289 results about "Charged polymers" patented technology

Techniques for controlling the position of a charged polymer inside a nanopore are provided. For example, one technique includes using electrostatic control to position a linear charged polymer inside a nanopore, and creating an electrostatic potential well inside the nanopore, wherein the electrostatic potential well controls a position of the linear charged polymer inside the nanopore.

The present invention provides a medical device, preferably an ophthalmic device, more preferably a contact lens, which comprises a core material and a biocompatible LbL coating non-covalently attached to said core material. The biocompatible LbL coating comprises at least one charge/non-charge bilayer, wherein said charge/non-charge bilayer is composed of, in no particular order, one layer of a charged polymeric material and one layer of a non-charged polymeric material which is capable of being non-covalently bond to the charged polymeric material.

The present invention relates to a substrate having antimicrobial and/or antistatic properties. Such properties are imparted by applying a coating or film formed from a cationically-charged polymer composition. The polymer composition includes a noncationic ethylenically unsaturated monomer, an ethylenically unsaturated monomer capable of providing a cationic charge to the polymer composition, and a steric stabilization component incorporated into the cationically-charged polymer composition. The present invention also relates to a polymeric material comprising a base polymer blended with the above cationically-charged polymer composition.

Methods and compositions for treating or preventing microbial infection in mammals with sulfated polysaccharides wherein the polysaccharides have a degree of sulfation effective to enable maximal interaction of constituent sulfate groups with the microbe which causes the infection and wherein the sulfated polysaccharide is not substantially endocytosed or degraded by cell receptor binding in the mammal and thereby retains antimicrobial activity in vivo.

Devices for use in the regeneration or repair of body tissue (such as nerves) comprise a multi-lumen scaffold and, optionally, an outer sheath. The tissue guidance conduits are preferably formed of biocompatible, biodegradable charged polymer hydrogels, particularly charged oligo-(polyethylene glycol)fumarate hydrogels. The outer sheath is formed of a stronger material than the scaffold and preferably comprises a region at each end for suturing the device in place. Methods for making tissue guidance conduits and for repairing tissue are also described.

The present invention describes polymer nanoparticles with a cationic surface potential, in which both hydrophobic and hydrophilic pharmaceutically active substances can be encapsulated. The hydrophilic and thus water-soluble substances are encapsulated in the particle core by co-precipitation through ionic complexing with a charged polymer. Both therapeutic agents and diagnostic agents can be used as pharmaceutically active substances for encapsulation. The cationic particle surface permits stable, electrostatic surface modification with partially oppositely charged compounds, which can contain target-specific ligands for improving passive and active targeting.

The invention discloses a method for preparing low-voltage high-flux charged nano-filtration membrane by dynamic self-assembly, which is characterized in that polymer ultra-filtration membrane is taken as a basic film; polycation electrolyte and polyanion electrolyte are alternatively and dynamically self-assembled on the surface of the basic film to gain a selective separation layer and to prepare the nano-filtration membrane of charged surface; wherein, the used ultra-filtration membrane molecular weight cutoff is less than 0.1 million; the ultra-filtration membrane material is surface-charged or modified-charged polymer. Nano-filtration membrane preparation by polyelectrolyte dynamic self-assembly has high efficiency, simple and convenient method and controllable assembly process and film structure; pure water solution is used in the whole preparation process, which is green and environmental protective; the applicable polyelectrolyte has a plurality of types; the separation films with different performances can be obtained by adjusting the types of the polyelectrolyte and the assembly conditions. Furthermore, the prepared nano-filtration membrane has low operation pressure, high removal rate on high valence inorganic salts and far greater flux than the current commercial nano-filtration membrane and the nano-filtration membrane preparation method has good application prospect.

A polyelectrolyte film is provided, the polyelectrolyte film comprises an interpenetrating network of a net positively charged polymer and a net negatively charged polymer, wherein the net positively charged polymer, the net negatively charged polymer, or both contain polymer repeat units with at least two fluorine atoms.

This invention relates to a method for the encapsulation of cells in biologic compatible three dimensional scaffolds and the use of such cells encapsulated in a scaffold. The cells are embedded in a charged polymer that is complex coacervating with an oppositely charged polymer within biologic compatible scaffolds. The polymer complex embedding the cells is forming an ultra thin membrane on the surface of the three dimensional scaffold.

A medium for isolating or releasing an electrostatically charged component from or into an aqueous composition. The medium has a polyelectrolyte film on at least one surface of an article wherein the polyelectrolyte film is characterized by an interpenetrating network of a predominantly positively charged polymer and a predominantly negatively charged polymer. The predominantly positively charged polymer, the predominantly negatively charged polymer or both contain (i) a pH sensitive imidazole repeat unit having a pKa between 3 and 9, or (ii) a redox sensitive repeat unit selected from the group consisting of quaternized bipyridine repeat units, coordinated metal repeat units, pyrrole repeat units, aniline repeat units, thiophene repeat units and combinations thereof having a redox potential between +1.2 volts and −1.2 volts versus a standard hydrogen electrode.

Provided is a nanofiber spinning method and device for producing a high strength and uniform yarn made of nanofibers with high productivity and at a low cost.

The device includes: a nanofiber producing unit (2) which produces nanofibers (11) by extruding polymer solution, prepared by dissolving polymeric substances in a solvent, through small holes (7) and charging the polymer solution, and by allowing the polymer solution to be stretched by an electrostatic explosion, and which allows the nanofibers to travel in a single direction; a collecting electrode unit (3) to which an electric potential different from that of the charged polymer solution is applied, and which attracts the produced nanofibers (11) while simultaneously rotating and twisting the nanofibers, and gathers them for forming a yarn (20) made of the nanofibers (11); and a collecting unit (5) which collects the yarn (20) passed through the center of the collecting electrode unit (3).

The present invention relates to a substrate having one or more antimicrobial or antistatic properties. Such properties are imparted by applying a coating or film formed from a cationically-charged polymer composition. The polymer composition includes a noncationic ethylenically unsaturated monomer and an ethylenically unsaturated monomer capable of providing a cationic charge to the polymer composition. Optionally, the polymer composition includes a steric stabilization component incorporated into the cationically-charged polymer composition. The present invention also relates to a personal care product and polymeric material comprising a base polymer blended with the above cationically-charged polymer composition.

This invention relates to a method for immobilizing cells under laminar flow conditions in a matrix formed by biocompatible charged polymers, to a flow device for the use with the method of the present invention, and to uses of the polymer matrices containing the cells immobilized using the method of the present invention.

A microfluidic device for carrying a liquid, the device comprising a microfluidic channel having an interior wall and a polyelectrolyte film on the interior wall whereby liquid carried by the channel contacts the polyelectrolyte film, the polyelectrolyte film having a thickness of about 1 to about 1000 nanometers and comprising an interpenetrating network of a predominantly positively charged polymer and a predominantly negatively charged polymer, the predominantly positively charged polymer, the predominantly negatively charged polymer or both containing (i) a pH insensitive positively or negatively charged repeat unit having a pKa greater than 9 or less than 3, and (ii) a pH sensitive repeat unit, the pH sensitive repeat unit having a pKa of 3 to 9, whereby the pH of liquid in the microfluidic channel may be used to control the velocity or direction of electroosmotic flow of the liquid within said microfluidic channel.

The invention relates to hyaluronic acid nanoparticles for the administration of at least one active ingredient. The inventive nanoparticles comprise hyaluronic acid in salt form a positively-charged polymer, a polyanionic salt and at least one active ingredient. The method of obtaining the aforementioned nanoparticles comprises the following steps consisting in: preparing an aqueous solution of a hyaluronic acid salt, preparing an aqueous solution of a cationic polymer, adding a polyanionic salt to the solution of the hyaluronic acid salt, and stir-mixing said solutions such as to produce the nanoparticles, the active ingredient being dissolved in one of the initial solutions or in the suspension of nanoparticles obtained in order to be absorbed on the nanoparticles. The invention also relates to pharmaceutical and cosmetic compositions comprising the above-mentioned nanoparticles.

Carbon nanotubes, associated with a charged dispersant are aligned on a substrate by deposition on the substrate directly from solution. Preferred dispersants are charged polymers such as biopolymers.

The disclosure provides a novel system of storing information using a charged polymer, e.g., DNA, the monomers of which correspond to a machine-readable code, e.g., a binary code, and which can be synthesized and/or read using a novel nanochip device comprising nanopores; novel methods and devices for synthesizing oligonucleotides in a nanochip format; novel methods for synthesizing DNA in the 3′ to 5′ direction using topoisomerase; novel methods and devices for reading the sequence of a charged polymer, e.g., DNA, by measuring capacitive or impedance variance, e.g., via a change in a resonant frequency response, as the polymer passes through the nanopore; and further provides compounds, compositions, methods and devices useful therein.

The invention discloses a method for preparing therapeutic substance-loaded microcapsules. The method applies the high-voltage electrostatic spray principle and comprises the steps of leading therapeutic substance-loaded charged polymer solution to instantaneously form ultrafine gel particles under the high-voltage electrostatic action, leading a mist of the particles to be received by polymer solution charged with opposite charges, leading a surface layer of the gel particles to be wrapped by a polymer gel shell layer of the opposite charges, forming structures of capsule cores and capsule walls, further filtering by a microporous membrane, and obtaining the therapeutic substance-loaded microcapsules. Microstructures and scale of the capsule cores and the capsule walls can be precisely controlled through voltage, solution concentration and distance from a jet orifice to receiving solution, and therapeutic substances are bound by the capsule cores and the capsule walls, thereby forming controlled release and improving therapeutic efficacy. The method has the advantages of simple and feasible process and good repeatability, the whole process of the preparation process is clean and pollution-free, the provided in-situ therapeutic substance-loaded microcapsules do not need the complex post-processing, the particle size is controllable, and the release rate of the therapeutic substances is convenient to control, thereby having good application prospect.

This invention especially relates to the synthesis of reversible semi-interpenetrating pH sensitive hydrogel by template copolymerization. For the synthesis, a pH sensitive ionic monomer is elected and an opposite-charged polymer is adopted as template. The two are copolymerized to obtain a gel product, where there exist not only covalent bond cross-links but also ionic bond cross-links by electrostatic bonding interaction so that both the gel strength and the pH sensitivity are enhanced. As there are pH sensitive ionic monomer units is the copolymer, ionic density varies with pH value of the solution; when the ionic density reaches a certain value, the gel begins to swell. And thanks to the existence of opposite charged ionic template polymer in the gel, the threshold of pH sensitivity can be adjusted.

In one aspect of the present invention, a method of fabricating a composite membrane includes: forming a first polymer solution from a first polymer and a second polymer solution from a second polymer, respectively, where the first polymer includes a charged polymer and the second polymer includes an uncharged polymer; electrospinning, separately and simultaneously, the first and second polymer solutions to form a dual fiber mat with first polymer fibers and second polymer fibers; and processing the dual fiber mat by softening and flowing one of the first or second polymer fibers to fill in the void space between the other of the first and second polymer fibers so as to form the composite membrane. In some embodiments, the composite membrane may be a proton exchange membrane (PEM) or an anion exchange membrane (AEM).

The concentration of an anionically charged polymer in an aqueous solution is determined with a thin solid film having a polymer matrix and a cationic dye. A sample of an aqueous solution containing at least one anionically charged polymer to be tested is applied to the film sensor. The absorbance of the film sensor is measured after the sample has been applied. The absorbance of the film sensor is then compared with a calibration curve of the absorbance of samples containing known concentrations of the anionically charged polymers to determine the concentration of anionically charged polymer in the sample.

The invention discloses an electrostatic spinning device for manufacturing nano fibers in an electromagnetic field with a coupling method. The electrostatic spinning device comprises a material basket, a piston, a spinning nozzle, a high-voltage power supply device, a receiving plate and a grounding power line. The electrostatic spinning device further comprises an electric conduction coil arranged between the spinning nozzle and the receiving board and right opposite to the spinning nozzle and the receiving board. Two electromagnets are arranged on the receiving board in parallel. The orientation of nano fibers collected by electrified polymer solutions is greatly improved under the action of the electromagnetic field which is large enough. Meanwhile, the positively charged coil is added in the flow jetting process of polymers, jet flow can be stabilized, the range of a Taylor cone is reduced, and the degree of order of the nano fibers is further improved. The electrostatic spinning device for manufacturing the nano fibers in the electromagnetic field with the coupling method is simple in structure, convenient to operate, easy to control and short in technological process.