104 results about "Hydroxyapatite crystal" patented technology

The present invention relates to electrochemical deposition process of preparing nanometer ordered hydroxyapatite coating on the surface of medical metal material. Cathode electrochemical deposition onto surface of Ti or Ti alloy is performed with electrodeposition solution containing Ca ion of 1E(-4) to 1E(-3) mol/L and LH2PO4 ion of 0.5E(-4) to 1E(-3) mol/L and in voltage of 1-20 V and current of 0.1-10 mA/sq cm. By means of controlling the electrochemical deposition parameters for forming nanometer hydroxyapatite coating, nanometer hydroxyapatite crystal particles may have different aggregate forms to form different secondary microscopic structures, blossom cluster shaped, upstanding or microspore. The form controllable nanometer hydroxyapatite material is biological material with different topologic structure and homogeneous chemical property, and is expected to have raised biocompatibility and bioactivity in clinical application.

The invention relates to a preparation method of a novel open tubular capillary electrochromatographic column for fixing hydroxyapatite as a stationary phase by adopting a bio-ore physical-chemical method. The hydroxyapatite is used as an inorganic material, and is short of active groups, thereby being difficultly fixed on the wall of a capillary tube for capillary electrochromatographic separation. The preparation method comprises the steps of: introducing a pre-oxidized dopamine solution into a preprocessed capillary tube, forming a polydopamine coating on the inner wall of the capillary tube; and introducing a 1.5-time simulated body fluid into the capillary tube modified by polydopamine, placing the capillary tube in a water bath kettle being 37 DEG C for incubation for two weeks, and growing a hydroxyapatite crystal with a nano structure on the inner wall of the capillary tube. The preparation method provided by the invention is simple in process, easy to operate and low in cost; and the whole preparation process is carried out in a water solution without polluting the environment. A hydroxyapatite open tubular column prepared by adopting the preparation method has a good separation effect on a neutral compound, an alkali compound and an acidic compound.

The invention discloses a humanization active forging bone and a preparation method thereof. The humanization active forging bone has main components of hydroxyapatite crystal, natural animal cancellous bones, particles of which the particle size is between 0.1 and 5 millimeters and having three-dimensional netlike porous structures, and a coating of which the pore-size distribution is between 50 and 600 microns and the surface is compounded with extracellular matrix synthesized and excreted by human cells. The forging bone not only has a similar structure with a human bone and is advantageous for cell ingrowth, formation of new bones, and bone structure reconstruction at a transplantation position, but also can be firmly combined with the coating of which the surface is coated with the extracellular matrix synthesized and excreted by the human cells and cell growth factors, promotes the attached growth of in vivo osteoblasts, and accelerates the formation of the new bones; and simultaneously, the forging bone has the advantages of molding randomly and not causing immunological rejection reactions, and can satisfy treatment needs of clinical bone defect and nonunion.

The invention discloses a silk fibroin base integrated osteochondral two-layer bracket, preparation and application thereof. The preparation of the silk fibroin base integrated osteochondral two-layer bracket is carried out by the following steps of: respectively soaking parts of 1/2-3/4 height of a three-dimensional silk fibroin bracket in a calcium chloride ethanol solution, absolute ethyl alcohol, a dipotassium phosphate aqueous solution and de-ionized water; repeating the above operation for 1-15 times, taking the silk fibroin bracket finally soaked by the de-ionized water to soak in the calcium chloride ethanol solution for 5-30 min and subsequently using the de-ionized water to soak the silk fibroin bracket for 3-10 min and pre-calcify the three-dimensional silk fibroin bracket; then soaking the pre-calcified part of the three-dimensional silk fibroin bracket in a bionic calcium ion buffer solution and culturing for 4-8 days at a constant temperature of 37 DEG C to obtain the silk fibroin base integrated osteochondral two-layer bracket. In the pre-calcification process of the invention, the silk fibroin bracket can obtain a nucleating locus of hydroxyapatite crystals; and evenly dispersed weak crystallization nano hydroxyapatites are formed on the surfaces of the porous channels of the bracket by culturing the bracket in the bionic calcium ion buffer solution.

The invention provides an organic-inorganic composite bone repair bioactive material, which is synthesized by using nanometer hydroxyapatite of which the surface is coated with silicon dioxide as an inorganic component, using a biodegradable water-soluble polymer material as an organic component, and according to the mass ratio of the organic component to the inorganic component being equal to between 10 to 1 and 1 to 9. The composite bone repair bioactive material using the nanometer hydroxyapatite of which the surface layer is coated with the silicon dioxide as the inorganic component has better biological reactivity compared with the composite bone repair material using a single nanometer hydroxyapatite as the inorganic component, and overcomes the problems that the prior composite bone repair material using a silicon-doped modified hydroxyapatite as the inorganic component has low biological activity and poor interface reactivity cased by the defects of serious agglomeration and the like due to the excessively large crystal of the hydroxyapatite, thereby having the characteristic of better biological reactivity.

The present invention discloses a polydopamine-modified halloysite nanotube / polylactic acid composite material and preparation and application thereof. The polydopamine-modified halloysite nanotube / polylactic acid composite material comprises 0.05 to 60% by mass of polydopamine-modified halloysite nanotubes and 40 to 99.95% by mass of polylactic acid. By surface modification of the halloysite nanotubes, dispersion of the halloysite nanotubes in a polylactic acid matrix and interface compatibility of the halloysite nanotubes and the polylactic acid matrix can be solved, and the polylactic acid matrix can be effectively enhanced by the halloysite nanotubes; excellent cell affinity and osteogenic activity can be given to the polydopamine-modified halloysite nanotube / polylactic acid composite material, and more significantly, by the use of biological mineralization of a polydopamine layer on the surface of the halloysite nanotubes for formation of hydroxyapatite crystals, eventually good osteo inductivity can be given to the polydopamine-modified halloysite nanotube / polylactic acid composite material. The polydopamine-modified halloysite nanotube / polylactic acid composite material is simple in preparation method, mild in reaction conditions, low in price, and suitable for industrial production.

The process of preparing spherical nanometer hydroxyapatite crystal in water solution features that spherical nanometer hydroxyapatite crystal is synthesized with water soluble polymer PVP as template and through a biomineralization process. The process includes: spreading Ca(NO3)2íñ4H2O powder in the bottom of container A, preading (NH4)3PO4íñ3H2O powder in the weight ratio to Ca(NO3)2íñ4H2O of 1 to 1.67 in the bottom of container B, setting the container B inside the container B, slowly adding PVP aqua of pH 10.5 and concentration 0.02-2 wt% along in inner walls of the two containers to Ca(NO3)2íñ4H2O concentration of 0.01-0.20 mol/L and (NH4)3PO4íñ3H2O concentration of 0.006-0.12 mol/L and the solution overflow through the edge of the container B, stilling at 25 deg.c for 7 days to obtain precipitate, washing the precipitate, sucking filtering and drying to obtain the spherical nanometer hydroxyapatite crystal product. Altering the PVP concentration can regulate the crystal size in 15-150 nm.

The invention discloses selenium-doped hydroxyapatite and a preparation method thereof. The selenium-doped hydroxyapatite which is obtained by the preparation method has an apatite structure; and a selenium element partially replaces the positions of phosphate radical and/or hydroxyl in the hydroxyapatite crystal in the form of seleninic acid radical. The yield of selenium-doped hydroxyapatite ishigh and the selenium-doped hydroxyapatite has high dispersibility.

The invention provides a preparation method of a superhydrophobic hydroxyapatite film layer on the surface of magnesium alloy. The preparation method comprises the following steps: performing surfacepretreatment, preparing a nano-structured hydroxyapatite layer by a hydrothermal method and performing hydrophobization treatment to the hydroxyapatite layer. The hydrothermal method is designed, andby the hydrothermal method, a rod-shaped hydroxyapatite crystal layer adopting micron-scale length and nano-scale diameter is prepared on the surface of the magnesium alloy, then a stearic acid film is prepared on the surface of the nano-structured hydroxyapatite film layer to form a superhydrophobic film layer with the contact angle of 153 degrees under a static droplet, the film layer can reducethe corrosion current density of the magnesium alloy by 2 orders of magnitude and the impedance modulus of coating is increased from 2029 Omega.cm2 to 117674 Omega.cm2. The preparation method of thenano-structured hydrophobic coating is simple, equipment is simple and easy to control, the cost is low, and the controllability is good; the preparation method is suitable for large-scale production.

The invention discloses a method for regenerating a dental prosthetic material and an acidic amino acid-induced demineralized dental enamel outer enamel prism thereof in situ, and belongs to the technical field of in-situ regeneration of dental enamel outer enamel prisms. The preparation method is as follows: firstly, carrying out surface calcium activation onto a dental enamel surface, i.e., grafting calcium ions; then, forming calcium carbonate stable calcium ions step by step; finally, taking calcium carbonate stable calcium ions as foundation forms to synthesize hydroxyapatite crystals. Amino acid participates in the whole process, concentration of the amino acid added in a two-step process is consistent. The hydroxyapatite crystals deposited on the surface of the demineralized dental enamel are orderly and compact in sequence, and uniform in crystal morphology, so that obvious continued growth tendency of an artificial layer can be seen. The preparation method disclosed by the invention lowers protein extracting cost and harsh restrictions on an application environment, and is wide in prospect. The material prepared by the method disclosed by the invention can be applied to cosmetic dental for filling demineralization gaps, also can be used for repairing early-stage enamel demineralization, and can be used as a combined material for bottom pulp capping pit and fissure sealing, and the like.

A medical metal-based titanium oxide-hydroxyapatite nano-composite coating material and a preparation method thereof are disclosed, the medical metal-based titanium oxide-hydroxyapatite nano-composite coating material of the invention comprises a medical metal substrate, the surface of which is a composite coating composed of mutually evenly-dispersed titanium oxide crystal grains and hydroxyapatite crystal grains, in the composite coating, grain sizes of titanium oxide crystal and hydroxyapatite crystal are 30-50nm and 50-150nm, respectively. The invention further comprises the preparation method of the medical metal-based titanium oxide-hydroxyapatite nano material, namely hybrid sol-gel method. The medical metal-based titanium oxide-hydroxyapatite nano-composite coating of the invention is obviously improved in mechanical strength and thermal expansion performance and has the bonding strength reaching 25-45 MPa with medical metal.

The invention discloses a method for synthesizing hydroxyapatite crystals under the control of an organic molecule template. The method comprises the following steps of: by using Ca(NO3)2.4H2O and (NH4)2HPO4 as raw materials and water and alcohol as solvents, adding ethylenediamine tetraacetic acid disodium and stearic acid serving as additives, adjusting pH in the range from 7 to 11, and carrying out thermostatic reaction for 0.5-2 hours at 40-90 DEG C; afterwards, adding the solution to a stainless steel hydrothermal synthesis kettle with a polytetrafluoroethylene inner container, and reacting for 10 to 24 hours at 120 to 190 DEG C; after completion of reaction, obtaining white precipitates; carrying out suction filtration of white precipitates, and washing to obtain the hexagonally prismatic hydroxyapatite crystals. The products obtained by the method have few agglomerates and high purity, are uniform in particle sizes, regular and controllable in shape and low in production cost and can be applied to the field of biomedical science.

The invention discloses a preparation method of high dispersive nano-hydroxyapatite sol in water solution. The method takes sodium citrate and sodium hexametaphosphate as dispersing agents and adopts the two-step process to obtain the high dispersive sol of nano-hydroxyapatite which has the rod-shaped granules with the diameter of 10 to 20nm and the length of 100 to 300nm. The invention has simple process, low experimental conditions and no need of expensive equipments, at the same time, the invention does not introduce organic surfactant, and the stabilizer used is basically harmless to the environment and the biological bodies, furthermore, the invention adopts the two-step method to add the dispersing agents, so the invention can prepare the high dispersive nano-hydroxyapatite sol in a very wide temperature range; the invention makes use of the high dispersity of hydroxyapatite granules to solve the agglomeration problem of inorganic granules in nano-hydroxyapatite polymer compound biological materials, thereby greatly increasing the mechanical properties and the anisotropism of the mechanical properties of the materials and allowing the orthotropic mechanical properties to be more in line with the characteristics of human bone, so the invention can bring benefits to a plurality of patients with bone defects and is also the application direction of hydroxyapatite crystal on the medical clinical aspect.

A method for electrochemically depositing discrete regions of calcium phosphate onto a medical implant. The method includes providing an implant including at least one area having a metallic surface. At least a portion of the metallic surface is contacted with an electrolyte solution comprising calcium ions and phosphate ions. The metallic surface is used as a cathode, and an electrical potential is applied between the cathode and the electrolyte solution. The electrical potential is applied with a constant current density of from about 10 to about 50 mA/cm² for a period of time of from about 1 to about 20 minutes. A plurality of discrete regions of needle-shaped hydroxyapatite crystals are electrochemically deposited onto the metallic surface.

A new adsorbent of a porous mineral oxide material with apatite crystals, preferably hydroxyapatite crystals, in the pores of the mineral oxide material is disclosed. The adsorbent is useful for protein and nucleic acid separations

The invention belongs to the field of biologic materials, and discloses to a bacteria cellulose composite material, as well as a preparation method and an application thereof. Polypeptide with a phosphate radical is grafted on the fiber surface of bacteria cellulose with a nanometer fiber meshwork. A phosphate radical negative ion area can attract calcium positive ions to subside in the bacteria cellulose composite material under the body fluid environment; a hydroxyapatite crystal is induced to be directly mineralized on the surface of the nanometer fiber; and a nanometer gap structure formed by the nanometer fiber network can be taken as a support frame to facilitate the adhesion, the multiplication and the differentiation of osteocytes , therefore, the bacteria cellulose composite material can be used as defective human bone filling and rehabilitating materials.

The invention relates to a reversed-phase crystal collagen-hydroxyapatite bone repair material and a preparation method thereof. Hydroxyapatite microcrystal is dispersed in collagen swelling solution, whereof the pH value is adjusted to 8-12. The collagen and the hydroxyapatite are precipitated simultaneously through a reversed-phase crystal process and then the material of the invention is obtained through a freezing and drying process. The material prepared by the invention is formed by a reversed-phase crystal method, hydroxyapatite crystal is independently crystallized among the collagen fibers, and crystal nucleus of the hydroxyapatite crystal is the hydroxyapatite, whereof a space structure has the characteristics of a three-dimensional porous structure and aperture is 50-500Mum.

The process of preparing hydroxyapatite crystal whisker in great length/diameter ratio includes mixing calcium source solution and phosphorus source solution in proper concentration under the protection of nitrogen while adding assistant for crystal to grow in certain direction, reflux reaction at proper acidity and temperature conditions for certain time, and transferring the reflux resultant to a pressure kettle for static hydrothermal growth to obtain hydroxyapatite crystal whisker in great length/diameter ratio and high purity. The process has the advantages of mild conditions, short preparation period, controllable length/diameter ratio and high product purity. In addition, the product has high bioactivity.

The invention provides a method for melting deposition molding 3D printing of a personal artificial tooth with an artificial bone material. The method comprises the following six steps: preparing a polyether-ether-ketone suspension, preparing a hydroxyapatite crystal whisker suspension, compounding an artificial bone material, performing three-dimensional molding design on an artificial tooth, performing melting deposition molding 3D printing on the artificial tooth and an artificial tooth planting guide plate, performing surface treatment on a planted part of the artificial tooth, and the like. As polyether-ether-ketone and hydroxyapatite crystal whiskers are adopted to compound an artificial bone material as a raw material for the artificial tooth, the artificial tooth is printed by adopting a melting deposition molding 3D printing manner, and furthermore surface treatment is implemented to expose a hydroxyapatite crystal whisker fiber head on the surface of the planted part of the artificial tooth, significant promotion functions on adhesion, proliferation and differentiation of cells are achieved. By adopting the method, personal artificial teeth can be rapidly made and planted, the cost can be minimized, and the operation is safe. The artificial tooth made with the method is relatively good in biocompatibility and bone junction strength when being compared with common artificial teeth.

The present invention relates to polymer base composite material, and is especially the preparation process of one kind of biological composite hydroxyapatite/polymer material. The composite material is used in repairing and substituting defective bone. The preparation process includes surface grafting modification of high density polyethylene, compounding mineralizing liquid, in-situ mineralizing on the surface of the high density polyethylene with hydroxyapatite and injection forming. The present invention has simple technological process, relaxed requirement in apparatus, high interface binding strength of the prepared composite material, homogeneous distribution and regular orientation of the hydroxyapatite crystal, raised biocompatibility and biological and mechanical performance of the composite material. The composite material has elastic modulus not lower than 18 HPa, tensile strength not lower than 120 MPa and bending strength not lower than 140 MPa.

The invention discloses an Sr and Mg doped amorphous apatite material and crystalline apatite material, belonging to the field of biomedical materials. The different concentrations of Sr and Mg doped amorphous apatite material is rapidly prepared by using Ca(NO3)2, Mg(NO3)2, Sr(NO3)2, (NH4)2HPO4 and ammonia-water as raw materials and then is transformed to the different concentrations of Sr and Mg doped nano calcium-deficient hydroxyapatite or nano tricalcium phosphate material through heat treatment. Compared with traditional hydroxyapatite crystalline materials, the amorphous material has higher solubility. The amorphous apatite material and the crystalline apatite material have the beneficial effects that after Sr and Mg doping, Sr can achieve the effects of promoting new bone formation, reducing reabsorption of bone, adjusting calcium metabolism and reducing the activity of osteoclast, and Mg can achieve the effects of affecting early growth of bone substances and regulating growth and remodelling of the bone substances; therefore the synthesized amorphous apatite and the crystallized product thereof have important roles in the fields of bone repair and bone transplantation.

The invention discloses an oil-soluble/water-soluble organic-inorganic three-phase porous micro-nanometer composite bone repair material and a preparation method thereof. From the bionic angle, for better simulating the components, structure and function of natural bone tissues, chitosan and collagen are selected as water-soluble organic matrixes; an oil-soluble high-molecular material polylactic acid is added for improving the performance; a water-soluble phase can be combined with an oil-soluble phase by crosslinking; an in-situ crystallization process of inorganic calcium and phosphorus mineral in the natural bone tissues under the regulation and control of organic matrix biological large molecules is simulated by a hybridization method; a nanometer hydroxyapatite crystal is synthesized on the matrix; an artificial bone defect repair scaffold similar to natural bone extracellular matrix is molded and prepared by utilizing a freeze-drying phase separation technology. The preparation method of the oil-soluble/water-soluble organic-inorganic three-phase porous micro-nanometer composite bone repair material disclosed by the invention is simple in procedures and mild in condition; the prepared composite scaffold is similar to natural bone matrix in constitution and structure, has a typical micro-nanometer structure (micrometer-grade hole diameter size and nanometer crystal), is excellent in performance and high in figurability and can be processed into required shapes.