CN107456601B - Zn-Cu series zinc alloy and preparation method and application thereof - Google Patents

Abstract

The invention discloses a Zn-Cu series zinc alloy and a preparation method and application thereof. The Zn-Cu-based zinc alloy of the present invention includes Zn and Cu; the mass content of the Cu in the Zn-Cu-based zinc alloy is 0-30% by weight, but 0 is not included. Its preparation method includes the following steps: (1) mixing the Zn and the Cu to obtain a mixture; (2) treating the mixture according to the following steps a) or b), and then cooling to obtain the the Zn-Cu series zinc alloy; a) under the protection of CO ₂ and SF ₆ atmosphere, the mixture is smelted or sintered; b) under the protection of a vacuum atmosphere, hydrogen is dissolved in the mixture to carry out the smelting. The Zn-Cu series zinc alloy prepared by the invention has suitable mechanical properties, adjustable corrosion rate, good cell compatibility, blood compatibility, excellent antibacterial performance, and can be used for the preparation of biomedical implantation.

Description

Zn-Cu series zinc alloy and preparation method and application thereof

Technical Field

The invention relates to a Zn-Cu series zinc alloy and a preparation method and application thereof, belonging to the technical field of preparation of medical metal materials.

Background

Biomedical materials, also known as biomaterials, are materials used for the purpose of medical treatment, for diagnosis, treatment, repair or replacement of human tissues and organs or for enhancing their functions. With the development of society and the improvement of living standard, the pursuit of people for higher living quality is continuously improved. In order to develop implants with superior clinical performance, researchers have developed a series of new materials and techniques. In practical clinical applications, some specific clinical problems require that the implanted material only plays a temporary supporting role to achieve tissue healing, such as fracture, vascular blockage, etc. The implant prepared from the degradable biological material can be gradually degraded after the mission of assisting the body to be cured is completed, so that the aim of temporary replacement is fulfilled. The biodegradable concept has been widely used in the medical field, and its categories mainly include polymeric materials, bioceramics, biological derivatives, biological hybrid materials, etc.

The biodegradable metal can be completely degraded in vivo, meanwhile, the released corrosion product has a proper host reaction with an organism, and is gradually degraded and absorbed along with the regeneration of tissues or organs after the organism is assisted to realize the treatment purpose, no residual retention of the implant exists, the implant is taken out without a secondary operation, and the pain and the economic burden of a patient are reduced. Therefore, the main component of the biodegradable metal should be an essential metal element that can be metabolized by the human body while exhibiting a suitable degradation rate and pattern in the human body. In recent years, a great deal of attention has been drawn to biodegradable metals, wherein iron-based and magnesium-based alloys have been widely studied due to excellent mechanical properties and biocompatibility, but the degradation rate of pure iron and pure magnesium in vivo is difficult to meet the requirements of clinical medicine, the degradation rate of pure magnesium is too fast, which results in premature loss of mechanical strength and generation of hydrogen bubbles, and the degradation rate of pure iron is lower than the clinical requirements.

From the perspective of standard electrode potential, pure zinc has higher electrode potential than pure magnesium and lower electrode potential than pure magnesium, and the corrosion rate should be between the two, which may be a more suitable choice for clinical medical application. Meanwhile, zinc is an essential element for normal growth of organisms, is an essential trace element for life next to iron in human bodies, contains 1.4-2.3 g of zinc in adult bodies, and contains 33.3mg of zinc in average for men and 22mg for women according to the mass (mg) of zinc in each kilogram of body weight, wherein 60% of zinc exists in muscles, and 30% of zinc exists in bones. Zinc participates in the synthesis of a plurality of enzymes and plays a role in regulation, more than 200 enzymes containing zinc are found, and simultaneously, the zinc-containing enzymes also participate in the synthesis of amino acid and protein, maintain the normal development of organisms, participate in the metabolism of protein and nucleic acid, regulate the synthesis and the function of cells, participate in the synthesis of a plurality of biological membranes, and have the effects of repairing wounds, healing wounds and the like. The zinc deficiency of pregnant women can cause fetal deformity, the zinc deficiency of adults can cause the reduction of the immune system function of the body, and the zinc deficiency of old people mainly shows the reduction of the functions of appetite, memory and the like.

The content of copper in a normal adult is 100-200 mg, the copper mainly exists in a liver, a brain, a heart and a kidney, and 5mg of copper is required to be absorbed every day for the adult. Copper, which affects the absorption, transport and utilization of iron, is a component of blood and promotes the hematopoietic process, and is also a component of some proteins, amino acids and metalloenzymes. The copper ions can destroy the cell membrane of the bacteria, enable the protein structure of the bacteria to be condensed, and change the functions of some enzymes so as to achieve the antibacterial effect.

Disclosure of Invention

The Zn-Cu zinc alloy prepared by the invention has proper mechanical property, adjustable corrosion rate, good cell compatibility and blood compatibility, excellent antibacterial property and can be used for preparing biomedical implants.

The Zn-Cu series zinc alloy provided by the invention comprises Zn and Cu;

the Zn-Cu zinc alloy contains 0 to 30 wt% of Cu, excluding 0.

In the above-mentioned Zn-Cu based zinc alloy, the Zn-Cu based zinc alloy may further include trace elements;

the trace elements are at least one of magnesium, calcium, strontium, iron, manganese, silicon, lithium, silver, tin and rare earth elements; the rare earth element refers to lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu), yttrium (Y), and scandium (Sc);

the mass percentage of the trace elements is 0-3%, but not 0.

In the above Zn-Cu series zinc alloy, the surface of the Zn-Cu series zinc alloy can be coated with a coating;

the thickness of the coating can be 0.01-5 mm;

the coating can be at least one of a degradable polymer coating, a ceramic coating and a drug coating; specifically, the preparation material of the degradable high polymer coating is at least one of the following 1) and 2): 1) at least one of polycaprolactone, polylactic acid, polyglycolic acid, L-polylactic acid, polycyanoacrylate, polyanhydride, polyphosphazene, polydioxanone, poly-hydroxybutyrate, and polyhydroxyvalerate; 2) a copolymer composed of at least two of polylactic acid, polycaprolactone, polyglycolic acid, L-polylactic acid, polycyanoacrylate and polydioxanone; the molecular weight of the preparation material of the degradable polymer coating is 5000-100000;

the ceramic coating is prepared from at least one of hydroxyapatite, tricalcium phosphate, tetracalcium phosphate, calcium hydrophosphate, anhydrous calcium hydrophosphate, octacalcium phosphate, fluorapatite, magnesium hydroxide and strontium phosphide;

the drug coating is at least one of rapamycin and derivative coating, paclitaxel coating, everolimus coating, sirolimus coating, phosphorylcholine coating, heparin coating, mitomycin coating and antibacterial coating.

The Zn-Cu zinc alloy provided by the invention is specifically any one of the following 1) -3), in percentage by weight:

1) consists of 99.5 percent of Zn and 0.5 percent of Cu;

2) consists of 99% of Zn and 1% of Cu;

3) consists of 98% of Zn and 2% of Cu;

the Zn-Cu series zinc alloy provided by the invention is of a compact structure or a porous structure, has good biocompatibility, blood compatibility and excellent antibacterial performance, and is a reliable biomedical implant material.

The invention also provides a preparation method of the Zn-Cu series zinc alloy, which comprises the following steps: (1) mixing the Zn and the Cu to obtain a mixture;

(2) treating the mixture according to the following steps a) or b), and then cooling to obtain the Zn-Cu series zinc alloy;

a) in CO₂And SF₆Under the protection of atmosphere, smelting or sintering the mixture;

b) and dissolving hydrogen into the mixture under the protection of a vacuum atmosphere to carry out smelting.

In the above preparation method, the step (1) further comprises the step of adding and mixing the trace elements.

In the above preparation method, the step of applying the coating layer after the cooling in the step (2) is further included.

In the invention, the method for coating the biodegradable high polymer coating comprises an extraction method, electropolymerization; the method for preparing the degradable high polymer coating by the leaching method comprises the steps of 1) carrying out acid pickling on the Zn-Cu zinc alloy, then carrying out dip coating on the Zn-Cu zinc alloy in a colloid prepared by dissolving a preparation material of the biodegradable high polymer coating in trichloroethane for 10-30 min, and then carrying out uniform-speed drawing and centrifugal treatment to obtain the Zn-Cu zinc alloy coated with the biodegradable high polymer coating; 2) the electropolymerization method comprises the steps of taking a Zn-Cu alloy as a working electrode, dissolving the biodegradable high polymer monomer in a Tris buffer solution, and obtaining a corresponding high polymer coating on the surface of the zinc alloy by a cyclic voltammetry method, wherein the scanning voltage is-0.5V;

the method for coating the ceramic coating can be any one of plasma spraying, electrophoretic deposition, sol-gel, anodic oxidation or hydrothermal synthesis;

the plasma spraying is carried out by using Ar as main plasma gas, the flow rate is 30-100 scfh, and H as secondary plasma gas₂The flow is 5-20 scfh, the spraying current is 400-800A, the spraying voltage is 40-80V, and the spraying distance is 100-500 mm;

the method for electrodepositing the degradable ceramic coating comprises the steps of taking Zn-Cu zinc alloy as a cathode in electrolyte containing calcium and phosphate, wherein the current density is 2-10 mA/cm²After 10-60 min of treatment, cleaning and drying to obtain the Zn-Cu series zinc alloy;

the sol-gel method is characterized in that the Zn-Cu alloy is immersed in the sol of fluoridated hydroxyapatite for 30min, and annealing treatment is carried out for 1h at 400 ℃ after deposition.

The method combining anodic oxidation and hydrothermal synthesis comprises the steps of oxidizing the Zn-Cu series zinc alloy in an electrolyte containing 0.01-0.5 mol/L β -sodium glycerophosphate and 0.1-2 mol/L calcium acetate for 10-30 min at 200-500V, and then treating the zinc-based composite material or the zinc alloy at 200-400 ℃ for 1-4 h.

The method for coating the drug coating is a physical and chemical method; 1) the physical method coating process mainly adopts a soaking and spraying method; the soaking method is that active medicine and controlled release carrier (or single active medicine) are prepared into solution, the specific concentration can be different due to different solution viscosity and required medicine dosage, then the medical implant is soaked into the solution, and then the medicine coating is prepared through necessary post-treatment processes, such as cross-linking, drying, curing and other steps; the spraying method is that the active drug and the controlled release carrier (or the single active drug) are prepared into solution, then the solution is evenly coated on the surface of the medical implant through a spraying tool or a special spraying device, and the drug coating is prepared after post-treatment steps such as drying, curing and the like; the chemical method mainly applies the electrochemical principle to carry out electroplating; 2) the chemical method is that active medicine and/or controlled release carrier are used to generate electric oxidation reduction reaction on the electrode made by the medical implantation, so that the medical implantation surface forms a stable medicine coating connected by chemical bonds.

In the preparation method, the smelting temperature is 600-850 ℃; the smelting method is characterized in that 99.99% of pure zinc and copper are smelted under vacuum protection, and the smelting temperature can be 800 ℃; injecting high-pressure hydrogen under the hydrogen pressure of 1MPa to saturate molten metal liquid, and pouring the molten metal liquid into a water-cooled copper mold to cool the alloy liquid from top to bottom;

the sintering adopts an element powder mixed sintering method, a pre-alloy powder sintering method or a self-propagating high-temperature synthesis method;

the element powder mixed sintering method comprises the steps of uniformly mixing the raw materials for preparing the Zn-Cu alloy with the porous structure, pressing the mixture into a blank, slowly heating the blank to 100-200 ℃ at a speed of 2-4 ℃/min in a vacuum sintering furnace, then quickly heating the blank to 200-300 ℃ at a speed of 30 ℃/min, sintering, and then cooling to obtain the Zn-Cu alloy with the porous structure;

the pre-alloy powder sintering method comprises the steps of mixing the raw materials for preparing the Zn-Cu alloy with the porous structure, performing high-energy ball milling, then performing compression molding, and performing heat treatment at 250-350 ℃ for 10-20 hours to obtain the Zn-Cu alloy with the porous structure;

the self-propagating high-temperature synthesis method is to prepare porous Zn-Mixing the raw materials of Cu alloy, pressing into blank, and placing under the protection of inert gas at 1 × 10³～1×10⁵Pa, at the temperature of 250-350 ℃, and then igniting the Zn-Cu alloy blank to carry out self-propagating high-temperature synthesis to obtain the Zn-Cu alloy with the porous structure.

In the invention, the Zn-Cu zinc alloy prepared by smelting has the porosity of 20-30 percent and the pore diameter of 150-200 mu m.

In the above production method, the method further comprises a step of machining the Zn — Cu-based zinc alloy;

the mechanical processing is at least one of rolling, forging, rapid solidification and extrusion;

specifically, the rolling comprises hot rolling and finish rolling in sequence, wherein the hot rolling can be carried out at 200-300 ℃, the finish rolling can be carried out at 150-250 ℃, and the thickness of the Zn-Cu series zinc alloy after rolling can be 1-2 mm; the hot rolling can be carried out at 260 ℃, the finish rolling can be carried out at 260 ℃, and the thickness of the zinc alloy after rolling can be 1 mm;

the forging comprises the steps of preserving heat of the Zn-Cu series zinc alloy at the temperature of 150-200 ℃ and forging at the temperature of 200-300 ℃, wherein the heat preservation time is 3-50 hours, and the forging speed is not less than 350 mm/s;

the extrusion temperature can be 150-280 ℃, and specifically can be 260 ℃; the heat preservation time before ingot casting extrusion can be 0.5-24 h, specifically 2h, the extrusion ratio can be 10-70, specifically 36, the extrusion speed is 0.1-10 mm/s, specifically 1 mm/s;

the rapid solidification comprises the following steps: under the protection of inert atmosphere (argon), preparing a fast-setting thin strip by adopting a high-vacuum fast quenching system, crushing the thin strip into powder, and finally carrying out vacuum hot pressing for 1-24 h at the temperature of 150-350 ℃; the high vacuum rapid quenching system is arranged as follows: the feeding amount is 2-8 g, the induction heating power is 3-7 kW, the distance between a nozzle and a roller is 0.80mm, the injection pressure is 0.05-0.2 MPa, the rotating speed of a roller is 500-3000 r/min, and the slit size of the nozzle is 1mm multiplied by 8mm multiplied by 6 mm.

The invention further provides application of the Zn-Cu series zinc alloy in preparation of medical implants and/or medical devices capable of being degraded by body fluid.

In the above application, the medical implant degradable by body fluid is at least one of a vascular stent, an esophageal stent, an intestinal stent, a tracheal stent, a biliary stent and a urethral stent;

the medical appliance is at least one of a bone repair appliance, a dental repair appliance and a suture appliance; specifically, the bone repair device may be at least one of a bone plate, a bone nail, a bone pin, a bone rod, an internal spinal fixation device, a ligature wire, a patellar concentrator, bone wax, a bone repair material, a bone tissue repair scaffold, an intramedullary pin, and a bone sleeve;

the dental restoration device may be at least one of a dental implant material, a root canal file, and a dental filling material;

the suturing-type instrument may be at least one of a staple, a suture, and an anastomosis clip.

The invention has the following advantages:

(1) the Zn-Cu zinc alloy prepared by the invention has excellent mechanical property, good tensile strength and yield strength; meanwhile, the biodegradable composite material can be gradually degraded and metabolized in a human body, and has the characteristics of 'degradation and absorption in vivo' and 'effective mechanical support provision'.

(2) When the Zn-Cu series zinc alloy is used for degradable medical implants, the degradation rate can be controlled by regulating and controlling alloy components, and the clinical requirements under different conditions are met.

(3) The Zn-Cu series zinc alloy is applied to degradable medical implants, has no toxicity to endothelial cells and osteoblasts, has good biocompatibility, good cell compatibility and blood compatibility and excellent antibacterial ability, and can regulate the biological functionality (cell compatibility, blood compatibility and antibacterial ability) of the Zn-Cu series zinc alloy by adding different components so as to achieve the aim of designing the biological functionality.

(4) The main constituent elements of the Zn-Cu series zinc alloy prepared by the invention are Zn and Cu, and the two elements are nutrient elements necessary for human bodies, so that the Zn-Cu series zinc alloy has important effects on promoting osteogenesis and new bone formation and has excellent antibacterial performance.

Drawings

FIG. 1 is a photograph of an ingot of a Zn-Cu alloy prepared in example 1 of the present invention.

FIG. 2 is a photograph of a Zn-Cu alloy bar prepared in example 2 of the present invention.

FIG. 3 shows the metallographic phase of Zn-Cu based zinc alloy prepared in example 2 of the present invention, in which FIG. 3(a) is a metallographic phase of pure zinc, FIG. 3(b) is a metallographic phase of Zn-0.5Li, FIG. 3(c) is a metallographic phase of Zn-1Li, and FIG. 3(d) is a metallographic phase of Zn-2 Li.

FIG. 4 is an X-ray diffraction analysis chart of a Zn-Cu based zinc alloy prepared in example 2 of the present invention.

FIG. 5 is a photograph of a tensile specimen of a Zn-Cu system alloy prepared in accordance with the test standards.

FIG. 6 is a polarization curve of electrochemical corrosion of Zn-Cu based zinc alloy in Hank's simulated body fluid in example 5 of the present invention.

FIG. 7 shows the hemolysis ratio of Zn-Cu based zinc alloy in example 6 of the present invention.

Fig. 8 is a picture of the morphology of platelets adhered to the surface of Zn — Cu-based zinc alloy in example 6 of the present invention, in which fig. 8(a) is a picture of the morphology of platelets adhered to a pure zinc surface, fig. 8(b) is a picture of the morphology of platelets adhered to a Zn-0.5Cu surface, fig. 8(c) is a picture of the morphology of platelets adhered to a Zn-1Cu surface, and fig. 8(d) is a picture of the morphology of platelets adhered to a Zn-2Cu surface.

FIG. 9 shows the number of platelets adhered to the surface of a Zn-Cu based zinc alloy in example 6 of the present invention.

FIG. 10 is a graph showing the relative cell proliferation rate of Zn-Cu system Zn alloy 50% leaching solution of example 7 of the present invention after the cells have been exposed for various periods of time.

Detailed Description

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

Materials, reagents and the like used in the following examples are commercially available unless otherwise specified.

The percentages used in the following examples are by weight unless otherwise specified.

Example 1 preparation of as-cast Zn-Cu alloy

Pure Zn (99.99 wt.%), pure Cu (99.9 wt.%) (from Hulusi Zn Co., Ltd.) were used as raw materials, mixed at different mass ratios (98: 2, 99: 1, 99.5: 0.5 mass ratios of Zn to Cu, respectively) and subjected to CO oxidation₂+SF₆Smelting at 800 ℃ under the protection of atmosphere, preserving heat for 10min after raw materials are fully melted, and rapidly cooling by circulating water to prepare a Zn-Cu alloy ingot (namely the Zn-Cu zinc alloy of the invention, the photo is shown in figure 1), wherein in figure 1, Zn-0.5Cu represents that the mass ratio of Zn to Cu is 99.5: 0.5, Zn-1Cu represents that the mass ratio of Zn to Cu is 99: 1, Zn-2Cu represents that the mass ratio of Zn to Cu is 98: 2.

example 2 preparation of an extruded Zn-Cu alloy

Firstly, according to the steps in the embodiment 1 of the invention, an as-cast Zn-Cu alloy ingot is prepared, a Zn-Cu alloy bar (namely, the Zn-Cu zinc alloy of the invention, the picture is shown in figure 2) is prepared in an extrusion mode, radial extrusion is adopted, the ingot casting is kept warm for 2h, the heat preservation temperature is 260 ℃, the extrusion ratio is 36, and the extrusion speed is 1mm/s, so that the Zn-Cu alloy bar with the diameter of 10mm is prepared.

Example 3 microstructure analysis of Zn-Cu based Zinc alloy:

the Zn-Cu series zinc alloy in the embodiment 2 of the invention is cut by a wire to prepare a phi 10x1mm sample, and the sample is sequentially polished by 400#, 800#, 1200# and 2000# SiC sandpaper series. Ultrasonic cleaning in acetone, anhydrous alcohol and deionized water for 15min, and drying at 25 deg.C. And carrying out X-ray diffraction analysis on the sample, etching the sample for 5-30 s by using 4% nitric acid alcohol, washing by using deionized water, drying by blowing, and observing by using a metallographic microscope.

FIG. 3 is a metallographic phase of a Zn-Cu based zinc alloy prepared in example 2 of the present invention, and it can be seen from FIG. 3 that the grain size gradually becomes smaller as the Cu content increases. No significant secondary phases are observed in the Zn-0.5Cu and Zn-1Cu alloys, and in the Zn-2Cu alloy, the secondary phases are uniformly distributed at grain boundaries.

FIG. 4 is an X-ray diffraction analysis chart of a Zn-Cu zinc alloyAs can be seen from FIG. 4, many new small peaks, such as Cu, appear after Cu is added₄Zn, has an influence on the structure of pure zinc.

Example 4 mechanical property test of Zn-Cu series zinc alloy.

A Zn-Cu alloy prepared according to the method of examples 1-2 of the present invention was subjected to tensile test in accordance with ASTM-E8/E8M-09 to prepare tensile specimens (as shown in FIG. 5), car-shine. Respectively ultrasonically cleaning in acetone, absolute ethyl alcohol and deionized water for 15min, and performing tensile test at room temperature by using a universal material mechanics tester at a tensile speed of 0.05mm/mm & min.

The room temperature mechanical properties of the respective samples of Zn-Cu based zinc alloys are shown in Table 1, and it is understood from Table 1 that the strength and hardness of the material are remarkably increased as the Cu content is increased. Zn-2Cu has the highest strength and hardness, and the tensile strength and hardness are 270.39MPa and 78.67MPa respectively.

TABLE 1 mechanical experiment results of Zn-Cu series zinc alloy

Example 5, corrosion performance test of Zn-Cu series zinc alloy:

the electrochemical test is to prepare phi 10x1mmZn-Cu soaking samples by wire cutting of the Zn-Cu series zinc alloy in the embodiment 2 of the invention, and sequentially polish and polish the samples by 400#, 800#, 1200# and 2000# SiC sandpaper series. Ultrasonic cleaning in acetone, anhydrous alcohol and deionized water for 15min, and drying at 25 deg.C. Body fluids (NaCl 8.0g, CaCl) were simulated in Hank's by an Autolab electrochemical workstation₂0.14g，KCl 0.4g，NaHCO₃0.35g, glucose 1.0g, MgCl₂·6H₂O0.1g，Na₂HPO₄·2H₂O 0.06g，KH₂PO₄0.06g，MgSO₄·7H₂0.06g of O dissolved in 1L of deionized water) was electrochemically tested by a three-electrode system.

FIG. 6 is an electrochemical corrosion polarization curve of Zn-Cu series zinc alloy in Hank's solution, and Table 2 is the electrochemical corrosion rate of Zn-Cu series zinc alloy in Hank's solution, and it can be seen from the table that after adding Cu, the corrosion current density of the material is increased, and the corrosion rate of Zn-Cu series alloy is obviously higher than that of pure zinc, and shows a rising trend along with the increase of Cu content.

TABLE 2 electrochemical corrosion rates of Zn-Cu based Zn alloys

Note: in Table 2, standard deviations are shown in parentheses.

Example 6, Zn — Cu-based zinc alloy blood compatibility test:

the extruded Zn — Cu-based zinc alloy in example 2 of the present invention was cut by wire to prepare phi 10x1mm test pieces, and ground and polished by 400#, 800#, 1200# and 2000# SiC sandpaper series. Ultrasonic cleaning in acetone, anhydrous alcohol and deionized water for 15min, and drying at 25 deg.C. Fresh blood was collected from healthy volunteers and stored in an anticoagulation tube containing 3.8 wt.% sodium citrate as an anticoagulant. Using 0.9% physiological saline solution according to the weight ratio of 4: 5 to prepare a diluted blood sample. Soaking the sample in 10mL of normal saline, preserving the temperature at 37 +/-0.5 ℃ for 30min, adding 0.2mL of diluted blood sample, and preserving the temperature at 37 +/-0.5 ℃ for 60 min. 10mL of physiological saline was used as a negative control group, and 10mL of deionized water was used as a positive control group. Centrifuging at 3000rpm for 5min, collecting supernatant, measuring absorbance OD value with Unic-7200 ultraviolet-visible spectrophotometer 545nm, and setting three groups of parallel samples for statistical analysis.

The hemolysis rate was calculated using the following equation:

the hemolysis rate is (experimental OD value-negative OD value)/(positive OD value-negative OD value) × 100%.

After whole blood collection, a portion was centrifuged at 1000rpm for 10min to prepare platelet rich plasma. Platelet rich plasma was dropped onto the surface of the samples and incubated at 37 + -0.5 deg.C for 60min, with 3 replicates per group. A sample was taken out and dissolved in PBS buffer (pH 7.4, 8.006mmol/L NaCl, 0.201mmol/L KCl, 1.420mmol/L Na)₂HPO₄And 0.240mmol/L KH₂PO₄) Wash 3 times to remove non-adherent platelets. The method for fixing the platelets comprises the following steps: 500 per wellmu.L of glutaraldehyde fixing solution with a concentration of 2.5% was fixed at room temperature for two hours, then the fixing solution was aspirated, washed 3 times with PBS, dehydrated in a gradient with 50%, 60%, 70%, 80%, 90%, 95%, 100% alcohol for 10 minutes each concentration gradient, vacuum-dried, observed for the number and morphology of platelet adhesion using a scanning electron microscope (S-4800, Hitachi, Japan), and 10 regions were randomly selected for each sample for platelet counting and statistical analysis.

From fig. 7, it can be seen that the hemolysis rates of Zn-Cu series zinc alloys are all less than 5% of the clinically required safety threshold, and the hemolysis rates tend to increase with the increase of Cu content, but are still lower than the standard of ASTM non-hemolytic material (2%) in general, and the Zn-Cu series zinc alloys of the present invention show good compatibility of erythrocytes and hemoglobin.

Fig. 8 is a photograph showing the morphology of platelets adhered to the surface of Zn-Cu-based zinc alloy, which mostly grows pseudopodium in shape, like octopus, and illustrates that the platelets are in an activation stage, the Zn-Cu-based zinc alloy of the present invention has a certain stimulation effect on the platelets, and the extent of spreading of the platelets on the surface of the material is higher and higher with the increase of the copper content. FIG. 9 shows the number of platelets adhering to the surface of a Zn-Cu alloy, and it can be seen that the number of platelets adhering to the surface of a Zn-Cu alloy according to the present invention is small compared to pure zinc, and the number of platelets adhering to the surface of a material is the lowest when the Cu content is 1%.

Example 7 cell compatibility test of Zn-Cu based Zinc alloy:

a Zn-Cu series zinc alloy is prepared according to the method of the embodiment 2 of the invention, phi 10x1mm test pieces are prepared by wire cutting, and are ground and polished by 400#, 800#, 1200# and 2000# SiC sand paper series. Ultrasonic cleaning in acetone, anhydrous alcohol and deionized water for 15min, and drying at 25 deg.C. Sterilizing the sample with ultraviolet rays, placing in a sterile well plate, and mixing the sample surface area with DMEM cell culture medium containing 10% serum and 1% double antibody (penicillin plus streptomycin mixed solution) at a volume ratio of 1.25cm²DMEM cell culture medium was added at a rate of/mL and placed at 37 deg.C, 95% relative humidity, 5% CO₂Leaching the obtained Zn-Cu series zinc alloy for 24 hours in an incubatorAnd (4) liquid stock solution is sealed and stored in a refrigerator at 4 ℃ for later use.

Inoculating and culturing the leaching liquor and the cells and observing the result: HUVEC and MC3T3 cells were recovered and passaged, suspended in DMEM cell culture medium, inoculated on 96-well culture plates, and added into DMEM cell culture medium for negative control group. In a human body, the concentration of ions precipitated from an implant is reduced by body fluid circulation, in order to simulate the in vivo environment, diluted leach liquor is adopted for cell compatibility evaluation, the obtained Zn-Cu series zinc alloy leach liquor stock solution and a DMEM cell culture medium are diluted according to the ratio of 1:1 to obtain 10% diluted leach liquor, the diluted leach liquor is added into a corresponding experimental group, and the final cell concentration is 2-5 multiplied by 10⁴and/mL. Placing at 37 ℃ and 5% CO₂Culturing in an incubator, taking out the culture plate after 1, 2 and 4 days, observing the morphology of the living cells under an inverted phase contrast microscope and testing the cell survival rate by a CCK8 kit.

FIG. 10 shows the cell viability of HUVEC cells and MC3T3 cells in 50% Zn-Cu alloy leach solution relative to the negative group, indicating that: when the Cu content is 1 wt.%, the survival rate of endothelial cells of the Zn-Cu series zinc alloy is obviously improved compared with that of pure zinc, and the relative proliferation rate is almost twice of that of the pure zinc group by the fourth day of culture. For osteoblasts, pure zinc has obvious cytotoxicity, the cell survival rate of zinc is obviously improved by adding Cu in the Zn-Cu series zinc alloy, and the improvement effect is most obvious when the Cu content is 1 wt.%.

Claims (9)

1. a Zn-Cu series zinc alloy is characterized in that: it is made up of Zn and Cu; In terms of weight percentage, the mass content of the Cu in the Zn-Cu-based zinc alloy is 0-30%, but 0 is not included. 2. The Zn-Cu-based zinc alloy according to claim 1, wherein the surface of the Zn-Cu-based zinc alloy is also coated with a coating; The thickness of the coating is 0.01-5 mm; The coating is at least one of a degradable polymer coating, a ceramic coating and a drug coating. 3. The Zn-Cu series zinc alloy according to claim 2, wherein the preparation material of the degradable polymer coating is at least one of the following 1) and 2): 1) polycaproic acid ester, polylactic acid, polyglycolic acid, L-polylactic acid, polycyanoacrylate, polyanhydride, polyphosphazene, poly-p-dioxanone, poly-hydroxybutyrate and polyhydroxyvalerate 2) a copolymer composed of at least two of polylactic acid, polycaprolactone, polyglycolic acid, L-polylactic acid, polycyanoacrylate and polydioxanone; The molecular weight of the preparation material of the degradable polymer coating is 5,000-100,000; The preparation materials of the ceramic coating are hydroxyapatite, tricalcium phosphate, tetracalcium oxyphosphate, calcium hydrogen phosphate, anhydrous calcium hydrogen phosphate, octacalcium phosphate, fluorapatite, magnesium hydroxide and strontium phosphide. at least one of; The drug coating is rapamycin and its derivative coating, paclitaxel coating, everolimus coating, sirolimus coating, phosphorylcholine coating, heparin coating, mitomycin coating at least one of a layer and an antimicrobial coating. 4. The preparation method of the Zn-Cu-based zinc alloy according to any one of claims 1-3, comprising the steps of: (1) mixing the Zn and the Cu to obtain a mixture; (2) The mixture is treated according to the following steps a) or b), and then cooled to obtain the Zn-Cu-based zinc alloy; a) smelting or sintering the mixture under the protection of CO ₂ and SF ₆ atmosphere; b) The smelting is carried out by dissolving hydrogen in the mixture under the protection of a vacuum atmosphere. 5 . The preparation method according to claim 4 , wherein in the method, after the cooling in step (2), the step of applying the coating layer is further included. 6 . 6. The preparation method according to claim 4 or 5, characterized in that: the temperature of the smelting is 600-850°C; The sintering adopts the element powder mixing sintering method, the pre-alloy powder sintering method or the self-propagating high temperature synthesis method. 7. The preparation method according to claim 4 or 5, wherein the method further comprises the step of machining the Zn-Cu series zinc alloy; The machining is at least one of rolling, forging, rapid solidification and extrusion. 8. The application of the Zn-Cu-based zinc alloy according to any one of claims 1 to 3 in the preparation of body fluid-degradable medical implants and/or medical devices. 9. The application according to claim 8, wherein the body fluid degradable medical implant is at least one of a blood vessel stent, an esophageal stent, an intestinal stent, a tracheal stent, a biliary stent and a urethral stent; The medical device is at least one of a bone repair device, a dental repair device and a suturing device.

Images