Abstract: A porous substrate capable of adsorptive filtration of a fluid having a porous self-supporting substrate and one or more porous, adsorptive polymeric coatings comprising from about 1 to about 80% of the void volume of the pores of the substrate. The resultant substrate has good convective and diffusive flow and capacity. The substrate may be cross-linked, have one or more capture chemistries attached to it and is useful as a chromatography media for the selective filtration of desired species including biomolecules such as proteins and DNA fragments.

Abstract: A porous substrate capable of adsorptive filtration of a fluid having a porous self-supporting substrate and one or more porous, adsorptive polymeric coatings comprising from about 1 to about 80% of the void volume of the pores of the substrate. The resultant substrate has good convective and diffusive flow and capacity. The substrate may be cross-linked, have one or more capture chemistries attached to it and is useful as a chromatography media for the selective filtration of desired species including biomolecules such as proteins and DNA fragments.

Abstract: A porous substrate capable of adsorptive filtration of a fluid having a porous self-supporting substrate and one or more porous, adsorptive polymeric coatings comprising from about 1 to about 80% of the void volume of the pores of the substrate. The resultant substrate has good convective and diffusive flow and capacity. The substrate may be cross-linked, have one or more capture chemistries attached to it and is useful as a chromatography media for the selective filtration of desired species including biomolecules such as proteins and DNA fragments.

Abstract: A porous substrate capable of adsorptive filtration of a fluid having a porous self-supporting substrate and one or more porous, adsorptive polymeric coatings comprising from about 1 to about 80% of the void volume of the pores of the substrate. The resultant substrate has good convective and diffusive flow and capacity. The substrate may be cross-linked, have one or more capture chemistries attached to it and is useful as a chromatography media for the selective filtration of desired species including biomolecules such as proteins and DNA fragments.

Abstract: A porous substrate capable of adsorptive filtration of a fluid having a porous self-supporting substrate and one or more porous, adsorptive polymeric coatings comprising from about 1 to about 80% of the void volume of the pores of the substrate. The resultant substrate has good convective and diffusive flow and capacity. The substrate may be cross-linked, have one or more capture chemistries attached to it and is useful as a chromatography media for the selective filtration of desired species including biomolecules such as proteins and DNA fragments.

Abstract: A porous substrate capable of adsorptive filtration of a fluid having a porous self-supporting substrate and one or more porous, adsorptive coatings comprising from about 1 to about 80% of the void volume of the pores of the substrate. The resultant substrate has good convective and diffusive flow and capacity. The substrate may be crosslinked, have one or more capture chemistries attached to it and is useful as a chromatography media for the selective filtration of desired species including biomolecules such as proteins and DNA fragments.

Abstract: Compositions and methods for selectively binding specific metal ions, such as Ca2+ and Cd2+, contained in a source solution are disclosed and described. This is accomplished by the use of a composition comprised of an EGTA ligand covalently bonded to a membrane support. The composition formula of the present invention is M—B—L where M is a membrane having a hydrophilic, partially hydrophilic or a composite membrane with a hydrophilic surface, B is a covalent linkage, and L is an EGTA ligand. The separation is accomplished by passing a source solution containing the ions to be separated through a device containing the membrane-ligand composition, causing the selected ions to be complexed to the EGTA ligands and subsequently removing the selected ions from the device by passing an aqueous receiving solution through the device and quantitatively stripping the selected ions from the EGTA ligand.

Abstract: The invention pertains to a method for removing metallic ions and/or particulate material from an aqueous acid solution using particle removing membranes (e.g., ultra high molecular weight polyethylene) having immobilized ligand groups (e.g., macrocycle or other similar chelating ligands) that possess high equilibrium binding constants for ion and particulate removal. The method is particularly useful for simultaneously filtering/purifying aqueous hydrofluoric or hydrochloric acid.

Abstract: Compositions and methods for selectively binding specific metal ions, such as Ca2+ and Cd2+, contained in a source solution are disclosed and described. This is accomplished by the use of a composition comprised of an EGTA ligand covalently bonded to a membrane support. The composition formula of the present invention is M-B-L where M is a membrane having a hydrophilic, partially hydrophilic or a composite membrane with a hydrophilic surface, B is a covalent linkage, and L is an EGTA ligand. The separation is accomplished by passing a source solution containing the ions to be separated through a device containing the membrane-ligand composition, causing the selected ions to be complexed to the EGTA ligands and subsequently removing the selected ions from the device by passing an aqueous receiving solution through the device and quantitatively stripping the selected ions from the EGTA ligand.

Abstract: The present invention provides methods for removing species of ions from biological solutions, thereby allowing controlled study of the biological effect of one or more ion on a biological system or environment. In general, a solution from which one or more ion species are to be removed is contacted with an ion binding ligand having an affinity for the desired ion wherein the ligand is bound to a substrate such as a solid support or membrane. After the ions have been bound by the ligand-substrate composition, the composition having the ions bound thereto is removed, leaving a solution with a reduced concentration of the one or more ions which were targeted. The biological solution may then be compared to a control biological solution in its original state, or ions may added back into the depleted biological solution at known concentrations. Under either scenario, the biological effects of one or more ions may be studied.

Abstract: Methods, compositions and devices for purifying polypeptides and/or proteins using metal loaded ligand bound membranes by metal ion affinity chromatography are described.

Abstract: Compositions and methods for selectively binding specific metal ions, such as Ca2+ and Cd2+, contained in a source solution are disclosed and described. This is accomplished by the use of a composition comprised of an EGTA ligand covalently bonded to a membrane support. The composition formula of the present invention is M-B-L where M is a membrane having a hydrophilic, partially hydrophilic or a composite membrane with a hydrophilic surface, B is a covalent linkage, and L is an EGTA ligand. The separation is accomplished by passing a source solution containing the ions to be separated through a device containing the membrane-ligand composition, causing the selected ions to be complexed to the EGTA ligands and subsequently removing the selected ions from the device by passing an aqueous receiving solution through the device and quantitatively stripping the selected ions from the EGTA ligand.

Abstract: The present invention provides methods for removing species of ions from biological solutions, thereby allowing controlled study of the biological effect of one or more ion on a biological system or environment. In general, a solution from which one or more ion species are to be removed is contacted with an ion binding ligand having an affinity for the desired ion wherein the ligand is bound to a substrate such as a solid support or membrane. After the ions have been bound by the ligand-substrate composition, the composition having the ions bound thereto is removed, leaving a solution with a reduced concentration of the one or more ions which were targeted. The biological solution may then be compared to a control biological solution in its original state, or ions may added back into the depleted biological solution at known concentrations. Under either scenario, the biological effects of one or more ions may be studied.

Abstract: The invention pertains to a method for removing metallic ions and/or particulate material from an aqueous acid solution using particle removing membranes (e.g., ultra high molecular weight polyethylene) having immobilized ligand groups (e.g., macrocycle or other similar chelating ligands) that possess high equilibrium binding constants for ion and particulate removal. The method is particularly useful for simultaneously filtering/purifying aqueous hydrofluoric or hydrochloric acid.

Abstract: The invention pertains to a method for simultaneously removing metallic ions and particulate material from a pH neutral solution using particle-removing membranes (e.g., ultra high molecular weight polyethylene) having immobilized ligands that possess the capacity and high equilibrium binding constants for ion removal. The method is particularly useful for simultaneously filtering/purifying deionized water.

Abstract: The invention pertains to a method for removing metallic ions and/or particulate material from a pH neutral solution using particle-removing membranes (e.g., ultra high molecular weight polyethylene) having immobilized ligands that possess the capacity and high equilibrium binding constants for ion removal. The method is particularly useful for simultaneously filtering/purifying deionized water.

Abstract: Compositions and methods for selectively binding metal ions from a source solution comprise using a polyhydroxypyridinone-containing ligand covalently bonded to a membrane support having the formula M—A—L(HOPO)n. M is a membrane having a hydrophilic surface, A is a covalent linkage mechanism, L is a ligand carrier, HOPO is a hydroxypyridinone appropriately spaced on the ligand carrier to provide a minimum of six functional coordination metal binding sites, and n is an integer of 3 to 6. The separation is accomplished by passing a source solution containing the ions to be separated through a cartridge containing the membrane-ligand composition, causing the selected ions to be complexed to the HOPO ligands and subsequently removing the selected ions from the cartridge by passing an aqueous receiving solution through the cartridge and quantitatively stripping the selected ions from the HOPO ligand.

Abstract: A filtration process and apparatus are provided wherein feed fluid to be filtered is introduced into a small gap between two rectangular plates. At least one of the plates supports a porous filtration membrane within the gap. During filtration, at least one of the plates is oscillated to effect a continuously changing gradient of gap width between opposing surfaces of the plate. A permeate is collected and a seal is provided to prevent admixture of the permeate with either feed fluid or retentate.

Abstract: An improved water flow test for determining the integrity and/or pore size distribution of a porous filter is disclosed. The improvement involves the ability to determine and take into account the changes in filter structure due to filter compaction or creep resulting from compressive forces when pressure is applied to the surfaces of the filter. By proper characterization of the filter under test, the initial system volume and the volume change associated with pressurizing the filter can be accurately determined at all points in time during a test cycle. As a result, composite flowrate changes (i.e. the flow due to filter compaction/creep plus the flow due to liquid intrusion) can be evaluated to distinguish between various flow components to accurately determine the pore size of the filter being tested or a filter defect.

Abstract: A process is provided for rapidly and non-destructively evaluating the solute retention characteristics of porous membranes using a novel liquid-porosimetric technique. A ratio of two membrane permeabilities is measured at preselected operating conditions using a pair of mutually immiscible fluids, one of which is employed as a membrane wetting agent and the other used as an intrusion fluid. At the first operating condition, a particular transmembrane pressure is chosen so as to intrude nearly all of the pores present in the membrane sample. At the second operating condition, a particular membrane permeability is chosen so as to achieve a specified permeability ratio. The resulting transmembrane pressure corresponding to this particular membrane permeability is compared to a previously established standard curve which permits identifying the solute retention characteristics of the porous membrane.