Abstract: Disclosed are a method and apparatus that use an electric field for improved biological assays. The electric field is applied across a device having wells, which receive reactants, which carry a charge. The device thus uses a controllable voltage source between the first and second electrodes, which is controllable to provide a positive charge and a negative charge to a given electrode. By controlled use of the electric field charged species in a fluid in a fluid channel are directed into or out of the well by an electric field between the electrodes. The present method involves the transport of fluids, as in a microfluidic device, and the electric field-induced movement of reactive species according to various assay procedures, such as DNA sequencing, synthesis or the like.

Abstract: Disclosed is a method of driving an electrophoretic device that includes an electrophoretic element having a first electrode, a second electrode, and an electrophoretic layer disposed between the first and second electrodes, and further includes a capacitor connected to the first electrode at one terminal. The method includes (a) applying a reference potential or a first potential higher than the reference potential to the first electrode of the electrophoretic element and the terminal of the capacitor and applying the reference potential to the second electrode of the electrophoretic element, and (b) applying a signal fluctuating between a second potential and a third potential to the second electrode subsequently to the step (a), the second potential being equal to or higher than the reference potential, the third potential being higher than the second potential and being equal to or lower than the first potential.

Abstract: Methods and apparatuses for measuring streaming metrics. A method for measuring a streaming metric corresponding to a rotating surface is characterized by rotating the surface around an axis of rotation and measuring the streaming metric at a location within one radius from the axis of rotation and within three radii from the surface, wherein the location does not contact the surface. Apparatus for measuring a streaming metric corresponding to a rotating surface are characterized by a working electrode which does not contact the surface, a counter electrode, a meter connected to the working electrode and the counter electrode, a rotatable spindle on which the surface is mounted, and a container for holding electrolyte, wherein the working electrode, counter electrode, and surface are located within the container.

Abstract: Devices, systems, and methods employed in wet cleaning semiconductor devices are provided. In particular, systems that can deliver deionized water with the desired concentration of CO2 and methods of generating deionized water with a desired concentration of CO2 for use in wet cleaning of semiconductor devices are provided.

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: The patent describes a method for the simultaneous and repeatable separation of biological molecules by bidimensional electrophoresis and the apparatus usable to carry out thereof. And in particular, the present invention refers to a method and to an apparatus as defined above, capable to transfer and separate, on a matrix, of protein and/or polypeptide and/or peptide components that were previously ordered on another matrix according to specific chemical and/or physical characteristics.

Abstract: The present invention provides a method of indirectly detecting at least one directly undetectable analyte of interest. According to the method, a leading electrolyte and a trailing electrolyte are provided. In addition, a mixture of the at least one directly undetectable analyte and at least two directly detectable spacer molecules is provided. The directly detectable spacer molecules and the directly undetectable analyte are then concentrated and separated into zones using isotachophoresis. A displacement between the zones of directly detectable spacer molecules is then used to determine the presence of the directly undetectable analyte.

Abstract: An electrophoretic display panel for displaying a picture has a pixel having an electrophorectic medium having first and second charged particles, the first charged particles having a first optical property, the second charged particles having a second optical property different from the first optical property, and an optical state depending on positions of the particles. Furthermore, particle movement apparatus is arranged to enable a picture movement of the first and the second particles to their respective position for displaying the picture, and particles movement decoupling apparatus is arranged to provide unequal abilities of the first and the second particles to move for substantially decoupling the picture movement of the first particles from the picture movement of the second particles.

Abstract: The invention relates to a method and apparatus for carrier-free deflection electrophoresis, in which a separating media and a sample to be examined flow through a separating chamber between a pair of electrodes in a series of reversing bulk fluid flow along the direction of the electrodes, thereby separating the sample into zones which are to be collected into fractions for analysis or further processing. Among other things, the apparatus and method enable high-resolution separation of particles that can be performed in miniaturized chambers in electrophoresis modes including isoelectric focusing, zone electrophoresis, and isotachophoresis.

Abstract: In the present capillary electrokinetic chromatograpy method, analytes are injected by electroosmotic flow directly from a sample matrix into a separation buffer containing an electrokinetic vector with an opposite mobility. Analytes can now be injected at the velocity of electroosmotic flow, but are retained at the interface of the sample matrix-co-ion and separation buffer micelle zones as analyte/micelle complexes. Manipulation of the injecting force and opposing stacking force allow greatly increased length or volume of injection. Concentrations of the micelle, methanol, and borate in the separation buffer were provided to increase maximum injection length of neutral analytes. Reducing the analyte velocity in the separation buffer without substantially decreasing the velocity of the analyte during injection from the sample vial allowed greatly extended sample plug injection lengths. It is further enabled to inject sample solvent volumes equivalent to about twenty times the effective capillary volume.

Abstract: A method of, and apparatus for, automatically determining an electric charge—related characteristic or derived parameter of particles in a dispersion or of a cell wall, comprises having a particle—containing dispersion provided in a cell. The dispersion is illuminated with light from a light source and detecting from a detection volume light scattered from the particles. An electric field is applied to the dispersion at a first frequency of change of direction of the electric field and an electric field is subsequently applied to the dispersion at a second frequency of change of direction of the electric field. First signals detected from the scattered light when the first frequency electric field is applied are used to provide first values related to the velocity distribution of the particles.

Abstract: A method and apparatus for fractionation of a mixture of particles and for particle analysis are provided, in which LEAPS (“Light-controlled Electrokinetic Assembly of Particles near Surfaces”) is used to fractionate and analyze a plurality of particles suspended in an interface between an electrode and an electrolyte solution. A mixture of particles are fractionated according to their relaxation frequencies, which in turn reflect differences in size or surface composition of the particles. Particles may also be analyzed to determine their physical and chemical properties based on particle relaxation frequency and maximal velocity.

Abstract: A method and apparatus for the manipulation of colloidal particulates and biomolecules at the interface between an insulating electrode such as silicon oxide and an electrolyte solution. Light-controlled electrokinetic assembly of particles near surfaces relies on the combination of three functional elements: the AC electric field-induced assembly of planar aggregates; the patterning of the electrolyte/silicon oxide/silicon interface to exert spatial control over the assembly process; and the real-time control of the assembly process via external illumination. The present invention provides a set of fundamental operations enabling interactive control over the creation and placement of planar arrays of several types of particles and biomolecules and the manipulation of array shape and size. The present invention enables sample preparation and handling for diagnostic assays and biochemical analysis in an array format, and the functional integration of these operations.

Abstract: A method and apparatus for the manipulation of colloidal particulates and biomolecules at the interface between an insulating electrode such as silicon oxide and an electrolyte solution. Light-controlled electrokinetic assembly of particles near surfaces relies on the combination of three functional elements: the AC electric field-induced assembly of planar aggregates; the patterning of the electrolyte/silicon oxide/silicon interface to exert spatial control over the assembly process; and the real-time control of the assembly process via external illumination. The present invention provides a set of fundamental operations enabling interactive control over the creation and placement of planar arrays of several types of particles and biomolecules and the manipulation of array shape and size. The present invention enables sample preparation and handling for diagnostic assays and biochemical analysis in an array format, and the functional integration of these operations.

Abstract: A fractionating apparatus is used for fractionating sample into micro-structures different in size, and includes a fractionating unit formed with a fractionating passage; the fractionating passage is defined in a groove formed in a substrate of the fractionating unit, and pillar patches are formed in the groove at intervals wider than the gap among the pillar patches; while the sample is migrated through the fractionating passage, small-sized DNA molecules are trapped in the pillar patches, and large-sized DNA molecules are smoothly migrated through the wide intervals; this results in that the large-sized DNA molecules reaches the end of the fractionating passage faster than the small-sized DNA molecules without clogging.

Abstract: A method of separating components having a given negative or positive charge and contained in a sample is disclosed. The method involves, in one embodiment, loading a microchannel with a sample, placed between a trailing-edge electrolyte having a selected concentration of a titratable species, and a leading-edge electrolyte.

Abstract: A method and apparatus for fractionation of a mixture of particles and for particle analysis are provided, in which LEAPS (“Light-controlled Electrokinetic Assembly of Particles near Surfaces”) is used to fractionate and analyze a plurality of particles suspended in an interface between an electrode and an electrolyte solution. A mixture of particles are fractionated according to their relaxation frequencies, which in turn reflect differences in size or surface composition of the particles. Particles may also be analyzed to determine their physical and chemical properties based on particle relaxation frequency and maximal velocity.

Abstract: A method of separating components having a given negative or positive charge and contained in a sample is disclosed. The method involves, in one embodiment, loading a microchannel with a sample, placed between a trailing-edge electrolyte having a selected concentration of a titratable species, and a leading-edge electrolyte.

Abstract: The present invention relates a method of electrophoretic separation of protein and/or peptide components of a sample in a convection stabilised medium. More specifically, the method comprises the steps to contact the sample with the separation medium; to apply a voltage across said medium; and to observe the results by analysis of one or more sections of the separation medium. In the present method, a disulphide-comprising compound is added before or during the procedure to make an excess of reactive disulphide groups accessible to react with the cysteine groups of the proteins and/or peptides all through the separation procedure. The present invention also relates to electrophoretic separation media that comprises reactive disulphide groups, such as polyacrylamide gels, and the use of a solution that comprises reactive disulphide groups to pretreat an electrophoretic separation medium.

Abstract: A fluid circuit includes a membrane having a first side, a second side opposite the first side, and a pore extending from the first side to the second side. The circuit also includes a first channel containing fluid extending along the first side of the membrane and a second channel containing fluid extending along the second side of the membrane and crossing the first channel. The circuit also includes an electrical source in electrical communication with at least one of the first fluid and second fluid for selectively developing an electrical potential between fluid in the first channel and fluid in the second channel. This causes at least one component of fluid to pass through the pore in the membrane from one of the first channel and the second channel to the other of the first channel and the second channel.

Abstract: A medical diagnostic method and instrumentation system for analyzing noncovalently bonded agglomerated biological particles is described. The method and system comprises: a method of preparation for the biological particles; an electrospray generator; an alpha particle radiation source; a differential mobility analyzer; a particle counter; and data acquisition and analysis means. The medical device is useful for the assessment of human diseases, such as cardiac disease risk and hyperlipidemia, by rapid quantitative analysis of lipoprotein fraction densities. Initially, purification procedures are described to reduce an initial blood sample to an analytical input to the instrument. The measured sizes from the analytical sample are correlated with densities, resulting in a spectrum of lipoprotein densities. The lipoprotein density distribution can then be used to characterize cardiac and other lipid-related health risks.

Abstract: This invention provides methods for using liquid junction potentials to control the transport of charged particles in fluid streams that are in laminar flow within microfluidic channels. Applications of the methods of this invention include sample preconditioning (removal of interfering substances), electrophoretic separation (fractionation) of charged particles, enhanced or delayed mixing of charged particles across a fluid interface relative to diffusion only, focusing charged particles in a fluid stream in one or two dimensions, and concentration of charged reactants at a fluid interface.

Abstract: The present invention relates to an apparatus for monitoring the progress of membrane fouling that occurs on pores as well as on the surface of a membrane by means of variations of zeta potential (&zgr;) of a hollow-fiber membrane according to time passage of filtration of a suspension, wherein colloid particles, biopolymers and other inorganic particles are dispersed, and the method thereof. Moreover, the present invention also relates to a method to identify the effect of concentration polarization layer and cake layer which can vary according to the axial position of a hollow-fiber and the developing progress of a membrane fouling by measuring the position-dependent zeta potential of the hollow-fiber membrane.

Abstract: A method and apparatus for fractionation of a mixture of particles and for particle analysis are provided, in which LEAPS (“Light-controlled Electrokinetic Assembly of Particles near Surfaces”) is used to fractionate and analyze a plurality of particles suspended in an interface between an electrode and an electrolyte solution. A mixture of particles are fractionated according to their relaxation frequencies, which in turn reflect differences in size or surface composition of the particles. Particles may also be analyzed to determine their physical and chemical properties based on particle relaxation frequency and maximal velocity.

Abstract: A method of separating components having a given negative or positive charge and contained in a sample is disclosed. The method involves, in one embodiment, loading a microchannel with a sample, placed between a trailing-edge electrolyte having a selected concentration of a titratable species, and a leading-edge electrolyte.

Abstract: An apparatus for inducing movement of an electrolytic droplet includes: a housing having an internal volume filled with a liquid immiscible with an electrolytic droplet; a distribution plate positioned within the chamber having an aperture and dividing the housing into upper and lower chambers; a lower electrode positioned below the lower chamber and the aperture in the distribution plate and being separated from the lower chamber by an overlying hydrophobic insulative layer; an upper electrode located above the upper chamber and the aperture of the distribution plate and being separated from the upper chamber by an underlying hydrophobic insulative layer; and first, second and third voltage generators that are electrically connected to, respectively, the lower and upper electrodes and the distribution plate.

Abstract: A method of, and apparatus for, automatically determining an electric charge—related characteristic or derived parameter of particles in a dispersion or of a cell wall, comprises having a particle—containing dispersion provided in a cell. The dispersion is illuminated with light from a light source and detecting from a detection volume light scattered from the particles. An electric field is applied to the dispersion at a first frequency of change of direction of the electric field and an electric field is subsequently applied to the dispersion at a second frequency of change of direction of the electric field. First signals detected from the scattered light when the first frequency electric field is applied are used to provide first values related to the velocity distribution of the particles.

Abstract: A toner characterization cell used to determine characteristics of insoluble particles in a liquid medium. First and second electrode are spaced apart and an electric field is applied between the electrodes and a displacement current is measured. Optical density measuring devices measure the change in optical density in the cell adjacent each electrode. The characteristics are determined from the displacement current and the change in optical density. The characterizing feature may be particle mobility. The invention also relates to a method of determining the characteristics.

Abstract: The invention concerns electrophoresis and methods and electrolyte compositions for decoupling or isolating the dual functions of the electrolyte composition in order to increase separation selectivity or reduce electromigration dispersion, or both. An electrolyte composition is used in electrophoresis to separate a charged analyte having a mobility .mu..sub.a in an electric field. The composition includes a buffer system having an ionic component that controls the pH of the composition and mobility matching ions having a mobility .mu..sub.2 in the electric field, such that .mu..sub.a /.mu..sub.2 equals about one. Alternatively, the buffer system may maintain the composition's pH and a complexing agent may complex with the buffer system to alter the mobility .mu..sub.2 of an ionic component of the buffer system, such that .mu..sub.a /.mu..sub.2 equals about one. The pH of the composition is within a pH range selected based on the analyte to be separated, and .mu..sub.

Abstract: An ionic liquid-channel charge-coupled device that separates ions in a liquid sample according to ion mobility characteristics includes a channel having an inner wall that has a matrix liquid disposed within. An insulating material surrounds the channel, and an introduction element introduces a liquid sample into the channel. The sample is preferably a liquid solution that has at least one ionic specie present in the solution. The device further includes a gating element that establishes at least one charge packet in the channel in response to an externally applied input signal, and a transport element that induces the charge packet to migrate through the channel. The gate element can be a plurality of spaced-apart, electrically conductive, gate structures that are alternately disposable between a high voltage state and a low voltage state. The transport element further includes an application element that applies a variable voltage to the gating element.

Abstract: An electrophoresis device is disclosed which may be partially disassembled and sterilized in an autoclave. The device includes a base and support framework extending from the base. A separation column including a separation chamber having a pair of plates spaced from and positioned generally parallel to one another is supported from the framework. A pump is provided for pumping buffer solution through the separation chamber. A sample injection device is located near an inlet of the separation chamber and a collection assembly is located near the outlet of the separation chamber. An electrical compartment is supported by the framework and controls the pump, injection device and collection assembly and is removably located in the electrical compartment. The separation column plates are made of a heat resistant plastic.

Abstract: The present invention is a method and apparatus for further reducing the size of nanoparticles. Nanoparticles are defined as having an effective average particle size of less than about 400 nm. The present invention separates the nanoparticles further using electric fields.