The invention relates to a filter unit (1, 19), having: at least one warp-knitted spacer (3) which comprises a first and a second cover layer (4; 5) having in each case a multiplicity of openings (6) which are delimited by peripheral regions (7), wherein threads (8) extend from the peripheral regions (7) of the first cover layer (4) to peripheral regions (7) of the second cover layer (5), and wherein the at least one warp-knitted spacer is rolled, twisted, and/or at least in one portion is compressed.

Virus and microbe-killing, self-sterilizing resistive heated air filters and methods of making and using same methods. The air filter is includes laser-induced graphene (LIG), a porous conductive graphene foam formed through photothermal conversion of a polyimide film (or another source or source of polymer or other LIG precursor material) by a laser source. The LIG in the air filter can capture particulates and bacteria. The bacteria cannot proliferate even when submerged in culture medium. Through a periodic Joule-heating mechanism, the filter easily reaches greater than 300° C. This destroys any microorganisms including bacteria, along with molecules that can cause adverse biological reactions and diseases such as viruses, pyrogens, allergens, exotoxins, endotoxins, teichoic acids, mycotoxins, nucleic acids, and prions

Intra-nasal filter devices and methods for their manufacture and use are disclosed. An intra-nasal filter device includes: a first stage filter proximate the septum; and a second stage filter comprising a flexible material extending upwardly from the first filter stage filter; wherein the flexible material comprises: an impedance in the range of 0.02 to 0.2 cmH.sub.2O; an effective cross-sectional area in the range of 0.2 to 2 square inches; and a plurality of radially extending geometric structures disposed along an axial length of the second stage.

Provided herein are sterilizable porous filtration media and methods of making and using the same.

A liquid containing exosomes is filtered through a first filter that has a hole diameter that passes the exosomes and blocks cells, and is then stored in a first storage unit (rough filtration step). Next, pressure is applied to the inside of the first storage unit to pump the liquid to a pre-filtration chamber in a second filter that blocks the exosomes so that water in the liquid is filtered out into a post-filtration chamber. The exosome-containing liquid that was not filtered out is returned to the first storage unit, thereby increasing the exosome concentration in the liquid for extraction (concentration step). The exosome-containing concentrate in the first storage unit is then filtered through a third filter having a hole diameter that passes the exosomes and blocks bacteria, and is sent to a recovery unit (sterilization filtration step).

Intra-nasal filter devices and methods for their manufacture and use are disclosed. An intra-nasal filter device includes: a first stage filter proximate the septum; and a second stage filter comprising a flexible material extending upwardly from the first filter stage filter; wherein the flexible material comprises: an impedance in the range of 0.02 to 0.2 cmH.sub.2O; an effective cross-sectional area in the range of 0.2 to 2 square inches; and a plurality of radially extending geometric structures disposed along an axial length of the second stage.

Virus and microbe-killing, self-sterilizing resistive heated air filters and methods of making and using same methods. The air filter is includes laser-induced graphene (LIG), a porous conductive graphene foam formed through photothermal conversion of a polyimide film (or another source or source of polymer or other LIG precursor material) by a laser source. The LIG in the air filter can capture particulates and bacteria. The bacteria cannot proliferate even when submerged in culture medium. Through a periodic Joule-heating mechanism, the filter easily reaches greater than 300? C. This destroys any microorganisms including bacteria, along with molecules that can cause adverse biological reactions and diseases such as viruses, pyrogens, allergens, exotoxins, endotoxins, teichoic acids, mycotoxins, nucleic acids, and prions.

A composite filter aid may include at least one mineral associated with an antimicrobial metal compound, wherein the filter aid has a permeability ranging from 0.1 to 20 darcys. The antimicrobial metal compound can be chemically deposited on the mineral surface or bonded to mineral structure by binder or high temperature calcination.

The invention relates to a filter unit (1, 19), having: at least one warp-knitted spacer (3) which comprises a first and a second cover layer (4; 5) having in each case a multiplicity of openings (6) which are delimited by peripheral regions (7), wherein threads (8) extend from the peripheral regions (7) of the first cover layer (4) to peripheral regions (7) of the second cover layer (5), and wherein the at least one warp-knitted spacer is rolled, twisted, and/or at least in one portion is compressed.

A liquid containing exosomes is filtered through a first filter that has a hole diameter that passes the exosomes and blocks cells, and is then stored in a first storage unit (rough filtration step). Next, pressure is applied to the inside of the first storage unit to pump the liquid to a pre-filtration chamber in a second filter that blocks the exosomes so that water in the liquid is filtered out into a post-filtration chamber. The exosome-containing liquid that was not filtered out is returned to the first storage unit, thereby increasing the exosome concentration in the liquid for extraction (concentration step). The exosome-containing concentrate in the first storage unit is then filtered through a third filter having a hole diameter that passes the exosomes and blocks bacteria, and is sent to a recovery unit (sterilization filtration step).