781 results about "Semipermeable membranes" patented technology

Disclosed are esophageal anti-reflux valve prostheses, and tools and procedures for peroral implantation and extraction of the prostheses. The prostheses disclosed have a semipermeable membrane to allow retrograde passage of gas, magnets disposed at a distal end of the sleeve to facilitate closure, and an outwardly bendable array of spikes that are longitudinally aligned for peroral insertion and lockable into a radially outwardly deployed configuration to keep the prosthesis from dislocating after implantation. The implantation tool has inner and outer concentric tubes, the inner tube releasably threadably connected to the prosthesis, the outer tube reverse threaded with the inner tube to advance a distal headpiece to engage, deploy and lock the spikes into the deployed configuration. A vacuum assist can be used to help impact the lumen wall on the spikes. The extraction tool is similar to the implantation tool with an inner tube for threadably engaging the prosthesis, an outer tube with a distal crown with a plurality of shoes to unseat and unlock the spikes, and an overtube shield to receive the spikes and facilitate extraction of the prosthesis.

A blood purification device has a blood purification element divided into two chambers by a semipermeable membrane, with a first chamber as part of a dialysis fluid loop and a second chamber as part of an extracorporeal blood loop. By virtue of an analysis unit operatively connected to a sensor in the dialysis fluid loop, the device provides simple and uncomplicated determination of the blood purification performance of the blood purification element for a second material by derivation from a previously established blood purification performance for a first material. In this way, the device also determines the blood concentration of the second material during the blood treatment through measurements in the dialysis fluid without intervention in the treatment sequence.

When forming a separating functional layer containing crosslinked polyamide, by carrying this out in the presence of 1) carboxylic acid ester with a total of 8 or more carbons, or 2) carboxylic acid, it is possible to provide a composite semipermeable membrane which, while still maintaining a high rejection rate, is more outstanding in its water permeability than hitherto.

The present invention relates to semipermeable membranes with nanotubes dispersed therein, and the methods of preparing the same.

In a hemodiafiltration apparatus, a membrane device (2) comprises a blood chamber (3) and a fluid chamber (4) separated by a semipermeable membrane (5). A grounding device (17) is connected to the discharge line by means of a tubular connector (16) made of an electrically-conductive plastic material. The grounding device can disconnect the grounding connection if the leakage current measured on a patient (1) connected to the apparatus exceeds a predetermined value. The apparatus can be classified as Cardiac Floating and, at the same time, causes no disturbances to an electrocardiograph connected to the patient.

Systems and methods for controlling fluid movement and volumes of fluid between a subject and a controlled compliant flow path. The controlled compliant flow path has a means for selectively metering in and metering out fluid from the controlled compliant flow path. An extracorporeal flow path is in fluid communication with the controlled compliant flow path across a semi-permeable membrane where the extracorporeal flow path has a first terminal end and a second terminal end.

A composite semipermeable membrane comprising a porous support membrane on which a separating functional polyamide layer resulting from the polycondensation reaction of polyfunctional aromatic amines with polyfunctional acid halides is formed, wherein the separating functional polyamide layer has carboxy groups, amino groups, phenolic hydroxyl groups, and azo groups, wherein XA, the ratio of the amino groups (molar equivalent of the amino groups / (molar equivalent of the azo groups+molar equivalent of the phenolic hydroxyl groups+molar equivalent of the amino groups)) on a feed water contact surface of the separating functional polyamide layer (an A surface), is in the range 0.5 or less, and XB, the ratio of the amino groups (molar equivalent of the amino groups / (molar equivalent of the azo groups+molar equivalent of the phenolic hydroxyl groups+molar equivalent of the amino groups)) on a permeate-side surface of the separating functional polyamide layer (a B surface), i.e., the opposite side to the A surface, is in the range of 0.5 to 1. The present invention provides a composite semipermeable membrane that achieves a balance between high solute removal properties and a high permeate flow rate and has high organic-solvent resistance, and a method for producing same.

A composite semipermeable membrane which satisfies the following relationship when seawater at 25° C. having a pH of 6.5, a boron concentration of 5 ppm and a TDS concentration of 3.5% by weight is permeated under an operation pressure of 5.5 MPa: Boron removal ratio (%)≧95−4×membrane permeation flow rate (m3 / m2·day).

The present invention provides a simple and improved rupturing controlled release device that is capable of providing a controlled release of active agent contained in the core first through a preformed passageway and then through an in situ formed second passageway into an environment of use in a standardized release profile manner. The rupturing controlled release device comprises a core comprising at least one drug and at least one osmopolymer, a semipermeable membrane enclosing the core and having at least one preformed passageway there through, wherein the semipermeable membrane ruptures during use to form a second passageway in the semipermeable membrane at a location spaced away from the preformed passageway, and a release-controlling subcoat between the core and the semipermeable membrane.

A system which includes a separation element (11) employing semipermeable membrane material (17), which system is designed so that it can operate either in an RO mode to produce high quality water or in a PRO mode to generate power from two aqueous solutions of different salt concentrations. In a preferred embodiment, a rotary pressure transfer device (29) is included to transfer pressure from an outlet stream exiting the separation element to an inlet stream being supplied to the separation element.

The invention provides a process for producing a tubular membrane assembly comprising helically winding at least one strip of fibrous material on a mandrel to produce at least a single ply tubular support member for a semi-permeable membrane, characterized by passing the strip through a heated section of the mandrel during the helical winding thereof to flatten and smooth fibers protruding along the cross-sectional width of the strip, whereby a tube with a smooth inner bore along its entire length is formed.

Laser-induced phase-separation polymerization of a porous acrylate polymer is used for in-situ fabrication of dialysis membranes inside glass microchannels. A shaped 355 nm laser beam is used to produce a porous polymer membrane with a thickness of about 15 μm, which bonds to the glass microchannel and form a semi-permeable membrane. Differential permeation through a membrane formed with pentaerythritol triacrylate was observed and quantified by comparing the response of the membrane to fluorescein and fluorescently tagging 200 nm latex microspheres. Differential permeation was observed and quantified by comparing the response to rhodamine 560 and lactalbumin protein in a membrane formed with SPE-methylene bisacrylamide. The porous membranes illustrate the capability for the present technique to integrate sample cleanup into chip-based analysis systems.

The invention relates to a blood treatment device by extracorporeal circulation comprising a filter having a primary chamber and a secondary chamber separated by a semi-permeable membrane; a blood circuit comprising an arterial line intended to come from the patient, the filter's primary chamber and the venous line intended to return to the patient; a dialysate circuit comprising the filter's secondary chamber and at least a drain line for circulating the waste intended to come from the filter and intended to go to a drain; a first bag in fluid communication with the drain line; at least a first gravimetric weighing means linked to the first bag, fluid flow rate adjustment means acting on the drain line; a control unit linked to the first gravimetric weighing means and with the fluid flow rate adjustment means; a second bag in fluid communication with the drain line, the control unit being capable of receiving weight signals from the first gravimetric weighing means and of controlling the fluid flow rate adjustment means to load one of the bags with liquid while the other bag unloads liquid, and vice-versa. The invention also relates to a single-use drain line for use in a treatment device according to the invention.

A sensing device having a first and second opening, a first semipermeable membrane having a first surface and a second surface, and a second semipermeable membrane having a third and fourth surface, a ketone body sensor, and a void. The first opening is juxtaposed to the first surface and the second opening is juxtaposed to the third surface. The space between the first and second openings is the void and wherein the ketone body sensor is positioned within the void. Gasses may permeate through the first opening and into the void to contact the sensor and exit the void through the second opening.

A polyamide membrane comprising reaction product of an anhydrous solution comprising an anhydrous solvent, at least one polyfunctional secondary amine and a pre-polymer deposition catalyst; and an anhydrous, organic solvent solution comprising a polyfunctional aromatic amine-reactive reactant comprising one ring. A composite semipermeable membrane comprising the polyamide membrane on a porous support. A method of making a composite semipermeable membrane by coating a porous support with an anhydrous solution comprising an anhydrous solvent, a polyfunctional secondary amine and a pre-polymer deposition catalyst, to form an activated pre-polymer layer on the porous support and contacting the activated pre-polymer layer with an anhydrous, organic solvent solution comprising a polyfunctional amine-reactive reactant to interfacially condense the amine-reactive reactant with the polyfunctional secondary amine, thereby forming a cross-linked, interfacial polyamide layer on the porous support. A method of impregnating a composite semipermeable membrane with nanoparticles selected from heavy metals and / or oxides of heavy metals.

The present invention concerns improved methods and compositions for producing a Neublastin polypeptide as well as local delivery of Neublastin to specific regions of the nervous system including the central nervous system and the eye for example by gene therapy. The invention also concerns Neublastin expression constructs which do not encode a pro-region of a Neublastin polypeptide, which expression construct result in increased secretion of bioactive Neublastin. The invention includes the delivery of Neublastin from transduced or transfected cells encapsulated into a macrocapsule with a semipermeable membrane. The invention further concerns mammalian cells capable of producing Neublastin in increased amounts.

A system which includes a separation element (11) employing semipermeable membrane material (17), which system is designed so that it can operate either in an RO mode to produce high quality water or in a PRO mode to generate power from two aqueous solutions of different salt concentrations. In a preferred embodiment, a rotary pressure transfer device (29) is included to transfer pressure from an outlet stream exiting the separation element to an inlet stream being supplied to the separation element.

Disclosed are esophageal anti-reflux valve prostheses, and tools and procedures for peroral implantation and extraction of the prostheses. The prostheses disclosed have a semipermeable membrane to allow retrograde passage of gas, magnets disposed at a distal end of the sleeve to facilitate closure, and an outwardly bendable array of spikes that are longitudinally aligned for peroral insertion and lockable into a radially outwardly deployed configuration to keep the prosthesis from dislocating implantation. The implantation tool has inner and outer concentric tubes, the inner tube releasably threadably connected to the prosthesis, the outer tube reverse threaded with the inner tube to advance a distal headpiece to engage, deploy and lock the spikes into the deployed configuration. A vacuum assist can be used to help impact the lumen wall on the spikes. The extraction tool is similar to the implantation tool with an inner tube for threadably engaging the prosthesis, an outer tube with a distal crown with a plurality of shoes to unseat and unlock the spikes, and an overtube shield to receive the spikes and facilitate extraction of the prosthesis.

A metabolite monitoring system comprising a microdialysis probe including a semi-permeable membrane and a probe flow path passing from an inlet through a sensing volume adjacent to said semi-permeable membrane to an outlet, a fluid delivery device for delivering dialysate to said inlet; and a metabolite monitoring system associated with said outlet for monitoring a concentration of at least one metabolite in said dialysate from said microdialysis probe, wherein said fluid delivery device is configured to deliver a pulsed flow of said dialysate to said inlet.

A controlled release antihyperglycemic tablet that does not contain an expanding polymer and comprising a core containing the antihyperglycemic drug, a semipermeable membrane coating the core and at least one passageway in the membrane.

The present invention aims at providing a composite semipermeable membrane having outstanding water permeability and salt-blocking rate, and extremely small amount of unreacted polyfunctional amine components in the porous support, and at providing a process for producing the composite semipermeable membrane. A composite semipermeable membrane having a skin layer formed on the surface of a porous support, the skin layer comprising a polyamide resin obtained by interfacial polymerization of a polyfunctional amine component and a polyfunctional acid halide component, wherein the porous support has a microporous layer on a base material, and the content of an unreacted polyfunctional amine component in the base material after a membrane washing treatment is 0.5 mg / m2 or less.

There is provided a composite semipermeable membrane that shows a high salt removal ratio and high performance in rejecting boron that is not dissociated in the neutral region. The composite semipermeable membrane is produced by a process that includes forming a separating functional polyamide layer on a porous substrate film, while using an organic solvent solution containing a specific cyclic aliphatic compound or a specific aromatic compound such that a polyamide molecule that forms the separating functional polyamide layer has a partial structure composed of “a cyclic aliphatic group or an aromatic group having at least two specific substituents, at least one of which contains a heteroatom bond and a carbonyl group at the β or γ position”.

A method for producing a wet-laid nonwoven fabric for a semipermeable membrane supporting body, the method comprising: performing papermaking according to a wet papermaking method by using a fiber slurry containing a synthetic fiber as a main constituent fiber; drying the fiber slurry; subsequently subjecting the dried sheet to hot press processing two times by using a heat calender apparatus, wherein the hot press process temperature in the second treatments is adjusted to be higher by 10° C. or more than the hot press processing temperature in the first treatment, while treating the dried sheet by using a hard nip heat calender apparatus equipped with a combination of a metal roll and a metal roll for at least one time of the hot press processing; and thereby obtaining a wet-laid nonwoven fabric for a semipermeable membrane supporting body.