1276 results about "PLGA" patented technology

Non-woven fibrous scaffolds made by electrospinning from the synthetic biodegradable polymer such as, for example, poly(lactic-co-glycolic acid) (PLGA) and natural proteins, such as, for example, gelatin (denatured collagen) and elastin and a method of making thereof.

A stent may be formed from a PLLA tubular polymer construct that is deformed in a blow mold. A desirable polymer morphology resulting in improved stent performance is obtained with a selected radial axial expansion ratio from about 20% to about 70%, a selected radial expansion ratio from about 400% to about 500%, a selected axial rate of deformation propagation at or about 0.3 mm / minute, a selected expansion pressure at or about 130 psi, and a selected expansion temperature that does not exceed 200 deg F. The tubular polymer construct may also be made of PLGA, PLLA-co-PDLA, PLLD / PDLA stereocomplex, and PLLA-based polyester block copolymer containing a rigid segment of PLLA or PLGA and a soft segment of PCL or PTMC.

The invention provides methods, apparatus and kits for regenerating dental tissue in vivo that are useful for treating a variety of dental conditions, exemplified by treatment of caries. The invention uses tissue scaffold wafers, preferably made of PGA, PLLA, PDLLA or PLGA dimensioned to fit into a hole of corresponding sized drilled into the tooth of subject to expose dental pulp in vivo. In certain embodiments the tissue scaffold wafer further comprises calcium phosphate and fluoride. The tissue scaffold wafer may be secured into the hole with a hydrogel, a cement or other suitable material. Either the wafer or the hydrogel or both contain a morphogenic agent, such as a member encoded by the TGF-β supergene family, that promotes regeneration and differentiation of healthy dental tissue in vivo, which in turn leads to remineralization of dentin and enamel. The tissue scaffold may further include an antibiotic or anti-inflammatory agent.

A composition for delivering a tumor therapeutic agent to a patient includes a fast-release formulation of a tumor apoptosis inducing agent, a slow-release formulation of a tumor therapeutic agent, and a pharmaceutically acceptable carrier. An apoptosis-inducing agent in a pharmaceutically acceptable carrier may be administered before or concomitantly therewith. Nanoparticles or microparticles (e.g., cross-linked gelatin) of the therapeutic agent (e.g., paclitaxel) also may be used. The nanoparticles or microparticles may be coated with a bioadhesive coating. Microspheres that agglomerate to block the entrance of the lymphatic ducts of the bladder to retard clearance of the microparticles through the lymphatic system also may be employed. This invention also uses drug-loaded gelatin and poly(lactide-co-glycolide) (PLGA) nanoparticles and microparticles to target drug delivery to tumors in the peritoneal cavity, bladder tissues, and kidneys.

The present invention is directed to a novel poly(diol citrates)-based nanocomposite materials created using completely biodegradable and biocompatible polymers that may be used in tissue engineering. More specifically, the specification describes methods and compositions for making and using nanocomposites comprised of citric acid copolymers and polymers including but not limited to poly(L-lactic acid) (PLLA) and poly(lactic-co-glycolic acid) (PLGA).

The invention is directed to modified polymers with increased drug-loading including compounds of formula (I): wherein Z is a poly(lactic-co-glycolic acid) (PLGA) polymer having molecular weight from 1-15 kDa and where the ratio of lactide to glycolide in the PLGA polymer is from 1:10 to 10:1; formula (II) R1 are independently H, R2, OH, O-alkyl, —O—R2, NH—R2, -linker-R2, or -and R2 are independently one or more therapeutic agents. The invention is also directed to nanoparticle drug delivery systems including a PLGA-b-PEG block copolymer; and a stabilizer and to drug delivery systems including PLGA-b-PEG block copolymer polyvinyl alcohol (PVA) nanoparticle; and the modified polymer substantially as described herein.

The present disclosed subject matter relates to methods and compositions for restoring a diseased or damaged tooth such that infection is inhibited or eliminated and pulp regeneration is facilitated. The disclosed subject matter also includes a composition comprising a physiologically acceptable matrix seeded with pulp cells. The matrix can be capable of being injected into the pulp chamber of a tooth. In some embodiments, the matrix of a composition includes a hydrogel (e.g., collagen, chitosan, alginate, MATRIGEL™, gelatin, JELL-O®, fibrin), a mesh (e.g., polylactide-coglycolide (PLGA) mesh, polylactide (PLA) mesh, or polyglycolide (PGA) mesh, a cross-linked fiber mesh, a nanofiber mesh, a mesh fabric, biodegradable polymer mesh), a microsphere (biodegradable polymer microsphere, a hydrogel microsphere), or a combination of any of the foregoing. In yet other embodiments, the matrix includes a nanofiber, an artificial three-dimensional scaffold material, or a synthetic three-dimensional scaffold material.

The present invention provides methodologies and parameters for fabrication of the hybrid biomaterial by blending pure laminin or complex extracts of tissues containing laminin with biopolymers such as polycaprolactone (PCL), polylactic / polyglycolic acid copolymer (PLGA) or Polydioxanone (PDO) in fluoroalcohols (HFP, TFA), fabrication of substrates and scaffolds and devices from the hybrid biomaterial in forms such as films, nanofibers by electrospinning or microspheres, and the biological or biomedical use of the material or devices derived from it.

Polymeric fibers were microbraided around a mandrel to make a tubular guide tube for nerve regeneration. The polymer used for the fibers was one of poly(L-lactide-co-glycolide) (10:90 PLGA) and chitosan. These polymers are biodegradable and biocompatible. The tubes were studied for their surface morphology and swelling behavior. Biological performance of the tubes was examined in the rat sciatic nerve model with a 12 mm gap. One month after implantation nine out of ten rats showed successful nerve regeneration. Morphometric analysis of regenerated nerves confirmed the quality of the regeneration compatible with those offered by other types of biodegradable nerve guide tubes. The tubes were flexible, permeable and showed no swelling.

Systems and methods for delivering drugs. Crystalline polymeric systems, referred to as CYC carriers, are associated with the drugs, through chemical bonding or through physical association. The crystallinity of the CYC carriers results from the presence of crystallizable side chains, for example long chain n-alkyl moieties, which results in relatively low and sharp melting temperatures. One class of CYC carriers, referred to as CYSC polymers, have a majority of the crystallizable side chains pendant from the polymer backbone. Another class of CYC carriers, referred to as ECC polymers, have a majority of the crystallizable side chains attached to terminal units of the polymer backbone. The ECC polymers can for example be obtained by modification of PLGA polymers. The CYC carriers in another class are non-polymeric. Some CYC carriers, referred to as CYC assemblies, have enhanced crystallinity as a result of the physical association of crystallizable moieties which are present in different types of molecule, for example between a polymer containing crystallizable moieties and a monomer containing crystallizable moieties. Preferably the CYC carrier is bioerodable.

Novel enhanced products and processes for trapping emboli utilize self-expanding skeletons and biodegradable polymer systems, for example stent-like Nitinol® elements and PLGA, to address longstanding issues related to thrombus capture without deleterious impacts on the vasculature or other negative artifacts of the procedure by at least partial post-use dissolution in situ. Drug coating and elution technologies are included as would be known to those skilled in the art.

The triple composite microsphere preparation consists of mainly model medicine, calcium alginate, chitosan, and diglycolide-lactide copolymer. The preparation process includes W / O emulsification, washing with isopropanol to prepare small calcium alginate microcapsule, coating with chitosan to form compact double-layered alginic acid-chitonsan microcapsule, the subsequent emulsifying and solvent volatilization step to coat the double-layered alginic acid-chitonsan microcapsule into diglycolide-lactide copolymer to form the three-layered composite microsphere. The present invention can protect protein and polypeptide medicine in hydrophilic sodium alginate-chitonsan microcapsule environment to reduce abrupt release and incomplete release, prolong the medicine release time, and regulate the medicine releasing mode via altering PLGA composition.

The invention discloses a nerve duct and a preparation method as well as use thereof. The nerve duct is composed of 'shell-core' structured nanofiber, a core layer of the 'shell-core' structured nanofiber contains a biological active component, and a shell layer of the 'shell-core' structured nanofiber contains a biodegradable material; the inside diameter of the nerve duct is 0.5-5.0mm, and the outside diameter thereof is 1.0-6.0mm; the biological active component is a neurotrophic factor; and the biodegradable material is selected from one or more than one of the following components: polylactic-co-glycolic acid (PLGA), poly(lactic acid-caprolactone copolymer) (P (LLA-CL)) and poly(3-hydroxybutyrate) (PHB) or polyphosphoester (PPE).

The invention relates to a kind of laminated gradient composite scaffold material based on the bionic structure and its preparation method. The said material has three or more layers of porous structure, comprising of hyaluronic acid, PLGA, PLA, collagen II and nano-hydroxyapatite (nano-HA) , beta- tricalcium phosphate ( beta-TCP). The upper layer is made by collagen II / hyaluronic acid or PLGA and PLA imitating the cartilage layer. With the counterfeit the calcified cartilage layer in the middle, it is one layer or multi- sublayer, made by nano-HA or beta-TCP with collagen II / hyaluronic acid or PLGA and PLA; the bottom is made of nano-HA or beta-TCP with collagen II or PLGA and PLA. From top to bottom, the content of inorganic material increases in its layers, about 0 to 60 mass percent of layers. The aperture of the scaffold material is 50 to 450 micron, with 70 to 93 percent porosity. The scaffold material made by this invention has an adjustable degradation rate, good mechanical and biocompatible properties, can adapt to culture with cartilage bone cells and compound with growth factor and small molecular or peptides, it can be used to repair cartilage simultaneously.

The invention relates to injection amphiphilic-microsphere-containing hyaluronic acid mixed gel and a preparation method thereof. The microsphere material relates to amphiphilic materials of PLLA-PEG, PLGA, PLGA-PEG and the like. The molecular weight of PLLA or PLGA is 10,000-500,000, the molecular weight of PEG is 1,000-10,000, and in PLGA, LA / GA=90 / 10-10 / 90. The average grain diameter of the microsphere is 1-200 [mu[m, and the mass percent of the microsphere in the gel is 1-50%; the gel is made from hyaluronic acid, divinyl sulphone crosslinked hyaluronic acid, or glycidyl ether crosslinked hyaluronic acid, the molecular weight of the hyaluronic acid is 100,000-3,000,000, and the mass percent of the hyaluronic acid is 1-50%. The gel can be also made from animal-derived collagen, chitosan, amino acid cellulose and sodium alginate. The microsphere mixed gel is prepared in a sodium chloride solution or a phosphate buffered solution with the osmotic pressure of 250-350 mOsm / L and pH of 6.5-7.5. According to the invention, the amphiphilic microsphere is directly mixed with hyaluronic acid gel, can be uniformly distributed in the gel easily, and is unlikely to aggregate into blocks in the water environment of a human body after being injected.

The present invention relates to a nano-calcium phosphates / collagen composite that mimics the natural bone, both in composition and microstructure, as well as porous bone substitute and tissue engineering scaffolds made by a complex of said composite and poly(lactic acid)(PLA) or poly(lactic acid-co-glycolic acid)(PLGA). The invention also relates to the use of said scaffold in treating bone defect and bone fracture.

The invention relates to a PLA / PLGA shell-core microsphere prepared by solid-in-oil-in-water in the technical field of pharmacy and a preparation method thereof. The microsphere comprises 0.01 to 50 percent of medicine, 20 to 99.99 percent of polylactic acid and / or polylactic acid-glycolic acid, or / and 0 to 30 percent of pharmaceutical excipient (weight percentage). The method comprises the steps of: adding medicine particles into a PLA and / or PLGA organic solution to be emulsified, then selecting a hydrophilic organic solvent to re-emulsify to form unhardened balls, finally hardening in another large oil phase, removing the organic solvent and collecting micropheres. The method overcomes the disadvantages of low envelope rate of the prior W / O and W / O / W, serious burst release of S / O / O, and environmental pollution, controls the grain diameter of the microsphere according to the need, does not pollute the environment, and can be applied to the preparation of slow release or controlled release microspheres of various medicines and adjuvants of vaccines.

A bioabsorbable release-sustaining pharmaceutical formulation using a biodegradable release-sustaining base material which can prevent an effective component drug from being released too rapidly just after administration of the formulation and then allow continued release of the drug for at least one month at a defined rate, is provided. For the biodegradable release-sustaining base material, a lactic acid-glycolic acid copolymer (PLGA) with an adjusted distribution in molecular weight is used.

The invention relates to a biodegradable nerve conduit with a bilayer structure and a preparation method thereof. The biodegradable nerve conduit comprises a reticular monofilament liner which is made of polyglycollide-lactide (PLGA) and used as a framework structure and a nano fiber felt which is made of a biodegradable material and used as an outer layer structure. The preparation method comprises the following steps of: (1) preparing PLGA monofilaments by adopting a fused spinning method, stretching for orientating, and then weaving into a reticular liner conduit; (2) dissolving the biodegradable material into an organic solvent to prepare a spinning stock solution with a mass fraction of 3-20 percent; and (3) carrying out electrostatic spinning by using the spinning stock solution on the surface of the reticular liner conduit by taking the reticular liner conduit as a receiving device to obtain the biodegradable nerve conduit. The biodegradable nerve conduit has good biocompatibility, proper degradation time and higher mechanical strength and can promote the regeneration and the restoration of damaged nerves. The preparation method has the advantages of simpleness of operation, low cost, environmental protection, high economic benefit and good application prospect.

The invention provides a long-acting microsphere injection as an antidiabetic medicament, the long-acting microsphere injection comprises liraglutide, PLGA (poly(lactic-co-glycolic acid)), excipients and a surfactant, and the invention simultaneously relates to a preparation method of the injection. Liraglutide long-acting sustained-release microspheres provided by the invention are designed to perform subcutaneous injection once every 28 days, thereby greatly reducing treatment burden on a patient, improving medication compliance and reducing treatment cost; simultaneously, results of in vitro release studies, animal experiments and the like prove that the obtained sustained-release microspheres can slowly release a medicament for a long time in vitro and in vivo.

The invention relates to a nanoparticle and a preparation method thereof. Poly(lactide-glycolide acid) (PLGA) is in the center to serve as a core, phospholipid surrounds the surface of the PLGA core in monolayer and distearoyl phosphatidylethanolamine-polyethyleneglycol-carboxyl (DSPE-PEG-COOH) penetrates the monolayer phospholipid to serve as the shell. The phospholipid, the DSPE-PEG-COOH and the PLGA have good biocompatibility, can entrap hydrophobic drugs and control the drugs to release slowly in the human bodies. The phospholipid surrounds the surface of the PLGA, thus ensuring that the particle can avoid immune system recognition so that the circulating half life of the particle is lengthened. The PEG shell ensures the particle to have spatial stability, static stability, long circulation and other characteristics and to be not easily agglomerated. Meanwhile, carboxyl is easily crosslinked with such ligands as antibodies, peptide, probes and the like, thus ensuring the particle to have targeting characteristic. The preparation method of the nanoparticle is simple, convenient practical and is easy to operate and popularize.

The present invention provides a safe hyaluronic acid base material that is suitable for use in practical hyaluronic acid pharmaceutical preparations capable of distribution at room temperature and having such a low viscosity that injection is easy. The hyaluronic acid pharmaceutical preparations can reside in a joint cavity for a prolonged period of time while exhibiting analgesic effects. More specfically, there is provide a hyaluronic acid modification product in which hyaluronic acid and / or a pharmaceutically acceptable salt thereof is bounded to a block polymer selected from PEO-PPO-PEO, PPO-PEO-PPO, PEO-PLGA-PEO, PLGA-PEO-PLGA, PEO-PLA-PEO and PLA-PEO-PLA. The hyaluronic acid modification product, despite capability of distribution at room temperature and ease in handling because of the low viscosity, can have its viscoelasticity rapidly increased after injection into a living body, so that it is highly useful in treatment of joint diseases, aid in surgical operation, repair of tissue, etc. as a main ingredient of novel and practical hyaluronic acid pharmaceutical preparations.

The invention relates to a preparation method of laponite (LAP)-doped polylactic acid-glycolic acid (PLGA) nanofiber. The method comprises the following steps of: (1) dissolving PLGA into a THF (Tetrahydrofuran) / DMF (Dimethyl Formamide) mixed solvent, and stirring for fully dissolving the PLGA to obtain a PLGA electrostatic spinning solution; (2) uniformly dispersing the LAP into the PLGA electrostatic spinning solution while stirring to obtain a PLGA / LAP electrostatic spinning solution; and (3) performing electrostatic spinning by using the PLGA / LAP electrostatic spinning solution to obtain a PLGA / LAP composite nanofiber felt and drying. The process of the method is simple, a product is easy to prepare, and the PLGA and LAP used have low costs; and the prepared LAP-doped polylactic acid-glycolic acid nanofiber has high mechanical property, high thermal stability, high blood compatibility and high biocompatibility, and has a wide application prospect in the fields of medicament carriers, tissue engineering bracket materials and the like.

The invention provides methods, apparatus and kits for regenerating dental tissue in vivo that are useful for treating a variety of dental conditions, exemplified by treatment of caries. The invention uses tissue scaffold wafers, preferably made of PGA, PLLA, PDLLA or PLGA dimensioned to fit into a hole of corresponding sized drilled into the tooth of subject to expose dental pulp in vivo. In certain embodiments the tissue scaffold wafer further comprises calcium phosphate and fluoride. The tissue scaffold wafer may be secured into the hole with a hydrogel, a cement or other suitable material. Either the wafer or the hydrogel or both contain a morphogenic agent, such as a member encoded by the TGF-β supergene family, that promotes regeneration and differentiation of healthy dental tissue in vivo, which in turn leads to remineralization of dentin and enamel. The tissue scaffold may further include an antibiotic or anti-inflammatory agent.

Fibers, fabrics and textiles in which core-shell silica nanoparticles are incorporated are provided. The fibers, fabrics and textiles can be polymeric materials or natural cellulose-based or protein-based materials in which core-shell silica nanoparticles are incorporated. A variety of polymeric and natural materials can be employed, such as cellulose acetate, nylon, rayon, modacrylic, olefin, acrylic, polyester, polylactic acid, polylactic-co-glycolic acid (PLGA), polyurethane, aramid, wool, cotton, ramie, milk protein, soy protein, bamboo, etc. The core-shell silica nanoparticles can incorporate sensing, magnetic, thermal, electrical, chemical or RFID properties that can be imparted to the materials and that allow the materials to sense one or more conditions of interest, making them ideal for in situ sensing, treatment, or security applications.

The present invention discloses one medicinal polymer (PELGE / PELGA) nanometer particle carrier and its preparation process and use. The carrier material is PELGE material of different molecular weights, different LA / GA ratios and different PEG contents, and the nanometer PELGE / PELGA carrier particle is prepared through evaporation process. The said copolymer is self-assembled in water into nanometer particle or micelle, and its hydrophobic PLGA segment coagulates into the core while the hydrophilic polyglycol forms hydrophilic shell. The carrier may be used for the nanometer preparation of plasmid, nucleic acid vaccine, antisense oligodeoxynucleotide or ribozyme for genetic treatment; the nanometer preparation of various chemical medicines; and the nanometer preparation of polypeptide and protein medicines.

The invention relates to a novel temperature / PH dual-sensibility self-assembly segmented copolymer, i.e. polyhistidine-polylactic-co-glycolic acid-polyethyleneglycol-polylactic-co-glycolic acid-polyhistidine (OLH-b-PLGA-b-PEG-b-PLGA-b-OLH), belonging to the technical field of medicine. The self-assembly segmented copolymer accords with the structural features of a temperature / PH unika polymer, and a molecular structure of the self-assembly segmented copolymer respectively comprises a polylactic-co-glycolic acid-polyethyleneglycol-polylactic-co-glycolic acid (PLGA-b-PEG-b-PLGA) chain link which responds to temperature change and a low polyhistidine chain link which responds to PH change; copolymers can be dissolved into water under room temperature to form a free-pouring micellar solution,and when the temperature and the PH of an external environment change, the copolymers with different structural proportions are respectively expressed as follows: (1) the phase variation of solution-gelatin, and (2) the response action of the dissociation of a micellar structure, wherein the copolymer with the response action of the (1) can be taken as a carrier of an injection type sustained controlled-release drug delivery system, and the copolymer with the response action of the (2) can be taken as a carrier of a micellar target drug delivery system.

The invention discloses preparation of a polylactic-co-glycolic acid (PLGA) nano-fiber scaffold and application of the PLGA nano-fiber scaffold to tissue engineering, and belongs to the field of the tissue engineering. The method comprises the following steps of: preparing a fiber film containing two materials by taking PLGA and polyvinylpyrrolidone (PVP) as a raw material through electrostatic blended spinning, and dissolving and removing the PVP in an aqueous solution to obtain the PLGA nano-fiber scaffold with certain microstructures. A cell / PLGA nano-fiber scaffold composite matrix is obtained by the following steps of: inoculating seed cells on the PLGA nano-fiber scaffold, culturing in vitro, folding a cell / PLGA nano-fiber scaffold composite, and culturing for 7 to 14 days in a spinner cultivation mode. The composite matrix can be taken as a tissue engineering material with a specific tissue repair function and implanted into an animal model. The preparation process is simple and feasible, is high in repeatability, and can be widely applied to the field of the tissue engineering.

A porous scaffold material for tissue engineering is the composition of a polylactic acid type polymer, such as poly-L-lactic acid (PLLA), poly-D, L-lactic acid (PDLLA) and poly-L-lactic acid / hydroxyacetic acid copolymer (PLGA), and a modified nano-class hydroxyapatite (NHA). It is prepared by the thermal phase separation technique.

The invention discloses a composite membrane for guiding bone tissue regeneration and a preparation method thereof. The composite membrane comprises a basal layer, an intermediate modified layer and a functional surface layer, wherein the basal layer is a poly lactic-co-glycolic acid (PLGA) membrane, the intermediate modified layer is formed by polymerizing dopamine to form polydopamine and adsorbing the polydopamine to the surface of the PLGA membrane, and the functional surface layer is formed by reaction of I-type collagen or a collagen / chitosan mixture and active groups in the polydopamine. The preparation method for the composite membrane comprises a series of steps of membrane preparation, rinsing, airing and the like. The artificially synthesized macromolecular polymer is used as a basal material, the surface of the membrane obtained after the basal material is grafted with a natural polymer to undergo surface function activation and functional modification has a nano structure and active groups which are not owned by the original synthesized polymer, the affinity of osteoblasts is improved, and adhesion and proliferation of cells are promoted; and by using the synthesized macromolecular polymer as the base, high mechanical strength and controllable degradability are provided, and the grafted natural polymer is combined with the base firmly by pre-modification of the surface of the synthesized macromolecular polymer.