Abstract: A diffusiophoretic water filtration device has a pressurizable gas chamber for receiving a pressurized gas; an inlet manifold for receiving a colloidal suspension including colloidal particles in water; a flow chamber having an inlet and an outlet, the flow chamber for receiving the colloidal suspension at the inlet from the inlet manifold, the colloidal suspension flowing between the inlet and at least one outlet in a flow direction; and a gas membrane separating the gas chamber and the flow chamber, the sheet being made of a gas permeable membrane, the pressurized gas capable of permeating the membrane, the membrane being water impermeable, the gas membrane having a first side facing the pressurized gas chamber, and a second side facing the flow chamber, the flow chamber having a plurality of channels, each channel contacting the second side of the membrane; and an outlet splitter separating a first outlet from a second outlet and splitting the plurality of channels, the first outlet for receiving water hav

Abstract: Provided is a device for electrical measurement designed to be able to perform high sensitivity detection by reading not only changes in steady-state current, but also the occurrence of transient current, and an electrical measurement apparatus including the device for electrical measurement. The device for electrical measurement includes a substrate on which are formed at least a sample separation channel and a sample migration channel, as well as a sample measuring unit, with one end of the sample separation channel formed to connect to one end of the sample migration channel, and the sample measuring unit including a first measuring unit connected to the sample migration channel, and a second measuring unit connected to the sample migration channel from the reverse side to the first measuring unit.

Abstract: An apparatus for detecting chemical reactions may be provided. The apparatus may comprise a chemical detection device. The chemical detection device may include a chemical sensor, which may be mounted on the chemical detection device. The apparatus may further comprise a valve block. The valve block may fluidly couple a plurality of reagent containers to the chemical detection device. The apparatus may further comprise a heat exchanger and a controller. The controller may control a fluid connection between the valve block and the chemical detection device. The controller may be also configured to adjust a temperature of a selected reagent from the plurality of reagent containers via the heat exchanger. The temperature of the selected reagent may be adjusted prior to the reagent entering the chemical detection device.

Abstract: Devices and methods are provided for electrically lysing cells and releasing macromolecules from the cells. A microfluidic device is provided that includes a planar channel having a thickness on a submillimeter scale, and including electrodes on its upper and lower inner surfaces. After filling the channel with a liquid, such that the channel contains cells within the liquid, a series of voltage pulses of alternating polarity are applied between the channel electrodes, where the amplitude of the voltage pulses and a pulsewidth of the voltage pulses are effective for causing irreversible electroporation of the cells. The channel is configured to possess thermal properties such that the application of the voltage produces a rapid temperature rise as a result of Joule heating for releasing the macromolecules from the electroplated cells. The channel may also include an internal filter for capturing and concentrating the cells prior to electrical processing.

Abstract: The present invention provides methods for determining chromatography separation conditions; for example, separation of a polypeptide and its charge variants. The invention also provides methods to determine a buffer condition for chromatography separation conditions. The invention also provides a robust method to analyze multiple polypeptide products.

Abstract: A specified proton concentration in a volume (80) is produced by passing a controlled electrophoresis current through an adjacent electrophoresis volume (28) between a working electrode (26) and a counter electrode (24). An array of such volumes with specified proton concentration is used to provide the pH gradient for isoelectric focusing.

Abstract: A kit for separating and concentrating nucleic acid and protein targets includes labeled reagents which affect simultaneous co-purification and concentration of a nucleic acid and a protein, a gel isotachophoresis separation unit to which a sample comprising the nucleic acid and the protein is added, a detection unit for the detection of the presence of the nucleic acid and the protein, and instructions for use. The gel electrophoresis includes a gel box having a negative electrode side and a positive electrode side, the negative electrode side being filled with a first buffer comprising 2-Hydroxy-N-(tris(hydroxymethyl)methyl)-3-aminopropanesulfonic acid buffer and the positive electrode side being filled with a second buffer being different than the first buffer. The gel isotachophoresis separation is configured to subject the sample to isotachophoresis using a voltage.

Abstract: To separate solid matter contained in a liquid phase in a membrane separation tank 2, a pH of the liquid phase is adjusted to make a surface charge of the solid matter electrically homopolar with a surface charge of a ceramic flat membrane 3 to separate the solid matter from the liquid phase. Alternatively, by adding, to the liquid phase, a charge adjusting agent having a surface charge electrically homopolar to a surface charge of the ceramic flat membrane 3 and electrically heteropolar to a surface charge of the solid matter, the surface of the solid matter is charged to have an apparent surface charge electrically homopolar to the surface charge of the inorganic membrane 3.

Abstract: Water-soluble, UV-absorbing and/or fluorescing compound having an isoelectric point greater than 10, can be obtained using molecules chosen from the group of molecules consisting of those containing at least one secondary alcohol OH group with a pKa value greater than 10 and at least one amino group with a pKb value smaller than 5, those containing at least one primary alcohol OH group and at least one secondary alcohol OH group with respective pKa values greater than 10 and at least one amino el group with a pKb value smaller than 5 or a quaternary ammonium group, and those containing at least two secondary alcohol OH groups with respective pKb values greater than 10 and at least one amino group with a pKb value smaller than 5 or a quaternary ammonium group; and having at least one UV absorbing group or at least one fluorescing group or a combination thereof. The invention includes methods for producing such compounds.

Abstract: A device for isoelectric focusing. The device comprises a focusing container configured to contain an electrolyte solution and having a longitudinal axis and at least one electrolysis unit mounted in a close proximity to the longitudinal axis. Each electrolysis unit injects an ion flow into the focusing container so as to create a pH gradient having a plurality of steps in the electrolyte solution, along the longitudinal axis. Each step has a substantially uniform pH level and the pH gradient is defined by at least one pH ramp between every two sequential steps of the plurality of steps.

Abstract: The present invention provides methods for adsorbing a protein onto a conductive solid substrate, comprising the application of an external potential to the solid substrate greater than +500 mV vs. the Ag/AgCl/Cl?SAT reference electrode, in the presence of a solution comprising the protein, wherein the solution has a pH within + 2 units of the isoelectric point of the protein, and wherein the protein adsorbs to the conductive solid substrate upon application of the external potential. Some embodiments are directed to a process of protein adsorption on a solid surface mediated by an applied potential that can be affected significantly by altering a number of variables such as protein concentration, flexibility, charge, molecular weight, pH, and charge of substrate.

Abstract: Improved electrophoretic analysis is provided by interaction of anionic and cationic isotachophoresis (ITP) shock waves that propagate toward each other, and analysis of the resulting interaction zones. These shock wave interactions can provide qualitatively different capabilities from conventional ITP methods. Shock wave interaction can enable a single assay to identify analyte and quantify its concentration via isotachophoretic focusing followed by separation of the concentrated analytes via electrophoresis, without any mid-assay alteration of the externally imposed experimental conditions (i.e., no switching, valve operation, etc. during the measurement). As another example, shock wave interaction can enable a single assay to provide coupled ITP processes with different electrolyte concentrations (as in cascade-ITP) in a single simple system (again, without any mid-assay alteration of the externally imposed experimental conditions).

Abstract: An apparatus and method for measuring the isoelectric pH for materials deposited on or otherwise affixed onto and in contact with an electrode surface, and a method for utilizing the isoelectric pH to form nanometer thickness, self-assembled layers on the material, are described. Forming such layers utilizing information obtained about the isoelectric pH values of the substrate and the coating is advantageous since the growth of the coating is self-limiting because once the surface charge has been neutralized there is no longer a driving force for the solid electrolyte coating thickness to increase, and uniform coatings without pinhole defects will be produced because a local driving force for assembly will exist if any bare electrode material is exposed to the solution. The present self-assembly procedure, when combined with electrodeposition, may be used to increase the coating thickness.

Abstract: Electrophoresis Compositions, methods and kits useful for, among other things, detecting, quantifying and/or characterizing analytes are provided. The compositions are useful as electrophoresis standards for determine the isoelectric point and molecular weight of an analyte. The electrophoresis standards generally comprise at least one label moiety and one or more reactive moieties that when activated attach the standard to a substrate.

Abstract: A device for electro membrane extraction has a syringe holder adapted to hold a syringe having an acceptor solution, and a sample vial holder adapted to hold a sample vial having a vial cap, where the vial cap includes an inside funnel to be equipped with a prewetted hollow fiber membrane having a tube like shape sealed at the end opposite the funnel and forming a lumen, and steering guides for at least two electrodes, a first electrode to be immersed in a donor solution placed in the sample vial, a second electrode to be immersed, through the funnel in the vial cap, into the lumen of the hollow fiber membrane, and a positioning device for sliding the first electrode in and out of the donor solution in the sample vial and for sliding the second electrode in and out of the lumen of the hollow fiber membrane.

Abstract: UV-Absorbing and fluorescent pl markers for isoelectric focusing separations and fluorescent labeling, and methods for making and using the markers.

Abstract: Electroadsorption and charged based biomolecule separation, concentration and detection with porous biosensors. In preferred embodiments, a potential is applied to a porous electrode to separate and concentrate molecules from solution. The bimolecular analytes are captured by the porous electrode itself, the same electrode that is used to generate the electric field for electroadsorption. In additional preferred embodiments, pH of the solution is adjusted to separate and concentrate biomolecules. Setting the pH equal to the protein isoelectric point was determined by the inventors to maximize concentration of biomolecules into the porous biosensor. The methods include simultaneously optically detecting charged molecules captured by the porous electrode. Methods of the invention are benign to biomolecules of interest, which are demonstrated to retain a high percentage of their activity after being released from the biosensor. Methods of the invention provide label-free detection.

Abstract: An aligned polymer article including substrates, wherein the substrates are not covalently bonded to the aligned collagen and a method of forming such articles wherein substrates are mixed with a polymer in solution to form a polymer-substrate mixture. The mixture is placed in an electrochemical cell and a voltage is applied to the cell generating a pH gradient, wherein the polymer aligns in the cell and migrates to the isoelectric plane of the polymer solution.

Abstract: Disclosed is a novel microfluidic device enabling on-chip implementation of a two-dimensional separation methodology. Previously disclosed microscale immobilized pH gradients (IPG) are combined with perpendicular polyacrylamide gel electrophoresis (PAGE) microchannels to achieve orthogonal separations of biological samples. Device modifications enable inclusion of sodium dodecyl sulfate (SDS) in the second dimension. The device can be fabricated to use either continuous IPG gels, or the microscale isoelectric fractionation membranes we have also previously disclosed, for the first dimension. The invention represents the first all-gel two-dimensional separation microdevice, with significantly higher resolution power over existing devices.

Abstract: An electrophoresis method is provided involving a parallel and simultaneous multiple process, using multiple separation sub-spaces within a separation chamber.

Abstract: A novel method for visualizing electrokinetic process zones (e.g., for isotachophoresis (ITP)) is provided. We introduce negligibly small concentrations of a fluorophore that is not focused by isotachophoresis. This non-focusing tracer (NFT) migrates through multiple isotachophoresis zones. As it enters each zone, the NFT concentration adapts to the local electric field in each zone. ITP zones can then be visualized with a point detector or camera. The method can be used to detect, identify, and quantify unknown analyte zones, and can visualize complex and even transient electrophoresis processes. This visualization technique is particularly suited to microfluidic and lab-on-a-chip applications, as typical fluorescence microscopes and CCD cameras can provide high-resolution spatiotemporal data.

Abstract: An improved method of separating a macromolecule by isoelectric focusing comprising subjecting the macromolecule to electrophoresis in an isoelectric-focusing medium including a substantially thiol-free reducing agent, preferably a trivalent phosphorous compound and more preferably tributyl phosphine, the improvement being the solubility and focusing of the macromolecule is enhanced compared to isoelectric focusing of the same macromolecule in a similar isoelectric-focusing medium containing a thiol-reducing agent.

Abstract: A device for electrophoresis applies a voltage to a medium in contact with a plurality of electric conductors so that a potential of adjacent conductors is within a certain range. This allows preventing decline in electrophoresis speed. A device for electrophoresis and transfer includes an electrode having a plurality of electrode regions being insulated one another and arranged in a specific direction. This allows providing a practical and easy-to-use device for electrophoresis and transfer. A device for transfer alters an applied voltage or applied voltage duration to a certain position to another position. This allows improving transfer efficiency.

Abstract: A method and apparatus for continuously separating or concentrating molecules that includes flowing two fluids in laminar flow through an electrical field and capturing at one of three outputs a fluid stream having a different concentration of molecules.

Abstract: Provided are a method and apparatus for measuring an isoelectric point using a field effect transistor. The method includes providing a field effect transistor including a substrate, source and drain electrodes disposed on the substrate and spaced apart from each other, and a channel region between the source and drain electrodes, providing a first electrolyte solution having a first concentration to the channel region of the field effect transistor and measuring a first current value of the channel region between the source and drain electrodes, providing a second electrolyte solution having a second concentration greater than the first concentration and measuring a second current value of the channel region between the source and drain electrodes, and determining the isoelectric point of the field effect transistor or a material disposed on the field effect transistor using a difference between the first and second current values.

Abstract: The present inventions relate to micro-fluidic devices and related methods of fractionating samples of analytes, such as peptides or proteins, according to their isoelectric points. The disclosed micro-fluidic devices and related methods provide a fractionation sufficient to enhance the performance of immunochemistry and/or tandem liquid chromatography-mass spectrometry workflows. Such methods and devices are capable of fractionating complex samples in a short time, using a small amount of sample, do not require high voltages and are further characterized by their high degree of reproducibility and ease of use.

Abstract: A method of modifying the concentration of reactants and carrying out a chemical reaction on a microfluidic device in which first and second reactants are delivered into a reaction channel combined, the second reactant different from the first reactant and capable of reacting with the first reactant. The first reactant is subjected to a stacking process, thereby producing a first stacked reactant. The second reactant is subjected to the stacking process, thereby producing a second stacked reactant. The first stacked reactant is exposed to the second stacked reactant so that the first stacked reactant and the second stacked reactant undergo a chemical reaction.

Abstract: The present invention provides methods and separation media for separating analytes of interest via free flow electrophoresis (FFE) using volatile buffer systems. The separation media provided herein allow a convenient separation of the analytes by electrophoresis, and offer the additional advantage that the buffer compounds and the solvent can be easily and residue-free removed after the electrophoretic separation step. Furthermore, methods for mass spectrometric analysis of analytes comprising an FFE method and kits for carrying out FFE separations with volatile buffer systems are also provided. Preferably, the volatile buffer system is TRIS acetate.

Abstract: A sample separation/adsorption appliance (100) according to one embodiment of the present invention includes: a first buffer solution tank (103) equipped with a first electrode (101) and used for holding a first buffer solution; a second buffer solution tank (104) equipped with a second electrode (102) and used for holding a second buffer solution; a sample separation section (110) that holds a sample separation medium (131) for separating a sample; and a conductive section (120) that holds a conductive medium (133), wherein: the sample separation medium (131) and the conductive medium (133) are in contact with the sample adsorption member (132), respectively, on the opposite sides thereof; an end of the sample separation medium (131) opposite to an end being in contact with the sample adsorption member (132) is connected to an inside of the first buffer solution tank (103); and an end of the conductive medium (133) opposite to an end being in contact with the sample adsorption member (132) is connected to an

Abstract: The invention relates to the use of MS compatible surfactants in free-flow electrophoretic methods, which allow the separation of analytes with differentiated electrophoretic mobility. The surfactant is preferably a cleavable surfactant, such as PPS.

Abstract: Methods and devices for purification of different cell components from the same sample are provided.

Abstract: The present invention provides methods, compositions, and kits for protein crystallization. The present invention involves electrophoretically focusing at least a first protein species within a matrix comprising at least 2 regions of different pH, the protein being present in amount sufficient to permit crystallization within said pH gradient.

Abstract: The invention provides methods for detecting an interaction between an analyte and a biomolecule. The method comprises separating at least one biomolecule according to its isoelectric point in the presence of a given analyte and detecting an interaction between the analyte and a biomolecule using fluorescence anisotropy. The method may further comprise collecting the analyte-biomolecule complex and analyzing the biomolecule.

Abstract: The present invention generally relates to devices and methods for the separation of species, including biological species. Some embodiments involve the use of free flow isoelectric focusing (FF-IEF) devices in the separation of a mixture of species. Various device configurations and/or features may enhance the performance of the devices, providing faster and more efficient devices and methods for separating mixtures of species with high resolution. In some embodiments, separation of a mixture of species may be achieved with high resolution and with short sample residence times. Such devices may provide simplified, inexpensive, and optionally disposable devices for the separation of chemical and biological species and may optionally be integrated with orthogonal separation techniques, such as SDS-PAGE or capillary electrophoresis.

Abstract: Device and Process for isolating, purifying, concentrating and/or enriching at least one organic compound by electrokinetic migration through liquid membranes by use of an electronic potential and chambers with a preset pH value is described in the present application. The liquid membranes contain an organic solvent capable of transporting an ionized form of said at least one organic compound.

Abstract: Various embodiments provide an exemplary lab-on-a-chip (LOC) system that serves as an analytical tool and/or as a separation medium for an electrolyte solution including various charged molecular species. The LOC system can include an integrated nanofluidic FET device in combination with suitable analysis systems. By applying and controlling a longitudinal electric field and a transverse electric potential, the flow and the pH of the electrolyte solution in the nanofluidic channels can be controlled.

Abstract: Provided is a multi-channel apparatus for non-gel based two-dimensional protein separation. One or more flat channels are arranged in parallel and have an isoelectric focusing section for primarily separating proteins from protein samples according to isoelectric point (pI) and a flow field-flow fractionation section for secondarily separating the primarily separated proteins according to molecular weight, thereby making it possible to simultaneously separate the proteins in multiple channels, to increase a protein separation speed, and to overcome limitation to sample injection due to an increase in channel volume. The apparatus can separate the proteins according to pI and molecular weight, be safe from denaturation of the protein in the process of protein separation, automatically remove an ampholyte used for pI-based separation, and separately detecting the separated proteins to identify the proteins using nanoflow liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS-MS).

Abstract: A method for increasing measurement precision of two-dimensional protein electrophoresis is provided, in which the electrical conductivity of a protein sample under test is measured for calculating the electrical energy required to enable salt and protein focusing. The method is characterized by a set of equations for calculating the electrical energy required respectively for protein focusing and for electrophoresis of salts in the protein sample, wherein the calculation is based on the electrical conductivity of the salts, the protein weight, a pH-gradient gel strip length, and a pH range. Thus, different protein samples can be supplied with the appropriate amounts of electrical energy for isoelectric focusing, so as to produce the optimal protein focusing effects and ensure that the focusing of protein in a gel will not be adversely affected by an otherwise insufficient or excessive supply of electrical energy.

Abstract: Provided is a means for accurately analyzing a protease by electrophoresis. Disclosed is an electrophoretic analysis method for analyzing a protease-containing sample, is characterized by exposing a sample containing a protease to be analyzed, to pH conditions under which the protease is rapidly deactivated, and then subjecting the sample to electrophoresis.

Abstract: The present disclosure relates to methods and systems that may be used for analysis of nutraceutical associated components.

Abstract: A method of separating a mixture of a plurality of molecular analytes having different isoelectric points (pIs). The method comprises placing a solution containing a mixture of a plurality of molecular analytes in a separation volume, generating a pH profile having a plurality of pH zones across an axis of the separation volume, and adjusting a profile of the pH profile to induce a migration of a first molecular analyte along the axis apart from a second molecular analyte. The first and second molecular analytes having different pIs.

Abstract: Devices and methods are provided for separation of particles of a first selected electrophoretic mobility or isoelectric point from a fluid comprising particles of at least one other selected electrophoretic mobility or isoelectric point. The devices comprise a microchannel; electrodes to either side of the microchannel for applying a selected voltage to produce an electrical field across the microchannel orthogonal to the length of the microchannel; and outlets in said microchannel placed to receive outlet portions of the fluid containing enhanced concentrations of each type of particle. The devices may be used for particle detection, quantification, separation, mixing, dilution and concentration; to release, separate and detect interior particles of cells or organisms, and to separate particles such as proteins and microorganisms from biological fluids such as blood; or to separate and detect airborne contaminants such as bacterial warfare agents from air.

Abstract: The invention relates to a method of determining the risk of developing acute renal failure (ARF) in an individual, or of determining an ARF, and a method of predicting the progression of an ARF, by detecting and/or quantifying the protein Ganglioside GM2 Activator Protein (GM2AP). The failure can be due to the administration of at least one nephrotoxic agent, wherein the nephrotoxic agent can be an aminoglycoside antibiotic as for example gentamicin.

Abstract: An improved method of separating a macromolecule by isoelectric focusing comprising subjecting the macromolecule to electrophoresis in an isoelectric-focusing medium including a substantially thiol-free reducing agent, preferably a trivalent phosphorous compound and more preferably tributyl phosphine, the improvement being the solubility and focusing of the macromolecule is enhanced compared to isoelectric focusing of the same macromolecule in a similar isoelectric-focusing medium containing a thiol-reducing agent.

Abstract: An apparatus and method for measuring the isoelectric pH for materials deposited on or otherwise affixed onto and in contact with an electrode surface, and a method for utilizing the isoelectric pH to form nanometer thickness, self-assembled layers on the material, are described. Forming such layers utilizing information obtained about the isoelectric pH values of the substrate and the coating is advantageous since the growth of the coating is self-limiting because once the surface charge has been neutralized there is no longer a driving force for the solid electrolyte coating thickness to increase, and uniform coatings without pinhole defects will be produced because a local driving force for assembly will exist if any bare electrode material is exposed to the solution. The present self-assembly procedure, when combined with electrodeposition, may be used to increase the coating thickness.

Abstract: The invention provides devices for trapping and collecting separated biomolecules following a separation step. The invention also provides methods of using the devices to trap and collect separated biomolecules.

Abstract: The invention includes nanochannel devices and methods for using such nanochannel devices for separating molecules, ions and biomolecules. The nanochannel devices have at least one nanochannel through which fluid can move, wherein ionic double layers form in the fluid near walls of the nanochannel and those ionic double layers overlap within the nanochannel. Electrical voltage can be applied to the nanochannel to modify an electrostatic potential in the nanochannel and thereby control movement of ions and biomolecules through the nanochannel. The invention also includes arrays and networks of such nanochannel devices.

Abstract: Devices are provided for determining the isoelectric point of a charged analyte, comprising a titration chamber and an electrode chamber. The electrode chamber comprises at least two electrodes, for example, an electrode array. Either or both of the titration chamber and the electrode chamber may have a shaped geometry. The electrodes are operative, in conjunction with the shaped geometry of the chamber(s) where appropriate, to generate an electric field gradient in the titration chamber. Permeable material separates the titration chamber and the electrode chamber. A pH Sensor is located in the titration chamber for obtaining the pH of the first fluid. Certain preferred embodiments further include an analyte band detector for detecting the presence and optionally the location of a focused band of charged solute.

Abstract: The invention relates to a droplet actuator with a substrate comprising electrodes arranged for conducting droplet operations on a droplet operations surface of the substrate; a filler fluid phase in contact with the droplet operations surface at least partially surrounding a droplet phase comprising a droplet arranged on one or more of the electrodes, the droplet comprising: (i) a target substance susceptible to loss from the droplet phase into the filler fluid phase; and (ii) an additive which reduces loss of the target substance to the filler fluid phase relative to a corresponding droplet not comprising the additive. The invention also relates to various compositions and methods.

Abstract: This application discloses SNPs capable of predicting increased or decreased risk of developing late onset Alzheimer's disease.