5216 results about "Biocompatibility Testing" patented technology

Devices formed of or including biocompatible polyhydroxyalkanoates are provided with controlled degradation rates, preferably less than one year under physiological conditions. Preferred devices include sutures, suture fasteners, meniscus repair devices, rivets, tacks, staples, screws (including interference screws), bone plates and bone plating systems, surgical mesh, repair patches, slings, cardiovascular patches, orthopedic pins (including bone filling augmentation material), adhesion barriers, stents, guided tissue repair/regeneration devices, articular cartilage repair devices, nerve guides, tendon repair devices, atrial septal defect repair devices, pericardial patches, bulking and filling agents, vein valves, bone marrow scaffolds, meniscus regeneration devices, ligament and tendon grafts, ocular cell implants, spinal fusion cages, skin substitutes, dural substitutes, bone graft substitutes, bone dowels, wound dressings, and hemostats. The polyhydroxyalkanoates can contain additives, be formed of mixtures of monomers or include pendant groups or modifications in their backbones, or can be chemically modified, all to alter the degradation rates. The polyhydroxyalkanoate compositions also provide favorable mechanical properties, biocompatibility, and degradation times within desirable time frames under physiological conditions.

A medical device (10) includes a structure (12) adapted for introduction into a patient, the structure (12) being formed of a preferably non-porous base material (14) having a roughened or textured surface (16). The structure (12) is conveniently configured as a vascular stent with a base material (14) of stainless steel, nitinol or another suitable material. The medical device (10) also includes a layer (18) of a bioactive material posited directly upon the roughened or textured surface (16) of the base material (14) of the structure (12). The surface (16) of the base material (14) is roughened or textured by etching or by abrasion with sodium bicarbonate or another suitable grit. A preferred roughened or textured surface (16) is thought to have a mean surface roughness of about 10 μin. (about 250 nm) and a surface roughness range between about 1 μin. and about 100 μin. (about 25 nm and about 2.5 μm). The particularly preferred use of sodium bicarbonate as the abrasive to provide roughness or texture to the surface (16) of the base material (14) of the structure (12) is additionally advantageous in the low toxicity of the sodium bicarbonate to production workers, the ease of product and waste cleanup, and the biocompatibility of any residual sodium bicarbonate.

Systems and methods are described for implants with composite coatings to promote tissue in-growth and/or on-growth. An implant includes: a substrate; a structured surface formed on at least a portion of the substrate; and a biocompatible coating deposited on at least a fraction of the structured surface. The systems and methods provide advantages in that the implant has good biocompatibility while the biocompatible coating has good strength.

A high strength abrasion resistant surgical suture material with improved tie down characteristics and enhanced tissue remodeling and biocompatibility includes protein polymer fibers blended with synthetic fibers. The suture features a multifilament cover formed of strands of ultra high molecular weight long chain polyethylene braided with polyester, nylon or other nonabsorbable materials, along with fibers of a protein polymer, such as collagen. The cover surrounds a core formed of twisted strands of ultrahigh molecular weight polyethylene. The core also can include collagen fibers. The suture, provided in a #2 size, has the strength of #5 Ethibond, is ideally suited for most orthopedic procedures, and can be attached to a suture anchor or a curved needle. The collagen fiber enhances tissue remodeling into the suture strand, thus improving biocompatibility.

An intervertebral implant is shaped in the form of a hollow cylinder and has a cover face, a base face, a hollow cylinder wall with an outer lateral area and an inner lateral area, as well as a hollow cylinder central axis. The implant is formed at least 95 percent by volume of a radiolucent material which has a modulus of elasticity of between 1 and 20 GPa. Postsurgical observation is permitted by means of X-rays, and at the same time the implant has a high degree of biocompatibility.

A wound closure apparatus having a porous pad adapted to be fluidly connected to a vacuum pump. The pad is placed over or within a tissue site, and the vacuum pump may be activated to draw air and exudates from the tissue site. The pad contains multiple pore sizes to prevent granulation tissue from migrating into the pad as reduced pressure treatment is applied. The pad has an outer surface adjacent the wound with pore sizes of a diameter of approximately 100 microns or less to prevent tissue from growing into the pad and is treated for biocompatibility.

There is provided a novel wound dressing material which has biocompatibility and infection controllability as essential properties required for such a material, especially excellent flexibility and water absorption properties, thereby accelerating smooth regeneration of a skin defect without stripping off the regenerating skin while removing the material from the skin. A healing agent is added to the wound dressing material which comprises an amorphous film of a crystallinity below 10% and contains fibroin and sericin as a main component.

The present invention is directed to polymeric materials made of biodegradable, bioabsorbable triblock copolymers and implantable devices (e.g., drug-delivery stents) containing such polymeric materials. The polymeric materials may also contain at least one therapeutic substance. The polymeric materials are formulated so as to improve the mechanical and adhesion properties, degradation, biocompatibility and drug permeability of such materials and, thus, implantable devices formed of such materials.

The invention discloses a method for preparing a medical porous tantalum material. The method comprises the following steps of: mixing a poly ethanol aqueous solution and tantalum powder to obtain slurry, wherein the mass concentration of the poly ethanol aqueous solution is 2 to 8 percent; injecting the slurry into an organic foam by vibrating and pressurizing, wherein the vibrating frequency is 20 to 80 times/min; drying; degreasing; sintering, namely raising temperature to 1,500 to 1,800 DEG C at the speed of 10 to 20 DEG C/min under the vacuum degree of 10<-4> to 10<-3>Pa, preserving heat for 120 to 240 minutes, cooling to 200 to 300 DEG C along with a furnace, raising temperature to 1,500 to 1,800 DEG C at the speed of 10 to 20 DEG C/min again, preserving heat for 180 to 240 minutes, raising temperature to 2,000 to 2,200 DEG C at the speed of 5 to 10 DEG C/min, and preserving heat for 120 to 360 minutes; cooling; and performing thermal treatment, namely raising temperature to 800 to 900 DEG C at the speed of 10 to 20 DEG C/min under the vacuum degree of 10<-4> to 10<-3> Pa, preserving heat for 240 to 480 minutes, cooling to 400 DGE C at the speed of 2 to 5 DGE C/min, preserving heat for 120 to 300 minutes, and cooling to room temperature along with the furnace. The porous tantalum prepared by the method is very suitable to be used for the medical implant material for replacing bearing bone tissues, and biocompatibility and the mechanical property can be guaranteed simultaneously.

The invention discloses nano-silver antibacterial hydrogel and a preparation method thereof, wherein the antibacterial hydrogel does not contain a chemical cross-linking agent, a cross-linking sensitizing agent and a cross-linking initiator; the porosity is above 90%; the cross-linking degree is above 50%; by weight, the nano-silver antibacterial hydrogel comprises 3-20% of natural polymer or a derivative thereof, 0-20% of synthetic polymer and 0..005-0.2% of nano-silver; and the nano-silver antibacterial hydrogel is prepared by blending the natural polymer or the derivative thereof, the synthetic polymer, a compound containing silver ions and water and then adopting a radiation cross-linking method. The nano-silver antibacterial hydrogel disclosed by the utility model has good biocompatibility and uniform nano-silver distribution and slow-release capability and is capable of effectively inhibiting bacteria, such as escherichia coli.

The objective of the present invention is to provide a collagen material that possesses physical properties to an extent that allows suturing while still maintaining the biochemical properties inherently possessed by collagen, and retains its shape for a certain amount of time even after application to the body; its production process; and, a medical material on which it is based, examples of which include a artificial tube for nerve, artificial tube for spinal cord, artificial esophagus, artificial trachea, artificial blood vessel, artificial valve or alternative medical membranes such as artificial endocranium, artificial ligaments, artificial tendons, surgical sutures, surgical prostheses, surgical reinforcement, wound protecting materials, artificial skin and artificial cornea, characterized by filling or having inside a substance having biocompatibility that can be degraded and absorbed in the body into a matrix of a non-woven fabric-like multi-element structure of collagen fibers having ultra-fine fibers of collagen as its basic unit.

The present invention provides a method of fixating a mesh implant to a tissue of a subject comprising attaching said mesh implant to said tissue, covering said mesh implant by an antiadhesive barrier, wherein said antiadhesive barrier is attached to said mesh implant by a biocompatible adhesive.

A vascular stent comprising a drug-eluting outer layer of a porous sputtered columnar metal having each column capped with a biocompatible carbon-containing material is described. This is done by placing the stent over a close-fitting mandrel and rotating the assembly in a sputter flux. The result is a coating that is evenly distributed over the outward-facing side of the stent's wire mesh while preventing the sputtered columnar coating from reaching the inward facing side where a smooth hemocompatible surface is required. The stent is then removed from the mandrel, exposing all surfaces, and finally coated with a layer of carbon such as amorphous carbon or diamond-like carbon. The carbonaceous coating enhances biocompatibility without preventing elutriation of a therapeutic drug provided in the porosity formed between the columnar structures. The result is a stent that is adapted to both the hemodynamic and the immune response requirements of its vascular environment.

The invention provides a method for fabricating an implantable medical device to increase biocompatibility of the device, the method comprising: heat setting a polymer construct, wherein the polymer construct is at a temperature range of from about Tg to about 0.6(Tm−Tg)+Tg such that the set polymer construct comprises a crystalline structure having crystals at a size less than about 2 microns; and fabricating an implantable medical device from the heat set polymer construct.

The present invention relates to compositions and methods of treating a disease, such as diabetes, by implanting encapsulated biological material into a patient in need of treatment. This invention provides for the placement of biocompatible coating materials around biological materials using photopolymerization while maintaining the pre-encapsulation status of the biological materials. Several methods are presented to accomplish coating several different types of biological materials. The coatings can be placed directly onto the surface of the biological materials or onto the surface of other coating materials that hold the biological materials. The components of the polymerization reactions that produce the coatings can include natural and synthetic polymers, macromers, accelerants, cocatalysts, photoinitiators, and radiation. This invention also provides methods of utilizing these encapsulated biological materials to treat different human and animal diseases or disorders by implanting them into several areas in the body including the subcutaneous site. The coating materials can be manipulated to provide different degrees of biocompatibility, protein diffusivity characteristics, strength, and biodegradability to optimize the delivery of biological materials from the encapsulated implant to the host recipient while protecting the encapsulated biological materials from destruction by the host inflammatory and immune protective mechanisms without requiring long-term anti-inflammatory or anti-immune treatment of the host.

A microapparatus (11) implantable in the eye (13) comprises a cuasi-bistable microvalve (21) commanded by an intraocular pressure sensor (23) in situ. The microvalve mechanism includes a diaphragm (27) made of a conjugated polymer (29) that shows high deformation and biocompatibility capabilities and which volume depends from the electric potential applied by its pair of electrodes (31). The sensor and actuator-valve are coupled to a drainage conduit (15), the first to deform by the pressure in the ocular globe and the second in a position of buckling to normally close the drainage conduit. The sensor us a membrane of conductive polymeric material with the same properties and whose ohmic resistance varies with the mechanical deformation produced by the ocular pressure.

The invention belongs to the technical field of the preparation of graphene quantum dots (GQDs), and particularly relates to a method for preparing fluorescent graphene quantum dots with controllable oxidation degree and fluorescence by a solvothermal method. According to the technical scheme, the method comprises the following steps of: 1, preparing graphene oxide; 2, preparing green fluorescent graphene quantum dots by a single-step method starting from the graphene oxide; and 3, preparing the fluorescent graphene quantum dots with the controllable oxidation degree by a column chromatographic separation method. According to the method, the sizes and surface oxidation degree of the graphene quantum dots can be controlled under the synthetic condition, so that the fluorescent properties and surface chemical characteristics of the graphene quantum dots are controlled. The prepared graphene quantum dots are high in chemical stability and biocompatibility, low in biotoxicity, and high in property of applicable upconversion fluorescence, matt and the like and bleaching performance. By the excellent properties, the graphene quantum dots have a wide application range in aspects of biological imaging, photovoltaic devices and sensors, and are novel promising fluorescent nano materials.

A surgical tissue adhesive composition contains at least one 1,1-disubstituted electron-deficient olefin macromer. The adhesive composition of the invention has improved biocompatibility as well as controlled biodegradation characteristics and bioactivity. Adhesive co-monomer compositions contain at least one macromer with a pendant oligomer, polymer, or peptide chain as an acrylic ester of the reactive olefin. The polymers formed therefrom have a grafted brush-like nature. The composition is particularly useful for creating an adhesive bond at the junction of living tissue in surgical applications. The adhesive composition may further comprise co-monomer, co-macromer, cross-linker, or inter-penetrating polymer compounds containing peptide sequences that are bioactive or enzyme responsive. The peptide sequences are selected to promote tissue infiltration and healing in a particular biological tissue. The sequences may contain specific cell-adhesion, cell-signaling, and enzyme-cleavable domains. Furthermore, a degradable filler material may be included in the composition to create a reinforced composite. The filler preferably has a higher degradation rate than the polymer matrix, generating porosity upon degradation. The adhesive may further contain entrapped or incorporated drugs or biologics, including antibiotics or growth factors. The adhesive can be used to bind together the edges of living tissues during surgical procedures. The cured composition provides interfacial bonding and mechanical fixation while promoting tissue infiltration and replacement of the adhesive polymer.

The invention discloses a sodium alginate-acrylamide composite aquagel. The preparation method comprises the following steps: 1) proportionally dissolving sodium alginate and acrylamide in water, and uniformly mixing; 2) sequentially adding a crosslinking agent and an initiator, carrying out vacuum degassing treatment, and adding a catalyst; and 3) transferring the obtained mixed solution into a glass mold, and heating to react, thereby obtaining the sodium alginate-acrylamide composite aquagel. The sodium alginate-acrylamide composite aquagel has favorable multivalent ion adsorption capacity and biocompatibility. By combining the polyacrylamide network with the graft copolymerization action of the sodium alginate and acrylamide, the mechanical properties of the aquagel are effectively enhanced. The aquagel is sensitive under the condition of different pH values, can generate intermolecular interactions with multiple cationic dyes and heavy metal ions, and is applicable to the fields of chemical substance adsorptive separation, sewage treatment and the like.

The subject invention concerns non-degradable three dimensional porous collagen scaffolds and coatings. These scaffolds can be prepared around sensors for implantation into a body. A specific embodiment of the invention concerns implantable glucose sensors. Sensors comprising a collagen scaffold of the invention have improved biocompatibility by minimizing tissue reactions while stimulating angiogenesis. The subject invention also concerns methods for preparing collagen scaffolds of the invention. The subject invention also concerns sensors that have a collagen scaffold of the invention around the exterior of the sensor.

A coated implantable medical device is described, wherein the coating comprises a coating matrix and particles of one or more molecular sieves, preferably zeolite of zeogrid particles, optionally loaded with one or more bioactive agents. The coating matrix itself can function as a second drug-carrying interface. The coating comprising the molecular sieve material has an excellent biocompatibility and allows suitable drug delivery into the body of an animal, preferably a mammal and most preferably a human.

The present invention relates generally to medical devices containing nanoporous surfaces and methods for making same. More specifically, the invention relates to implantable vascular stents or other biomedical devices having at least one nanoporous layer that promotes improved cellular adhesion properties that promote healing and long term biocompatibility. In the case of stents, the nanoporous layer promotes re-endothelialization at sites of stent implantation vasculature, improves overall healing, and reduces inflammation and intimal disease progression. The nanoporous layer may be optionally loaded with one or more therapeutic agent to further improve the function of the implanted stent and further augment clinical efficacy.

The invention discloses a high-strength supramolecular hydrogel and a preparation method and application thereof. The high-strength supramolecular hydrogel is prepared by using acryloyl glycinamide as a monomer and triggering in the presence of an initiator; because of the synergistic effect of hydrogen bonds, the supramolecular hydrogel is high in tensile strength and anti-tear while being compressed, can realize functions of thermoplasticity and self-repair at a high temperature, and is good in biocompatibility.

A dispersion includes a plurality of non-chemically modified carbon nanotubes, a soluble block copolymer providing at least one block of a conjugated polymer and at least one block of a non-conjugated polymer, and at least one solvent. At 25° C. exclusive of any mechanical force and after one hour, at least 90% of the plurality of carbon nanotubes exist in the dispersion as isolated carbon nanotubes. The components of the dispersion can be combined with a polymer miscible with the block copolymer to form a carbon nanotube polymer composite upon removal of the solvent. The dispersion can be cast on a substrate and then dried to form a coating, including forming a superhydrophobic coating on the substrate. The non-conjugated polymer of the block copolymer or another miscible conjugated polymer including a copolymer can include functionalities that non-covalently attach to the carbon nanotube surface, such as for manipulating carbon nanotube properties including for enhanced solubility or enhanced biocompatibility.

Compositions containing strontium fortified calcium nanoparticles and/or microparticles, and methods of making and using thereof are described herein. The strontium fortified calcium compounds contain calcium ions, calcium atoms, strontium ions, strontium atoms, and combinations thereof and one or more anions. Exemplary anions include, but are not limited to, citrate, phosphate, carbonate, and combinations thereof. The particles can be formulated for enteral or parenteral administration by incorporating the particles into a pharmaceutically carrier. The compositions can further contain one or more active agents useful for bone diseases or disorders, such as vitamin D, growth factors, and combinations thereof. The compositions can be used to treat or prevent one or more bone diseases or disorders of the bone, such as osteoporosis. Alternatively, the particles can be coated onto a substrate, such as the surface of an implant. The coatings can be used to improved biocompatibility of the implant, prevent loosening of the implant, reducing leaching of metal ions from metallic implants, and reduce corrosion. The coatings can be applied to the substrate using a variety of techniques well known in the art. In one embodiment, the coating is applied using electrophoretic deposition. The use of nano- and/or microparticles that provide high surface area helps to improve interfacial strength between the coating and the implant, which allows for the use of lower sintering temperatures. Lowering sintering temperatures minimizes or prevents thermal decomposition of the coating material and/or degradation of the implant material.

The invention discloses an anti-microbial healing-promoting hydrogel dressing and a preparation method therefor. The main ingredients of the dressing are water-soluble high-molecular polymers, functional polymers with pseudoplastic, anti-microbial agents and water. The above ingredients are dissolved into a whole after a series of technologies. The solution is poured into a mold, and the hydrogel dressing is obtained after curing and irradiation disinfection. The results of wound healing experiments and in vitro anti-microbial experiments show that the hydrogel dressing can promote wound healing effectively, and has good bacteriostatic activity to multiple bacteria (the sterilizing rate is above 70%). The anti-microbial healing-promoting hydrogel dressing is better than existing hydrogel dressings obviously, and has advantages of substantial anti-microbial curative effects, transparency, high water content, simple preparation method, pure product, nontoxicity, innocuousness, no stimulation, good biocompatibility and the like. The hydrogel dressing is suitable for large-area promotion and application.

We have developed an improved vapor-phase deposition method and apparatus for the application of layers and coatings on various substrates. The method and apparatus are useful in the fabrication of biofunctional devices, Bio-MEMS devices, and in the fabrication of microfluidic devices for biological applications. In one important embodiment, oxide/polyethylene glycol coatings provide increased hydrophilicity and improved biocompatibility for medical devices and implants.

A coating composition and related method for use in applying a bioactive agent to a surface in a manner that will permit the bioactive agent to be released from the coating in vivo. The composition is particularly well suited for coating the surface of implantable medical device, such as a stent or catheter, in order to permit the device to release bioactive agent to the surrounding tissue over time. The composition includes a plurality of compatible polymers having different properties that can permit them to be combined together to provide an optimal combination of such properties as durability, biocompatibility, and release kinetics.

The invention relates to a biocolloid hemostatic prepared by aldehyde-modified sodium alginate and amine-modified gelatine. Sodium alginate and gelatine as raw materials; according to ratio, aldehyde-modified sodium alginate solution with the concentration of 5-25% and the same volume of amine-modified gelatine solution with the concentration of 5-40% are mixed; sodium alginate is modified by aldehyde through sodium periodate oxidation; and then gel is obtained by mixing with gelatine modified by ethanediamine. The adopted gelatine and sodium alginate are safe and stable, have good biocompatibility and can be absorbed and degraded by organism. Gel is rapidly formed through Schiff base reaction of aldehyde-modified sodium alginate and amine-modified gelatine, and the gel has the same gel-forming time as fibrin glue but better adhesion property and adhesion strength, can be acted on any part of body through simple local spraying or injection, and can be used as substitute product of fibrin glue.

A poly(ethylene glycol) derivative is disclosed that is activated with a sulfone moiety for selective attachment to thiol moieties on molecules and surfaces. The activated PEG is water soluble, hydrolytically stable for extended periods, and forms hydrolytically stable linkages with thiol moieties. The linkages generally are not reversible in reducing environments. The PEG derivative is useful for modifying the characteristics of substances including modifying biologically active molecules and surfaces for biocompatibility. Methods for synthesizing the active PEG and for preparing conjugates of the active PEG and other substances, including biologically active substances, are also disclosed.