109 results about "Biodegradable magnesium" patented technology

An orthopedic implant comprising a deformable, expandable implant body configured for treating abnormalities in bones, such as compression fractures of vertebra, necrosis of femurs and the like. An exemplary implant body comprises a small cross-section threaded element that is introduced into a bone region and thereafter is expanded into a larger cross-section, monolithic assembly to provide a bone support. In one embodiment, the implant body is at least partly fabricated of a magnesium alloy that is biodegradable to allow for later tissue ingrowth.

A biodegradable magnesium based metallic material for medical use which is degraded and absorbed in vivo, characterized by comprising a film, which contains magnesium oxide and magnesium hydroxide and is formed on the surface of crystallized magnesium or a magnesium alloy by anodic oxidation. This magnesium based metallic material is capable of exhibiting desired mechanical properties such as strength and ductility at an early stage of implantation without changing the mechanical properties inherent to magnesium or its alloy and also controlling the retention time of the mechanical properties to be short or long in a desired manner.

The present invention provides an implant consisting of a biodegradable magnesium-based alloy or partially applied with the magnesium-based alloy, and a method for manufacturing the same. The implant according to the present invention is biodegradable, in which its biodegradation rate can be easily controlled, and the implant has excellent strength and interfacial strength to an osseous tissue.

The invention discloses a method for preparing a biodegradable magnesium alloy intravascular stent in the technical field of biological materials. The method comprises the following steps of: performing stress relief annealing treatment on a magnesium alloy extrusion bar of phi20mm; processing the annealed bar into a tube blank, and extruding the tube blank; performing stress relief annealing treatment on the extruded capillary tube; cutting the annealed capillary tube to form a stent blank by laser; acid-washing and ultrasonically cleaning the cut stent in an ultrasonic cleaner to remove thecut residues; and performing electrochemical polish, ultrasonic cleaning and passivation on the stent. The extruded magnesium alloy capillary tube has uniform tube wall thickness and smooth surface, the tensile strength of the capillary tube can reach 320 to 370MPa, the yield strength can reach 260 to 300MPa, the elongation can reach 24 to 30 percent, and the corrosion rate of the capillary tube in simulated body fluid is 0.14 to 0.24mm/year. The polished intravascular stent has flat, smooth and bright internal and external surfaces. The preparation method provided by the invention can prepare the biodegradable intravascular stent meeting the clinical requirement.

The invention discloses a precise machining method for a capillary tube for a biodegradable magnesium alloy intravascular stent. The method comprises the following steps of: step 1, performing stress relief annealing and machining on a magnesium alloy extrusion bar to obtain a tube blank; step 2, extruding the tube blank to obtain a seamless extrusion tube blank, and performing stress relief annealing; step 3, performing multi-pass rolling and annealing on the annealed seamless extrusion tube blank to obtain a thin tube blank; and step 4, performing multi-pass drawing and annealing on the thin tube blank to obtain the capillary tube for the biodegradable magnesium alloy intravascular stent. The capillary tube produced by the method disclosed by the invention is accurate in dimension (a wall thickness error is not greater than 5%), can be more than 1 metre long, is high in surface quality, uniform in matrix structure, excellent in mechanical property, low in machining cost and high in machining efficiency, and can be subjected to industrialized batch production.

The present invention provides a composite implant comprising pores of a porous structure filled with a biodegradable magnesium-based alloy. Further, the present invention provides a composite implant which filles pores of the porous structure prepared by a metal, a ceramic or a polymer with a biodegradable magnesium-based alloy. Mechanical properties of the composite implant of the present invention are improved because a magnesium-based alloy filled in its pores increases the strength of a porous structure comprised of a metal, a ceramic or a polymer. Further, it can be expected that the magnesium-based alloy filled in the porous structure is decomposed in a living body, thus increasing bone formation rate. Accordingly bone tissue can be rapidly formed because the composite implant of the present invention has high strength and excellent interfacial force between the composite implant and bone tissue, compared to conventional porous materials.

An implant made in total or in parts of a biodegradable magnesium alloy consisting of Y: 2.0-6.0% by weight, Nd: 1.5-4.5% by weight, Gd: 0-4.0% by weight, Dy: 0-4.0% by weight. Er: 0-4.0% by weight, Zr: 0.1-1.0% by weight, Li:0-0.2% by weight, Al: 0-0.3% by weight, under the condition that a) a total content of Er, Gd and Dy is in the range of 0.5-4.0% by weight and b) a total content of Nd, Er, Gd and Dy is in the range of 2.0-5.5% by weight, the balance being magnesium and incidental impurities up to a total of 0.3% by weight.

The invention concerns a fixing for implantable electrodes and catheters. The object of the present invention is inter alia to provide a fixing which takes better account of the different demands in the course of time of ordinary use of the implantable electrodes or catheters. For that purpose the fixing is distinguished in that it includes at least one first structural element comprising a biodegradable material, namely a biodegradable magnesium alloy.

Biodegradable magnesium alloy implantable medical devices are protected to delay onset of corrosion, and thus biodegradability, or to corrode more uniformly. The protection allows for extended effective use of the devices while maintaining biodegradability. Examples of protective coatings include conversion coatings that at least partially remove exposed second phases from a surface of the magnesium alloy and coatings that provide a barrier between water and the surface of the magnesium alloy.

The invention relates to a method for preparing a strontium-containing hydroxyapatite coating on the surface of a biodegradable magnesium alloy. The method comprises the following steps: polishing a magnesium alloy matrix to remove a surface oxidation layer, and cleaning; preparing a hydrothermal solution from calcium nitrate tetrahydrate, EDTA-2 Na, sodium dihydrogen phosphate dihydrate and strontium nitrate; and placing the well treated magnesium alloy matrix into the hydrothermal solution for hydrothermal reaction to obtain the strontium-containing hydroxyapatite coating, a biomimetic calcium phosphate coating, wrapping the magnesium alloy matrix. Compared with the prior art, as the hydrothermal method is adopted to prepare hydroxyapatite, not only is the degradation rate of the magnesium alloy in a human body effectively slowed down, but also the biocompatibility of the magnesium alloy is further improved. As strontium element is added into the hydroxyapatite coating, and as one of trace elements of the human body, strontium has the functions of promoting bone formation and inhibiting bone breakage, both the biological activity and the biocompatibility are improved.

The invention relates to a biomedical absorbable Mg-Si-Sr-Ca multi-element magnesium alloy material as well as a production method and application thereof. The biomedical absorbable Mg-Si-Sr-Ca multi-element magnesium alloy material is suitable for being used as an implant material used in a human body environment. The biomedical absorbable Mg-Si-Sr-Ca multi-element magnesium alloy material comprises the following components in percentage by weight: 0.1%-20.0% of Si, 0.1%-8.0% of Sr, 0.1%-10.0% of Ca and the balance of Mg. The biomedical absorbable Mg-Si-Sr-Ca multi-element magnesium alloy material is a multi-element magnesium alloy system consisting of total nutrient elements of Mg, Si, Sr and Ca; the form, quantity and distribution of a plurality of second phases such as Mg2Si, Mg2Sr, Mg17Sr2, Mg2Ca, CaMgSi and the like in the magnesium alloy are controlled, so that the multi-element magnesium alloy with the optical comprehensive performances is obtained. The biomedical absorbable Mg-Si-Sr-Ca multi-element magnesium alloy material disclosed by the invention has good biocompatibility and mechanical properties, and is a biodegradable magnesium alloy material with excellent comprehensive performances. Besides, the biomedical absorbable Mg-Si-Sr-Ca multi-element magnesium alloy material has a high application value in the fields such as interventional therapy for cardiovascular diseases, intraosseous implant and the like.

The invention discloses a biodegradable magnesium-lithium alloy material and a preparation method of the biodegradable magnesium-lithium alloy material, wherein the biodegradable magnesium-lithium alloy material is composed of 7-14% of lithium, 0.5-5.0% of aluminum, 0.6-3.8% of zinc, 0.01-0.5% of zirconium, 0.1-0.5% of calcium, 0.3-0.7% of strontium and magnesium for the rest; the sum of the weight percentages of the components is 100%. The tensile strength of the material is 170-275 MPa; the yield strength is 125-255 MPa; the elongation rate is 15-65%; and the density is 1.31-1.60. The material can be used for processing blood vessel stents and joint prosthesis replacement parts.

The invention relates to a method for preparing a biodegradable magnesium alloy surface modification fluoridated hydroxyapatite coating. The method comprises the following steps of: pretreating a magnesium alloy substrate, wherein the adopted transfer solution is prepared from sodium dihydrogen phosphate dehydrate and calcium nitrate tetrahydrate; soaking a substrate sample obtained by pretreatment in the transfer solution for 5-100 hours, thus obtaining a calcium-phosphorus coating; soaking a calcium-phosphorus coating sample in an alkali fluoridated transfer solution for 10-48 hours, so as to obtain a fluoridated calcium-phosphorus coating, wherein the alkali fluoridated transfer solution is prepared from sodium hydroxide and sodium fluoride, the concentration of the sodium hydroxide is 3-4g/L, the concentration of the sodium fluoride is 4-5g/L, and heat treatment is not performed; performing heat treatment on the fluoridated calcium-phosphorus coating at the temperature of 300-350 DEG C for 2-5 hours, thus obtaining the fluoridated hydroxyapatite. According to performance detection, the fluoridated hydroxyapatite (FHA) coating prepared by combining a heat treatment process is shaped like a slender sheet and is divergently arranged from the center to the periphery; the electrochemical test proves that the self-corrosion potential of the substrate is improved through the FHA coating; the immersed corrosion experiment proves that an actual protective effect of the FHA coating on the magnesium alloy substrate is better than that of a fluoridated apatite (FA) coating.

The invention discloses a preparation method of a high-corrosion-resistance biodegradable magnesium alloy and belongs to the technical field of materials. The preparation method comprises the following steps: (1) preparing metallic magnesium, metallic zinc, metallic silver and metallic calcium as raw materials; (2) heating metallic magnesium to 760+/-5 DEG C under the protection of N2 and SF6 mixed gas, melting, then sequentially adding metallic silver, metallic calcium and metallic zinc, stirring and uniformly mixing; (3) cooling to 740+/-5 DEG C, introducing argon, and preserving heat and standing at 740+/-5 DEG C for 10-20 minutes; (4) cooling to 720+/-5 DEG C and casting; (5) heating to 300-320 DEG C and preserving the heat for 2-4 hours under the coverage of graphite powder, increasing the temperature to 350-450 DEG C, preserving heat for 8-12 hours, and cooling by water; (6) preserving the heat at 250-350 DEG C for 25-35 minutes, and then carrying out high-temperature plastic deformation; and (7) deforming at normal temperature and intermediately annealing for a plurality of times, and finally cooling by air to normal temperature. According to the method, by virtue of the single-phase fine-grain treatment, the magnesium alloy has high corrosion resistance and good mechanical property; the magnesium alloy can be used for manufacturing different implantable devices.

The invention relates to a preparation method of a biodegradable magnesium alloy surface-modified hydroxyapatite coating. The method specifically comprises the following steps: cutting the magnesium alloy into samples; polishing the samples by aluminum oxide water-resistant abrasive paper to remove surface oxide layers of the magnesium alloy; sequentially ultrasonic-cleaning with deionized water and absolute ethyl alcohol for 5-30 minutes, and drying at room temperature; preparing a conversion liquid by adopting sodium dihydrogen phosphate dihydrate and calcium nitrate tetrahydrate; controlling the molar ratio of calcium and phosphorus at (1:1)-(2:1), the concentration of Ca<2+> at 0.01-0.2M and the P<5+> concentration at 0.01-0.2M; placing pre-treated matrix sample in the conversion liquid to be soaked for 5-100 hours to obtain a calcium and phosphorus coating; preparing the hydroxyapatite coating through the calcium and phosphorus coating by adopting a thermal treatment process: soaking the samples in calcium and phosphorus liquor for 24-72 hours; taking out and directly placing in a Muffle furnace; carrying out thermal treatment at 250-350 DEG C for 2-5 hours; detecting performance. According to the method provided by the invention, the samples taken out from the calcium and phosphorus liquor are placed in the Muffle furnace for direct thermal treatment, so that the method is simpler and easier to operate and control, and the samples can be converted into the hydroxyapatite coating to achieve a considerable corrosion resistant effect.

The invention relates to a method for preparing a degradable magnesium alloy implant material. In the method, (CH3COO)2Ca is added into a base electrolyte to serve as a calcium source, and a phosphate is also added in the base electrolyte to serve as a phosphorus additive to prepare an electrolyte; a magnesium alloy is placed in the electrolyte to serve as an anode; a microarc oxidation power supply is used for supplying electricity, wherein the power supply frequency range is 400-600Hz, the positive duty ratio is 30-50%, the negative duty ratio is 10-30%, and the ratio of the number of the positive pulses to the number of the negative pulses is 1:1; and the degradable magnesium alloy implant material is obtained through electrified reaction under a constant pressure or constant power mode. The implant prepared by the method in the invention has a surface composed of a loose layer and a compact layer, the loose layer surface is distributed with multiple micropores, and the compact layer is in good metallurgic bonding with a basal body so as to ensure a coating to have high hardness, compactness and cohesion as well as good resistance to wear and corrosion; and at the same time, mice acute toxicity tests prove that the coating has good biocompatibility, and simulated body fluid (SBF) soaking tests prove that the coating has good bioactivity, thus the degradable implant materialhas a wide prospect.

The present invention relates to stents which are produced from a magnesium alloy, which is degradable under physiological conditions, having an inorganic coating comprising magnesium fluoride and anorganic coating. The stents according to the invention can additionally be coated with at least one anti-inflammatory, anti-proliferative, anti-angiogenic, anti-restenotic and/or anti-thrombogenic active substance.

An implant made in total or in parts of a biodegradable magnesium alloy consisting of Y: 2.0-6.0% by weight, Nd: 1.5-4.5% by weight, Gd: 0-4.0% by weight, Dy: 0-4.0% by weight, Er: 0-4.0% by weight, Zr: 0.1-1.0% by weight, Li:0-0.2% by weight, Al: 0-0.3% by weight, under the condition that a) a total content of Er, Gd and Dy is in the range of 0.5-4.0% by weight and b) a total content of Nd, Er, Gd and Dy is in the range of 2.0-5.5% by weight, the balance being magnesium and incidental impurities up to a total of 0.3% by weight.

The invention relates to a preparation method of a biodegradable magnesium alloy/calcium phosphate coating composite material. The preparation method comprises the steps of pre-treating a matrix, preparing a conversion liquid, and preparing a bionic calcium phosphate coating to obtain the biodegradable magnesium alloy/calcium phosphate coating composite material. Compared with the prior art, the preparation method has the advantages that the prepared ZK60 magnesium alloy/calcium phosphate coating composite material can be used for remarkably improving the corrosion resistance of a ZK60 magnesium alloy, greatly reducing the degradation rate of the ZK60 magnesium alloy in a bionic body liquid and promoting the research and application of the ZK60 magnesium alloy in the medical field.

The invention discloses a method for preparing a biodegradable magnesium or magnesium alloy and tricalcium phosphate composite material, which comprises the following steps: (1) preparing a porous tricalcium phosphate blank, which is to prepare a porous tricalcium phosphate blank by using an organic foam impregnation method; and (2) permeating magnesium or a magnesium alloy, which is to permeate magnesium or a magnesium alloy into the porous tricalcium phosphate blank by using a fusant permeation method to preparing the magnesium or magnesium alloy and tricalcium phosphate composite material.The method has the advantages that: the prepared composite material has high degree of communication as well as well-guaranteed osteoinductive performance and biodegradability and can be used as material for hard tissue replacement and bone repair, completely degrade after being transplanted into a body for a certain time period and induce the formation of new bones; the production process is simple and does not need special equipment and production cost is low; and the method is suitable to prepare biodegradable composite materials with different properties.

The present invention relates to implants made of a biodegradable magnesium alloy. The inventive implant is made in total or in parts of a biodegradable magnesium alloy comprising:

• • Y: 0-10.0% by weight
  • Nd: 0-4.5% by weight
  • Gd: 0-9.0% by weight
  • Dy: 0-8.0% by weight
  • Ho: 0-19.0% by weight
  • Er: 0-23.0% by weight
  • Lu: 0-25.0% by weight
  • Tm: 0-21.0% by weight
  • Tb: 0-21.0% by weight
  • Zr: 0.1-1.5% by weight
  • Ca: 0-2.0% by weight
  • Zn: 0-1.5% by weight
  • In: 0-12.0% by weight
  • Sc: 0-15.0% by weight
  • incidental impurities up to a total of 0.3% by weight
  • the balance being magnesium and under the condition that
  • a) a total content of Ho, Er, Lu, Tb and Tm is more than 5.5% by weight;
  • b) a total content of Y, Nd and Gd is more than 2% by weight; and
  • c) a total content of all alloy compounds except magnesium is more than 8.5% by weight.