31355results about "Semi-permeable membranes" patented technology

Embolic protection filters and methods of making and using such devices are disclosed. An illustrative method of making a device for filtering embolic debris from a body may include the steps of molding a filter assembly that includes a distal tip and a filter portion, forming a plurality of apertures within the filter portion, and coupling a support member to the filter assembly that is adapted to shift the filter portion between a collapsed configuration and an expanded configuration.

Novel porous PTFE membranes are described possessing a unique combination of high strength, low flow resistance, and small pore size. Additionally, unique constructions with superior filtration and venting properties incorporating porous PTFE membranes are described.

The invention relates to a microfabricated device for the rapid detection of DNA, proteins or other molecules associated with a particular disease. The devices and methods of the invention can be used for the simultaneous diagnosis of multiple diseases by detecting molecules (e.g. amounts of molecules), such as polynucleotides (e.g., DNA) or proteins (e.g., antibodies), by measuring the signal of a detectable reporter associated with hybridized polynucleotides or antigen / antibody complex. In the microfabricated device according to the invention, detection of the presence of molecules (i.e., polynucleotides, proteins, or antigen / antibody complexes) are correlated to a hybridization signal from an optically-detectable (e.g. fluorescent) reporter associated with the bound molecules. These hybridization signals can be detected by any suitable means, for example optical, and can be stored for example in a computer as a representation of the presence of a particular gene. Hybridization probes can be immobilized on a substrate that forms part of or is exposed to a channel or channels of the device that form a closed loop, for circulation of sample to actively contact complementary probes. Universal chips according to the invention can be fabricated not only with DNA but also with other molecules such as RNA, proteins, peptide nucleic acid (PNA) and polyamide molecules.

A system, method and apparatus for performing a renal replacement therapy is provided. In one embodiment, two small high flux dialyzers are connected in series. A restriction is placed between the two dialyzers in the dialysate flow path. The restriction is variable and adjustable in one preferred embodiment. The restriction builds a positive pressure in the venous dialyzer, causing a high degree of intentional backfiltration. That backfiltration causes a significant flow of dialysate through the high flux venous membrane directly into the patient's blood. That backfiltered solution is subsequently ultrafiltered from the patient from the arterial dialyzer. The diffusion of dialysate into the venous filter and removal of dialysate from the arterial dialyzer causes a convective transport of toxins from the patient. Additionally, the dialysate that does not diffuse directly into the patient but instead flows across the membranes of both dialyzers provides a diffusive clearance of waste products.

The present invention provides systems, methods and apparatuses for medical fluid delivery systems that employ a pumping cassette. In particular, the present invention provides systems, methods and apparatuses for cassette-based dialysis therapies including hemodialysis, hemofiltration, APD (including tidal modalities) and CFPD. The embodiments described include a combined pump / valve housing, a fail safe pump / valve arrangement, a cassette auto-alignment feature, a pumping membrane material, a multiplexing valve arrangement, an expert fluid pumping management system, an integral port vent and an in-line air separation chamber and combinations of each of these.

An endcap including a first plate member including a radial inner portion, a radial outer portion, and defining a longitudinal axis. The endcap also includes a flange disposed between the radial inner and outer portions of the first plate member and projecting axially along the longitudinal axis in a first direction. The endcap also includes a first seal member disposed adjacent the flange. The first seal includes a first portion thereof engaged with an axial facing surface of the first plate member and a second portion thereof engaged with a radially facing surface of the flange. The endcap further includes a second plate member disposed radially outward of the radial outer portion and a second seal member disposed adjacent the second plate member including at least a portion thereof axially spaced from the axially facing surface of the first plate member in a second direction along the longitudinal axis opposite the first direction.

A microfluidic device comprises pumps, valves, and fluid oscillation dampers. In a device employed for sorting, an entity is flowed by the pump along a flow channel through a detection region to a junction. Based upon an identity of the entity determined in the detection region, a waste or collection valve located on opposite branches of the flow channel at the junction are actuated, thereby routing the entity to either a waste pool or a collection pool. A damper structure may be located between the pump and the junction. The damper reduces the amplitude of oscillation pressure in the flow channel due to operation of the pump, thereby lessening oscillation in velocity of the entity during sorting process. The microfluidic device may be formed in a block of elastomer material, with thin membranes of the elastomer material deflectable into the flow channel to provide pump or valve functionality.

Acoustic energy is used to control motion in a fluid. According to one embodiment, the invention directs acoustic energy at selected naturally occurring nucleation features to control motion in the fluid. In another embodiment, the invention provides focussed or unfocussed acoustic energy to selectively placed nucleation features to control fluid motion. According to one embodiment, the invention includes an acoustic source, a controller for controlling operation of the acoustic source, and one or more nucleation features located proximate to or in the fluid to be controlled.

Articles comprising a fibrous support of nanofibers and an interfacially polymerized polymer layer disposed on a surface of the fibrous support are useful, e.g., as fluid separation membranes.

The invention provides an implantable membrane for regulating the transport of analytes therethrough that includes a matrix including a first polymer; and a second polymer dispersed throughout the matrix, wherein the second polymer forms a network of microdomains which when hydrated are not observable using photomicroscopy at 400× magnification or less. In one aspect, the homogeneous membrane of the present invention has hydrophilic domains dispersed substantially throughout a hydrophobic matrix to provide an optimum balance between oxygen and glucose transport to an electrochemical glucose sensor.

The invention provides an implantable membrane for regulating the transport of analytes therethrough that includes a matrix including a first polymer; and a second polymer dispersed throughout the matrix, wherein the second polymer forms a network of microdomains which when hydrated are not observable using photomicroscopy at 400× magnification or less. In one aspect, the homogeneous membrane of the present invention has hydrophilic domains dispersed substantially throughout a hydrophobic matrix to provide an optimum balance between oxygen and glucose transport to an electrochemical glucose sensor.

A plasma concentrator for producing plasma concentrate from a plasma from which erythrocytes have been substantially removed. The device comprises a concentrating chamber having an inlet port and an concentrate outlet, the concentrating chamber containing hydrogel beads and at least one inert agitator; and a concentrate chamber having an inlet communicating with the concentrator outlet through a filter, and having an plasma concentrate outlet port. A process for producing plasma concentrate from plasma from which erythrocytes have been substantially removed, comprising the steps of a) moving the plasma into a concentrating chamber containing hydrogel beads and an agitator to form a hydrogel bead-plasma mixture; b) causing the agitator to stir the hydrogel bead-plasma mixture, facilitating absorption of water by the beads from the plasma, until a hydrogel bead-plasma concentrate is formed; and c) separating the plasma concentrate from the hydrogel beads by passing the plasma concentrate through a filter. The concentrator can be one or more syringe devices coupled for multiple concentrations.

The present invention provides a method and system for efficiently producing hydrogen that can be supplied to a fuel cell. The method and system of the present invention produces hydrogen in a reforming reactor using a hydrocarbon stream and water vapor stream as reactants. The hydrogen produced is purified in a hydrogen separating membrane to form a retentate stream and purified hydrogen stream. The purified hydrogen can then be fed to a fuel cell where electrical energy is produced and a fuel cell exhaust stream containing water vapor and oxygen depleted air is emitted. In one embodiment of the present invention, a means and method is provided for recycling a portion of the retentate stream to the reforming reactor for increased hydrogen yields. In another embodiment, a combustor is provided for combusting a second portion of the retentate stream to provide heat to the reforming reaction or other reactants. In a preferred embodiment, the combustion is carried out in the presence of at least a portion of the oxygen depleted air stream from the fuel cell. Thus, the system and method of the present invention advantageously uses products generated from the system to enhance the overall efficiency of the system.

A composite membrane and method for making the same, comprising a porous support and a polyamide surface. The subject membrane provides improved flux and / or rejection rates. The subject membrane is further capable of operating at lower operating pressures. The subject method includes reacting a polyfunctional amine with a polyfunctional acyl halide to form a polyamide. The method includes the step of contacting a complexing agent with the polyfunctional acyl halide prior substantial reaction between the polyfunctional acyl halide and a polyfunctional amine. The subject process is easily adapted to commercial scale manufacturing processes and is particularly suited for making nanofiltration and reverse osmosis composite membranes.

Filter cartridge assemblies and housings are provided and include a tubular housing having an inner wall, an outer wall, a first end, and a second end. The housings include inner walls with shoulders or other radially-inwardly extending flow directors at the intersections of adjacent sections of the tubular body. The assemblies include a plurality of filter media sections within the housing, and each of the plurality of filter media sections preferably has a different filter media composition. One or more of the filter media sections traverses one or more of the shoulders or other radially-inwardly extending flow directors such that the flow directors evenly direct the flow of fluid through the assembly. The assemblies find particular applicability in dialysis systems.

This invention relates to methods for reducing the presence of a compound in an ionically conductive material, e.g., for use in iontophoretic devices, wherein the presence of the compound interferes with detecting a selected analyte. Removal of the compound can typically take place either during or after the manufacture of the ionically conductive material or an assembly comprising this material. Also disclosed are methods for generating selectively permeable barriers on the reactive faces of electrodes. Further, this invention relates to hydrogels comprising one or more biocides, as well as assemblies containing such hydrogels.

Photovoltaic devices, such as solar cells, and methods for their manufacture are disclosed. A device may be characterized by an architecture having a nanostructured template made from an n-type first charge transfer material with template elements between about 1 nm and about 500 nm in diameter with about 1012 to 1016 elements / m2. A p-type second charge-transfer material optionally coats the walls of the template elements leaving behind additional space. A p-type third charge-transfer material fills the additional space volumetrically interdigitating with the second charge transfer material.

A compound comprising a composition Ax(M′1-aM″a)y(XD4)z, Ax(M′1-aM″a)y(DXD4)z, or Ax(M′1-aM″a)y(X2D7)z, and have values such that x, plus y(1-a) times a formal valence or valences of M′, plus ya times a formal valence or valence of M″, is equal to z times a formal valence of the XD4, X2D7, or DXD4 group; or a compound comprising a composition (A1-aM″a)xM′y(XD4)z, (A1-aM″a)xM′y(DXD4)z(A1-aM″a)xM′y(X2D7)z and have values such that (1-a)x plus the quantity ax times the formal valence or valences of M″ plus y times the formal valence or valences of M′ is equal to z times the formal valence of the XD4, X2D7 or DXD4 group. In the compound, A is at least one of an alkali metal and hydrogen, M′ is a first-row transition metal, X is at least one of phosphorus, sulfur, arsenic, molybdenum, and tungsten, M″ any of a Group IIA, IIIA, IVA, VA, VIA, VIIA, VIIIA, IB, IIB, IIIB, IVB, VB, and VIB metal, D is at least one of oxygen, nitrogen, carbon, or a halogen, 0.0001<a≦0.1, and x, y, and z are greater than zero. The compound can have a conductivity at 27° C. of at least about 10−8 S / cm. The compound can be a doped lithium phosphate that can intercalate lithium or hydrogen. The compound can be used in an electrochemical device including electrodes and storage batteries and can have a gravimetric capacity of at least about 80 mAh / g while being charged / discharged at greater than about C rate of the compound.

The movement and mixing of microdroplets through microchannels is described employing microscale devices, comprising microdroplet transport channels, reaction regions, electrophoresis modules, and radiation detectors. Microdroplets are metered into defined volumes and are subsequently incorporated into a variety of biological assays. Electronic components are fabricated on the same substrate material, allowing sensors and controlling circuitry to be incorporated in the same device.

A continuous renal replacement therapy device adapted to be worn on a portion of the body of a patient, including: a plurality of contoured dialyzers, which are connected in series and utilize dialysate to remove impurities from the blood of the patient; and a plurality of contoured sorbent device, which are connected in series and are for regenerating the spent dialysate.

The invention relates to a microfabricated device for the rapid detection of DNA, proteins or other molecules associated with a particular disease. The devices and methods of the invention can be used for the simultaneous diagnosis of multiple diseases by detecting molecules (e.g. amounts of molecules), such as polynucleotides (e.g., DNA) or proteins (e.g., antibodies), by measuring the signal of a detectable reporter associated with hybridized polynucleotides or antigen / antibody complex. In the microfabricated device according to the invention, detection of the presence of molecules (i.e., polynucleotides, proteins, or antigen / antibody complexes) are correlated to a hybridization signal from an optically-detectable (e.g. fluorescent) reporter associated with the bound molecules. These hybridization signals can be detected by any suitable means, for example optical, and can be stored for example in a computer as a representation of the presence of a particular gene. Hybridization probes can be immobilized on a substrate that forms part of or is exposed to a channel or channels of the device that form a closed loop, for circulation of sample to actively contact complementary probes. Universal chips according to the invention can be fabricated not only with DNA but also with other molecules such as RNA, proteins, peptide nucleic acid (PNA) and polyamide molecules.

The present invention is directed to methods for removing carbon dioxide from air, which comprises exposing solvent covered surfaces to air streams where the airflow is kept laminar, or close to the laminar regime. The invention also provides for an apparatus, which is a laminar scrubber, comprising solvent covered surfaces situated such that they can be exposed to air stream. In another aspect, the invention provides a method and apparatus for separating carbon dioxide (CO2) bound in a solvent. The invention is particularly useful in processing hydroxide solvents containing CO2 captured from air.

A method, system and apparatus for performing peritoneal dialysis are provided. To this end, in part, a dialysis system is provided. The dialysis system includes a display device and a web browser and web server embedded in the dialysis system. The browser and the server operate with the display device to display a number of dialysis therapy set-up procedure screens that require operator input, and to display a number of dialysis treatment screens that graphically illustrate the progress of at least one step in the dialysis therapy in at least substantially real time.

Coatings applicable to a variety of substrate articles, structures, materials, and equipment are described. In various applications, the substrate includes metal surface susceptible to formation of oxide, nitride, fluoride, or chloride of such metal thereon, wherein the metal surface is configured to be contacted in use with gas, solid, or liquid that is reactive therewith to form a reaction product that is deleterious to the substrate article, structure, material, or equipment. The metal surface is coated with a protective coating preventing reaction of the coated surface with the reactive gas, and / or otherwise improving the electrical, chemical, thermal, or structural properties of the substrate article or equipment. Various methods of coating the metal surface are described, and for selecting the coating material that is utilized.

The present invention is a, solid block copolymer comprising at least two polymer end blocks A and at least one polymer interior block B wherein each A block is a polymer block resistant to sulfonation and each B block is a polymer block susceptible to sulfonation, and wherein said A and B blocks do not contain any significant levels of olefinic unsaturation. Preferably, each A block comprising one or more segments selected from polymerized (i) para-substituted styrene monomers, (ii) ethylene, (iii) alpha olefins of 3 to 18 carbon atoms; (iv) hydrogenated 1,3-cyclodiene monomers, (v) hydrogenated monomers of conjugated dienes having a vinyl content less than 35 mol percent prior to hydrogenation, (vi) acrylic esters, (vii) methacrylic esters, and (viii) mixtures thereof; and each B block comprising segments of one or more polymerized vinyl aromatic monomers selected from (i) unsubstituted styrene monomers, (ii) ortho-substituted styrene monomers, (iii) meta-substituted styrene monomers, (iv) alpha-methylstyrene, (v) 1,1-diphenylethylene, (vi) 1,2-diphenylethylene and (vii) mixtures thereof. Also claimed are processes for making such block copolymers, and the various end uses and applications for such block copolymers.

Systems and methods for the performance of kidney replacement therapy having or using a dialyzer, control components, sorbent cartridge and fluid reservoirs configured to be of a weight and size suitable to be worn or carried by an individual requiring treatment are disclosed. The system for performing kidney replacement therapy has a controlled compliance dialysis circuit, where a control pump controls the bi-directional movement of fluid across a dialysis membrane. The dialysis circuit and an extracorporeal circuit for circulating blood are in fluid communication through the dialysis membrane. The flux of fluid moving between the extracorporeal circuit and the dialysis circuit is modified by the rate at which the control pump is operating such that a rate of ultrafiltration and convective clearance can be controlled. The system provides for the monitoring of an inlet and outlet conductivity of the sorbent cartridge to provide a facility to quantify or monitor the removal of urea by the sorbent cartridge.