B01D2325/34

CROSS-LINKED ZWITTERIONIC POLYMER NETWORK AND THEIR USE IN MEMBRANE FILTERS

Disclosed are crosslinked copolymer network, comprising a copolymer, comprising a plurality of zwitterionic repeat units, and a plurality of a first type of hydrophobic repeat units; a plurality of crosslinking units; and a plurality of crosslinks; wherein each crosslinking unit comprises a first terminal thiol moiety and a second terminal thiol moiety; each hydrophobic repeat unit comprises an alkene; and each crosslink is formed from (i) the first terminal thiol moiety of a crosslinking unit and the alkene of a first hydrophobic repeat unit, and (i) the second terminal thiol moiety of the crosslinking unit and the alkene of a second hydrophobic repeat unit; and the method of making such cross-linked copolymer network. Also disclosed are the thin film composite membrane comprising the cross-linked copolymer network; and methods for using such thin film composite membrane.

METHOD FOR EXOSOME SEPARATION AND EXTRACTION BY STACKED CENTRIFUGAL FILTRATION
20190134565 · 2019-05-09 ·

A method for exosome separation and extraction by stacked centrifugal filtration. It is used in molecular biology and clinical examination and comprises an exosome separation and extraction kit consisting of the stacked centrifugal filtration device, incubation buffer and protease K. The sample to be tested is incubated at room temperature using the incubation buffer and an appropriate amount of protease K, followed by centrifugation with the stacked centrifugal filtration device. After mixing thoroughly, the retentate in the ultrafiltration tube is collected to obtain the exosomes. The method needs no ultracentrifugation equipment and allows quick acquisition of purified exosomes within 30 min. This method is suitable for clinical purification for exosome tests, featuring by its short operating time and the ability for parallel treatment of multiple samples, with reasonable cost.

Curable compositions and membranes

A membrane obtainable from curing a composition comprising: (i) a curable compound comprising at least two (meth)acrylic groups and a sulphonic acid group and having a molecular weight which satisfies the equation:
MW<(300+300n) wherein: MW is the molecular weight of the said curable compound; and n has a value of 1, 2, 3 or 4 and is the number of sulphonic acid groups present in the said curable compound; and optionally (ii) a curable compound having one ethylenically unsaturated group; wherein the molar fraction of curable compounds comprising at least two (meth)acrylic groups, relative to the total number of moles of curable compounds present in the composition, is at least 0.25.

Polyvinylidene Fluoride/Ultra-high Molecular Weight Polyethylene Blend Microporous Membrane and Preparation Method Thereof
20190105611 · 2019-04-11 ·

Disclosed is a polyvinylidene fluoride/ultra-high molecular weight polyethylene blend microporous membrane and preparation method thereof, which belongs to the field of microporous membrane. The blend microporous membrane has good hydrophobicity, mechanical properties and permeability. The preparation method includes: preparing a suspension by polyvinylidene fluoride, ultra-high molecular weight polyethylene, antioxidant and diluent; then feeding the obtained suspension into a twin-screw extruder, and the cast membrane gel extruded from the outlet is directly injected into a metal mold for injection molding; the mold temperature and the outlet temperature of the extruder are the same, and the cavity surface of the mold has micro-prism array structure; then cooling the mold in aqueous medium to obtain a nascent gel membrane; drying the obtained nascent gel membrane in a freeze dryer after removal of the diluents by extraction. The prepared membrane can be used in the membrane separation technology such as membrane distillation.

Porous asymmetric polyphenylene ether membranes and associated separation modules and methods

A porous asymmetric membrane comprises a hydrophobic polymer comprising a poly(phenylene ether) or poly(phenylene ether) copolymer; and a polymer additive. A separation module can be fabricated from the porous asymmetric membrane. A method of forming the porous asymmetric membrane comprises: dissolving a hydrophobic polymer comprising a poly(phenylene ether) or poly(phenylene ether) copolymer and, a polymer additive in a water-miscible polar aprotic solvent to form a porous asymmetric membrane-forming composition; and phase-inverting the porous asymmetric membrane forming-composition in a first non-solvent composition to form the porous asymmetric membrane. The polymer additive comprises hydrophilic functional groups, copolymerized hydrophilic monomers, or blocks of hydrophilic monomer repeat units. For example, the polymer additive can comprise a hydrophilic polymer or amphiphilic polymer. The porous asymmetric membrane can be a flat membrane or hollow fiber.

Porous asymmetric polyphenylene ether membranes and associated separation modules and methods

A porous asymmetric membrane comprises a hydrophobic polymer comprising a poly(phenylene ether) or poly(phenylene ether) copolymer; and a polymer additive. A separation module can be fabricated from the porous asymmetric membrane. A method of forming the porous asymmetric membrane comprises: dissolving a hydrophobic polymer comprising a poly(phenylene ether) or poly(phenylene ether) copolymer and, a polymer additive in a water-miscible polar aprotic solvent to form a porous asymmetric membrane-forming composition; and phase-inverting the porous asymmetric membrane forming-composition in a first non-solvent composition to form the porous asymmetric membrane. The polymer additive comprises hydrophilic functional groups, copolymerized hydrophilic monomers, or blocks of hydrophilic monomer repeat units. For example, the polymer additive can comprise a hydrophilic polymer or amphiphilic polymer. The porous asymmetric membrane can be a flat membrane or hollow fiber.

Microporous material and a method of making same

A method for producing a microporous material comprising the steps of: providing an ultrahigh molecular weight polyethylene (UHMWPE); providing a filler, providing a processing plasticizer, adding the filler to the UHMWPE in a mixture being in the range of from about 1:9 to about 15:1 filler to UHMWPE by weight; adding the processing plasticizer to the mixture; extruding the mixture to form a sheet from the mixture; calendering the sheet; extracting the processing plasticizer from the sheet to produce a matrix comprising UHMWPE and the filler distributed throughout the matrix; stretching the microporous material in at least one direction to a stretch ratio of at least about 1.5 to produce a stretched microporous matrix; and subsequently calendering the stretched microporous matrix to produce a microporous material which exhibits improved physical and dimensional stability properties over the stretched microporous matrix.

Membrane and device for treating hemolytic events

The present disclosure relates to a hemodialysis membrane for the treatment of hemolytic events, especially acute episodes of hemolysis which lead to elevated levels of plasma free hemoglobin. The present disclosure further relates to methods of removing hemoglobin from the blood of patients undergoing a hemolytic event. The treatment and method encompasses using a hemodialysis membrane which is characterized in that it comprises at least one hydrophobic polymer and at least one hydrophilic polymer and in that it has a MWRO of between 15 and 20 kD and a MWCO of between 170-320 kD, or, in the alternative, has a MWRO of between 9 and 14 kD and a MWCO of between 55 kD and 130 kD.

Gas separation membranes from polymer-grafted nanoparticles

Gas separation membranes as may be used in separating gaseous materials from one another and methods of forming the membranes are described. The separation membranes include polymer-grafted nanoparticles (GNPs) as a platform and a relatively small amount of free polymer. The free polymer and the polymer grafted to the nanoparticles have the same chemical structure and similar number average molecular weights. The gas separation membranes can exhibit high ideal selectivity and can be used in a variety of applications, such as carbon capture.

ISOLATION AND PURIFICATION METHOD OF EXTRACELLULAR VESICLES

[Object]

To provide an isolation and purification method for isolating and purifying extracellular vesicles.

[Solution]

An isolation and purification method of extracellular vesicles is disclosed. A hollow fiber membrane has an inner diameter of 0.2 mm to 1.4 mm and a molecular weight cut-off of 100000 to 1000000. Filtering includes a first filtration process of press-fitting the culture supernatant of the mesenchymal stem cells from a first opening on one end side of the hollow fiber membrane and filtering the culture supernatant to separate the culture supernatant into a permeate and a first concentrate, and a second filtration process of press-fitting the first concentrate from a second opening on the other end side of the hollow fiber membrane and filtering the first concentrate to separate the first concentrate into a permeate and a second concentrate. A concentrate is produced in which a concentration of the extracellular vesicles is increased by alternating tangential flow filtration in which the first filtration process and the second filtration process are alternately performed a plurality of times. A membrane surface velocity in the first filtration process and the second filtration process is 0.3 m/sec to 2 m/sec.