1936 results about "Lactide" patented technology

A water soluble, biodegradable ABA- or BAB-type tri-block polymer is disclosed that is made up of a major amount of a hydrophobic A polymer block made of a biodegradable polyester and a minor amount of a hydrophilic polyethylene glycol(PEG) B polymer block, having an overall average molecular weight of between about 2000 and 4990, and that possesses reverse thermal gelation properties. Effective concentrations of the tri-block polymer and a drug may be uniformly contained in an aqueous phase to form a drug delivery composition. At temperatures below the gelation temperature of the tri-block polymer the composition is a liquid and at temperatures at or above the gelation temperature the composition is a gel or semi-solid. The composition may be administered to a warm-blooded animal as a liquid by parenteral, ocular, topical, inhalation, transdermal, vaginal, transurethral, rectal, nasal, oral, pulmonary or aural delivery means and is a gel at body temperature. The composition may also be administered as a gel. The drug is released at a controlled rate from the gel which biodegrades into non-toxic products. The release rate of the drug may be adjusted by changing various parameters such as hydrophobic/hydrophilic component content, polymer concentration, molecular weight and polydispersity of the tri-block polymer. Because the tri-block polymer is amphiphilic, it functions to increase the solubility and/or stability of drugs in the composition.

A water soluble biodegradable ABA- or BAB-type triblock polymer is disclosed that is made up of a major amount of a hydrophobic polymer made of a poly(lactide-co-glycolide) copolymer or poly(lactide) polymer as the A-blocks and a minor amount of a hydrophilic polyethylene glycol polymer B-block, having an overall weight average molecular weight of between about 2000 and 4990, and that possesses reverse thermal gelation properties. Effective concentrations of the triblock polymer and a drug may be uniformly contained in an aqueous phase to form a drug delivery composition. At temperatures below the gelation temperature of the triblock polymer the composition is a liquid and at temperatures at or above the gelation temperature the composition is a gel or semi-solid. The composition may be administered to a warm-blooded animal as a liquid by parenteral, ocular, topical, inhalation, transdermal, vaginal, transurethral, rectal, nasal, oral, pulmonary or aural delivery means and is a gel at body temperature. The composition may also be administered as a gel. The drug is released at a controlled rate from the gel which biodegrades into non-toxic products. The release rate of the drug may be adjusted by changing various parameters such as hydrophobic/hydrophilic componenet content, polymer concentration, molecular weight and polydispersity of the triblock polymer. Because the triblock polymer is amphiphilic, it functions to increase the solubility and/or stability of drugs in the composition.

An acid fracturing method is provided in which the acid is generated in the fracture by hydrolysis of a solid acid-precursor selected from one or more than one of lactide, glycolide, polylactic acid, polyglycolic acid, a copolymer of polylactic acid and polyglycolic acid, a copolymer of glycolic acid with other hydroxy-, carboxylic acid-, or hydroxycarboxylic acid-containing moieties, and a copolymer of lactic acid with other hydroxy-, carboxylic acid or hydroxycarboxylic acid-containing moieties. The solid acid-precursor may be mixed with a solid acid-reactive material to accelerate the hydrolysis and/or coated to slow the hydrolysis. Water-soluble liquid compounds are also given that accelerate the hydrolysis. The method ensures that the acid contacts fracture faces far from the wellbore.

A drug eluting medical device is provided for implanting into vessels or luminal structures within the body of a patient. The coated medical device, such as a stent, vascular, or synthetic graft comprises a coating consisting of a controlled-release matrix of a bioabsorbable, biocompatible, bioerodible, biodegradable, nontoxic material, such as a Poly(DL-Lactide-co-Glycolide) polymer, and at least one pharmaceutical substance, or bioactive agent incorporated within the matrix or layered within layers of matrix. In particular, the drug eluting medical device when implanted into a patient, delivers the drugs or bioactive agents within the matrix to adjacent tissues in a controlled and desired rate depending on the drug and site of implantation.

The present invention is directed to disposable composite downhole tool formed of a resin-coated fiber. The fiber is formed of a degradable polymer, such as a poly(lactide) or polyanhydride. The resin is formed of the same degradable polymer as the fiber. It chemically bonds to the fiber, thereby making a strong rigid structure once cured. The fiber may be formed into a fabric before being coated with the resin. Alternatively, the fiber is formed of a non-biodegradable material.

The present invention provides bioactive polymer compositions that can be formulated to release a wound healing agent at a controlled rate by adjusting the various components of the composition. The composition can be used in an external wound dressing, as a polymer implant for delivery of the wound healing agent to an internal body site, or as a coating on the surface of an implantable surgical device to deliver wound healing agents that are covalently attached to a biocompatible, biodegradable polymer and/or embedded within a hydrogel. Methods of using the invention bioactive polymer compositions to promote natural healing of wounds, especially chronic wounds, are also provided. Examples of biodegradable copolymer polyesters useful in forming the blood-compatible, hydrophilic layer or coating include copolyester amides, copolyester urethanes, glycolide-lactide copolymers, glycolide-caprolactone copolymers, poly-3-hydroxy butyrate-valerate copolymers, and copolymers of the cyclic diester monomer, 3-(S)[(alkyloxycarbonyl)methyl]-1,4-dioxane-2,5-dione, with L-lactide. The glycolide-lactide copolymers include poly(glycolide-L-lactide) copolymers formed utilizing a monomer mole ratio of glycolic acid to L-lactic acid ranging from 5:95 to 95:5 and preferably a monomer mole ratio of glycolic acid to L-lactic acid ranging from 45:65 to 95:5. The glycolide-caprolactone copolymers include glycolide and ε-caprolactone block copolymer, e.g., Monocryl or Poliglecaprone.

Coatings are provided in which surfaces may be activated by covalently bonding a silane derivative to the metal surface, covalently bonding a lactone polymer to the silane derivative by in situ ring opening polymerization, and depositing at least one layer of poly(lactide-co-caprolactone) copolymer on the bonded lactone. Biologically active agents may be disposed with the poly(lactide-co-caprolactone) copolymer layers. Such coated surfaces may be useful in medical devices, in particular stents.

The present invention is directed to a hemostatic textile, comprising: a material comprising a combination of glass fibers and one or more secondary fibers selected from the group consisting of silk fibers; ceramic fibers; raw or regenerated bamboo fibers; cotton fibers; rayon fibers; linen fibers; ramie fibers; jute fibers; sisal fibers; flax fibers; soybean fibers; corn fibers; hemp fibers; lyocel fibers; wool; lactide and/or glycolide polymers; lactide/glycolide copolymers; silicate fibers; polyamide fibers; feldspar fibers; zeolite fibers, zeolite-containing fibers, acetate fibers; and combinations thereof; the hemostatic textile capable of activating hemostatic systems in the body when applied to a wound. Additional cofactors such as thrombin and hemostatic agents such as RL platelets, RL blood cells; fibrin, fibrinogen, and combinations thereof may also be incorporated into the textile. The invention is also directed to methods of producing the textile, and methods of using the textile to stop bleeding.

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 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.

Packaging laminate for packages for liquid foods having excellent liquid and oxygen gas barrier properties in which all included layers are biodegradable. The packaging laminate includes at least one liquidtight layer (11, 13) of homo or copolymers of monomers selected from a group consisting of lactic acid, glycol acid, lactide, glycolide, hydroxy butyric acid, hydroxy valeric acid, hydroxy caproic acid, valerolactone, butyrolactone and caprolactone, as well as an oxygen gas barrier layer (12) of ethylene vinyl alcohol, polyvinyl alcohol, starch or starch derivatives. The oxygen gas barrier layer is preferably applied by a dispersion coating process. The layers may be laminated directly to one another or indirectly by means of interjacent adhesive layers. The packaging laminate may also include a core layer of, for example, paper or paperboard, or a biopolymer. The invention also realises a method of producing the biodegradable packaging laminate according to the invention.

Blends made of bioabsorbable materials including glycolide, lactide, caprolactone, dioxanone, trimethylene carbonate, alkylene glycols, esteramides, etc., and polymers and copolymers thereof with cyanoacrylates are described. Processes for making the polymers and surgical articles made totally or in part from such polymers, including sutures, are also described.

A semi-crystalline film comprised of a lactide polymer. The lactide polymer comprises a plurality of poly(lactide) polymer chains, residual lactide in concentration of less than about 5 percent and water in concentration of less than about 2000 parts-per-million. A process for manufacturing a semi-crystalline film with the lactide polymer composition is also disclosed.

Septal defect occluders are disclosed which can be used with a catheter deployment system to occlude a septal defect. The septal defect occluders of the present invention comprise a metallic frame structure that supports a biodegradable member. The frame structure is made from a shape memory metal such as Nitinol. The frame forms two opposing umbrella or disc shaped halves that are connected via a central region. The biodegradable member is attached to the umbrella or disc shaped halves and can be any of numerous biodegradable materials and is preferably a co-polymer of glycolide and lactide. This material initially forms a barrier to blood flow that occludes the defect. Over time, this material is replaced by the body with scar tissue formation and endothelial cells. The metal frame is left coated with the body's own material that blocks the defect.

As a treatment for angiostenosis, angioplasty (PTA or PTCA) of expanding a small-sized balloon in a vessel has been commonly conducted. However, this treatment easily causes repeated stenosis (restenosis) after the treatment. Placement of a stent in a vessel is also effective in decreasing restenosis, but this treatment may also cause restenosis. The present invention provides a stent containing a poly (lactide-co-glycolide) or both a poly (lactide-co-glycolide) and an immunosuppressive agent in at least a portion of a surface of the stent, and further containing a material nondegradable in vivo.

An adhesion-preventive film is provided that is excellent in flexibility and can prevent cracks from occurring. The adhesion-preventive film contains a copolymer of lactide and caprolactone. The lactide and the caprolactone of the copolymer has a mole ratio in the range of 65:35 to 80:20. Even when this adhesion-preventive film is used in a curved state in vivo or is wound around an affected part such as a tendon, for example, it can provide an adhesion-preventive function for a sufficiently long period without cracking.

The present invention provides an amorphous terpolymer for a coating on an implantable device for controlling release of drug and methods of making and using the same.

Controlled release of hydrophobic bioactive substances in vivo over an extended time period and without "bursts" of drug release is achieved using a liquid polymeric composition including a polymer such as poly(lactide-co-glycolide) copolymer in a mixture of hydrophilic and lipophilic solvents.

The invention provides, inter alia, immunogenic compositions comprising a first antigen, at least two adjuvants, wherein a first adjuvant comprises a polymer derived from poly(lactides) and/or poly(lactide-co-glycolides), and wherein a second adjuvant comprises an imidazoquinoline, wherein said first antigen is encapsulated within, adsorbed or conjugated to, co-lyophilized or mixed with said first adjuvant, and a pharmaceutically acceptable excipient, wherein said composition elicits a cellular immune response when administered to a vertebrate subject. The invention also provides methods of producing immunogenic compositions, methods for producing a cytotoxic-T lymphocyte (CTL) response in a vertebrate subject, and methods of immunization.

Novel bioabsorbable polymeric blends are disclosed. The blends have a first component that is a polylactide polymers or a copolymer of lactide and glycolide and a second component that is poly(p-dioxanone) polymer. The novel polymeric blends provide medical devices having dimensional stability. Also disclosed are novel bioabsorbable medical devices made from these novel polymer blends, as well as novel methods of manufacture.

A hybrid contact lens includes a substantially rigid center portion and a substantially flexible skirt portion connected to the center portion. The skirt portion is formed using xerogels compatible with diluents comprising at least one selected from polylactic acid, polyglycolic acid, lactide, glycolide, a polyacetal, a cyclic acetal, a polyketal, a cyclic ketal, a polyorthoester, a cyclic orthoester, di-t-butyl-dicarbonate, tris(trimethylsilyl)amine, and 2,2,2-trifluoroacetamide. These diluents are formulated to function as a stand-in for water in the xerogel polymer, allowing the xerogel to form and bond to the rigid center portion in its fully expanded state. Upon hydration of the hybrid lens, substantially little dimensional change, and thus substantially little distortion, is obtained in the skirt portion. The diluents of the present invention further preserve the mechanical integrity of the xerogel, allowing the xerogel to be machined to final shape, improving the dimensional tolerances which can be achieved in the hybrid lens.

Elastomers are formed from castor oil and/or ricinoleic acid estolides and a polyester formed from an epoxidized vegetable oil such as ESO and a polycarboxylic acid such as sebacic acid, optionally in the presence of a peroxide initiator, or include crosslinked reaction products derived from ricinoleic acid or castor oil estolides, epoxy group-containing compounds such as epoxy resins and/or epoxidized vegetable oil, epoxy hardeners such as polyamine and polycarboxylic acid hardeners, thermally activated free radical initiators such as peroxides, and optionally but preferably include fillers such as limestone or wood flour. The elastomers can be prepared using a two-step, solvent-less procedure at elevated or ambient temperatures. These predominantly "all-natural" elastomers have physical properties comparable to conventional petroleum-based elastomers and composites and exhibit good flexibility, resiliency, abrasion resistance and inertness to hydrolysis. The resulting elastomers display good mechanical strength and resiliency, are resistant to abrasion and hydrolysis, and can be processed into sheet materials, which makes them attractive as floor covering components.

The invention provides a risperidone slow-release microsphere, a preparation method and an application thereof. The microsphere comprises risperidone or 9-hydroxy risperidone or the salt thereof and anon-end-capped lactide-glycollide copolymer. The risperidone slow-release microsphere provided by the invention has higher medicine-carrying quantity, no in-vivo sudden-release phenomenon, stable blood concentration and no medicine release lag period, reduces the administration frequency of a patient greatly, reduces the administration volume of each time, enhances the conformance of the patientand reduces the generation of adverse reactions.