206 results about "Polymeric nanoparticles" patented technology

This invention relates to polymeric nanoparticles useful for drug delivery with target molecules bonded to the surface of the particles and having sizes of up to 1000 nm, preferably 1 nm to 400 nm, more preferably 1 nm to 200 nm, that are dispersed homogeneously in aqueous solution. The target drug/target substance is covalently bonded to the novel polymeric nanoparticles to secure them from outer intervention in vivo or cell culture in vitro until they are exposed at the target site within the cell. This invention also relates to microemulsion polymerization techniques useful for preparing the novel nanoparticles.

The present invention provides compositions and methods for inhibiting adhesions. The methods involve administering solutions containing hydrogel precursors such as polysaccharide derivatives, e.g., derivatives of hyaluronic acid, cellulose, or dextran, to a subject at a site where adhesions may form, e.g., as a consequence of surgery, injury, or infection. The hydrogel precursors, e.g., polysaccharide derivatives, become crosslinked following their administration to form a hydrogel that maintains tissue separation. In certain embodiments of the invention one or both solutions contains particles, e.g., polymeric nanoparticles or microparticles, so that a composite hydrogel containing the particles is formed. The solution(s), particle(s), or both, may contain a biologically active agent such as an agent that contributes to inhibiting adhesions. The biologically active agent may be covalently attached to a hydrogel precursor.

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 invention relates to polymeric nanoparticles, particularly useful in drug and agent delivery, as well as for imaging and diagnosis. The polymeric nanoparticles of the present invention comprise cross-linkers that, when degraded, leave simple linear polymeric molecules that can be excreted by the body. The present invention also relates to methods of producing the polymeric nanoparticles of the present invention, and methods of using them in drug and agent delivery, as well as imaging and diagnosis.

Polymeric nanoencapsulation methods, which combine sonication and nonsolvent temperature induced crystallization, are provided. The steps include (a) providing active agent nanoparticles having an average diameter between about 5 and about 100 nm; (b) treating said active agent nanoparticles (e.g., a superparamagnetic material) with an anionic surfactant to form modified active agent nanoparticles; (c) mixing the modified active agent nanoparticles with a solution of a polymer in a solvent at a first temperature, which is greater than the melting temperature of the polymer and less than the boiling point of the solvent to form a first mixture, said mixing comprising the use of sonication; (d) mixing a non-solvent with the first mixture to form a second mixture, the non-solvent being a non-solvent for the solvent and for the polymer and having a boiling point greater than the melting temperature of the polymer; (e) sonicating the second mixture to form an emulsion; and (f) cooling the emulsion to a second temperature and at a rate effective to precipitate polymeric nanoparticles comprising the polymer with the modified active agent nanoparticles dispersed therein.

Nanoparticles that facilitate imaging of biological tissue and methods for formulating the nanoparticles are provided. In order to form suitable nanoparticles for imaging, an anionic surfactant may be applied to superparamagnetic nanoparticles to form modified nanoparticles. The modified nanoparticles may be mixed with a polymer in a solvent to form a first mixture, and a non-solvent may be mixed with the first mixture to form a second mixture. An emulsion may be formed from the second mixture and the polymeric nanoparticles may be isolated from the emulsion. In certain embodiments of the invention, an antibody may be attached to the polymeric nanoparticles to facilitate attachment of the nanoparticles to biological tissue.

The present invention provides a rubber composition comprising (a) a liquid polymer, (b) polymer nanoparticles, and (c) a rubbery matrix. The composition may comprise less or even no aromatic oil. Rubber articles manufactured from such composition, such as tires and power belts, have gained improved reinforcement and controllable hysteresis properties.

This invention discloses a process for synthesizing a hairy polymer particle which comprises the steps of (1) polymerizing a vinyl aromatic monomer by emulsion polymerization in an aqueous medium to produce core particles, (2) recovering the core particles from the aqueous medium, (3) dispersing the core particles in an organic solvent, (4) adding an organo-lithium compound to the dried core particles in the organic solvent to produce the hairless core initiator, and (5) utilizing the hairless core initiator to initiate the anionic polymerization of a conjugated diolefin monomer in an organic solvent to produce a solution of the hairy polymer particles. The hairy polymer nanoparticles can then be recovered from the organic solvent. These hairy polymer particles are comprised of (1) a core which is comprised of a polymer of a vinyl aromatic monomer and (2) hairs which are polymer chains of a conjugated diolefin monomer, wherein the hairs are covalently bonded to the core. The core is typically spherical in shape, has a diameter of less than 1000 nm, and is comprised of a crosslinked polymer of a vinyl aromatic monomer. The hairy polymer particles of this invention are useful as fillers in rubber compositions used in making articles of manufacture, such as tires, hoses, power transmission belts, windshield wiper blades, and the like.

The present invention provides polymeric nanoparticles comprising triblock and optionally diblock copolymer chains. The architecture of the polymeric nanoparticles may be controlled, resulting in nanoparticles having non-spherical shapes. The present invention also provides a method of preparing the polymeric nanoparticles and a rubber article such as a tire manufactured from a formulation comprising the polymer nanoparticles.

Disclosed is a novel polymeric nanoparticle adhesive composite including a nanoparticle filler and method for the production thereof. More particularly, the disclosure describes the use of nanoparticle fillers, including a novel halloysite nanoparticle filler which utilizes generally cylindrical or tubular nanoparticles (e.g. rolled scroll-like shape). The filler is effectively employed in a polymer nanoparticle adhesive composite, containing the halloysite nanoparticle or other equivalent naturally occurring nanotubular filler, in which the advantages of the nanoparticle filler are provided (e.g., reinforcement, flame retardant, etc.) while maintaining or improving mechanical performance of the adhesive composite (e.g., adhesive strength and tack)

The present invention relates to polymeric nanoparticles useful in drug and agent delivery, as well as for imaging, diagnosis and targeting. The polymeric nanoparticles of the present invention comprise polymers and cross-linkers that, when degraded, leave simple nontoxic biocompatible molecules that can be metabolized, excreted, or absorbed by the body. The present invention also relates to processes for producing the polymeric nanoparticles of the present invention, and methods of using them in drug and agent delivery, as well as imaging, diagnosis and targeting.

Compositions and methods are included for preparing a hairy polymeric nanoparticle including first and second shell block polymer arms are at least partially phase-separated and surround a polymeric core. One type of polymeric arm can have a greater polarity than the other type(s) of polymeric arms. A rubber composition including the hairy nanoparticles is also provided.

The invention relates generally to the treatment and prevention of human cancer and viral diseases. More specifically, this invention relates to development of a new generation of vaccines that rely on eliciting cellular immune responses, specifically induction of cytotoxic T lymphocytes (CTL), against cancer cells and virus-infected cells via administration of a polymeric nanoparticle containing a vaccine comprising a fusion peptide or a modified peptide. Such a fusion peptide is composed of an insertion signal sequence and a peptide derived from a tumor antigen or a viral antigen, which improves antigen presentation and induces CTL with higher efficiency against cancer cells and virus-infected cells. An exemplary peptide utilized in the invention is Mart-1:27-35 peptide.

The present invention includes compositions and methods of making an activated polymeric nanoparticle for targeted drug delivery that includes a biocompatible polymer and an amphiphilic stabilizing agent non-covalently associated with a spacer compound that includes at least one electrophile that selectively reacts with any nucleophilic on a targeting agent and places the targeting agent on the exterior surface of a biodegradable nanoshell, wherein an active agent is loaded with the nanoshell.

Methods for ex vivo administration of drugs to grafts using polymeric micro- and nanoparticles and applications for these methods are described herein. The particles contain encapsulated molecules which are released locally at the site of implantation and function to prevent graft rejection or aid in the proper adaptation of the graft to the host. The disclosed methods may be used to inhibit or reduce hyperplasia and stenosis of vascular grafts or to prevent graft rejection.

Polymeric nanoparticles encapsulating inhibitory ribonucleic acids (RNAs) and methods of their manufacture and use are provided. Advantageous properties of the nanoparticles include: 1) high encapsulation efficiency of inhibitory RNAs into the nanoparticles, 2) small size of the nanoparticles that increases cell internalization, and 3) sustained release of encapsulated inhibitory RNAs by the nanoparticles that allows for administration of an effective amount of inhibitory RNAs to cells or tissues over extended periods of time. Encapsulation efficiency of inhibitory RNAs into the nanoparticles is greatly increased by complexing the inhibitory RNAs to polycations prior to encapsulation. Methods of using the polymeric nanoparticles for treating or inhibiting diseases or disorders are provided.

The present invention provides compositions and methods for inhibiting adhesions. The methods involve administering solutions containing hydrogel precursors such as polysaccharide derivatives, e.g., derivatives of hyaluronic acid, cellulose, or dextran, to a subject at a site where adhesions may form, e.g., as a consequence of surgery, injury, or infection. The hydrogel precursors, e.g., polysaccharide derivatives, become crosslinked following their administration to form a hydrogel that maintains tissue separation. In certain embodiments of the invention one or both solutions contains particles, e.g., polymeric nanoparticles or microparticles, so that a composite hydrogel containing the particles is formed. The solution(s), particle(s), or both, may contain a biologically active agent such as an agent that contributes to inhibiting adhesions. The biologically active agent may be covalently attached to a hydrogel precursor.

There is provided a method for manufacturing carbon quantum dots. The method comprises the steps of a) providing a dispersion of self-assembled polymeric nanoparticles in a dispersion liquid. The nanoparticles comprise a copolymer, the copolymer comprising insoluble repeat units that are insoluble in the dispersion liquid and soluble repeat units that are soluble in the dispersion liquid. The nanoparticles have a core/shell structure in which a core is surrounded by a shell, the core being enriched in insoluble repeat units, and the shell being enriched in soluble repeat units. The method further comprises the step of b) carbonizing the core of the nanoparticles in the dispersion, thereby producing the desired carbon quantum dots.

The present invention relates to biodegradable medical devices such as stents manufactured from biodegradable polymeric-bioceramic nanoparticle composites. The invented medical devices include at least one bioceramic nanoparticle dispersed in at least one biodegradable polymer, wherein the said biodegradable polymers include biodegradable polyesters. The device and methods to disperse one or more bioceramic nanoparticle, wherein the said bioceramic nanoparticle include, but are not limited to, amorphous calcium phosphate (ACP), dicalcium phosphate (DCP), tricalcium phosphate (TCP), pentacalcium hydroxyl Apatite (HAp), tetracalcium phosphate monoxide (TTCP) and combinations or analogues thereof. Other embodiments include methods of fabricating biodegradable stent with said polymeric-nanoparticle composites.

Surface-modified polymeric nanoparticles (NPs), compositions for making them, and their use in drug delivery are disclosed.