1217results about "Amphoteric ion-exchangers" patented technology

A combination of acid zirconium phosphate and alkaline hydrous zirconium oxide are utilized as ion-exchange materials, for example, in sorbent dialysis. The combination provides for dialysate regeneration while maintaining constant and controlled levels of Na+, HCO3−, and pH.

The present invention provides a positively charged microporous membrane having a protein binding capacity about 25 mg / ml or greater comprising a hydrophilic porous substrate and a crosslinked coating that provides a fixed positive charge to the membrane. The present invention further provides a positively charged microporous membrane comprising a porous substrate and a crosslinked coating comprising pendant cationic groups. The membranes of the present invention find use in a variety of applications including ion-exchange chromatography, macromolecular transfer, as well as detection, filtration and purification of biomolecules such as proteins, nucleic acids, endotoxins, and the like.

A method for adsorption of a substance from a liquid sample on a fluidized bead or stirred suspension, in which the beads used comprise a base matrix and exhibit a structure having affinity to the substance, characterized in that the structure is covalently bound to the base matrix via an extender. Populations of beads in which the beads contain a filler incorporated in a base matrix and an extender are also described.

PCT No. PCT / SE97 / 00237 Sec. 371 Date Dec. 29, 1998 Sec. 102(e) Date Dec. 29, 1998 PCT Filed Feb. 14, 1997 PCT Pub. No. WO97 / 29825 PCT Pub. Date Aug. 21, 1997Process for separating off a peptide or a nucleic acid by an anion exchanger (I) characterized in that a) the anion exchanger (I) exhibits ligands, which (i) contain a primary, secondary or tertiary amino group and (ii) are covalently bound to an organic polymer (matrix), b) there on a carbon atom at a distance of 2 or 3 atoms away from an amino nitrogen in the ligands is a hydroxyl group or a primary, secondary or tertiary amino group, and c) the maximum elution ionic strength in the pH range 2-14 for at least one of the proteins transferrin, ovalbumin 1, ovalbumin 2, beta -lactoglobulin 1 and beta -lactoglobulin 2 on the anion exchanger is higher than the elution ionic strength required for a quaternary comparative ion exchanger.

A method for recovering inorganic salt during processing of a lignocellulosic feedstock is provided. The method comprises pretreating the lignocellulosic feedstock by adding an acid to the feedstock to produce a pretreated lignocellulosic feedstock. A soluble base is then added to the pretreated lignocellulosic feedstock to adjust the pH and produce a neutralized feedstock. The neutralized feedstock is then enzymatically hydrolyzed to produce an enzyme hydrolyzed feedstock and a sugar stream. Inorganic salt is recovered from either a stream obtained from the lignocellulosic feedstock prior to the step of pretreating, a stream obtained from the pretreated lignocellulosic feedstock, a stream obtained from the neutralized feedstock, a stream obtained from the sugar stream, or a combination of these streams. The inorganic salt may be concentrated, clarified, recovered and purified by crystallization, electrodialysis drying, or agglomeration and granulation, and then used as desired, for example as a fertilizer.

Media and devices, such as anion exchangers including such media, wherein the media is a membrane having a surface coated with a polymer such as a polyallylamine. The resulting membrane offers stronger binding of protein impurities and superior removal of host cell proteins from biological samples than conventional ligands based on quaternary ammonium salts, including trimethylammonium ligands. Also described is a chromatography scheme and method for purifying monoclonal antibodies, wherein the anion exchange sorber is placed downstream of an affinity column (such as Protein A or Protein G affinity column) and optionally one or more polishing devices such as cationic exchange columns. Little or no dilution of the cation exchanger pool (or affinity column exchange pool where no cation exchanger is used) is necessary to lower the conductivity of the sample. The sorber functions well to strongly bind host cell proteins and other impurities in biological samples even at high conductivities and pH.

A combination of acid zirconium phosphate and alkaline hydrous zirconium oxide are utilized as ion-exchange materials, for example, in sorbent dialysis. The combination provides for dialysate regeneration while maintaining constant and controlled levels of Na+, HCO3−, and pH.

A blood based solute monitoring system for measuring at least one blood solute species that has a first recirculation flow path in fluid communication with a dialyzer. The first recirculation flow path is configured to allow a fluid to recirculate through a dialyzer such that the concentration of at least one solute species in the fluid becomes equilibrated to the solute species concentration of the blood in a blood compartment of the dialyzer. The blood solute monitoring system has at least one sensor to measure a fluid characteristic.

A scalable alkaline lysis process, including procedures and devices for the isolation of large quantities (grams and kilograms) of plasmid DNA from recombinant E. coli cells. Effective, controllable, and economical operation, and consistent low level of host chromosomal DNA in the final plasmid product. Involves a series of new unit operations and devices for cell resuspension, cell lysis, and neutralization.

A material for chromatographic separations, processes for its preparation, and separation devices containing the chromatographic material. In particular, porous inorganic / organic hybrid monoliths are provided with a decreased concentration of surface organic groups, and have improved pH stability, improved chromatographic separation performance, and improved packed bed stability. These monoliths may be surface modified resulting in higher bonded phase surface concentrations and have enhanced stability at low pH.

A method for recovering inorganic salt during processing of a lignocellulosic feedstock is provided. The method comprises pretreating the lignocellulosic feedstock by adding an acid to the feedstock to produce a pretreated lignocellulosic feedstock. A soluble base is then added to the pretreated lignocellulosic feedstock to adjust the pH and produce a neutralized feedstock. The neutralized feedstock is then enzymatically hydrolyzed to produce an enzyme hydrolyzed feedstock and a sugar stream. Inorganic salt is recovered from either a stream obtained from the lignocellulosic feedstock prior to the step of pretreating, a stream obtained from the pretreated lignocellulosic feedstock, a stream obtained from the neutralized feedstock, a stream obtained from the sugar stream, or a combination of these streams. The inorganic salt may be concentrated, clarified, recovered and purified by crystallization, electrodialysis drying, or agglomeration and granulation, and then used as desired, for example as a fertilizer.

The present invention provides a positively charged microporous membrane having a protein binding capacity of about 25 mg / ml or greater comprising a hydrophilic porous substrate and a crosslinked coating that provides a fixed positive charge to the membrane. The present invention further provides a positively charged microporous membrane comprising a porous substrate and a crosslinked coating comprising pendant cationic groups. The membranes of the present invention find use in a variety of applications including ion-exchange chromatography, macromolecular transfer, as well as detection, filtration and purification of biomolecules such as proteins, nucleic acids, endotoxins, and the like.

A scalable alkaline lysis process, including procedures and devices for the isolation of large quantities (grams and kilograms) of plasmid DNA from recombinant E. coli cells. Effective, controllable, and economical operation, and consistent low level of host chromosomal DNA in the final plasmid product. Involves a series of new unit operations and devices for cell resuspension, cell lysis, and neutralization.

A system for measuring at least one fluid characteristic at various stages within a sorbent system that has a sorbent cartridge that has at least one material layer and at least one fluid passageway in at least one location in the sorbent system to provide a diverted sample stream from the various stages. At least one fluid characteristic of the diverted sample stream is measured.

A novel sorbent suitable for use as a stationary phase in a chromatography column, the core of which consists of an organic polymer of synthetic or natural origin. Further, the carrier exhibits a plurality of covalently bonded non-aromatic zwitterionic groups on its surface. Additionally, the invention also relates to a method for purifying a particular biological macromolecule, such as a protein or a nucleic acid, by zwitterionic ion exchange chromatography as well as an ion exchange column suitable for use in the zwitterionic ion exchange chromatography.

It is the purpose of the present invention to provide filter cartridges which can suitably be utilized in purifying chemical fluids for treating the surface of an electronic device substrate to be used in the semiconductor industry, particularly fluids containing a basic compound such as ammonia and an ammonium salt, or hydrofluoric acid (HF). The filter cartridges relating to the present invention which are used in removing metallic impurities contained in a chemical fluid for treating the surface of an electronic device substrate by treating the chemical fluid, is characterized by having a filter material incorporated therein, into which functional groups compatible with the existing morphology of the metallic impurities to be removed are incorporated in compliance with the constituents of the chemical fluid to be treated and the types of the metallic impurities to be removed.

A method for purifying a polypeptide by ion exchange chromatography is described in which a gradient wash is used to resolve a polypeptide of interest from one or more contaminants.

Disclosed is an air-water-catalyst-UV light contacting, air heating and cooling, humidifying and dehumidifying CHAMBER, which receives water that continuously recirculates through the water filtering, heating and cooling, (and deionizing) loop, which gets fresh outdoors air through the energy-efficient heat exchanger, which generates water from the atmospheric moisture, which stores and recirculates pure water through potable water holding tank, and to which is connected a novel design energy-efficient self-regulating steam distillation apparatus. Also, a water filtration system utilizing zwitterionic polymers as ion exchange and salt-absorbing and filtration media. Also disclosed are novel ionic and zwitterionic polymers, derived from cellulose.

A pavement material for the capture of waterborne constituents. The pavement material comprises a porous pavement substrate and an amphoteric compound bonded to the substrate. The porous pavement material may have a hydraulic conductivity ranging from about 0.001 to about 1.0 cm / sec and may act as a storm water storage basin.

The invention discloses a preparation method of an amphoteric ion exchange membrane and relates to a preparation method of an amphoteric ion exchange membrane for an all-vanadium redox flow battery. According to the scheme, the preparation method comprises the following steps of: performing irradiation grafting on polymer powder poly(vinylidene fluoride); transforming the irradiation-grafted polymer powder into a membrane material; and sulfonating the membrane material, hydrolyzing, introducing a sulfonate radical group with a cationic exchange function, putting the membrane material into a hydrochloric acid aqueous solution for undergoing a protonation reaction and introducing basic nitril with an anion exchange function to obtain the amphoteric ion exchange membrane. In the method, commercial poly(vinylidene fluoride) resin with low price is taken as a raw material, so that the membrane making cost can be lowered; a C-F bond has large bond energy, so that the membrane can keep high chemical stability in a strong acid and high oxidizing electrochemical environment; and meanwhile, the problem of non-uniform distribution of grafted chains of the conventional heterogeneous irradiation-grafted membrane in the vertical direction of the membrane is solved.

A method for purifying a polypeptide by ion exchange chromatography is described in which a gradient wash is used to resolve a polypeptide of interest from one or more contaminants.

The present invention provides methods for separating one or more components of interest from a sample containing particulates and soluble materials. The method comprises the steps of: (a) filtering a sample through silica filter media whose surface silanol groups have reacted with one or more silanes, and (b) simultaneously capturing particulates and binding a soluble component to the silica filter media. The bound soluble component of interest is subsequently eluted from the silica filter media. In one embodiment of the invention, unwanted soluble materials are captured by the treated silica filter media and desired component of interest is recovered from the flow-through. In another embodiment of the invention, different components of interest are recovered from both the eluate and the flow-through. Preferred treated silica filter media are silane-treated rice hull ash or diatomaceous earth with functional quaternary ammonium group or functional sulphonate group. Particulates suitable for the present invention, for example, are microorganisms.

A method for making an ion exchange coating (e.g., a chromatographic medium) on a substrate comprising (a) reacting at least a first amine compound comprising amino groups, with at least a first polyfunctional compound, in the presence of a substrate to form a first condensation polymer reaction product, with a first unreacted excess of either at least said first amino group or polyfunctional compound functional moieties, irreversibly attached to the substrate, and (b) reacting at least a second amine compound or at least a second polyfunctional compound with unreacted excess in the first condensation polymer reaction product to form a second condensation polymer reaction product, and repeating the steps to produce the desired coating. A coated ion exchange substrate so made.

The invention relates to a system and a process for fractionating a solution into two or more fractions. The system of the invention comprises at least two compartments having a diameter of at least about one meter and including a uniform packing of a polymer-based ion exchange resin with a bead size in the range of about 50 to about 250 mum. The mixing volume of the fluid fronts in the system of the invention is not more than 5% of the volume of the compartment.

The present invention relates to a method of separating sugars and sugar alcohols from each other. More particularly the present invention relates to the use of a weakly basic anion exchange resin in a chromatographic separation process. The advantage of the present invention compared with the prior art is that it is especially suitable for separating reducing sugars in acidic conditions as well as for example in weakly acidic conditions. The method using chromatographic separation comprises at least one step where a weakly basic anion exchange resin is used in a chromatographic column or in a part of a column.

Described herein are fluid treatment devices for use in tangential flow filtration, comprising a housing unit and a composite material, wherein the composite material comprises: a support member comprising a plurality of pores extending through the support member; and a non-self-supporting macroporous cross-linked gel comprising macropores having an average size of 10 nm to 3000 nm, said macroporous gel being located in the pores of the support member. The invention also relates to a method of separating a substance from a fluid, comprising the step of placing the fluid in contact with an inventive device, thereby adsorbing or absorbing the substance to the composite material contained therein.

The present invention relates to a method of isolating a target compound from other components of a liquid, which method comprises at least two chromatographic steps, in any sequence of order, wherein the mobile phase is contacted with an affinity chromatography matrix and / or an ion-exchange chromatography matrix and / or a hydrophobic interaction chromatography matrix, wherein the contacting with at least one of the matrices takes place in the presence of at least one non-ionic polyether; and obtaining the target compound(s) in a separate fraction from the last chromatographic step. In the most preferred embodiment, the non-ionic polyether is poly(ethylene glycol) (PEG).

The invention provides novel methods for the separation of charged molecules such as proteins according to the isoelectric points (pI's) and includes the systems and buffering compositions employed for isolating charged molecules. The invention further provides for modifications to the above described chromatographic methods that enable the separation of charged molecules exhibiting virtually identical pI's by shifting both the buffer's pKa and the pI's of the eluted charged molecules while they are traversing the ion exchange column.