically any one of the following 1)-9), which is the percentage by weight:

1) Composed of 99.8% Zn, 0.1% Li and 0.1% Mg;

2) Composed of 99.5% Zn, 0.1% Li and 0.4% Mg;

3) Composed of 99.1% Zn, 0.1% Li and 0.8% Mg;

4) Composed of 99.5% Zn, 0.4% Li and 0.1% Mg;

5) Composed of 99.2% Zn, 0.4% Li and 0.4% Mg;

6) Composed of 98.8% Zn, 0.4% Li and 0.8% Mg;

7) Composed of 99.1% Zn, 0.8% Li and 0.1% Mg;

8) Composed of 98.8% Zn, 0.8% Li and 0.4% Mg;

9) Composed of 98.4% Zn, 0.8% Li and 0.8% Mg.

The present invention also provides a method for preparing the above-mentioned Zn-Li-Mg zinc alloy, comprising the following steps: (1) weighing and mixing raw materials containing the Zn, the Li and the Mg according to the mass percentage of the zinc alloy, get the mixture;

(2) Under the protection of CO ₂ and SF ₆ atmosphere, the mixture is melted, then poured and cooled to obtain the Zn-Li-Mg zinc alloy.

In the above-mentioned preparation method, step (1) also includes the step of adding said trace elements and mixing;

The method also includes the step of smelting the mixture and then standing still; the purpose of standing still is to allow impurities to settle and improve the purity of the zinc alloy material prepared;

The melting temperature may be 420-600°C, specifically 600°C.

In the above preparation method, the method further includes the step of mechanically processing the Zn-Li-Mg zinc alloy;

The machining is at least one of extrusion, rolling, forging and rapid solidification.

In the above-mentioned preparation method, in the method, the step of homogenizing the Zn-Li-Mg series zinc alloy before the mechanical processing; the temperature of the treatment can be 300-400 degrees Celsius, and the time can be 12 ~48 hours; water quenching, oil quenching or air cooling (that is, cooling in air) after the homogenization treatment;

The extrusion temperature can be 150-280°C, the extrusion ratio can be 10-70, and the extrusion speed can be 0.1-10mm/s; the extrusion temperature can be 260°C or 220°C, and the extrusion The specific ratio can be 36 or 16, the extrusion speed can be specifically 1mm/s, and the diameter can be specifically 10mm; the step of heat preservation is included before the extrusion, specifically, it can be heat preservation for 2 hours, and the heat preservation temperature is 260°C or 220°C;

The rolling includes hot rolling and finish rolling in sequence, the hot rolling is carried out at 200-300°C, the finish rolling is carried out at 150-250°C, and the rolling reduction per pass is 1-20%. The Zn-Li-Mg series zinc alloy is rolled for 1-3 mm; the rolling includes the step of heat preservation, specifically, heat preservation at a temperature of 270° C. for 15 minutes;

The forging includes the step of keeping the Zn-Li-Mg zinc alloy at 150-200°C and then forging at 200-300°C, and the holding time is 3-50 hours , the forging speed is not less than 350mm/s;

The rapid solidification includes the following steps: under the protection of an inert atmosphere, the Zn-Li-Mg series zinc alloy is made into a rapid solidification thin strip by using a high vacuum rapid quenching system, and then the thin strip is broken into powder, and finally Under the condition of 200-350°C, vacuum hot pressing for 1-24h.

In the present invention, the inert atmosphere used in the rapid solidification may specifically be argon;

The settings of the high vacuum rapid quenching system are as follows: feeding amount 2-8g, induction heating power 3-7kW, distance between nozzle and roller 0.80mm, injection pressure 0.05-0.2MPa, roller speed 500-3000r/min And the nozzle slit size is 1film×8mm×6mm.

In the above preparation method, the method further includes the step of processing the zinc alloy into a capillary tube.

In the present invention, the method for processing the zinc alloy into a capillary tube specifically includes the following steps: (1) heating the zinc alloy ingot to 150-280°C, keeping it warm for 0.5-1 hour, and extruding the preheated rod The grinding tool is 200-350°C, and the ingot is extruded with an extrusion ratio of 16-36, and the extrusion speed is 0.1-10mm/s to obtain a rod with a diameter of 10mm; (2) Cut the extruded rod into 10 ~50mm is processed into a tube billet, which is used as an extrusion capillary; (3) Put the tube billet into a split extrusion die for extrusion, the extrusion temperature is 150-280 ° C, the extrusion ratio is 16-64, the extrusion die punch The speed is 20-30mm/s to obtain a capillary with an outer diameter of 2-5mm, a wall thickness of 0.1-0.5mm, and a length of 300-1000mm; (4) The above-mentioned capillary is subjected to stress relief annealing at 100-300°C for 0.5-24 hours treatment to obtain a Zn alloy capillary tube.

The present invention also provides the application of the above-mentioned Zn-Li-Mg zinc alloy in the preparation of biodegradable medical implants.

In the above-mentioned application, the application includes any one of the following 1)-4):

1) The Zn-Li-Mg series zinc alloy is used as a degradable stent, and the stent includes at least one of a vascular stent, an esophageal stent, an intestinal stent, a tracheal stent, a biliary stent, a urethral stent, and a prostate stent;

2) The application of the Zn-Li-Mg zinc alloy as a degradable orthopedic implant, the orthopedic implant includes bone plates, bone nails, bone needles, bone rods, spinal internal fixation equipment, ligature wires, At least one of patella concentrator, bone wax, bone repair material, bone tissue repair bracket, intramedullary nail and bone sleeve;

3) Application of the Zn-Li-Mg series zinc alloy as a degradable suture material, and the suture material includes at least one of absorbable sutures, skin staples and medical zippers.

4) Application of the Zn-Li-Mg zinc alloy as a dental material, the dental material includes at least one of dental implant materials, root canal files and tooth filling materials.

In the present invention, the Zn-Li-Mg series zinc alloy has the following a)-d) properties and can be used to prepare body fluid degradable medical implants:

a) the excellent comprehensive mechanical properties of the Zn-Li-Mg series zinc alloy, including strength, hardness and plasticity;

b) blood compatibility of the Zn-Li-Mg zinc alloy;

c) the cytocompatibility of the Zn-Li-Mg series zinc alloy;

d) Degradability of the Zn-Li-Mg series zinc alloy.

The present invention further provides a body fluid degradable medical implant, which is prepared by using the Zn-Li-Mg zinc alloy.

The present invention has the following advantages:

(1) The Zn-Li-Mg alloy prepared by the present invention has excellent mechanical properties, and at the same time has excellent mechanical properties, which can meet the requirements of different parts in the body. At the same time, it can be absorbed and degraded naturally in the body, and has the characteristics of "controllable corrosion degradation characteristics in vivo" and "providing effective mechanical support".

(2) When the Zn-Li-Mg alloy of the present invention is used for degradable medical implants, it can provide long-term effective medical support and protection for injured parts after being implanted in the body (such as fixing and protecting bone tissue or supporting narrow blood vessels) ), and can be gradually absorbed and degraded by the internal environment while tissue repairing. The quantity and volume of the material gradually decrease, and the degradation products and released ions of the material can be absorbed and metabolized by the body to help the body recover and be gradually excreted from the body. After the body fully recovers, the material is completely absorbed and degraded, and there is no need to take it out again.

(3) The zinc alloy provided by the present invention is composed of Zn, Li, and Mg, all of which are trace elements required in the human body, can be naturally metabolized by the human body when degraded in the body, and have biological safety.

(4) In the zinc alloy provided by the present invention, except for pure zinc, all are trace elements, that is, microalloying, which can simplify the composition of the material while obtaining excellent performance, which is conducive to the safety and effectiveness of subsequent materials. facilitated research.

(5) The Li element in the zinc alloy provided by the present invention can significantly strengthen the matrix, the Mg element can further improve the mechanical strength, and can promote the effect of osteogenesis, and the mechanical properties can be obtained by adjusting the types and components of different elements , alloy materials with different degradation properties and functions are applied to implant devices in different environments in the body.

(6) the zinc alloy provided by the present invention can obtain strength and be 391～681MPa, elongation rate is 1.39%～8.92% rod or plate, has excellent strength, and wherein composition is the zinc alloy front strength of Zn0.8Li0.1Mg is 681MPa, which is the zinc alloy with the highest elongation among the reported degradable zinc alloys, and the degradation rate is around 1.74mm/year. The material is non-toxic to endothelial cells, smooth muscle cells and osteoblasts, can promote endothelial and osteoblast proliferation, has excellent blood compatibility, and the addition of Mg can produce the effect of promoting osteogenesis. Zinc alloy itself has antibacterial effect and can be prepared Some medical devices with special purposes.

Description of drawings

Fig. 1 is a photograph of a Zn-Li-Mg zinc alloy ingot prepared in Example 1 of the present invention.

Fig. 2 is a photo of the Zn-Li-Mg system zinc alloy rod prepared in Example 2 of the present invention.

Fig. 3 is a photo of the Zn-Li-Mg zinc alloy plate prepared in Example 3 of the present invention.

Fig. 4 is a stress-strain curve of the Zn-Li-Mg system zinc alloy prepared in Example 1 of the present invention.

Fig. 5 is the electrochemical corrosion curve of the Zn-Li-Mg system zinc alloy of the present invention in simulated body fluid.

Fig. 6 is the relative survival rate of smooth muscle cells in 100% leaching solution of Zn-Li-Mg zinc alloy of the present invention.

Fig. 7 is the relative survival rate of HUVEC human umbilical vein endothelial cells in the 100% extraction solution of Zn-Li-Mg zinc alloy of the present invention.

Fig. 8 shows the relative survival rate of MC3T3-E1 mouse osteoblasts in the 100% leaching solution of Zn-Li-Mg zinc alloy of the present invention.

Fig. 9 shows the morphology of human platelets adhered to the surface of the Zn-Li-Mg zinc alloy of the present invention.

Detailed ways

The experimental methods used in the following examples are conventional methods unless otherwise specified.

The materials and reagents used in the following examples can be obtained from commercial sources unless otherwise specified.

Embodiment 1, preparation as-cast Zn-Li-Mg system zinc alloy

Using pure zinc (99.99wt.%), pure magnesium (99.9wt.%), and zinc-lithium intermetallic compounds as raw materials, according to the mass ratio in the following table:

Zn Li Mg 99.8% 0.1% 0.1% 99.5% 0.1% 0.4% 99.1% 0.1% 0.8% 99.5% 0.4% 0.1% 99.2% 0.4% 0.4% 98.8% 0.4% 0.8% 99.1% 0.8% 0.1% 98.8% 0.8% 0.4% 98.4% 0.8% 0.8%

Mixing, under the protection of CO ₂ +SF ₆ atmosphere, smelting at 600°C, stirring evenly, standing, pouring, and cooling to obtain cast Zn-Li-Mg zinc alloy (as shown in Figure 1).

Embodiment 2, preparation extruded state Zn-Li-Mg system zinc alloy

First, the as-cast Zn-Li-Mg zinc alloy ingot is prepared according to the steps in Example 1 of the present invention, and then the Zn-Li-Mg zinc alloy rod is prepared by extrusion (as shown in Figure 2) , using radial extrusion, ingot insulation for 2 hours, insulation temperature 260 ℃ or 220 ℃, extrusion temperature 260 ℃ or 220 ℃, extrusion ratio 36 or 16, extrusion speed 1mm/s to prepare a diameter of 10mm Zn-Li-Mg series zinc alloy bar, that is, extruded Zn-Li-Mg series zinc alloy.

Embodiment 3, preparation rolling state Zn-Li-Mg system zinc alloy

Firstly, the as-cast Zn-Li-Mg system zinc alloy ingot is prepared according to the steps in Example 1 of the present invention, and then the Zn-Li-Mg system zinc alloy plate is prepared by rolling (as shown in Figure 3), using One-way rolling, hot rolling and finish rolling in sequence, before rolling, keep warm at the rolling temperature of 270°C for 15 minutes, hot rolling at 250°C, finish rolling at 200°C, and the amount of rolling in each pass is 2 %, that is, a rolled Zn-Li-Mg zinc alloy of 1 to 3 mm can be obtained.

Embodiment 4, Zn-Li-Mg system zinc alloy mechanical property test

The Zn-Li-Mg series zinc alloy prepared in Example 1 of the present invention was used to prepare tensile samples according to the ASTM-E8/E8M-09 tensile test standard, respectively. After ultrasonic cleaning in acetone, absolute ethanol and deionized water for 15 min, the tensile and compressive tests were carried out at room temperature using a universal mechanical testing machine for materials with a tensile speed of 0.05 mm/mm min. The results of the tensile strength test are shown in Table 1.

Table 1 Mechanical properties of Zn-Li-Mg zinc alloys

It can be known from the results in Table 1 that the highest yield strength of the Zn-Li-Mg zinc alloy of the present invention is 470 MPa, the highest tensile strength is 681 MPa, and the highest elongation after fracture is 8.92%. As can be seen from the mechanical property data of zinc alloys with 0.1% or 0.5% Li added in Table 1, the strength of the material can be significantly improved by adding Li element through microalloying, and the alloy strength can be further improved by adding Mg element through further microalloying, The tensile strength of Zn0.8Li0.1Mg reaches 681MPa, and its stress-strain curve is as shown in Figure 4. The present invention is an alloy with the highest strength among the reported degradable zinc alloys, and its excellent mechanical properties can endow the material with more Wide range of applications.

Embodiment 5, Zn-Li-Mg system zinc alloy corrosion performance test

The extruded Zn-Li-Mg zinc alloy in Example 2 of the present invention was prepared by wire cutting The Zn-Li-Mg series zinc alloy specimens were ground and polished by 400#, 800#, 1200# and 2000# SiC sandpaper series in sequence. After ultrasonic cleaning in acetone, absolute ethanol and deionized water for 15 min, dry at 25 °C. Afterwards, the electrochemical test is carried out. The electrochemical test is to pass the above-mentioned treated sample through the Autolab electrochemical workstation, and perform the electrochemical test in Hank's simulated body fluid. (Hank's simulated body fluid NaCl 8.0g, CaCl ₂ 0.14g, KCl 0.4g, NaHCO ₃ 0.35g, glucose 1.0g, MgCl ₂ 6H ₂ O 0.1g, Na ₂ HPO ₄ 2H ₂ O 0.06g, KH ₂ PO ₄ 0.06g, MgSO ₄ 7H ₂ O 0.06g dissolved in 1L deionized water)

Fig. 5 is the anodic polarization curve of the Zn-Li-Mg system zinc alloy of the present invention in Hank's simulated body fluid, and the degradation rate of pure zinc and the Zn-Li-Mg system zinc alloy of the present invention is 1.74mm/year through calculation.

Example 6, Cytocompatibility experiment of Zn-Li-Mg zinc alloy

The Zn-Li-Mg series zinc alloy prepared by the method of Example 2 of the present invention is prepared by wire cutting The sample piece is ground and polished by 400#, 800#, 1200# and 2000# SiC sandpaper series. After ultrasonic cleaning in acetone, absolute ethanol and deionized water for 15 min, dry at 25 °C. Test the contact angle of the sample with deionized water. The sample is sterilized by ultraviolet rays, placed in a sterile orifice plate, and mixed with 10% serum and 1% double antibody (penicillin plus streptomycin mixed solution) according to the surface area of the sample. ) DMEM cell culture medium is added to the DMEM cell culture medium at a volume ratio of 1.25cm ² /mL, and placed in a 37°C, 95% relative humidity, 5% CO ₂ incubator for 24h to obtain a Zn-Li-Mg alloy 100% extraction solution stock solution, seal the extraction solution, and store it in a refrigerator at 4°C for later use.

Dilution of extracts and cell inoculation culture and result observation: HUVEC human umbilical vein endothelial cells, VSMC smooth muscle cells and MC3T3-E1 mouse osteoblasts were recovered and passaged, suspended in DMEM cell culture medium, and inoculated in 96-well culture On the plate, after culturing for 24 hours, the negative control group was added with DMEM cell culture medium, the positive control group was added with 10% DMSO-containing cell culture medium, and the experimental group was added with the Zn-Li-Mg alloy dilution extract obtained above to make the final cell The concentration is 2～5×10 ⁴ /mL. Place them in a 37°C, 5% CO ₂ incubator for culture, take out the culture plates after 1, 2, and 4 days, observe the morphology of living cells under an inverted phase-contrast microscope, and test the cell viability with the CCK8 kit.

Figure 6, Figure 7 and Figure 8 are VSMC cells, HUVEC cells and MC3T3-E1 cells in the 100% Zn-Li-Mg zinc alloy leaching solution of the present invention, the relative survival rate, according to the ISO-10993-5 standard, It can be seen from the figure that during the culture period, the Zn-Li-Mg system zinc alloy leaching solution of the present invention has no toxicity to the three kinds of cells, showing good biocompatibility. Especially for endothelial cells and osteoblasts, it also has a significant effect on promoting proliferation. Meets requirements as a biodegradable scaffold material and orthopedic implants.

Embodiment 7, Zn-Li-Mg system zinc alloy blood compatibility test

The rolled Zn-Li-Mg zinc alloy of Example 2 of the present invention was prepared by wire cutting Zn-Li-Mg series zinc alloy specimens were ground and polished by 400#, 800#, 1200# and 2000# SiC sandpaper series. After ultrasonic cleaning in acetone, absolute ethanol and deionized water for 15 min, dry at 25 °C. Fresh blood was collected from healthy volunteers and stored in an anticoagulant tube containing 3.8wt.% sodium citrate as an anticoagulant. Dilute blood samples with 0.9% normal saline at a ratio of 4:5. Soak the sample in 10mL of normal saline, keep warm at 37±0.5°C for 30min, add 0.2mL diluted blood sample, and keep warm at 37±0.5°C for 60min. 10 mL of normal saline was used as a negative control group, and 10 mL of deionized water was used as a positive control group. After centrifugation at 3000rpm for 5 minutes, the supernatant was taken to measure the absorbance OD value with a Unic-7200 ultraviolet-visible spectrophotometer at 545nm, and three groups of parallel samples were set up for statistical analysis.

Calculate the hemolysis rate with the following formula:

Hemolysis rate=(OD value of experimental group-OD value of negative group)/(OD value of positive group-OD value of negative group)×100%.

Experimental results show that the hemolysis rate of the Zn-Li-Mg zinc alloy of the present invention is about 1%, far below the safety threshold of 5% required for clinical use, and shows good blood compatibility. Platelet adhesion experiments showed (as shown in FIG. 9 ) that the platelets adhered to the surface of the Zn-Li-Mn zinc alloy of the present invention had normal morphology and were only slightly activated.

Claims (10)

1. a kind of Zn-Li-Mg systems kirsite, it is characterised in that：The kirsite includes Zn, Li and Mg；

By weight percentage, the mass percent of Li is 0~1% in the kirsite, but does not include 0；In the kirsite The mass percent of Mg is 0~1%, but does not include 0；Surplus is zinc.

2. kirsite according to claim 1, it is characterised in that：The kirsite further includes trace element；

In the kirsite, the mass percentage of the trace element is 0~3%, but does not include 0；

The trace element is at least one of manganese, strontium, calcium, silicon, phosphorus, silver, copper, tin, iron and rare earth element.

3. the preparation method of Zn-Li-Mg systems kirsite, includes the following steps described in claims 1 or 2：(1) it is closed according to the zinc Mass percent is weighed containing the Zn, the Li and Mg raw materials mixing in gold, obtains mixture；

(2) in CO₂And SF₆Under atmosphere protection, the mixture is subjected to melting, then through pouring into a mould, cooling down to get to the Zn- Li-Mg systems kirsite.

4. preparation method according to claim 3, it is characterised in that：Further include that the trace element is added in step (1) The step of mixing；

The method further includes the steps that being stood after the mixture is carried out melting；

The temperature of the melting is 420~600 DEG C.

5. preparation method according to claim 3 or 4, it is characterised in that：The method further includes to the Zn-Li-Mg It is the step of kirsite is machined；

The mechanical processing is at least one of to squeeze, roll, forging and quickly solidifying.

6. preparation method according to claim 5, it is characterised in that：To institute before the mechanical processing in the method State the step of Zn-Li-Mg systems kirsite carries out Homogenization Treatments；The temperature of the processing is 300~400 degrees Celsius, the time 12 ~48 hours；

The temperature of the extruding is 150~280 DEG C, and extrusion ratio is 10~70, and extrusion speed is 0.1~10mm/s；

The rolling includes carrying out hot rolling and finish rolling, the hot rolling successively to carry out at 200~300 DEG C, the finish rolling 150~ It is carried out at 250 DEG C, every time rolls lower amount 1~20%, and Zn-Li-Mg systems kirsite is rolled 1~3mm；

The forging includes keeping the temperature the Zn-Li-Mg systems kirsite under conditions of 150~200 DEG C, then 200 The time of the step of being forged under conditions of~300 DEG C, the heat preservation is 3~50 hours, and the rate of the forging is not less than 350mm/s；

The quick solidification includes the following steps：Under inert atmosphere protection, using high vacuum fast quenching system by the Zn-Li- Rapid coagulation band is made in Mg systems kirsite, then the strip is broken into it is powdered, finally in 200~350 DEG C of condition Under, vacuum hotpressing 1~for 24 hours.

7. according to the preparation method described in any one of claim 3-6, it is characterised in that：The method further includes by the zinc Alloy is processed into the step of capillary tubes.

8. Zn-Li-Mg systems kirsite described in claims 1 or 2 prepare can be in degraded by body fluid medical implant application.

9. application according to claim 8, it is characterised in that：The application includes following 1) -4) in it is any：

1) application of the Zn-Li-Mg systems kirsite as biodegradable stent, the holder include intravascular stent, esophageal stents, At least one of intestinal stent, trachea bracket, biliary tract rack, urethra rack and prostate bracket；

2) application of the Zn-Li-Mg systems kirsite as degradable orthopaedics implantation material, the orthopaedics implant include bone Plate, nail, spicule, bone stick, internal fixation of spine equipment, ligature, patella fracture fixator, bone wax, bone renovating material, bone tissue reparation branch At least one of frame, intramedullary needle and synthetism set；

3) application of the Zn-Li-Mg systems kirsite as degradable suture material, the suture material include absorbable suture At least one of line, skin closure nail and Medical zipper.

4) application of the Zn-Li-Mg systems kirsite as dental material, the dental material include gear division implantation material, root At least one of pipe file and tooth filler.

10. one kind can degraded by body fluid medical implant, it is characterised in that：The implant is using Zn-Li- described in claims 1 or 2 Mg systems kirsite is prepared.