Abstract: Electrokinetic devices having a computer for correcting for electrokinetic effects are provided. Methods of correcting for electrokinetic effects by establishing the velocity of reactants and products in a reaction in electrokinetic microfluidic devices are also provided. These microfluidic devices can have substrates with channels, depressions, and/or wells for moving, mixing and monitoring precise amounts of analyte fluids.

Abstract: The current invention provides a device, and a method for using the device, for ensuring that a capillary or wicking fill device is fully filled. In particular this invention is directed to, but not limited to, use with capillary or wicking action filled electrochemical sensors suitable for use in analyzing blood or interstitial fluids.

Abstract: Microanalytical systems based on a microfluidics/electrochemical detection scheme are described. Individual modules, such as microfabricated piezoelectrically actuated pumps and a microelectrochemical cell were integrated onto portable platforms. This allowed rapid change-out and repair of individual components by incorporating “plug and play” concepts now standard in PC's. Different integration schemes were used for construction of the microanalytical systems based on microfluidics/electrochemical detection. In one scheme, all individual modules were integrated in the surface of the standard microfluidic platform based on a plug-and-play design. Microelectrochemical flow cell which integrated three electrodes based on a wall-jet design was fabricated on polymer substrate. The microelectrochemical flow cell was then plugged directly into the microfluidic platform.

Abstract: A cell analysis and sorting apparatus is capable of monitoring over time the behavior of each cell in a large population of cells. The cell analysis and sorting apparatus contains individually addressable cell locations. Each location is capable of capturing and holding a single cell, and selectively releasing that cell from that particular location. In one aspect of the invention, the cells are captured and held in wells, and released using vapor bubbles as a means of cell actuation. In another aspect of the invention, the cells are captured, held and released using electric field traps.

Abstract: The present invention relates to a device and method for measuring the level of an oxidant or antioxidant analyte in a fluid sample. The device comprises a disposable electrochemical cell, such as a thin layer electrochemical cell, containing a reagent capable of undergoing a redox reaction with the analyte. When the device or method is to be used with slow-reacting analytes, heat may be applied to the sample by a resistive heating element in the device or by an exothermic material contained within the electrochemical cell. Application of heat will accelerate the rate of the redox reaction between the reagent and the analyte and thus facilitate the electrochemical measurement of slow-reacting analytes.

Abstract: According to an aspect of the invention, a cell for electrochemical analysis is provided, comprising a body having a chamber, and a pair of electrodes opposing each other within the camber comprising a electrically conductive rod extending through the body transverse to the longitudinal direction and removed within the capillary channel. According to a preferred embodiment, at least one reagent is provided within the capillary channel. The cell may be part of a plurality of such cells connected in seriatim.

Abstract: The present invention relates to an electrochemical sensor for a liquid sample. The sensor comprises a substrate (1) along which a liquid may travel by capillary action, said substrate being associated with an electrochemical detection arrangement (3) and a power source therefor, wherein the power source comprises at least one pair of electrodes (7, 8) of dissimilar material provided on the substrate and arranged such that liquid travel between the electrodes causes a current to be generated for operating the electrochemical detection arrangement.

Abstract: A sensor (1) for measuring O2 concentrations in liquids (2) has a working electrode (3), with a counterelectrode (4) and with a reference electrode (5), wherein the working electrode (3) and the counterelectrode (4) are in contact with the liquid (2). The reference electrode (5) is separated from the liquid (2) by a diaphragm (6). The reference electrode (5) measures a polarization voltage effectively acting at the working electrode (3) and is connected to a potentiostat regulating the potential between the working electrode (3) and the counterelectrode (4). The reference electrode (5), the working electrode (3) and the counterelectrode (4) are arranged coaxially to one another, wherein the working electrode (3) and the counterelectrode (4) are arranged around the reference electrode (5).

Abstract: An apparatus and method are disclosed for in vitro transformation of living cells. The apparatus, which is formed as a microelectromechanical device by surface micromachining, can be used to temporarily disrupt the cell walls or membrane of host cells one at a time so that a particular substance (e.g. a molecular tag, nucleic acid, bacteria, virus etc.) can be introduced into the cell. Disruption of the integrity of the host cells (i.e. poration) can be performed mechanically or electrically, or by both while the host cells are contained within a flow channel. Mechanical poration is possible using a moveable member which has a pointed or serrated edge and which is driven by an electrostatic actuator to abrade, impact or penetrate the host cell. Electroporation is produced by generating a relatively high electric field across the host cell when the host cell is located in the flow channel between a pair of electrodes having a voltage applied therebetween.

Abstract: A self-cleaning oxidation-reduction potential (“ORP”) probe system includes an ORP electrode (11), a flow cell (12) surrounding the ORP electrode, and a plurality of cleaning beads (17) contained in the flow cell in a manner in which they are free to contact the ORP electrode when fluid is passed through the flow cell. The self-cleaning probe system may also or alternatively include a pH probe electrode, or another fluid-testing probe, in the flow cell.

Abstract: A sensor strip comprises an electrode substrate, an electrode set, on the electrode substrate, and microspheres. The sensor strip allows for a smaller sample volume and maintain a more uniform flow profile through the sample channel.

Abstract: An apparatus for determining a component present in a liquid sample in free state or bound to constituents, preferably for measuring the SO2 content in the sample, has a locating space for the liquid sample, a sensor preferably responding selectively to the component, preferably based on an electrochemical cell, and a gas piping system via which a carrier gas can be passed from the locating space through the sensor (FIG. 1).

Abstract: Electrokinetic devices having a computer for correcting for electrokinetic effects are provided. Methods of correcting for electrokinetic effects by establishing the velocity of reactants and products in a reaction in electrokinetic microfluidic devices are also provided. These microfluidic devices can have substrates with channels, depressions, and/or wells for moving, mixing and monitoring precise amounts of analyte fluids.

Abstract: The invention relates to a sensor (1) for helium or hydrogen with a vacuum-tight housing (2), wherein a gas consuming cold cathode array (3, 4) is arranged, in addition to a selectively active passage (9) for the gas to be detected. According to the invention, in order to improve the properties of said sensor, the housing (2) is made of glass, components of the gas passage (9) include a membrane (18) made of a silicon material having the desired selective qualities, in addition to a silicon plate (19) which supports the membrane (18) and is provided with a plurality of openings (21) and a heating element (24). The housing (2) and the selectively active gas passage (9) are joined together without polymer and elastomer.

Abstract: A gas sensor for measuring an amount of a measurement gas component, including a solid electrolyte having an internal space, a gas-introducing port for introducing measurement gas from an external space into the internal space, diffusion rate-determining means between the internal space and the gas-introducing port, and inner and outer pumping electrodes for pumping-processing oxygen contained in the measurement gas. The diffusion rate-determining means includes slits each having, when viewed in a plane substantially perpendicular to a longitudinal extension axis thereof, two dimensions, with at least one dimension of each slit being not more than 10 microns.

Abstract: Disclosed is a biopolymer (DNA) detector capable of performing overall analysis including an unreacted sample without needing any complex work such as washing or the like. A DNA probe 66 is fixed to an electrode plate 22, and the electrode plate 22 is displaced by applying a DC voltage between electrode plates 22 and 23. Thus, sample DNA 63 to be detected can be separated. It becomes possible to obtain a clearer result by performing analysis based on a ratio of an entire reaction system.

Abstract: An electrochemical sensor for detection of a gas in an atmosphere containing the gas. The sensor has a housing having an electrochemical gas sensor with an electrolyte and at least two electrodes, one electrode being a gas sensing electrode. The housing has an orifice between the sensing electrode and the atmosphere for transmission of gas from the atmosphere to the sensing electrode, the orifice being protected by a hydrophobic membrane, and connected to at least two radial channels extending from the orifice. Each of the radial channels is connected to a common channel, such that gas communication from the atmosphere through the orifice to the sensing electrode is through the common channel and the radial channels, in addition to the covering membrane if the membrane is gas permeable.

Abstract: The present invention relates to a filtration-detection device for detecting or quantifying an analyte in a test sample including a filtration device having a first binding material immobilized thereto, wherein the first binding material is capable of binding to a portion of the analyte, and a detection assembly positioned relative to the filtration device to detect or quantify analyte bound to the first binding material. The present invention also relates to methods of using the filtration-detection device.

Abstract: The invention concerns a composition for use in a process for separating the constituents of a sample by electrophoresis on an electrophoresis support, comprising one or more ionic compounds which, on applying an electric field to an electrophoresis support having negative surface charges, causes hydration of the zone for loading the sample to be separated when said zone carries a compression mark resulting from loading the sample.

Abstract: A sensor having a conductive protective sheath, an internal sensor element and a conductive end cap. The conductive end cap is connected to the distal end of the conductive protective sheath and is in contact with the internal sensor element. The conductive protective sheath has a plurality of apertures symmetrically arranged to prevent fluid flow in a straight direction of a sample fluid through the conductive protective sheath. A sensor having a conductive protective sheath, an internal sensor element and a conductive end cap. The conductive end cap is connected to the distal end of the conductive protective sheath. The conductive end cap one or more contact areas from the group including a side contact area, an upper contact area and an internal indentation contact area. The internal sensor is in contact with at least one of the contact areas of the conductive end cap.

Abstract: The invention provides a method for determining the concentration of an analyte in a sample comprising the steps of heating the sample and measuring the concentration of the analyte or the concentration of a species representative thereof in the sample at a predetermined point on a reaction profile by means that are substantially independent of temperature. Also provided is an electrochemical cell comprising a spacer pierced by an aperture which defines a cell wall, a first metal electrode on one side of the spacer extending over one side of the aperture, a second metal electrode on the other side of the spacer extending over the side of the aperture opposite the first electrode, means for admitting a sample to the cell volume defined between the electrodes and the cell wall, and means for heating a sample contained within the cell.

Abstract: The analysis flow cell provided with a thin-film or thick-film sensor is designed so that the input and outlet for the fluid to be investigated are on opposite sides of the sensor layer and so that there is at least one passage (24) transverse to the sensor film, which can be in the sensor film or beside it in a layer of carrier. The sensor can be a biosensor, in which a thin layer of platinum, gold, or graphite is coated with a biosensor material.

Abstract: An agitated flow cell had a micro/miniature vibrator device such as pager motor to agitate the flow cell and its associated sensor to bring fresh analyte to the sensor surface without the need for microfluidic channels, pumps or valves. The agitated flow cell improves the confidence measure of a given sample reading by directing the flow of sample to the sensor/sample interface in a substantially shorter period of time than that required by flow cells that rely on diffusion of analyte molecules through the liquid depletion region in order to bring the sample reliably in contact with the sensor's biosensing film.

Abstract: A system and method for rapid hydration and reduced out-of-warm-up baseline drift for chemical, electrochemical and enzyme sensors.

Abstract: Disclosed is an electrochemical sensor for detecting the concentration of an analyte such as glucose in a fluid test sample. The sensor involves a base as flow path for the fluid test sample having a working and counter electrode on its surface. The base is mated with a cover to form a capillary space to capture the fluid and the counter electrode has a sub-element located upstream in the flow path. When there is detected electrical communication only between the sub-element and the working electrode the meter, with which the sensor is in electrical communication senses that the capillary space has not completely filled with test fluid.

Abstract: Electrokinetic devices having a computer for correcting for electrokinetic effects are provided. Methods of correcting for electrokinetic effects by establishing the velocity of reactants and products in a reaction in electrokinetic microfluidic devices are also provided. These microfluidic devices can have substrates with channels, depressions, and/or wells for moving, mixing and monitoring precise amounts of analyte fluids.

Abstract: A nanostructure based material is capable of accepting-and reacting with an alkali metal such as lithium. The material exhibits a reversible capacity ranging from at least approximately 900 mAh/g-1,500 mAh/g. The high capacity of the material makes it attractive for a number of applications, such as a battery electrode material.

Abstract: The present invention relates to a biosensor. The biosensor includes a support substrate having first and second ends, electrodes positioned on the support substrate, the electrodes cooperating with one another to define electrode arrays situated adjacent to the first end, a spacer substrate positioned on the support substrate, and a cover positioned on the spacer substrate. The cover cooperates with the support substrate to define a channel. The channel includes an inlet adjacent to the first end and opposite ends. Each electrode array is positioned in the channel adjacent to one of the ends.

Abstract: In a differential condition, an electrophoresis system antisynchronously drives a longitudinally-separated pair of contactless drive electrodes, both of which are coupled to a detection electrode through a separation channel. In this condition, the system provides a series of peaks readout in ITP-separation mode. In a direct condition, the system antisynchronously drives a pair of drive electrodes, only one of which is coupled to the detection electrode through the channel; the other is coupled to the detection electrode but not though the channel. In this condition, the system provides a series of peaks readout in CZE mode. In either case, the antisynchronous drive enhances the detection signal by canceling at the detection electrode signal components associated with the AC drive source. Similar advantages are achieved for a capillary differential electrophoresis system and for a planar direct electrophoresis system.

Abstract: A medical diagnostic device for measuring an analyte concentration in a sample of a biological fluid includes a capillary flow channel in the device to convey the sample from an inlet to a second region. The flow channel has a capillary dimension in at least one direction. A stop junction in the flow channel has a boundary region that has a dimension that is greater in that direction and forms an angle that points toward the sample inlet.

Abstract: A nanostructure based material is capable of accepting and reacting with an alkali metal such as lithium. The material exhibits a reversible capacity ranging from at least approximately 900 mAh/g-1,500 mAh/g. The high capacity of the material makes it attractive for a number of applications, such as a battery electrode material.

Abstract: A disposable receptacle unit for solutions is described, in particular for solutions used in calibrating sensors for measurement of physiologically relevant parameters. The receptacle is a disposable blister pack for a single use that includes several chambers to hold solutions. Each chamber is connected to a sample channel by an outlet channel sealed by a sealing element. The sensors for measurement of physiological parameters are preferably part of the receptacle unit. To calibrate the sensors, the calibration solutions in the chambers are metered into the sample channel after opening the corresponding sealing elements. After the treatment, the receptacle unit is discarded together with the sensors.

Abstract: A biosensor is provided that includes first and second plate elements, wherein each plate elements has first and second ends and first and second lateral borders. In addition, the biosensor includes a spacer positioned to lie between the first and second plate elements so that at least a portion of the first and second plate elements cooperate with one another to form opposite walls of a capillary space. Further, the first ends and at least a portion of the lateral borders define a fluid sample-receiving portion in communication with the capillary space. Electrodes are positioned in the capillary space of the biosensor.

Abstract: An oxygen monitor for a smokestack installation. The oxygen monitor includes a probe assembly mounted to the smokestack, a sensing assembly mounted to the probe assembly, and a monitor cabinet electrically connected to the sensing assembly. The probe assembly has an intake tube within an exhaust tube. Because the intake tube mouth is smaller than the effective exhaust tube mouth, the pressure reduction effect due to fluid travelling past the exhaust tube is greater than at the intake tube mouth, so fluid such as exhaust gasses tends to be drawn into the intake tube and towards an oxygen sensor. The fluid travels past the oxygen sensor and exits the probe assembly through the exhaust tube and its exhaust tube mouth, back into the smokestack. In addition, the hot oxygen sensor heats the fluid, causing it to rise into the exhaust tube and exit through its mouth. These two effects cause a self-circulation of the fluid being monitored for oxygen content, and eliminate the need for a separate fluid pump.

Abstract: A biosensor is provided in accordance with this invention. The biosensor includes a bottom section with an edge and a flange extending from the edge, a top section supported on the bottom section and having an edge and flange extending from the edge in alignment with the flange of the bottom section. The flanges of the top and bottom sections cooperate to form a capillary channel, and first and second electrodes. Additionally, the first electrode is positioned on the flange of the bottom section in the capillary channel and the second electrode is positioned on the flange of the top section in the capillary channel.

Abstract: Histamine may be quantitatively measured by performing the following steps. First, an oocyte that expresses histamine receptors is held in a recess formed at the bottom of a vessel. Then, first and second electrodes are inserted into the oocyte. Subsequently, the membrane potential of the oocyte is measured by using the first electrode to stabilize this membrane potential at a predetermined level by driving a current through the second electrode using circuitry for clamping the membrane potential of the oocyte. A sample is then infused into a fine reacting tube having an antigen immobilized on its inner surface together with some buffer solution to promote a histamine releasing reaction. The solution containing histamines that is released in the fine reacting tube is transferred to the vessel to make contact with the oocyte in the vessel.

Abstract: The present invention is drawn generally to an improved electrochemical sensor. The reference cell within the sensor can be a salt bridge comprising at least two chambers for containing an electrolyte fluid, preferably containing a semipermeable plug impregnated with an electrolyte, an essentially fluid impermeable plug for separating the at least two chambers, and a narrow opening through the plug providing a non-axial flow path for ionic communication between the at least two chambers when the electrolyte fluid is present.

Abstract: According to an aspect of the invention a biosensor apparatus is provided, comprising a base, electrodes positioned on the base, a cover including ports, a plate positioned on the base and including apertures in communication with at least one of the electrodes, a cover including ports in communication with the plate and offset from the apertures, and at least one reagent positioned between the plate and the cover. According to a preferred embodiment the plate includes microstructures extending into the ports of the cover.

Abstract: A modular, in particular multidimensional system for the reagent-free, continuous detection of a substance is disclosed. The system is characterized by the presence of at least two measurements modules of preferably different types. The modules are robust and designed for a long-time operation. They have an exchangeable or replaceable selective layer structure. The system may also include appropriate modules for amperometry and optical sensors.

Abstract: We have performed separation of bacterial and cancer cells from peripheral human blood in microfabricated electronic chips by dielectrophoresis. The isolated cells were examined by staining the nuclei with fluorescent dye followed by laser induced fluorescence imaging. We have also released DNA and RNA from the isolated cells electronically and detected specific marker sequences by DNA amplification followed by electronic hybridization to immobilized capture probes. Efforts towards the construction of a “laboratory-on-a-chip” system are presented which involves the selection of DNA probes, dyes, reagents and prototyping of the fully integrated portable instrument.

Abstract: A water quality meter is composed of a plurality of analyzing units for analyzing water samples introduced from a water distribution pipe, each analyzing unit including a reagent mixing cell and a measuring cell, and a liquid introducing unit integrated with the analyzing units, which is composed of a single member in which a plurality of fluid flows paths for feeding various types of liquid including the water sample into the analyzing unit are formed. Furthermore, the cells and the plurality of three-dimensional fluid flow paths formed in the single member are fabricated by a micro-fabrication technique using photo-curing resin. In one embodiment, a photometer is situated in the flow path in at least one analyzing unit for measuring absorbency of the liquid. In another embodiment, a pair of electrodes, for measuring electric conductivity or pH, is disposed in a measurement flow path in at least one of the analyzing units.

Abstract: Arrangement and method for detecting the end of life of an aqueous bath utilized in semiconductor processing, the bath containing water, an amount of hydrogen peroxide and an amount of a predetermined chemical species, which is either an acid or a base, in accordance with the following steps: adding a predetermined additional amount of the hydrogen peroxide and/or the predetermined chemical species at predetermined time intervals, measuring at least one parameter of the aqueous bath, thereby obtaining a measured parameter value, the at least one parameter being selected from a set of parameters including bath pH and bath conductivity; reading a predicted value of said at least one parameter from a memory storing a curve of predicted values of said at least one parameter as a function of time, said curve depending on said predetermined additional amount of said hydrogen peroxide and/or said predetermined chemical species, and depending on said predetermined time intervals; establishing the end of life of said

Abstract: An electrochemical measuring device comprises an essentially planar sensor substrate with at least one electrochemical sensor, and a cover part in which a tunnel-shaped measuring channel is formed. At least one guiding groove is provided in parallel with the measuring channel. A sealing element which is positioned between the sensor substrate and the cover part to seal the measuring channel is provided with guiding bodies along its length, at least one of which guiding bodies projects into the guiding groove of the cover part. The sealing element is provided with narrow sealing lips bounding the measuring channel. Each short side of the sealing element has a guiding body projecting into recesses in the sensor substrate. The guiding bodies are disposed on that side of a sealing plane defined by the sealing lips, which faces away from the cover part.

Abstract: This invention relates to a microfabricated capillary electrophoresis chip for detecting multiple redox-active labels simultaneously using a matrix coding scheme and to a method of selectively labeling analytes for simultaneous electrochemical detection of multiple label-analyte conjugates after electrophoretic or chromatographic separation.

Abstract: An analyzer for continuously measuring the H2S content of a gas stream which utilizes a drying module for drying the gas, a compressor for compressing the gas, a means for diluting the compressed sample and an electrical chemical sensor. The invention is also a device for regulating the flow rate of air to a H2S oxidation system which utilizes the analyzer to control the ratio of air to H2S stream entering the process.

Abstract: The unique cell frame of the present invention comprises an integral protector portion. This protector portion comprises a rigid or flexible lip on the membrane side of the cell frame. In an assembled cell stack, the membrane assembly is disposed between two cell frames on the side of the cell frames having the protector portion. Screen assemblies are disposed on the opposite side of the cell frame such that the screen assemblies rest on the protector portion, within the cell frame. The protector portion prevents the edge of the screen assemblies from pinching, cutting, or otherwise damaging the membrane.

Abstract: Histamine may be quantitatively measured by performing the following steps. First, an oocyte that expresses histamine receptors is held in a recess formed at the bottom of a vessel. Then, first and second electrodes are inserted into the oocyte. Subsequently, the membrane potential of the oocyte is measured by using the first electrode to stabilize this membrane potential at a predetermined level by driving a current through the second electrode using circuitry for clamping the membrane potential of the oocyte. A sample is then infused into a fine reacting tube having an antigen immobilized on its inner surface together with some buffer solution to promote a histamine releasing reaction. The solution containing histamines that is released in the fine reacting tube is transferred to the vessel to make contact with the oocyte in the vessel.

Abstract: Histamine may be quantitatively measured by performing the following steps. First, an oocyte that expresses histamine receptors is held in a recess formed at the bottom of a vessel. Then, first and second electrodes are inserted into the oocyte. Subsequently, the membrane potential of the oocyte is measured by using the first electrode to stabilize this membrane potential at a predetermined level by driving a current through the second electrode using circuitry for clamping the membrane potential of the oocyte. A sample is then infused into a fine reacting tube having an antigen immobilized on its inner surface together with some buffer solution to promote a histamine releasing reaction. The solution containing histamines that is released in the fine reacting tube is transferred to the vessel to make contact with the oocyte in the vessel.

Abstract: A nanostructure based material is capable of accepting and reacting with an alkali metal such as lithium. The material exhibits a reversible capacity ranging from at least approximately 900 mAh/g-1,500 mAh/g. The high capacity of the material makes it attractive for a number of applications, such as a battery electrode material.

Abstract: Histamine may be quantitatively measured by performing the following steps. First, an oocyte that expresses histamine receptors is held in a recess formed at the bottom of a vessel. Then, first and second electrodes are inserted into the oocyte. Subsequently, the membrane potential of the oocyte is measured by using the first electrode to stabilize this membrane potential at a predetermined level by driving a current through the second electrode using circuitry for clamping the membrane potential of the oocyte. A sample is then infused into a fine reacting tube having an antigen immobilized on its inner surface together with some buffer solution to promote a histamine releasing reaction. The solution containing histamines that is released in the fine reacting tube is transferred to the vessel to make contact with the oocyte in the vessel.