Abstract: A reagent composition for a biosensor sensor strip is disclosed that provides for rapid rehydration after drying. The composition includes porous particles and is preferably formed as a colloidal suspension. The dried reagent composition including porous particles may provide analytically useful output from the sensor strip in a shorter time period than observed from dried reagent compositions using solid particles. The output signal from the porous particle compositions may be correlated to the analyte concentration of a sample within about two seconds. In this manner, an accurate concentration determination of an analyte concentration in a sample may be obtained in less time than from sensor strips including conventional compositions. The reagent composition including the porous particles also may allow for the redox reaction between the reagents and the analyte to reach a maximum kinetic performance in a shorter time period than observed from conventional sensor strips.

Abstract: Catalysts that include at least one catalytically active element and one helper catalyst can be used to increase the rate or lower the overpotential of chemical reactions. The helper catalyst can simultaneously act as a director molecule, suppressing undesired reactions and thus increasing selectivity toward the desired reaction. These catalysts can be useful for a variety of chemical reactions including, in particular, the electrochemical conversion of CO2 or formic acid. The catalysts can also suppress H2 evolution, permitting electrochemical cell operation at potentials below RHE. Chemical processes and devices using the catalysts are also disclosed, including processes to produce CO, OH?, HCO?, H2CO, (HCO2)?, H2CO2, CH3OH, CH4, C2H4, CH3CH2OH, CH3COO?, CH3COOH, C2H6, O2, H2, (COOH)2, or (COO?)2, and a specific device, namely, a CO2 sensor.

Abstract: The present invention provides a biosensor including a working electrode or working electrodes on which a reaction material or a bonding material is immobilized, where the reaction material is reactive with a target material so as to produce a product, and the bonding material is bondable with a target material; a counter electrode; and a reaction section for holding a sample liquid containing the target material, the working electrode and the counter electrode being provided on a bottom surface of the reaction section, and the working electrode occupying the bottom surface of the reaction section by a ratio of 0.7 or greater.

Abstract: Methods and systems for measuring the oxidation-reduction potential of a fluid sample are provided. The system includes a test strip with a sample chamber adapted to receive a fluid sample. The sample chamber can be associated with a filter membrane. The test strip also includes a reference cell. The oxidation-reduction potential of a fluid sample placed in the sample chamber can be read by a readout device interconnected to a test lead that is in electrical contact with the sample chamber, and a reference lead that is in electrical contact with the reference cell. Electrical contact between a fluid sample placed in the sample chamber and the reference cell can be established by a bridge. The oxidation-reduction potential may be read as an electrical potential between the test lead and the reference lead of the test strip.

Abstract: Disclosed in certain embodiments is a method of determining the individual concentration of different antioxidants of the same class in a sample comprising contacting the sample with an effective amount of phenol; and analyzing the sample by voltammetry.

Abstract: The present invention relates to devices, systems, and methods for determination of ionizing radiation. In some embodiments, the devices comprise nanocomposite materials containing nanostructures (e.g., carbon nanotubes) dispersed in radiation sensitive polymers. In some cases, the device may include a conductive pathway that may be affected upon exposure to ionizing radiation. Embodiments described herein may provide inexpensive, large area, low power, and highly sensitive radiation detection materials/devices.

Abstract: Methods and systems for screening for the effect of bath composition on the performance of electroplating, electroless-plating, electrochemical-etching, electropolishing, and chemical-etching processes are provided. The methods and systems use microfluidic channels that allow for etching or plating studies on an electrode exposed to a multitude of bath compositions at different positions on its surface. After deposition or etching, the electrode surface can be quickly and easily detached from the device for analysis of deposited or etched film properties.

Abstract: Provided herein is technology relating to testing biological samples and particularly, but not exclusively, to devices, systems, and kits for performing multiple, simultaneous real-time assays on a sample in a single-use disposable format. For example, the technology relates to an apparatus that finds use, for example, for point-of-care diagnostics, including use at accident sites, emergency rooms, in surgery, in intensive care units, as well as for non-medical applications.

Abstract: Provided is an electrochemical sensor device capable of micromachining a channel while maintaining its measurement sensitivity and of reliably quantitating an analyte in a trace amount of a sample. An electrochemical sensor device includes: a channel portion formed in a substrate; and working electrodes for subjecting an analyte in a solution flowing in the channel portion to electrochemical measurement, the electrochemical sensor device includes a plurality of measuring portions individually provided with the working electrodes, and each of the working electrodes has a plurality of conductive protrusion portions formed to protrude from a bottom surface of each of the measuring portions.

Abstract: When a detection signal obtained from the cell of a gas sensor (S15) has reached a start determination value (specifically, when the output voltage of the cell is higher than 600 mV (S16: YES) or lower than 300 mV (S17: YES)), a pulse voltage is applied to the cell (S18), and a start-time internal resistance is obtained on the basis of the detection signal having changed as a result of application of the pulse voltage (S20). The start-time internal resistance is compared with a deterioration determination value set in advance (S21). A target resistance of the cell used in temperature control (energization control) for the heater is corrected in accordance with the result of the comparison (S28). Thus, the temperature of the cell can be stably maintained constant irrespective of deterioration of the cell.

Abstract: An analysis device is disclosed which includes an electron detection medium to obtain information needed for analyzing an analyte in correlation with an electron transfer level, and a reagent part which is disposed on the electron detection medium and includes an electron transporting substance to transport electrons between the analyte and the electron detection medium, the electron transporting substance including a water-soluble aromatic heterocycle compound, and being free of a metal complex. An analysis method using the analysis device is also disclosed.

Abstract: Disclosed is a method and apparatus for detecting the concentration of a lipophilic analyte of interest in a complex sample matrix. The method comprises extracting the analyte of interest from said sample into an organic solvent comprising a dissolved electrolyte; providing a free radical species, preferably a free oxygen radical species, in said organic solvent; reacting the Canalyte of interest with said free radical species; and performing a measurement to detect the concentration of the free radical-reacted analyte reaction product.

Abstract: In order to provide a method for electrochemically detecting an analyte which can detect an analyte with high detection sensitivity, when detecting an analyte S trapped on a working electrode, a label binding substance 90 in which a labeling substance 93 and a first binding substance 92 which traps the analyte S are at least retained on a support 91 composed of polypeptide is brought into contact with the analyte. Alternatively, a complex containing the analyte S and a label binding substance 290 in which a labeling substance 293 is retained on a binding substance 291 which binds to the analyte S via a modulator 292 is formed. Then, the labeling substance present on the working electrode is electrochemically detected.

Abstract: The present invention provides novel osmium-based electrochemical species for the detection of wide variety of analytes using immunological techniques. The present invention also provides diagnostic kits and test sensors supporting electrode structures that can be used with the osmium-based electrochemical species. The test sensor can be fabricated to support interdigitated arrays of electrodes that have been designed to provide amplification of the electrical signal amplification desired to analyze analytes that may be present at low concentrations.

Abstract: The present invention provides novel osmium-based electrochemical species for the detection of wide variety of analytes using immunological techniques. The present invention also provides diagnostic kits and test sensors supporting electrode structures that can be used with the osmium-based electrochemical species. The test sensor can be fabricated to support interdigitated arrays of electrodes that have been designed to provide amplification of the electrical signal amplification desired to analyze analytes that may be present at low concentrations.

Abstract: An electrochemical sensing method that includes (a) providing an electrochemical cell having a working electrode and a pseudo reference electrode; (b) providing a sample comprising a metal, the sample being in contact with the working electrode and the metal being capable of being oxidized or reduced at the working electrode when the metal is bound to the working electrode; (c) preconditioning the working electrode by (i) applying a time varying preconditioning potential between the working and pseudo reference electrodes; and/or (ii) baking the working electrode; and/or (iii) air-ageing the working electrode; and (d) applying a measuring potential between the working and pseudo reference electrodes and, during application of said measuring potential, measuring the current generated by oxidation/reduction of the metal at the working electrode.

Abstract: Disclosed herein is an electrochemical biosensor measuring device which comprises at least two photodiodes for emitting light beams at regular time intervals in a sequential manner, with the insertion of an electrochemical biosensor thereto, and a detector for sensing the emitted light beams, thereby identifying the production lot information recorded on a production lot information identification portion on the electrochemical biosensor. Thus, the device enjoys economic advantages of not requiring a high-priced optical filter in detecting the light absorbed through or reflected from the production identification information recorded in biosensor and a complicated software algorithm to recover the production lot information.

Abstract: Improvements in references electrodes, halogen sensors, pH sensors, TDS sensors, combinations thereof, and related methods.

Abstract: A sensor control apparatus is disclosed, including a preliminary control for supplying a constant current to a second oxygen pump cell of a gas sensor for a constant period of time so as to control to a constant level the amount of oxygen pumped out from a second measurement chamber (S40 to S50). At the beginning of drive control (S55 to S80), oxygen is pumped back into the second measurement chamber. During the pumping back operation, an NOX concentration correspondence value has a large time course change and is not stable. The NOX concentration correspondence value is corrected using correction data common among gas sensors, wherein the timing for applying the correction data is adjusted by making use of an application time determined in accordance with individual differences of each gas sensor.

Abstract: A precious metal testing apparatus and methods adapted to analyze impurities in a precious metal test sample is described. The testing apparatus contains a test probe that has a replaceable portion and that is connected to a meter to measure resistance. The replaceable portion contains or forms a reservoir that includes at least one electrolyte component, a conductive member, and a fibrous tip. The electrolyte component is fluidly associated with a fiber tip and the conductive member contacts an electrical contact located outside the reservoir. Methods of testing and instructions regarding such methods are also included.

Abstract: A system and method for voltammetric analysis of a liquid sample solution.

Abstract: A wellbore tool has an electrochemical sensor for measuring the amount of hydrogen sulphide or thiols in a fluid downhole in a wellbore. The sensor comprises a temperature- and pressure-resistant housing containing a flow path for the fluids. The fluids flow over one side of a gas permeable membrane the other side of the membrane being exposed to a chamber containing at least two electrodes and containing a reaction solution which together with the hydrogen sulphide or thiols create a redox reaction resulting in an electrical current dependent upon the amount of hydrogen sulphide or thiols in the fluid. Measurement is made by passing formation fluid along the flow path and repeatedly applying varying potential to one electrode and measuring the peak current flowing between that electrode and a second electrode.

Abstract: Methods are described for reading a chemically-sensitive field-effect transistor (chemFET) with an improved signal-to-noise ratio. In one embodiment, a method is described for reading a chemFET having a first terminal and a second terminal, and a floating gate coupled to a passivation layer. The method includes biasing the first terminal of the chemFET to a first bias voltage during a read interval. The second terminal of the chemFET is coupled to a data line during the read interval. A current is induced through the chemFET via the data line. An output signal proportional to an integral of a voltage or current on the data line is generated in response to the induced current through the chemFET during the read interval.

Abstract: Nanostructures comprising carbon and metal catalyst that are formed on a substrate, such as a silicon substrate, are contacted with a composition that, among other useful modifications, protects the nano structures and renders them stable in the presence of oxidizing agents in an aqueous environment. The protected nano structures are rendered stable over an extended period of time and thereby remain useful during such period as components of an electrode, for example, for detecting electrochemical species such as free chlorine, total chlorine, or both in water.

Abstract: A gas sensor element has a first cell, a second cell, and a solid electrolyte layer having proton conductivity commonly used by the first cell and the second cell. The first cell has a first cathode and a first anode exposed to the target detection gas containing hydrogen atoms. The second cell has a second anode, a second cathode, and a shield layer with which the second anode is covered. A voltage is supplied to the first and second cells. A gas concentration of the target detection gas is calculated on the basis of a difference between a current of the first cell and a current of the second cell because the current in the first cell is a sum of proton conductivity current and an electron conductivity current. The current in the second cell is an electron conductive current only.

Abstract: A method and an apparatus for determining the total peroxide content of a cellulose pulp suspension in the pulp suspension bleaching stage, wherein the bleaching chemical is peroxide. A sample is taken from the pulp suspension, which sample is measured in a measuring device (25, 25?). Before measuring, the pH of the sample is adjusted and after that the total peroxide content or the perhydroxyl content of the sample is measured, of which measurement the total peroxide content of the sample is determined.

Abstract: A sensor system including devices and methods for determining the concentration of an analyte in a sample is described. Input signals including amperometric and voltammetric duty cycles of excitations and relaxations may provide a shorter analysis time and/or improve the accuracy and/or precision of the analysis. The disclosed system may reduce analysis errors, thus improving measurement performance, by adjusting the potential and/or scan rate in response to output currents obtained from voltammetric scans. The disclosed system also may determine the concentration of more than one ionizable species in the sample by adjusting the potential and/or scan rate in response to output currents obtained from voltammetric scans. The multiple, determined concentrations may be used to determine the concentration of multiple analytes or to correct the concentration determined for an analyte, thus improving the measurement performance of the system.

Abstract: Methods and apparatuses are provided wherein a sensor which comprises at least two electrodes and a movable part is alternately biased with at least two different voltages.

Abstract: Methods and systems for measuring the oxidation-reduction potential of a fluid sample are provided. The system includes a test strip with a sample chamber adapted to receive a fluid sample. The sample chamber can be associated with a filter membrane. The test strip also includes a reference cell. The oxidation-reduction potential of a fluid sample placed in the sample chamber can be read by a readout device interconnected to a test lead that is in electrical contact with the sample chamber, and a reference lead that is in electrical contact with the reference cell. Electrical contact between a fluid sample placed in the sample chamber and the reference cell can be established by a bridge. The oxidation-reduction potential may be read as an electrical potential between the test lead and the reference lead of the test strip.

Abstract: A porous structure including a pair of electrodes disposed in a flow direction of exhaust gas and a solid electrolyte interposed between the electrodes is arranged in an exhaust passage of an internal combustion engine, and the amount of a particulate matter in exhaust gas is specified based on a potential difference generated between the electrodes.

Abstract: The presence of a select analyte such as glucose in the sample is evaluated in an electrochemical system using a conduction cell-type apparatus. A potential or current is generated between the two electrodes of the cell sufficient to bring about oxidation or reduction of the analyte or of a mediator in an analyte-detection redox system, thereby forming a chemical potential gradient of the analyte or mediator between the two electrodes after the gradient is established, the applied potential or current is discontinued and an analyte-independent signal is obtained from the relaxation of the chemical potential gradient. The analyte-independent signal is used to correct the analyte-dependent signal obtained during application of the potential or current.

Abstract: A small, portable, and inexpensive potentiostat circuit that is suitable for wide-spread electrochemical analysis is disclosed. The potentiostat may be fabricated as a stand-alone electrical component or it may be fabricated in conjunction with a Programmable System-on-Chip (SoC) to facilitate on-the-fly calibration and configuration.

Abstract: There is provided a sensor testing method including: applying at least one of a first voltage that obtains a response caused by a substance and a second voltage that either obtains no response or substantially no response caused by the substance across a first electrode and a second electrode of a sensor; measuring current flowing between the first electrode and the second electrode; and determining whether or not there is a defect present in the sensor based on a quantity related to an amount of change per specific period of time of a current measured when the first voltage and/or the second voltage have been applied.

Abstract: A meter and sensors, for use in combination, where no calibration code has to be entered by the user or is read by the meter. The meter is configured with a predetermined slope and y-intercept built into the meter. If the slope and y-intercept of the sensor are within a predetermined area or grid, or otherwise close to the slope and y-intercept of the meter, the batch of sensors is acceptable for use with that meter for providing accurate analyte concentration results.

Abstract: The present invention provides a novel biosensing and measuring method. The biosensor of the present invention comprises an electrode having a nanopore structured and bio-communicationally active cyclodextrin attached thereto. The biosensor of the present invention has demonstrated robust analytical performance for direct glucose measurement without mediators, nor using native enzyme, nor using antibodies, which is especially beneficial in care diagnostic applications.

Abstract: Microelectrodes, microelectrode formation, and methods of utilizing microelectrodes for characterizing properties of localized environments and substrates are provided. A microelectrode can include a tungsten wire comprising a shaft and a conical tip. The conical tip can include an electroactive area. Further, the microelectrode can include an electroactive coating layer covering one or more surface of the tungsten wire. The tungsten wire surfaces can include a surface of the conical tip. An insulating layer can at least partially cover the shaft.

Abstract: Disclosed herein are fluid distribution methods and assemblies for supplying fluid to test assemblies. One embodiment of a fluid distribution assembly comprises at least two input lines each configured to supply a fluid. A source selection component is connected to the input lines and configured to receive the fluid of the input lines and select from the fluids a target fluid. A range selection component is configured to receive the target fluid and to select a flow range of the target fluid, outputting the target fluid to a flow component comprising a first flow adjustment component having a first flow rate resolution and a second flow adjustment component having a second flow rate resolution. The range selection component is configured to selectively output the target fluid to one of the first flow adjustment component and the second flow adjustment component based on the selected flow range.

Abstract: The invention provides an electrochemical sensor comprising an electrode assembly which comprises at least two electrodes, one of the electrodes comprising a metal species capable of catalysing the oxidation of hydrogen and/or methane. The sensor may be used in the detection and quantification of hydrogen and/or methane in exhaled breath, for example as a means of diagnosing lactose malabsorption or lactose intolerance.

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: A configuration is disclosed. In one aspect, the configuration includes a substantially planar electrode layer, in a first plane. The configuration further includes a substantially planar two-dimensional electron gas (2DEG) layer electrically connected in series with the electrode layer. The 2DEG layer is provided in a second plane substantially parallel with the first plane and located at a predetermined distance, in a direction orthogonal to the first plane, from the first plane. The 2DEG layer and the electrode layer are patterned such that the electrode layer overlays a part of the 2DEG layer, wherein the predetermined distance between the first plane and the second plane is selected to be sufficiently small for allowing electrostatic interaction between the electrode layer and the 2DEG layer.

Abstract: Microfluidic, electrochemical devices are described. The microfluidic, electrochemical device comprises one or more electrode(s) on a substrate and a patterned porous, hydrophilic layer having a fluid-impermeable barrier which substantially permeates the thickness of the porous, hydrophilic layer and defines boundaries of one or more hydrophilic channels within the patterned porous, hydrophilic layer, wherein the hydrophilic channel(s) comprises a hydrophilic region which is in fluidic communication with the electrode(s). In some embodiments, the electrodes comprise a working electrode, a counter electrode, and a reference electrode. In some embodiments, the microfluidic, electrochemical device further comprises a fluid sink. The method of assembling the microfluidic, electrochemical device is described. The method of using the device for electrochemical analysis of one or more analytes is also described.

Abstract: The invention relates to an electrochemical half cell for application in an electrochemical sensor, wherein a fill electrolyte (10) of the half cell is in contact with an external medium via a liquid junction (5), characterized in that the liquid junction (5) is controllable as regards its permeability and/or its flow.

Abstract: A sensor apparatus for an electrochemical measuring device. The apparatus has at least one electrode, which can be heated using a heating current in the form of an alternating current, and a first and a second connection for the supply line for the heating current. The electrochemical measuring device is connected to the electrode by a third connection. In this case, the apparatus has the third connection connected to the electrode by a bridge circuit, which is also connected to the first and second connections. There also is provided a method for carrying out electrochemical measurements at elevated temperature. The sensor apparatus and the method for carrying out electrochemical measurements enable electrochemical measurements with little interference and directly heated electrodes in conjunction with a simplified design of the electrodes.

Abstract: A method for characterizing refinery feedstocks according to their corrosivity is provided. The characterization is based on any of: dissociation of acids in the crude, breakup of naphthenic acid molecular associations, and/or dissociation of sulfur compounds in the feedstocks. In one embodiment, the characterization is done via vibrational spectroscopic measurements over a range of temperature, e.g., from ambient to 700° F. The method can be practiced in any of refinery, terminal, and laboratories. It can be used in conjunction with models and hardware to optimize the usage of refinery feedstocks in the blending and valuation of the feedstocks.

Abstract: Refinery feedstocks can be characterized based on any of: dissociation of acids in the crude, breakup of naphthenic acid molecular associations, and/or dissociation of sulfur compounds in the feedstocks. The characterization is performed as a function of temperature via any of electrical resistivity measurement, vibrational spectroscopic analysis, voltammetry, electrochemical impedance spectroscopy (EIS) and combinations thereof The method can be practiced in any of refinery, terminal, and laboratories. It can be used in conjunction with models and hardware to optimize the usage of refinery feedstocks in the blending and valuation of the feedstocks. In one embodiment, the characterization of refinery feedstocks is via the use of EIS.

Abstract: There is described a method for determining single cell current efficiency in an electrolyser, the method comprising: measuring voltage of a plurality of single cells in the electrolyser; measuring electrolyser current feeding the single cells; detecting one of a shutdown period and a start-up period; and for each single cell: determining a time t taken for a voltage level to reach a predetermined occurrence in a voltage curve after a polarization current has been triggered; and calculating cell current efficiency as a function of the time t.

Abstract: The present invention is directed to electrochemical sensors and systems and methods for electrochemically sensing a particular constituent within a fluid through the use of a diagnostic test. The methods provide for automatic discrimination of sample from control or standard solutions. A device and system used to determine a constituent level within a fluid that employ such automatic sample discrimination methods or specially formulated solutions is also provided.

Abstract: A sample substance S is captured by a capture substance 10 which is immobilized on a working electrode body 161 to provide a method of electrochemically detecting a sample substance capable of detecting the sample substance with high sensitivity. A complex which includes, on a soluble carrier 21, a sample substance S and a labeled binder 20 that has a modified labeled substance 23 containing a labeled substance 20 bound to modified labeled substance 23 containing a labeled substance 24 and a binder 22 that binds to the sample substance S, formed on the working electrode 161. The soluble carrier 21 is dissolved, and the modified labeled substance 23 is attracted to the working electrode 161.

Abstract: A degradation detector of an exhaust gas sensor is disclosed. The detector comprises a first heater resistance estimator (16) for estimating a resistance of a heater that heats the exhaust gas sensor, based on a device resistance of the exhaust gas sensor; a heater resistance calculator (17) for calculating a resistance of the heater, based on a heater current of the heater; and a degradation determiner (18) for determining whether the exhaust gas sensor is degraded, by comparing the estimated resistance of the heater and the calculated resistance of the heater.

Abstract: Disclosed in certain embodiments is a method of determining the individual concentration of different antioxidants of the same class in a sample comprising contacting the sample with an effective amount of phenol; and analyzing the sample by voltammetry.