977 results about "N-n-propylacrylamide" patented technology

Polymeric nanoparticles with a hydrophobic core and a hydrophilic shell are formed from: 1) N-isopropyl acrylamide (NIPAAM), at a molar ratio of about 50% to about 90%, and preferably 60% for specific delivery routes such as oral or parenteral; either water-soluble vinyl derivatives like vinylpyrolidone (VP) or vinyl acetate (VA), or water insoluble vinyl derivatives like methyl methacrylate (MMA) or styrene (ST), at a molar ratio of about 10% to about 30%; and acrylic acid (AA), at a molar ratio of about 10% to about 30%. The formed nanoparticles may be optionally surface functionalized using reactive groups present in AA, including PEGylation, or conjugation of moieties such as chemotherapeutics, contrasting agents, antibodies, radionucleides, ligands, and sugars, for diagnostic, therapeutic, and imaging purposes. The polymeric nanoparticles are preferably dispersed in aqueous solutions. The polymeric nanoparticles incorporate one or more types of medicines or bioactive agents in the hydrophobic core; on occasion, the medicine or bioactive agent may be conjugated to the nanoparticle surface via reactive functional groups. The polymeric nanoparticles are capable of delivering the said medicines or bioactive agents through oral, parenteral, or topical routes. The polymeric nanoparticles allow poorly water soluble medicines or bioactive agents, or those with poor oral bioavailability, to be formulated in an aqueous solution, and enable their convenient delivery into the systemic circulation.

The invention discloses a nanometer plural gel and a preparation method thereof. The preparation method comprises the following steps of: (1) preparing a polymer into a film in a mould, and then solidifying or cross-linking to obtain a polymer gel film; and (2) adding a nanometer material, N-isopropylacrylamide, a cross-linking agent and an initiating agent to water to obtain a mixed solution, adding the mixed solution to the mould with the polymer gel film, and carrying out polymerization reaction and cross-linking reaction under the irradiation of an ultraviolet lamp to obtain the nanometer plural gel. The nanometer plural gel provided by the invention has a double-layer structure; and PNIPAAm gel which contains nanometer particles can generate the temperature and volume change of a specific area under illumination due to photothermal effect and can integrally generate response behaviors, such as bending and the like.

The invention provides a solution to the above mentioned problem in that it provides a catheter balloon comprising a flexible coating on its outer surface wherein a plurality of microparticles are contained wherein said coating comprises a material selected from the group consisting of poly(N-vinyl-pirrolidone, poly(N-vinyl-pirrolidone-co-butylacrylate), poly(-vinyl pyridine), polyacrylamides, e.g. poly(N-isopropylacrylamide), poly(amido-amines), poly(ethylene imine), poly(ethylene oxide-block-propylene oxide), poly(ethylene oxide-block-propylene oxide-block-ethylene oxide), poly(styrene-block-isobutylene-block-styrene), poly(hydroxystyrene-block-isobutylene-block-hydroxystyrene), polydialkylsiloxanes, polysaccharides, polyacrylates and polyalkylmethacrylates, e.g. polymethylmethacrylate and poly(2-hydroxyethylmethacrylate) and wherein said microparticles comprise a material selected from the group consisting of polyesters, e.g. poly(lactic acid), poly(lactic-co-glycol acid), poly(glycolic acid), poly(3-hydroxybutyrate), poly(3-hydroxyvalerate), poly(3-hydroxybutyrate-co-3-hydroxyvalerate) and polycaprolactone, polyamides, polysaccharides, polyurethanes, polyalkylmethacrylates and polyacrylates, e.g. polymethylmethacrylate and poly(2-hydroxyethylmethacrylate) and wherein the microparticles comprise a pharmaceutically active compound.

A temperature responsive intelligent face mask and preparation method thereof wherein a chitosan modified temperature sensitive isopropyl acryl amide / polyurethane copolymer hydrogel is grafted to a cellulose fiber. The advantages lie in that the intelligent hydrogel can swell and contract reversibly near body temperature, and the high-temperature dehydration phenomenon may be inhibited by the introduction of the polyurethane, the non-woven fabric exerts a supporter function by grafting the isopropyl acryl amide / polyurethane copolymer hydrogel thereto and as a result the strength of the gel is increased, the coupling of the natural chitosan to external surface of the gel film not only improves the face mask comfort, the skin affinity, but also offers the bacteria resistant ability. The gel face mask carries multiple nutrients and the carried nutrient and moisture may release intelligently through gel contraction under body temperature, meanwhile the temperature responsive intelligent face mask can be utilized in a plurality of times to satisfy the personalized requirement.

Provided herein is a hydrogel composition comprising a graphene, a chitosan, and a polyethylene (glycol) diacrylate (PEGDA) (PCG hydrogel). In some embodiments, the hydrogel further comprises a N-isopropylacrylamide (NIPAM) (TPCG hydrogel). Also provided is a method for differentiating a mesenchymal stem cell comprising contacting the cell with the PCG hydrogel. Further provided herein is a method for delivering a pharmaceutical composition to a cell comprising administering to the cell a TPCG hydrogel and the pharmaceutical composition.

Injectable hydrogel microspheres are prepared by forming an emulsion where hydrogel precursors are in a disperse aqueous phase and polymerizing the hydrogel precursors. In a preferred case, the hydrogel precursors are poly(ethylene glycol) diacrylate and N-isopropylacrylamide and the continuous phase of the emulsion is an aqueous solution of dextran and a dextran solubility reducer. The microspheres will load protein, e.g., cytokines, from aqueous solution.

The invention discloses thermosensitive hydrogel loaded with copper metal organic skeleton nanoparticles and a preparation method of the thermosensitive hydrogel. The preparation method comprises thesteps that an amino group on gelatin and methacrylic anhydride are subjected to acylation reaction to synthesize methylacrylic esterified gelatin with a branch containing a carbon-carbon double bond,the carbon-carbon double bond on the branch and N-isopropyl acrylamide are subjected to free radical polymerization, and methylacrylic esterified gelatin-g-poly N-isopropyl acrylamide is prepared; 1,3,5-benzene tricarbonic acid and copper acetate monohydrate are used for preparing copper-based MOF nanoparticles; the copper-based MOF nanoparticles are added to a methylacrylic esterified gelatin-g-poly N-isopropyl acrylamide solution, and a product is prepared. Copper ions are embedded in the biodegradable thermosensitive hydrogel in the form of HKUST-1 NPs, controlled slow release of the copperions is achieved, cytotoxicity is effectively reduced, migration of in-vitro dermal cells is promoted, angiogenesis is induced, and wound healing is promoted.

The invention discloses a preparation method of double-layer water gel with salt-temperature dual response. The method comprises the following steps of adding N-isopropylacrylamide, amphoteric ion monomers, cross-linking agents, photoinitiators, radical initiators and catalysts into water; performing stirring dissolution to obtain reaction liquid; performing polymerization reaction on the reactionliquid under inert gas protection and UV-irradiation; performing crosslinking for 1 to 5 hours to obtain poly-N-isopropylacrylamide and amphoteric ion polymer double-layer water gel. Great differences of two kinds of functional monomers in aspects of polarity and polymerization speed are utilized; the double-layer water gel with the salt-temperature dual response is prepared by a one-step method;the double-layer water gel can realize fast great-amplitude self periodic deformation in water-slat solution and low-temperature / high-temperature environment. The water gel can be used for being madeinto a soft body robot or sensor element realizing the salt-temperature dual response.

The present invention includes a method for preparing polymer hydrogel spherical particles on a nanometer scale (nanogels). The method includes encapsulating hydrogel-forming components into liposomes, diluting the large unilamellar liposomes suspension to prevent polymerization outside the liposomes, and polymerizing the encapsulated hydrogel-forming components. The lipid bilayer may be solubilized with detergent. The phospholipid and detergent molecules and their micelles may then be removed by dialysis. The resulting nanogels may then be dried by evaporation in a temperature gradient. Poly(acrylamide), poly(N-isopropylacrylamide), and poly(N-isopropylacrylamide-co-1-vinylimidazole) hydrogel particles with a diameter from 30 to 300 nm were detected and characterized by dynamic light scattering technique. The solvent, temperature, pH, and ionic sensitivities of the nanogels were studied.

The invention relates to high-strength temperature-sensitive hydrogel as well as a preparation method and application thereof. The high-strength temperature-sensitive hydrogel is prepared by copolymerizing 2-vinyl-4,6-diamino-1,3,5-triazine and N-isopropyl acrylamide as raw materials in the presence of a cross-linking agent and an initiator, wherein the mass ratio of the 2-vinyl-4,6-diamino-1,3,5-triazine as a monomer to the N-isopropyl acrylamide is 0.2-2:1. The high-strength temperature-sensitive hydrogel has high stretching and compression resistance and favorable biocompatibility and optical property, and the surface of the hydrogel has the capacities of adsorbing DNA (Deoxyribonucleic Acid) transfection cells and regulating the attaching and disattaching behaviors of the cells through temperature. The preparation method of the hydrogel is simple, and the hydrogel is easy to store for a long term and transport for a long distance.

A preparation method of a thermosensitive microgel asymmetric supported nano silver catalyst comprises the steps of preparing poly-(N-isopropylacrylamide-styrene) / poly-(N-isopropylacrylamide-methacrylic acid) core-shell microgel by a soap-free emulsion polymerization method and a seed emulsion polymerization method, and then synthesizing the asymmetric supported nano silver catalyst taking the microgel as a template by a pickering emulsion template method. The thermosensitive microgel asymmetric supported nano silver catalyst prepared by the method shows good thermosensitivity, and good catalytic activity as the catalytic reaction efficiency is regulated and controlled by temperature and the thermosensitivity of the microgel simultaneously during catalytic reduction of p-nitrophenol.

The invention relates to a poly(N-isopropyl acrylamide)-polyurethane-polypeptide block-graft copolymer and a preparation method thereof. In the copolymer, the molecular weight of polyurethane is 10000-60000; the molecular weight of poly(N-isopropyl acrylamide) is 3000-10000; and the molecular weight of polypeptide is 500-4000. The preparation method comprises the steps: 1) synthesis of polyurethane containing side carboxyl group and terminal double-bond group: adding diisocyanate, polypropylene glycol, polyethylene glycol, a catalyst and a solvent to a reaction bottle and reacting, then sequentially adding bis(hydroxymethyl) propanoic acid, butylene glycol and hydroxypropyl acrylate and reacting; 2) synthesis of poly(N-isopropyl acrylamide)-polyurethane block copolymer: adding polyurethane containing side carboxyl group and terminal double-bond group, a solvent and an initiator, and isopropyl acrylamide to a reactor and reacting; and 3) adding poly(N-isopropyl acrylamide)-polyurethane block copolymer, a solvent, a condensing agent, and a polypeptide homopolymer to a reactor and reacting to obtain a target product with temperature and pH dual responsibility.

The invention relates to a preparation method of a double-hydrophilic temperature response polymer. The method comprises the following steps of: (1) preparing aliphatic diacid divinyl ester; (2) dissolving the aliphatic diacid divinyl ester and glucose into an organic solvent, and adding bacillus subtilis alkali protease or lipase AY30 to obtain a polymerizable saccharine hydrophilic monomer; and (3) dissolving the polymerizable saccharine hydrophilic monomer, an N-isopropylacrylamide monomer and an initiator into an organic solvent, performing a polymerization reaction under the protection of nitrogen gas at the temperature of 50-80 DEG C to obtain a polymer, repeatedly precipitating, and performing vacuum drying on an obtained precipitant to obtain the double-hydrophilic temperature response polymer. The method is simple, has mild reaction conditions, is easy, convenient and practicable for operating, and is easy for industrializing; and the obtained double-hydrophilic temperature response polymer can be applied in the fields of medicament targeted conveying, gene delivery, biological separation, membrane science and the like.

The invention relates to a preparation method of a semi-interpenetrating network nanocomposite hydrogel which can respond to variations in temperature, pH and ultraviolet to realize volume transition. The preparation method of the gel is as follows: taking temperature-sensitive monomers, namely N-isopropylacrylamide and azo type water soluble monomers, namely 4-((4-acryloxy) phenyl azo) benzoic acid as copolymerization monomers, taking modified nano-clay as a cross-linking agent, dissolving the monomers and the cross-linking agent in a cellulose type macromolecular water solution, uniformly stirring, and then performing oxidation, reduction and catalytic free radical polymerization in an ice bath under the protection of nitrogen for preparation. The gel uses nano-laponite cross-linked monomers to constitute a framework of the gel and takes cellulose type macromolecules as semi-interpenetrating macromolecules. The obtained hydrogel has the advantages of excellent mechanical properties, high swelling rate and fast and controllable stimulus response. The gel has the potential to be applied to the field of sustained release of medicaments.