Abstract: Chemical sensors for detecting the activity of a molecule or analyte of interest is provided. The chemical sensors comprise and array or plurality of chemically-sensitive resistors that are capable of interacting with the molecule of interest, wherein the interaction provides a resistance fingerprint. The fingerprint can be associated with a library of similar molecules of interest to determine the molecule's activity.

Abstract: Apparatus for eliminating halide ions such as chloride ions from aqueous solutions having a hollow cylindrical sample holding chamber (2), the front end of which has an orifice (3) and in the vicinity of which is disposed a filter plate (4) that extends over the cross section of the sample holding chamber (2) and is liquid-permeable and essentially impermeable for solids and is inserted in a fixed manner into the hollow cylinder; a plunger (6) which can move to and fro in the sample holding chamber (2) and has a plunger stem (7) attached thereto engages in the open rear end (5) of the sample holding chamber, and, in the sample holding chamber (2) between the filter plate (4) and the plunger (6) is disposed a freely movable bed (7) of an adsorbent reacting with halide ions and forming a sparingly soluble compound, which bed fills a part of the sample holding chamber (2). The adsorbent is preferably charged with silver nitrate as compound reactive with halide ions.

Abstract: An amperometric bromine control system accurately maintains a desired concentration of bromine within a home spa or in other water features. The control system employs amperometric sensing to measure the bromine concentration in the spa water and uses this measurement to control the electrochemical production of bromine through the oxidation of aqueous bromide. The level of bromide in the spa water desirably is greater than 50 ppm in order to obtain a linear relationship between the current level sensed through the amperometric measurement and the concentration level of bromine in the water. In this manner, the control system can accurately measure the bromine concentration in the spa water and precisely maintain the bromine concentration within a desired range between about 2 ppm and 6 ppm.

Abstract: An implantable enzyme-based monitoring system suitable for long term in vivo use to measure the concentration of prescribed substances such as glucose is provided. In one embodiment, the implantable enzyme-based monitoring system includes at least one sensor assembly, an outer membrane surrounding the sensor assembly and having a window therein, and a polymeric window cover affixed to the outer membrane and covering the window. Preferably, the outer membrane of the monitoring system is silicone and the window cover is a polymer of 2-hydroxyethyl methacrylate (HEMA), N,N,-dimethylaminoethyl methacrylate (DMAEMA) and methacrylic acid (MA). Also provided herein is an implantable enzyme-based monitoring system having at least one sensor assembly, an outer membrane surrounding the sensor assembly and a coating affixed to the exterior surface of the outer membrane, wherein the coating resists blood coagulation and protein binding to the exterior surface of the outer membrane.

Abstract: The invention is a method for the formation and analysis of novel miniature deposition domains. These deposition domains are placed on a surface to form a molecular array. The molecular array is scanned with an AFM to analyze molecular recognition events and the effect of introduced agents on defined molecular interactions. This approach can be carried out in a high throughput format, allowing rapid screening of thousands of molecular species in a solid state array. The procedures described here have the added benefit of allowing the measurement of changes in molecular binding events resulting from changes in the analysis environment or introduction of additional effector molecules to the assay system. The processes described herein are extremely useful in the search for compounds such as new drugs for treatment of undesirable physiological conditions.

Abstract: A thick film electrochemical micro-sensor apparatus for detection and quantification of trace metal ions in water, comprising a substrate to which is applied an arrangement of electrodes comprising at least one of a first type of working electrode, at least one of a second type of working electrode, a counter electrode, a reference electrode, and optionally pH and temperature detectors. The apparatus is especially useful for detection and quantification of trace metal ions in water and effluent. A method of detecting and quantifying trace metal ions using the electrochemical micro-sensor apparatus is also described comprising contacting the water or effluent with the sensor of the present invention, applying a voltage selected for the trace metal ion to be detected, measuring the current output of the micro-sensor, determining if the current output indicates the presence of the trace metal ion, and generating a signal.

Abstract: In order to reduce a treating time for distributing micro-substances, for example, particles, molecules and the like such as cells, organelles, proteins, and nucleic acids, there is provided a microchip for aqueous distribution comprising a micro channel having a predetermined shape, which is defined on a flat plate substrate; and a plurality of branched channels, each of which has a predetermined shape and is defined on the substrate, besides these branched channels are linked to only either end of the micro channel.

Abstract: A gas sensor assembly is provided with a non-conductive housing portion and a plurality of conductive housing portions, each of which are conductively separated from each other, and the conductive housing portions are composed of a conductive plastic material. A gas-sensing agent is disposed in a receptacle formed in the housing, and a plurality of electrodes are disposed in conductive contact with the gas-sensing agent. The gas sensor has an electrode support sheet with a plurality of electrodes formed thereon, and a seal is formed between the electrode support sheet and the housing, the seal being formed by the sealing of a portion of one of the electrodes to a portion of the housing.

Abstract: A sensor utilizing a non-leachable or diffusible redox mediator is described. The sensor includes a sample chamber to hold a sample in electrolytic contact with a working electrode, and in at least some instances, the sensor also contains a non-leachable or a diffusible second electron transfer agent. The sensor and/or the methods used produce a sensor signal in response to the analyte that can be distinguished from a background signal caused by the mediator. The invention can be used to determine the concentration of a biomolecule, such as glucose or lactate, in a biological fluid, such as blood or serum, using techniques such as coulometry, amperometry, and potentiometry. An enzyme capable of catalyzing the electrooxidation or electroreduction of the biomolecule is typically provided as a second electron transfer agent.

Abstract: An apparatus is disclosed for electrolytic desilvering of photographic processing solutions, more particularly fixing solutions or bleach-fixing solutions, comprising an electrolysis unit equiped with a monitoring system comprising a cathode, an anode and a reference electrode, characterized in that said reference electrode is a pH sensitive electrode. The desilvering is preferably performed under potentiostatic conditions. Whe using a pH sensitive reference electrode the cathodic plating potential is automatically corrected for pH changes. A preferred pH sensitive electrode is a glass electrode.

Abstract: A method and device for detection and quantification of biologically significant analytes in a liquid sample is described. The method includes contacting a volume of a liquid sample with predetermined amounts of at least a first and second redox reversible species having redox potentials differing by at least 50 millivolts. At least one of the redox reversible species comprises a liquid sample diffusible conjugate of a ligand analog of an analyte in the liquid sample and a redox reversible label. A predetermined amount of at least one specific binding partner for each analyte to be measured is combined with the sample and current flow is measured at first and second anodic and cathodic potentials and correlated with current flows for known concentrations of the respective diffusible redox reversible species. Diagnostic devices and kits, including such devices and the specified specific binding partner(s) and redox reversible species are also described.

Abstract: An electrode design is provided for corrosion monitoring using electrochemical noise measurements. Electrochemical probes are used for sensing electrochemical noise voltage values and electrochemical noise current values. The electrochemical probes include a pair of working electrodes formed of the same material of the monitored metal pipes or storage vessels and a reference electrode formed of a corrosion resistant material. Each of the pair of working electrodes has a defined surface roughness. One of the pair of working electrodes has reduced roughness, whereby sensitivity to sustained localized pitting corrosion is increased in the working electrode with reduced roughness. By reducing the surface roughness of one of the pair of working electrodes, increased sensitivity to sustained localized pitting corrosion is provided while the current noise can be used to accurately measure the general corrosion rate on the unpolished electrode.

Abstract: A detector assembly for detecting a plurality of different properties at the same location at the same time is provided by integrating onto a single semiconductor substrate a first detector unit for measuring a first property and a second detector unit for measuring a second property. The first and second detector units can share, for example, a common element, such as a sensor device that can provide electrical output signals representative of, respectively, the first property and the second property. The common element can include a diaphragm with a pyroelectric element to provide a measurement of temperature and pressure.

Abstract: The present invention provides a combinatorial approach for preparing arrays of chemically sensitive polymer-based sensors which are capable of detecting the presence of a chemical analyte in a fluid in contact therewith. The described methods and devices comprise combining varying ratios of at least first and second organic materials which, when combined, form a polymer or polymer blend that is capable of absorbing a chemical analyte, thereby providing a detectable response. The detectable response of the sensors prepared by this method is not linearly related to the mole fraction of at least one of the polymer-based components of the sensors, thereby making arrays of these sensors useful for a variety of sensing tasks.

Abstract: An apparatus and a method of characterising liquids employ liquid sensors of different types of technology, in order to generate characterisation data from the whole of the output signals originating from these sensors when they are soaked in a sample of the liquid. The set of sensors may comprise: lipid sensors, quartz microbalances, ion-selective electrodes, biosensors, chemical microelectrodes or even, in certain particular applications, fiber optic based-sensors. The output signals originating from the different sensors are normalized with respect to values which are determined in a prior standardization operation during which the sensors were soaked in at least one sample reference liquid.

Abstract: A method for determining the concentration of a reduced (or oxidised) form of a redox species in an electrochemical cell of the kind comprising a working electrode and a counter electrode spaced from the working electrode by a predetermined distance, said method comprising the steps of: (1) applying an electric potential difference between the electrodes; (2) selecting the potential of the working electrode such that the rate of electro-oxidation of the reduced form (or electro-reduction of the oxidised form) of the species is diffusion controlled, (3) selecting the spacing between the working electrode and the counter electrode so that reaction products from the counter electrode arrive at the working electrode; (4) determining current as a function of time after application of the potential and prior to achievement of a steady state; (5) estimating the magnitude of the steady state current, and (6) obtaining from the change in current with time and the magnitude of the steady state current, a value indicati

Abstract: An electrochemical cell sensing circuit for an electrochemical cell having a working electrode, a counter electrode and a reference electrode in an electrolyte, which in use, when a gas to be analysed is introduced into the cell, generating a current between the counter electrode and the working electrode, and a potential at a position in the electrolyte is sensed by the reference electrode.

Abstract: An improved biologic electrode array and methods for manufacturing and using the same. In one aspect, a matrix of electrodes each coupled to a respective sample-and-hold circuit is provided. The electrodes and sample-and-hold circuits are integral and form an array within a single semiconductor chip, such that each sample-and-hold circuit may be loaded with a predefined voltage provided by a single, time-shared digital-to-analog converter (DAC). Further, all of the sample-and-hold circuits may be accessed through a multiplexer which may be scanned through some or all of the electrode locations. Each sample-and-hold circuit may comprise a capacitor and one or more transistor switches, the switch(es), when closed, providing electrical communication between the capacitor and a source line formed in the matrix.

Abstract: A disposable electrode strip for testing a fluid sample including a laminated strip with a first and second end, a vent, an open path for receiving a fluid sample of less than one microliter beginning from the first end and connecting to the vent, a working electrode, a reference electrode and a pseudo-working electrode embedded in the laminated strip within the open path and proximate to the first end, a reagent matrix coextensive within the open path and covering the three electrodes, and conductive contacts located at the second end of the laminated strip.

Abstract: A scanning probe microscope is provided for measuring at least one characteristic of a surface, the microscope including a force sensing probe which is responsive to the at least one characteristic of the surface, an oscillator which moves the position of the probe relative to the surface, a voltage source for establishing an electrical potential between the force sensing probe and the surface, and a detector which detects the oscillating component of the electrical current flow into or out of the probe as a measure of the at least one characteristic of the surface. The microscope can be operated to simultaneously acquire both electrical and topographical information from a surface of a substrate.

Abstract: A buoyant water conditioner has a housing with an upper surface and an apertured chamber for receiving a chlorination agent. Three separate measurement systems are carried by the housing: a water temperature system, a pH level system, and a chlorine concentration system. Each system has a sensor for measuring the respective water parameter, a display for displaying the measured value, and a processor for converting the sensor signals to display driving signals. Each system is powered by a solar cell battery or a chemical battery.

Abstract: The present invention discloses a method of forming a metal layer by thermal evaporation or RF reactive sputtering in order to fabricate a light shielding layer for an ion sensitive field effect transistor. The multi-layered construction of the ion sensitive field effect transistor with a metal thin film as a light shielding layer is SnO2/metal/SiO2 or SnO2/metal/Si3N4/SiO2, and is able to lower the effect of light successfully.

Abstract: A device for automatically measuring a concentration of a developing agent in a developing bath includes a voltage generator capable of generating at least one voltage ramp provided to feed a three-electrode cell; a potentiostat provided to maintain a constant potential difference between two electrodes; a peak detector provided to identify the maximum current flowing in the three-electrode cell that corresponds to the developing agent concentration; and a display unit provided to show the maximum current.

Abstract: A chemical sensor (1) for selectively detecting an analyte in a solution as described. The sensor comprises a flow-through chamber (2), a selective membrane (3), a transducer means (4), an inlet (5) for a liquid flow containing a recognition element, and an outlet (6). There is also described a method of selectively detecting an analyte in a solution, wherein a recognition element is contacted with the solution containing the analyte via a selective membrane, said contact resulting in a response detectable by transducer means. The recognition element is injected into a flow, the flow is passed into a flow-through chamber comprising a transducer means and the selective membrane, where it is contacted with the analyte passing from the solution outside the selective membrane, whereby the recognition element and the analyte interact to provide a signal which is detected by the transducer means.

Abstract: A sulfur dioxide gas sensor having a high selectivity of SO2 gas, and an operability at a high temperature which comprises: a solid electrolyte having oxygen ion conductivity; a detecting electrode for measuring sulfur dioxide gas, electrically connected to at least a part of a surface of the solid electrolyte and containing glass and either gold or a gold alloy; and a basic electrode for measuring sulfur dioxide gas, electrically connected to at least a part of a surface of the solid electrolyte and containing Pt.

Abstract: An electrode and method of preparing an electrode by electropolymerizing a film on the conductive working surface of an electrode. The electrode is modified by reductive electropolymerization of a thin film of poly[Ru(vbpy)32+] or poly[Ru(vbpy)32+/vba] (vbpy=4-vinyl-4′methyl-2,2′-bipyridine and vba=p-vinylbenzoic acid) and the electrode is used for the electrochemical detection of aqueous GMP, poly[G], and surface immobilized single-stranded DNA probes. The film is formed from a co-polymer of a mediator such as Ru(vbpy)32+ and a functionalized moiety having a carboxylate group such as p-vinylbenzoic acid. A DNA probe is attached covalently to the carboxylate group via a carbodiimide reaction followed by amidation of an amino-linked single-stranded DNA.

Abstract: An electrochemical gas sensor including a sensor body having a cavity, an electrolyte in the cavity, an auxiliary electrode in contact with the electrolyte, a sensing electrode in contact with the electrolyte, and a blocking electrode in contact with the electrolyte. At least a portion of the blocking electrode is positioned intermediate the auxiliary electrode and the sensing electrode, and the blocking electrode reduces electroactive materials within the electrolyte. Also disclosed is a method for sensing a partial pressure of a target gas in a sample gas, the method including introducing the sample gas into a gas sensor, applying different potentials to the auxiliary electrode, sensing electrode and blocking electrode, reducing electroactive materials present in the electrolyte to prevent the electroactive materials from contacting the sensing electrode, and outputting an electrical signal from the gas sensor representative of the target gas partial pressure.

Abstract: A biosensor has a lipid membrane (7) containing gated ion channels sensitive to the presence or otherwise of an analyte molecule in a sample applied, in use, to a first side of the lipid membrane (7). The lipid membrane (7) is disposed between a pair of electrodes (1, 2) in which a first layer of porous gel (4) is applied to the first side of the lipid membrane (7).

Abstract: An electronic sensor is described that includes a sample receptacle and a data storage device. The data storage device is powered by a pair of half cells on the sensor. The half cells contain ion solutions that are also used to calibrate the sensor. As the sensor is placed within a sensor data reader, the data stored on the data storage device is transferred to the reader along with measurements of the voltage potential between the half cells. The reader thereafter calculates a calibration slope curve for the sensor. The calibration slope curve is then used to determine the exact ion concentration of any sample that is placed in the sample receptacle.

Abstract: The present invention is a sensor formed over a subminiature through hole. Because of the small diameter of the through hole, the material that fills the through hole and the through hole itself have an essentially negligible effect on the sensor. Only a small amount of conductive material which fills each through hole is in contact with each associated electrode. Therefore, the purity of the electrode is not significantly altered by the conductive material coupled to the electrode. A relatively large number of sensors can be formed on the surface of the substrate within a relatively small fluid flowcell. Thus, more information can be attained using less blood. The sensors of the present invention are preferably disposed on an alumina substrate which is essentially impervious to aqueous electrolytes and blood over long periods of storage in potentially corrosive environments.

Abstract: This invention relates to a low impedance cell potential measuring electrode assembly typically having a number of microelectrodes on an insulating substrate and having a wall enclosing the region including the microelectrodes. The device is capable of measuring electrophysiological activities of a monitored sample using the microelectrodes while cultivating those cells or tissues in the in the region of the microelectrodes. The invention utilizes independent reference electrodes to lower the impedance of the overall system and to therefore lower the noise often inherent in the measured data. Optimally the microelectrodes are enclosed by a physical wall used for controlling the atmosphere around the monitored sample.

Abstract: The sensor electrode has a sensing surface intended to contact a liquid medium for continuous measuring, in combination with a counter electrode and a reference electrode, of the hydrogen peroxide concentration over a concentration range from 0.005 mole/liter to 3 mole/liter, said sensor consisting of a carbon electrode having an open circuit potential between -65 and -85 mV, said open circuit potential being measured with respect to a Ag/AgCl/saturated Cl.sup.- reference electrode in an alkaline solution having a pH between 10.5 and 14, said solution containing hydrogen peroxide at a concentration of more than 0.5 mole/liter.

Abstract: The present invention provides an electrochemical sensor for the detection of hydrogen chloride. In general, the electrochemical sensor comprises a housing having disposed therein a working electrode, a reference electrode and a counter electrode. The electrochemically active surface of the working electrode preferably comprises a gold film having a thickness of approximately 1000 to 3000 .ANG.. Electrical connection is maintained between the working electrode and the counter electrode via an electrolyte present within the housing. The electrochemical gas sensor preferably further comprises circuitry for maintaining the working electrode at a potential in the range of approximately 1025 to approximately 1400 mV versus the normal hydrogen electrode. The present invention also provides a method of using such a sensor to detect hydrogen chloride.

Abstract: An analysis micro-system with integrated cuvette comprising:a chip support (250) having at least one cuvette (252),at least one chip (210) arranged in each cuvette, the chip comprising analysis electrodes (212) and addressing electrodes (214), andconnection means (258, 260, 262) to connect the addressing electrodes to at least one electrical apparatus external to the micro-system.Conforming to the invention, the connection means comprise connection terminals (258) arranged on the support, outside the cuvette (252), and electrical links (260, 262) connecting the connection terminals (258) to the addressing electrodes.Application to the analysis of chemical and biological products.

Abstract: An array of electrodes at the atomic or nano scale (nanoelectrodes) is built on a chip. The spatial distribution, height, width and electrochemical composition of the nanoelectrodes is varied, such that protein-specific electronic receptors are built directly on the chip with the nanoelectrodes without the use of any specific binding agents or molecules. Because of their size, a very large number of different receptors can be built as arrays on a single chip. The chip can be used to detect, characterize and quantify single molecules in solution such as individual proteins, complex protein mixtures, DNA or other molecules.

Abstract: The device (1) has a cell (3) with an electrode structure for carrying out electrochemical detection or measurement of a liquid sample. A means for mechanically or pneumatically drawing the liquid sample into the cavity (20) of the cell (3) is provided. The drawing means may be in the form of a strip (10) which is mechanically drawn through the cell (3) drawing the liquid sample into the cavity (20) of the cell (3). The strip (10) can have a V-shape (44) portion which is placed in the liquid sample before the strip (10) is drawn through the cell (3).

Abstract: An electroanalytical voltammetric cell containing:(a) a cell body housing a counter electrode and a working electrode;(b) means for causing a sample solution to flow through the cell and to fill a space between the counter-electrode and the working electrode; and(c) a vibrator present in the space between the two electrodes which vibrates in order to fully mix the sample solution in the space.

Abstract: A filter has a first filter layer made of TiO.sub.2 of Ti.sub.4 O.sub.7 particles deposited on a second filter layer by stainless steel particles. The first layer has a smaller pore size than the second layer. The construction of the filter, the relative thicknesses of the layers and the resistances thereof to movement therethrough of electrolytically generated gas located between the two layers when the filter is permeated with liquid are such that the gas reaches the upstream side of the filter before the downstream side. In one embodiment stainless steel particles are sintered and rolled with a textured roller before ceramic particles are applied and rolled. An intermediate layer of metal particle peaks and ceramic filled troughs is thus provided which has high tortuosity. The resistance to flow at the metal/ceramic interface can be increased by electrodeposition of metal there.

Abstract: The present invention provides microband electrode array sensors for detecting the presence and measuring the concentration of analytes in a sample. The microband electrodes of the invention have both a width and a thickness of microscopic dimensions. Preferably the width and thickness of the microband electrodes are less than the diffusion length of the analyte(s) of interest. In general, both the thickness and width of the electrodes are less than about 25 micrometers. The electrodes are separated by a gap insulating material that is large enough that the diffusion layers of the electrodes do not overlap such that there is no interference and the currents at the electrodes are additive. Microband electrode arrays of this invention exhibit true steady-state amperometric behavior.

Abstract: There is provided a concentration sensor for measurement of concentrations of one or plural target substances in a system, with a detection electrode of conductive diamond. The measuring method with the concentration sensor involves measuring the reaction potentials of plural target substances in a sample containing and determining the concentrations of the plural substances by use of the difference between the resulting reaction potentials of the respective substances. The measuring method can also determine the concentration of a single substance in a sample containing one kind of target substance.

Abstract: A simple, reliable, and leak-proof three-electrode electrochemical sensor for detection of toxic gases. The sensor comprises a housing having an electrochemical gas sensor cell with an electrolyte and sensing, counter and reference electrodes bonded to conductive plastic. Each of the electrodes is a membrane formed from a fluoropolymer film having a layer adhered thereto of a fluoropolymer-impregnated catalyst. The layers of each of the electrodes are bonded to conductive plastic, and are separated by an absorbent material having an electrolyte absorbed therein. The sensor is particularly intended for detection of carbon monoxide, but may be used to detect other gases.

Abstract: A device for testing body fluids is disclosed, the device comprising an electrode body having an enclosed flow chamber extending longitudinally therethrough. A valve assembly is in liquid communication with the flow chamber and also detachably mounts a syringe thereon. The valve assembly provides liquid communication between a syringe mounted thereon and the flow chamber. A plurality of electrode cells is detachably mounted to the electrode body and is in liquid communication with the flow chamber. The plurality of electrode cells measures electrical resistivity, rH.sub.2, and pH. A circuit electrically connects the plurality of electrodes to an interface providing data output and command input.

Abstract: A sensor for measuring the oxygen and/or unburnt fuel content of a combustion gas includes an outer tube (20) sealed at one end by a pellet (17) of oxygen sensitive solid electrolyte. Solid electrolyte (17) has an electrode (21) formed on the outer side thereon. The sensor also includes an inner tube (13) that is sealed by a disc (14) of solid electrolyte. Disc (14) has electrodes (15, 16) formed on the inner and outer surfaces thereof. The internal side of solid electrolyte (17) is electrically connected to electrode (16). Outer tube (20) is provided with apertures (24) and the annular space between outer tube (20) and inner tube (13) is coated with a platinum catalyst (18). In use, combustion gas contacts outer electrode (21). Combustion gas passes through apertures (24) and along the annular space. During passage of combustion gas through the annular space, the combustion gas comes into close proximity with the oxidation catalyst (18) and the oxidation catalyst (18) acts to equilibrate the combustion gas.

Abstract: The present invention provides an electrochemical sensor for the detection of hydrogen cyanide. In general, the electrochemical sensor includes a housing having disposed therein a working electrode, a reference electrode and a counter electrode. The electrochemically active surfaces of the working electrode and reference electrode preferably comprise silver. Electrical connection is maintained between the working electrode and the counter electrode via an organic electrolyte present within the housing. The electrochemical gas sensor preferably further comprises circuitry for maintaining the working electrode at a potential in the range of approximately +40 mV to approximately -40 mV versus the silver reference electrode. Most preferably, the electrochemical gas sensor comprises circuitry for maintaining the working electrode at a potential of approximately 0 mV versus the silver reference electrode.

Abstract: A conductivity sensor for measuring hematocrit and a sensor housing for a blood analysis instrument using the conductivity sensor are described. The conductivity sensor includes a seven-electrode conductivity measurement cell in which three symmetric pairs of electrodes are arranged on opposite sides of a central electrode. The central electrode is connected to an AC source and the outermost pair of electrodes, which provide a return path for the current, are maintained at a ground or reference potential. The two inner pairs of electrodes measure the voltage drop along the current flow path. This arrangement confines the measurement current and potential within the sensor chamber, thereby preventing the sensor from interfering with other electrochemical sensors that may be provided in the blood analysis instrument. The sensor housing provides a linear arrangement of flow cells defining a fluid flow path through the housing.

Abstract: A gas sensor is provided, having an electrolyte membrane, a sensing electrode, a counter electrode, a diffusion barrier for controlling access of gases to the sensing electrode, and in situ means for removing molecular oxygen from the gases to which the sensing electrode is being exposed.

Abstract: The present invention provides novel microfluidic devices and methods that are useful for performing high-throughput screening assays. In particular, the devices and methods of the invention are useful in screening large numbers of different compounds for their effects on a variety of chemical, and preferably, biochemical systems.

Abstract: An electrochemical oxygen sensor with a measuring electrode, an atmospheric oxygen electrode as a reference electrode, and an auxiliary electrode in an electrolyte is improved such that a stable measured signal is obtained even during changes in the position of the measuring cell. To accomplish this, the auxiliary electrode is arranged in the vicinity of the measuring electrode and a protective electrode is provided between the measuring electrode and the auxiliary electrode.

Abstract: The electroanalytical, voltammetric cell includes a cell body housing, in addition to a reference electrode, a working electrode and, in its lowermost portion, a counter-electrode. An arrangement for deoxygenating the sample solution includes feeding the sample solution through a deoxygenation conduit in contact with a stream of an inert gas. An inlet for the deoxygenated sample solution is provided in the cell body in the space between the working electrode and the counter-electrode, and an exit for the sample solution is provided in the cell body at a level above the working electrode. Vacuum and/or pressure is utilized for causing the sample solution to flow to the exit, to be discharged from the cell above the working electrode, thus assuring that the space between the working electrode and the counter-electrode is constantly filled with sample solution.

Abstract: The present invention is a sensor having an electrode formed in electrical contact with a subminiature through hole. Because of the small diameter of the through hole, the material that fills the through hole and the through hole itself have an essentially negligible effect on the sensor. A relatively large number of sensors can be formed on the surface of the substrate within a relatively small fluid flowcell. Thus, more information can be attained using less analyte. The sensors of the present invention are preferably disposed on an alumina substrate which is essentially impervious to aqueous electrolytes and blood over long periods of storage in potentially corrosive environments.