A base material for a membrane filter contains 90% by mass or more of aluminum oxide and 0.1% by mass or more and 10% by mass or less of titanium oxide. In a pore distribution curve measured by a mercury porosimeter, the base material has a first peak and a second peak which is higher than the first peak and is located at a pore size larger than that of the first peak, and the volume of pores with a pore size of 7 m or more is 0.02 cm.sup.3/g or more.

A hollow fiber membrane of the present invention is a hollow fiber membrane having an outer surface and an inner surface, wherein the inner surface has a zebra stripe pattern in which dense portions and porous portions are alternately formed in the longitudinal direction, and the outer surface has a maximum pore size of about 1 m or less (about 1 m), and wherein the hollow fiber membrane has a water permeability (flux) of about 1,300 LMH/bar to about 5,000 LMH/bar.

The porous hollow fiber membrane of the present invention contains a thermoplastic resin, and includes a surface having a surface porosity of 32 to 60% and a fine pore diameter of 300 nm or less, and has a compressive strength of 0.7 MPa or more. The porous hollow fiber membrane of the present invention may include at least two layers, and in this case, the surface of one layer has a thickness of backbone of 0.3 to 20 m and a fine pore diameter of 0.3 to 10 m, and the surface of the other layer has a surface porosity of 32 to 60% and a fine pore diameter of 0.05 to 0.3 m.

This invention describes a method and a device for efficient isolation of extracellular vesicles from animal and human biological fluids, as well as from culture fluid using equipment of standard diagnostic laboratories, that is, without the use of ultracentrifugation. These method and device can be applied for the diagnosis of various human diseases, as well as for therapeutic purposes, if the purified vesicles are used as an agent for drug delivery to the cells of the body. The device for the purification of extracellular vesicles contains at least two membrane filters: the first filter containing a membrane with pore sizes in the range from 400 to 600 nm, connected to the second filter containing a membrane with pores in the range from 95 to 200 nm. At the same time, the membranes of these filters are made of materials that practically do not bind biological polymers.

The porous hollow fiber membrane of the present invention contains a thermoplastic resin, and includes a surface having a surface porosity of 32 to 60% and a fine pore diameter of 300 nm or less, and has a compressive strength of 0.7 MPa or more. The porous hollow fiber membrane of the present invention may include at least two layers, and in this case, the surface of one layer has a thickness of backbone of 0.3 to 20 m and a fine pore diameter of 0.3 to 10 m, and the surface of the other layer has a surface porosity of 32 to 60% and a fine pore diameter of 0.05 to 0.3 m.

A method for producing a crystalline film comprising zeolite and/or zeolite-like crystals on a porous substrate is described. The method has the steps of: providing a porous support; modifying at least a surface of the top-layer of said porous support by treatment with a composition having one or more cationic polymer(s); rendering at least the outer surface of said porous support hydrophobic by treatment with a composition having one or more hydrophobic agent(s); subjecting said treated porous support to a composition having zeolite and/or zeolite-like crystals thereby depositing and attaching zeolite and/or zeolite-like crystals on said treated porous support, and growing a crystalline film of zeolite and/or zeolite-like crystals on said treated porous support and calcination. Crystalline films find use in a variety of fields such as in the production of membranes, catalysts etc.

The present invention is directed to nanofiltration (NF) composite membranes comprising at least one polymeric porous substrate layer (S) and at least one porous selfassembled supramolecular membrane layer (F); a method of preparing such composite membranes; method of separation/filtration/purification of heavy metal cations, inorganic anions, and organic small molecules by applying such composite membranes; as well as filter cartridges and filtration devices comprising said composite membranes.

A zeolite membrane structure includes a porous support, and a zeolite membrane. The zeolite membrane has a first zeolite layer located in a surface of the porous support, and a second zeolite layer located outside of the surface of the porous support and integrally formed with the first zeolite layer. The porous support has an outermost layer in which the first zeolite layer is located. An average thickness of the first zeolite layer is less than or equal to 5.4 micrometers. A porosity of the outermost layer is greater than or equal to 20% and less than or equal to 60%.

Compositions and methods are described for self-assembled polymer materials having at least one of macro, meso, or micro pores.

Methods of making blended, isoporous, asymmetric (graded) films (e.g. ultrafiltration membranes) comprising two or more chemically distinct block copolymers and blended, isoporous, asymmetric (graded) films (e.g. ultrafiltration membranes) comprising two or more chemically distinct block copolymers. The generation of blended membranes by mixing two chemically distinct block copolymers in the casting solution demonstrates a pathway to advanced asymmetric block copolymer derived films, which can be used as ultrafiltration membranes, in which different pore surface chemistries and associated functionalities can be integrated into a single membrane via standard membrane fabrication, i.e. without requiring laborious post-fabrication modification steps. The block copolymers may be diblock, triblock and/or multiblock mixes and some block copolymers in the mix may be functionally modified. Triblock copolymers comprising a reactive group (e.g., sulfhydryl group) terminated block and films comprising the triblock copolymers.