Abstract: Provided are a fiber rod, a blood collection instrument, and a blood test kit, which are capable of easily taking out a blood specimen. A fiber rod which is used in a blood collection instrument in a blood test kit, including a fiber portion which is composed of a first fiber and a second fiber having different fiber diameters and which has a void volume within a range of 90% to 97%, in which a distance between surfaces facing each other of the fiber portion includes a region within a range of 1 mm to 1.6 mm.

Abstract: A microencapsulated delivery system, composition or method is disclosed in which one or more agents to be delivered are encapsulated in small capsules (e.g., microcapsules), and the capsules are applied or adhered to one or more surfaces of a substrate. The encapsulated agent is latently released upon exposure to appropriate conditions.

Abstract: A filter assembly for use in an electronics enclosure is disclosed herein. The filter assembly has an inner assembly having a filter material comprising fibrous media and a containment assembly having a first containment layer and a second containment layer. The containment assembly defines an outer perimeter and the first containment layer and a second containment layer are bonded along the outer perimeter in an outer weld area to encapsulate the inner assembly. The outer weld area extends between the outer perimeter and an interior perimeter. The inner assembly defines an inner assembly perimeter that is within the outer perimeter of the containment assembly.

Abstract: Disclosed herein are nanofiber structures, and methods of making and using the same. In some embodiments, provided is a porous sheet comprising a plurality of nanofibers in contact with a supporting structure comprising a plurality of supporting elements, wherein: the nanofibers have an average diameter of about 10-900 nm; the supporting elements have an average thickness less than, about equal to, or greater than that of the thickness of the nanofibers; the sheet has an average thickness that is about 75%-150% of an average thickness of the supporting elements; a total volume of the nanofibers is less than about 20% of a total volume of the porous sheet; and/or a total volume of the supporting structure is less than about 50% of the total volume of the porous sheet. In some embodiments, provided is a multilayer structure comprising one or more sections, where each section independently comprises one or more porous sheets as described herein.

Abstract: Provided is a therapeutic device that includes tubing; at least one pump; and a column or filter capable of removing leukocytes, cytokines, and/or other blood components from the blood of a patient to effectively treat or prevent post-resuscitation syndrome. Methods for treating and/or preventing post-resuscitation syndrome that include the use of such a device, or a filter or column capable of selectively removing inflammatory biomarkers, are also provided.

Abstract: The latex polymer compositions of the present invention exhibit latent crosslinking properties. Latent crosslinking in the polymers takes advantage of the fast interaction between the anionic latex charge and the cationic charge associated with polyfunctional amine crosslinkers. Once the latex is coated onto a substrate, the volatile base evaporates and the groups react to form a crosslinked coating with improved wash-off properties.

Abstract: A filtering element for filtering devices, comprising a filtering material (5) which defines a filtering space and is intended for the filtration of fluids, and at least one water indicator (13, 19, 23) which is provided at a location coming into contact with fluid during the filtration mode and indicates the presence of water in the fluid in a visually recognizable manner, is characterized in that the at least one water indicator (13, 19, 23) is provided on an end cap (7, 9) for mounting at one end of the filtering material (5), and/or is at least partially part of the end cap (7, 9), and/or is provided on a fluid-permeable supporting structure (21) surrounding the filtering material (5), and/or is at least partially part of the supporting structure (21).

Abstract: A method of bonding a nanofiber web of nanofibers having diameters of between about 50 nanometers and about 2,000 nanometers onto a surface of a woven or nonwoven polymeric media having media fiber diameters of between about 700 nanometers and about 50,000 nanometers utilizes exposing the topmost layer of nanofibers and media fibers to a jet of heated air for a time and at a distance such that substantially only the topmost layer of fibers are bonded. The jet of heated air exits through a nozzle slot having a length of less than about 2 inches in the nanofiber web travel direction. The temperature of the heated air ranges from about 2 to about 10 times the nanofiber melting temperature, and heat air has a nozzle slot velocity of greater than about 500 feet/minute. An adhesive may bond the nanofibers, to a media, which may be bi-component fiber fibers.

Abstract: A polymer nanofiber structural body of the present invention is a polymer nanofiber structural body in which polymer nanofibers are integrated, including a first layer and a second layer different from each other in polymer nanofiber existence ratio, in which: both the first layer and the second layer are laminated through a buffer region; the buffer region includes a region in direct contact with both the first layer and the second layer; and a polymer nanofiber existence ratio of the region continuously changes from a polymer nanofiber existence ratio of the first layer to a polymer nanofiber existence ratio of the second layer in a direction from the first layer to the second layer.

Abstract: Flexible housing filters for filtration of fluids and methods of making such filters are disclosed. The filters may include one or more peripheral seals in the flexible housing.

Abstract: A system for disinfecting a fluid containing contaminants (chemical and biological) includes a plurality of photocatalytic particles secured to a substrate which contacts the fluid to be disinfected. An agitator for imparting translation and/or vibrational movement is in operational communication with the substrate to increase the contact of photocatalytic particles with contaminants in the fluid. The system can include a source of photons having a wavelength corresponding to band gap energy of the photocatalytic particles to illuminate the substrate. Although the invention can be used to disinfect air in air supply registers of a heating, ventilating and air conditioning system, or in air ducts, the disinfection of any fluid (including water) is contemplated.

Abstract: Various high performance, high efficiency filter media are provided that are cost effective and easy to manufacture. In particular, various filter media are provided having at least one layer with a waved configuration that results in an increased surface area, thereby enhancing various properties of the filter media. The filter media can be used to form a variety of filter elements for use in various applications.

Abstract: A fluid conduit with layered and partial covering material thereon is disclosed. The fluid conduit may be used for processing and treatment of fluids which must be treated to remove materials so that the resultant treated fluid may be reused and/or returned to the earth and particularly to the water table. The fluid conduit may be of many forms and types and may have attached thereto and configured thereon covering material in partial form and a selected number of layers. The fluid conduit may be a septic pipe of smooth wall, of corrugated form, and/or of any form of cross-sectional configuration including circular, elliptical, rectangular, triangular, or any other geometric shape. The fluid conduit may be used in combination with conduit in a drainage field or leaching system usually associated with a septic tank or septic system.

Abstract: The latex polymer compositions of the present invention exhibit latent crosslinking properties. Latent crosslinking in the polymers takes advantage of the fast interaction between the anionic latex charge and the cationic charge associated with polyfunctional amine crosslinkers. Once the latex is coated onto a substrate, the volatile base evaporates and the groups react to form a crosslinked coating with improved wash-off properties.

Abstract: Provided is a method of fabricating a filter medium including the following steps. An assembly of first fiber is formed by a first spinning device. A plurality of second fiber is formed by a second spinning device. On a reception device is collected a film having a three-dimensional non-woven structure constructed by the first fibers and the second fibers. Each of the first fibers has a diameter of 1-50 ?m. Each of the second fibers has a diameter of 1-1000 nm. The second spinning device is positioned between the first spinning device and the reception device. The first fibers and the second fibers stack with each other in a random manner to form the three-dimensional non-woven structure.

Abstract: A multi-layer, fluid transmissive structure is provided that comprises first and second fiber layers each comprising a plurality of polymeric fibers bonded to each other at spaced apart contact points. The polymeric fibers of these fiber layers have diameters greater than one micron and collectively define interconnected interstitial spaces providing tortuous fluid flow paths through the first and second fiber layers. The structure also comprises a plurality of nanofibers disposed intermediate at least a portion of the first fiber layer and at least a portion of the second fiber layer.

Abstract: A tubular depth filter element has three or more concentric zones. Each zone is made of an essentially continuous melt blown filament. The filament of an outer zone preferably has a larger diameter than the filaments of other zones. The outer zone overlaps with at least 85%, and preferably all, of another zone. Optionally, one or more additional filaments may traverse through all of zones. The depth filter element is made by spraying filaments onto a rotating mandrel to form a filament mass in contact with a conical press roller. The filaments are sprayed from three or more nozzles which are spaced apart along the length of the mandrel. One of the filaments is formed in a spray pattern that is angled towards an adjacent spray pattern so as to overlap with at least 50 or 85%, and preferably all, of the adjacent spray pattern.

Abstract: A fiber that has a unique surface topography in that it contains a plurality of nanohairs extending outwardly from an external surface of an elongate structure of the fiber is provided. To form the nanohairs, a polymer composition is spun that includes organofunctional nanoparticles (e.g., polyhedral organofunctional silsesquioxanes) embedded within a matrix of a base polymer. Despite being initially embedded within the polymer, the present inventors have discovered that, through selective control over the nature and relative concentration of the components of the composition, as well as the method in which the fiber is formed, a substantial portion of the nanoparticles can migrate to the surface of the fiber as it is formed and thus become arranged in the form of nanohairs.

Abstract: A gravity filter media fabricated from multiple spiral wound or pleated layers, where different layers are designed for specific contaminant removal process and the layers are combined into a single pack for ease of use. The layers or fiber sheets are chemically treated for contaminant removal, with different layers having different chemical treatments, or the layers are immobilized with particles of various sizes for use as low contact-time adsorbents, with different layers having different immobilized particles, or the pore structure is varied from one fiber sheet to another—one being a tight pore structure, and the other being a more open pore structure, or any combination thereof. When using immobilized particles, the immobilized particles can be chemically treated for the specific removal of targeted contaminants, and multi-layered for custom designed removal of specific contaminants.

Abstract: An aggregate-removing filter material efficiently removes aggregates that are contained in a blood product for transfusion and may cause transfusion reactions without clogging, and exhibits excellent quality stability, and a blood product filtration method uses a filter apparatus that includes the aggregate-removing filter material and a leukocyte-removing filter material. The aggregate-removing filter material includes short fibers having a fineness of 0.7 to 4.0 dtex and a fiber length of 1 to 80 mm, and a ground fabric that includes long fibers, a fiber axis of the long fibers being oriented in a planar direction of the ground fabric, the short fibers being entangled with the ground fabric so that the aggregate-removing filter material has a total weight per unit area of 10 to 80 g/m2, and a layer of the short fibers forming a three-dimensional structure.

Abstract: The invention provides a method of preparing a filter medium by thermally bonding silver-coated spunbonded nonwoven fabrics to a dirt-retaining membrane, a chemical-retaining membrane, a pathogen-retaining membrane, or a combination thereof. The invention also relates to the use of one or more silver-coated spunbonded nonwoven fabric layers as a component of a microorganism-killing membrane in filter media for a fluid filtration system. The filter media of the invention offers efficient disinfection effects, maintaining a low pressure drop and a high flow rate when in use. Further, the filter media is adhesive free and contains at least one thermal binding layer made of spunbonded nonwoven polymeric fabrics. The invention also features a water-purification cartridge and the use thereof in a potable water system.

Abstract: A leukocyte-removing filter, characterized in that it comprises a filter material having a vertical permeation coefficient (kx) of 0.5×10?12 to 2.0×10?12 m2 and a ratio (ky/kx) of a horizontal permeation coefficient (ky) to kx of 0.5 to 1.5; and a method for removing leukocytes using said filter. The above leukocyte-removing filter has a higher leukocyte-removing performance per unit volume and also does not bring clogging nor increase of pressure drop.

Abstract: The invention provides a novel method of preparing a filter media by thermally bonding silver-coated nanofiber fabrics to a dirt-retaining membrane, a chemical-retaining membrane, a pathogen-retaining membrane, or a combination thereof. The invention also relates to the use of silver-coated nanofiber fabric layer as a component of a microorganism-killing membrane in filter media for a liquid or air filtration system. The filter media of the invention offers efficient disinfection effects, maintaining a low pressure drop and a high flow rate when in use. Further, the filter media is adhesive-layer free and contains at least one thermal binding layer made of spunbonded nonwoven polymeric fabrics. The invention also features a water-purification cartridge and a portable water system thereof.

Abstract: The invention provides a novel type of filter media that offers efficient disinfection effects, while achieving a low water pressure drop and a high water flow rate when in use. Specifically, the filter media of the invention comprises a microorganism-killing membrane containing electro spun nanofiber fabrics loaded with biocidal nano-particles. The filter media of the invention is adhesive-layer free and contains at least one thermal binding layer that are made of spunbonded nonwoven polymeric fabrics. The invention also provides a water-purification cartridge and a portable water system thereof.

Abstract: A system for cleaning up an oil spill and recovering the spilled oil includes frames supporting superhydrophobic oil-absorbing nanowires. A first container supports the frames with the nanowires. A mixture of oil and water is pumped into the first container where the oil from the mixture is absorbed by the nanowires as water is separated from the mixture and deposited in the first container where it is then pumped therefrom. A second container supports the frames with the oil so-absorbed by the nanowires. The frames with the oil so-absorbed by the nanowires are heated whereby the oil so-absorbed separates from the nanowires and is deposited in the second container. The oil so-deposited in the second container is then pumped therefrom.

Abstract: A coalescence media for separation of water-hydrocarbon emulsions comprises an emulsion-contacting sheet formed of: (a) at least one component of the group consisting of natural fibers, cellulose fibers, natural-based fibers, and cellulose-based fibers, at least one component of the group consisting of high-surface-area fibrillated fibers, surface-area-enhancing synthetic material, glass microfibers, and nanoceramic functionalized fibers; and (c) at least one component of the group consisting of a dry strength additive, and a wet strength additive, wherein the fibrous components of the media constitute at least about 70% of the media. In preferred embodiments, the coalescence media comprises kraft fibers, fibrillated lyocell fibers, glass microfibers or nanoceramic functionalized fibers, a wet strength additive, and a dry strength additive. Preferably, the coalescence media is formed as a single, self-supporting layer from a wet-laid process using a homogenously distributed, wet-laid furnish.

Abstract: Fiber webs which are used in filter media are described herein. In some embodiments, the fiber webs include fibrillated fibers and optionally non-fibrillated fibers, amongst other optional components (e.g., binder resin). In some embodiments, the fiber webs include limited amounts of, or no, glass fiber. The respective characteristics and amounts of the fibrillated fibers are selected to impart desirable properties including mechanical properties and filtration properties (e.g., dust holding capacity and efficiency), amongst other benefits.

Abstract: The invention relates to a multi-layer cleanable filter material for gas and liquid filtration, said filter material comprising a filter layer and a substrate layer that follows the filter layer in the flow direction, wherein the filter layer is substantially dendrite-free and consists of a melt-blown fleece made of elastic polymer fibres that has a breaking elongation of at least 100%.

Abstract: The present invention relates to a filter medium, a method for the manufacture thereof and the use of the filter medium according to the invention. The filter medium according to the invention comprises at least two textile nonwoven layers which are joined to one another by needling. The needled composite is then subjected to an aftertreatment so that the holes present from he needling are reduced by at least 50%.

Abstract: The above objective are accomplished by providing a filter medium for use in manufacturing of hydraulic fluid and air filters comprising: an upstream layer comprised of nonwoven fiber having a denier between about 5.0 and 7.0 and a weight of between about 3.0 and 5.0 ounces a scrim and a cap layer comprising a fiber having a denier between about 0.1 and 5.0 denier and a weight between about 2.0 and 4.0 ounces carried by said upstream layer and disposed downstream from said upstream layer. The upstream layer, scrim and cap layer can have a weight of about 4.0 ounces, 2.0 ounces and 3.0 ounces respectively. A downstream layer can be disposed between said upstream layer and said cap layer.

Abstract: The present invention provides a filtering material for filtering water having high collection efficiency and long filtering life, and a water filtering apparatus including the material. The present filtering material includes a laminated sheet in which a nanofiber layer formed from a nanofiber having a single fiber average diameter of 10 to 1000 nm and meeting all the following conditions and a base material including a nonwoven or woven fabric containing a hydrophilic fiber having a single fiber average diameter of not less than 1 ?m. Further, the present water filtering apparatus is configured by including the filtering material for filtering water. (1) The nanofiber layer has a basis weight of 0.1 to 10 g/m2. (2) The nanofiber is a continuous long fiber. (3) The nanofiber contains at least an ethylene-vinyl alcohol copolymer.

Abstract: The present invention provides an absorbent which can remove cells present in blood including activated leukocytes such as granulocytes and monocytes, and cancer cells as well as can remove cytokines which facilitate the activation of the remaining cells, and further has no concern for pressure loss and has high configuration stability. That is, the present invention provides an absorbent which absorbs the granulocytes and the monocytes in blood, an absorbent for cancer therapy which absorbs an immunosuppressive protein and an absorbent having a bilayer structure of a net and a nonwoven fabric, having a zeta potential of ?20 mV or more, as well as a blood circulation column containing any of the absorbents filled therein.

Abstract: A filter pad comprising a pad of non-woven fibrous material having a peripheral region in which opposing faces have been compressed together and fused so as to form an outwardly-extending peripheral lip.

Abstract: A reusable multi-functional pad/filtration device for providing an easy and unique way to absorb fluids from raw, thawed, or cooked foods. The device features two outer layers that sandwich two middle layers and an absorbent gasket. The gasket is positioned between the two middle layers. Borders are disposed on each side edge of the device. The device may be used in combination with a holding system that includes a base and a serving tray.

Abstract: Separation media, separation modules and methods are provided for separating water from a water and hydrocarbon emulsion and include a fibrous nonwoven coalescence layer for receiving the water and hydrocarbon emulsion and coalescing the water present therein as a discontinuous phase to achieve coalesced water droplets having a size of 1 mm or greater, and a fibrous nonwoven drop retention layer downstream of the coalescence layer having a high BET surface area of at least 90 m2/g or greater sufficient to retain the size of the coalesced water droplets to allow separation thereof from the hydrocarbon.

Abstract: Fluid filtration articles, including composite nonwoven fibrous webs, and methods of making and using such articles as gas or liquid filtration elements. The articles include a population of coarse microfibers having a population median diameter of at least 1 micrometer (?m) formed as a first layer, and a population of fine fibers having a population median diameter less than 10 ?m formed as a second layer adjoining the first layer. At least one of the fiber populations may be oriented. In one implementation, the coarse microfibers and fine fibers are polymeric, the coarse microfibers have a population median diameter of at least 10 ?m, and the fine fibers have a population median diameter less than 10 ?m. In another implementation, the population of fine fibers has a population median diameter less than 1 ?m. Optionally, one or both of the first and second layers may include particulates.

Abstract: A method of removing leukocytes that through reducing of clogging of a leukocyte removing filter element by blood cell components and plasma proteins being a problem encountered at the time of removing leukocytes from blood, shortens the filtration time at refrigerated filtration and exhibits high leukocyte removing performance at room temperature filtration. There is provided a method of removing leukocytes including filtering blood containing leukocytes through a leukocyte removing filter apparatus having multiple fibrous filter elements with different average fiber diameters to thereby remove leukocytes from the blood, characterized in that use is made of a leukocyte removing filter apparatus wherein the multiple fibrous filter elements include at least leukocyte removing filter element (A) of 2.0 to <4.0 ?m average fiber diameter and leukocyte removing filter element (B) of 0.7 to 1.

Abstract: The present invention relates to a filter composed of a multi-ply filter medium which (i) has at least one textile stiffening layer (layer 4), preferably a non-woven layer, of synthetic, polymer fibers, glass fibers or mixtures of the same, (ii) at least one filtration layer (layer 3), which is attached to at least one side of the non-woven stiffening fabric, the filtration layer being made up of glass fibers, (iii) at least one further filtration layer (layer 2), which is applied on the filtration layer according to ii), the further filtration layer being made up of glass fibers, and at least one textile cover layer (layer 1), which is applied on the filtration layer according to (iii), the cover layer being made up of synthetic polymer fibers.

Abstract: A support for a separation membrane includes a long-fiber nonwoven fabric composed of thermoplastic continuous filaments.

Abstract: Disclosed are coalescing media for coalescing a mixture of two phases, namely a continuous phase and a dispersed phase. The disclosed coalescing media has multiple layers with distinct porosities, where an interior layer of the coalescing media has a higher porosity than the layers immediately adjacent to the interior layer. The disclosed media may be utilized in coalescers, coalescing systems, or coalescing methods for removing the dispersed phase from the mixture.

Abstract: Fine fiber products including fiber webs, as well as related assemblies, systems and methods, are described. In some embodiments, fiber webs described herein may include fine fibers and relatively low amounts of degraded polymer formed during a fiber extrusion process. The fiber webs may be used for filter media applications.

Abstract: The present invention relates to a fixed bed, for example for the isolation and/or purification of components originating from a biological system, which fixed bed comprises magnetic beads and a magnetizable fabric arranged at least in part in the fixed bed, a fluidized bed-fixed bed, which comprises the fixed bed of the invention after application of an alternating magnetic field, and also to a process for the isolation and/or purification of components originating from a biological system.

Abstract: A filtering machine (10) for filtering a condensate which includes entrained oily contaminant, the machine (10) including a filter (14) through which the condensate passes from an inlet (17), to a main filter chamber outlet (24), the filter (14) including an exterior housing (15) through which the condensate, in use, passes into a filter interior, and through which filtrate, in use, passes from the filter interior, and the filter interior including a mass of filter material which includes silica-based oleophillic fibres (29).

Abstract: An automatic oil-water separation and recovery device, which comprises a cylindrical tank, on the top of which exists an oil collector. The tank has an inflow pipe that links to a pre-separation regulating water distributor therein. The said water distributor is in the shape of an obconic bell mouth. At the lower part of the tank stands an outflow collector on which a bar-shaped oil-water separation unit is secured. The said outflow collector has an outlet. The said oil-water separation unit is made from stainless steel or plastic antipriming pipe firstly wrapped with unwoven cloth, and then taped with wires and outside the wires further wrapped with nonwoven cloth. All the cloth and wires are made of the same highly hydrophilic, oil-resistant material. The automatic oil-water separation and recovery devices described in this invention can be assembled together for separating and recovering ship-generated oily water.

Abstract: The present invention relates to a method for manufacturing a depth filter sheet material, the method comprising preparing a flowable aqueous pulp composition comprising a fibrous material and a binding agent; dispensing the flowable aqueous pulp composition onto a water permeable support in a predetermined amount per unit area; at least partially draining the water content of the aqueous pulp composition through said water permeable support; drying the at least partially drained pulp composition at an elevated temperature to form a depth filter sheet raw material comprising a first and a second surface section forming an upper and a lower surface of the sheet raw material, respectively, and an intermediate section positioned in between and integrally formed with the first and the second surface sections, the intermediate section having a permeability greater than the permeability of the first and second surface sections; and removing or displacing at least portions of one of the first or second surface secti

Abstract: A multi-layer filter media including at least one layer of melt-blown fiber filter media and at least one layer of electrospun nanofiber filter media is provided. The multi-layer filter media of the present invention is configured such that the at least one layer of the melt-blown fiber filter media is on the upstream and the at least one electrospun nanofiber filter media is positioned downstream of the at least one melt-blown fiber filter media.

Abstract: A method for removing microorganisms from liquid samples and a nanofiber containing liquid filtration medium that simultaneously exhibits high liquid permeability and high microorganism retention. Microorganisms such as bacteria, particularly B. Diminuta, are removed from a liquid by passing the liquid through a porous nanofiber containing filtration medium having a B. Diminuta LRV greater than about 9, and the nanofiber(s) has a diameter from about 10 nm to about 1,000 nm. Another method for removing microorganisms such as bacteria and Mycloplasma, includes passing the liquid through a porous nanofiber containing filtration medium having a microorganism LRV greater than about 8, and the nanofiber(s) has a diameter from about 10 nm to about 1,000 nm. The filtration medium can be in the form of a fibrous electro spun polymeric nanofiber liquid filtration medium mat.

Abstract: Disclosed is a media (such as a filter media) having one or more carbon nanotube (CNT)-containing layer. Each CNT-containing layer contains high temperature refractory fibers (e.g., staple quartz fibers and/or ceramic refractory fibers) that have melting temperatures greater than about 600° C. and in situ grown CNTs. Substantially all of the in situ grown CNTs have one end thereof associated with the fibers. This results in substantially all of the in situ grown CNTs extending away from substantially all of the fibers. Moreover, substantially all of the in situ grown CNTs are dispersed throughout the fibers. In one embodiment the media also includes one or more supporting layer. Each supporting layer contains high temperature refractory fibers that have melting temperatures greater than about 600° C., optionally bulk refractory fibers, optionally E-glass fibers, and optionally microglass fibers.

Abstract: An improved air/oil separator assembly for removal of oil from a gaseous stream is disclosed. The air/oil separator includes a head flange and an end plate positioned in a spaced-parallel relationship. A first and a second elongated support member and an outer jacket are concentrically arranged and secured along opposing ends to the head flange and end plate. A first separator element is secured in a position proximate to and outboard of the first support member and a second separator element is secured in a position proximate to and outboard of the second support member. A pre-separator element is secured in a position proximate to and outboard of the second separator element but inboard of the outer jacket. The pre-separator and separator elements are operative to remove oil from the gaseous stream. The pre-separator improves oil removal performance by removing a significant amount of oil before it reaches the separator elements.

Abstract: A filtration unit for the selective elimination of a target substance from a biological fluid comprising an external envelope, wherein the envelope encloses a filtering medium comprising: an upstream structure for eliminating at least the target substance comprising a stack of layers that are arranged to allow the flow of fluid through the layers in one direction comprising a non-woven material, and particles interposed between at least some of the layers, wherein the particles have an affinity for the target substance; and a downstream structure for retaining the particles comprising at least one layer of porous material.