Abstract: A method for determining a concentration of an analyte is disclosed. The method includes applying a potential excitation to a fluid sample containing an analyte and determining if a current decay curve associated with the fluid sample has entered an analyte depletion stage. The method also includes measuring a plurality of current values associated with the fluid sample during the analyte depletion stage and calculating an analyte concentration based on at least one of the plurality of current values.

Abstract: This invention is a method for determining a concentration of an analyte. The steps include applying a potential excitation to a fluid sample containing an analyte, and measuring a current associated with the potential excitation at a plurality of time-points. The method also includes calculating an analyte concentration based on the measured current and a calibration curve, wherein the calibration curve is selected from a plurality of calibration curves and each calibration curve is associated with a time-segment selected from a plurality of time-segments.

Abstract: Disclosed herein is a sensor comprising a conduit; the conduit comprising an organic polymer; a working electrode; the working electrode being etched and decorated with a nanostructured material; a reference electrode; and a counter electrode; the working electrode, the reference electrode and the counter electrode being disposed in the conduit; the working electrode, the reference electrode and the counter electrode being separated from each other by an electrically insulating material; and wherein a cross-sectional area of the conduit that comprises a section of the working electrode, a section of the reference electrode and a section of the counter electrode is exposed to detect analytes.

Abstract: The present invention provides methods and apparatuses for analyte detection.

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 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 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: Novel transition metal complexes of iron, cobalt, ruthenium, osmium, and vanadium are described. The transition metal complexes can be used as redox mediators in enzyme-based electrochemical sensors. The transition metal complexes include substituted or unsubstituted (pyridyl)imidazole ligands. Transition metal complexes attached to polymeric backbones are also described.

Abstract: The present invention relates to an apparatus for conducting a variety of assays for the determination of analytes in liquid samples, and relates to the methods for such assays. In particular, the invention relates to a single-use cartridge designed to be adaptable to a variety of real-time assay protocols, preferably assays for the determination of analytes in biological samples using immunosensors or other ligand/ligand receptor-based biosensor embodiments. The cartridge provides novel features for processing a metered portion of a sample, for precise and flexible control of the movement of a sample or second fluid within the cartridge, for the amending of solutions with additional compounds during an assay, and for the construction of immunosensors capable of adaptation to diverse analyte measurements.

Abstract: Biological reagent compositions with improved sensitivity to the concentration of blood glucose in patient samples for use in measuring systems and methods. The reagent compositions comprise a glucose oxidoreductase enzyme, a flavin nucleoside coenzyme and a mediator formulation. The mediator formulation comprises at least one electroactive organic molecule and at least one coordination complex.

Abstract: A biosensor containing ruthenium, measurement using the same, and the application thereof. The biosensor comprises an extended gate field effect transistor (EGFET) structure, including a metal oxide semiconductor field effect transistor (MOSFET), a sensing unit comprising a substrate, a layer comprising ruthenium on the substrate, and a metal wire connecting the MOSFET and the sensing unit.

Abstract: A biosensor can supply a sample solution accurately and easily, and includes a capillary for collecting a sample solution and analyzes a specific substance in the sample solution, an air hole, and at least two supply ports, i.e., a sample supply port and an auxiliary sample supply port, so that supply of the sample solution can be performed from either of the supply ports. Even when the sample supply port is closed up with a fingertip or the like and supply of the sample solution is stopped, the sample solution can be quickly supplied from the other auxiliary sample supply port.

Abstract: A molecular electronic device, and a method of fabricating the same, includes a first electrode having a plurality of prominences and depressions on which a plurality of molecules are self-assembled. Capacitance of a molecular electronic device used as a capacitor is increased by forming prominences and depressions on the surface of the first electrode thereby enabling more molecules to be self-assembled on the surface of the lower electrode.

Abstract: A biosensor is disclosed comprising a support; a conductive layer composed of an electrical conductive material such as noble metal, for example gold or palladium, and carbon; slits parallel to and perpendicular to the side of the support; working, counter, and detecting electrodes; a spacer which covers the working, counter, and detecting electrodes on the support; a rectangular cutout in the spacer forming a specimen supply path; an inlet to the specimen supply path; a reagent layer formed by applying a reagent containing an enzyme to the working, counter, and detecting electrodes, which are exposed through the cutout in the spacer; and a cover over the spacer. The biosensor can be formed by a simple method, and provides a uniform reagent layer on the electrodes regardless of the reagent composition.

Abstract: The present invention is based on the discovery of NAD+ and NADP+ mediator compounds that do not bind irreversibly to thiol groups in the active sites of intracellular dehydrogenase enzymes. Such mediator compounds avoid a common mode of enzyme inhibition. The mediators can therefore increase the stability and reliability of the electrical response in amperometric electrodes constructed from NAD- or NADP-dependent enzymes.

Abstract: The present invention relates to a biosensor including: a bottom plate having a base film having a lead mounted at one side of the top surface thereof, an electrode member formed on the base film, a spacer formed on the top surface of the electrode member so as to secure a recess having a predetermined width formed on the electrode member, and an enzyme reaction layer formed transversely on the top surface of the electrode member in such a fashion as to be positioned in the recess of the spacer; and a top plate formed integrally with the bottom plate and having the same configuration as the bottom plate.

Abstract: An electrochemical-based analytical test strip includes an electrically-insulating substrate, a patterned conductive layer disposed over the electrically-insulating substrate, a patterned insulating layer disposed over the patterned conductive layer, an enzymatic reagent layer disposed over the patterned conductive layer, a patterned adhesive layer disposed above the enzymatic reagent layer and a top layer disposed over the enzymatic reagent layer. In addition, the test strip has a sample-receiving chamber defined by the electrically-insulating substrate, the patterned conductive layer, the patterned insulating layer, the enzymatic reagent layer, the patterned adhesive layer and the top layer. The sample receiving chamber of the test strip has a working portion and a non-working portion and the top layer has a first portion and an opaque second portion.

Abstract: An electrochemical sensor strip has a base and a first electrode and a second electrode on the base. An oxidoreductase enzyme and a mediator are on the first electrode, and a soluble redox species is on the second electrode. The soluble redox species may be an organotransition metal complex, a transition metal coordination complex, an electroactive organic molecule, or mixtures thereof.

Abstract: A biosensor can supply a sample solution accurately and easily, and includes a capillary for collecting a sample solution and analyzes a specific substance in the sample solution, an air hole, and at least two supply ports, i.e., a sample supply port and an auxiliary sample supply port, so that supply of the sample solution can be performed from either of the supply ports. Even when the sample supply port is closed up with a fingertip or the like and supply of the sample solution is stopped, the sample solution can be quickly supplied from the other auxiliary sample supply port.

Abstract: The present invention is based on the discovery of NAD+ and NADP+ mediator compounds that do not bind irreversibly to thiol groups in the active sites of intracellular dehydrogenase enzymes. Such mediator compounds avoid a common mode of enzyme inhibition. The mediators can therefore increase the stability and reliability of the electrical response in amperometric electrodes constructed from NAD- or NADP-dependent enzymes.

Abstract: A biosensor is disclosed comprising a support; a conductive layer composed of an electrical conductive material such as a noble metal, for example gold or palladium, and carbon; slits parallel to and perpendicular to the side of the support; working, counter, and detecting electrodes; a spacer which covers the working, counter, and detecting electrodes on the support; a rectangular cutout in the spacer forming a specimen supply path; an inlet to the specimen supply path; a reagent layer formed by applying a reagent containing an enzyme to the working, counter, and detecting electrodes, which are exposed through the cutout in the spacer; and a cover over the spacer. The biosensor can be formed by a simple method, and provides a uniform reagent layer on the electrodes regardless of the reagent composition.

Abstract: An integrated lancing and measurement device is provided comprising a sensor designed to determine the amount and/or concentration of analyte in a biological fluid having a volume of less than about 1 ?l. A piercing member is adapted to pierce and retract from a site on the patient to cause the fluid to flow therefrom, and the sensor is positioned adjacent to the site on the patient so as to receive the fluid flowing from the site to generate an electrical signal indicative of the concentration of the analyte in the fluid. The sensor is comprised of a working electrode comprising an analyte-responsive enzyme and a redox mediator, and a counter electrode. An analyte monitor is operatively connected to the sensor and adapted to measure the signal generated by the sensor. Also provided are analyte measuring methods that optionally employ the integrated lancing and measurement device.

Abstract: A method of determining concentrations of a plurality of analytes from a single blood sample placed in a single opening. A portion of the single blood sample is absorbed by a test matrix that includes a plurality of layers and a chromogenic agent. A colored response is generated by the test matrix. The colored response is proportional to the concentration of a first analyte. A portion of the single blood sample is drawn into a capillary tube and placed in contact with an electrode and a counter-electrode. An electrical property of the single blood sample is analyzed through the electrode and counter-electrode. The electrical property is proportional to the concentration of a second analyte in the single blood sample.

Abstract: A system for more accurately measuring glucose in a sample includes a first glucose-sensing electrode incorporating a quantity of glucose oxidase, a second glucose-sensing electrode incorporating a quantity of PQQ-glucose dehydrogenase, a reference electrode, and means for selecting between a first glucose measurement made with the first glucose-sensing electrode and a second glucose measurement made with the second glucose-sensing electrode.

Abstract: The present invention provides a sensor, such as a biosensor, comprising at least one self-assembled monolayer (SAM) comprising analyte-sensitive groups, such as glucose-sensitive groups, attached to the surface of the outer wall of a carbon nanotube (CNT), such as a single-walled carbon nanotube (SWNT), by terminal groups, which bind to a thin layer of a metal or metal oxide, which has been deposited on the surface of the outer wall of the nanotube.

Abstract: Bis-(4,4?dimethyl-2,2?bipyridyl) picolinate osmium complexes are useful as mediators in the electrochemical test strips, such as those used in the detection of glucose.

Abstract: Disclosed are a tyrosinase enzyme electrode containing metal nanoparticles and its producing method. Metal nanoparticles are applied to a surface of a support with high chemical stability. Also, a buffer layer consisting of a self-assembled monolayer is formed on the metal nanoparticles. Such self-assembled monolayer is used to immobilize tyrosinase enzyme which was subsequently prepared. In other words, the self-assembled monolayer is arranged between the metal nanoparticles and the tyrosinase enzyme so as to immobilize the tyrosinase enzyme on the support. Introduction of the metal nanoparticles into the electrode contributes to improvement in detection limits of the tyrosinase enzyme electrode. In addition, the introduction of substrate induces the activation of enzyme.

Abstract: A biosensor strip having a low profile for reducing the volume of liquid sample needed to perform an assay. In one embodiment, the biosensor strip includes an electrode support; an electrode arrangement on the electrode support; a cover; a sample chamber; and an incompressible element placed between the cover and the electrode support, the incompressible element providing an opening in at least one side or in the distal end of the sample chamber to provide at least one vent in the sample chamber. In another embodiment, the biosensor strip has an electrode support; an electrode arrangement on the electrode support; a cover; and a sample chamber, the cover having a plurality of openings formed therein, at least one of the openings in register with the sample chamber. The invention further includes methods for preparing such a biosensor strips in a continuous manner.

Abstract: A biosensor comprises a space part for sucking and housing a sample formed of two upper and lower plates, the two plates being stuck together by an adhesive layer, the space part for sucking and housing the sample being constituted so as to be partially opened in the peripheral part and partially closed by the adhesive layer, and has a working electrode having at least glucose oxidase immobilized thereon and a counter electrode on the same plane of the plate.

Abstract: Novel transition metal complexes of iron, cobalt, ruthenium, osmium, and vanadium are described. The transition metal complexes can be used as redox mediators in enzyme based electrochemical sensors. In such instances, transition metal complexes accept electrons from, or transfer electrons to, enzymes at a high rate and also exchange electrons rapidly with the sensor. The transition metal complexes include at least one substituted or unsubstituted biimidazole ligand and may further include a second substituted or unsubstituted biimidazole ligand or a substituted or unsubstituted bipyridine or pyridylimidazole ligand. Transition metal complexes attached to polymeric backbones are also described.

Abstract: A sensor designed to determine the amount and concentration of analyte in a sample having a volume of less than about 1 ?L. The sensor has a working electrode coated with a non-leachable redox mediator. The redox mediator acts as an electron transfer agent between the analyte and the electrode. In addition, a second electron transfer agent, such as an enzyme, can be added to facilitate the electrooxidation or electroreduction of the analyte. The redox mediator is typically a redox compound bound to a polymer. The preferred redox mediators are air-oxidizable. The amount of analyte can be determined by coulometry, amperometry, voltammetry, and potentiometry. 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. An enzyme capable of catalyzing the electrooxidation or electroreduction of the biomolecule is provided as a second electron transfer agent.

Abstract: A biosensor strip having a low profile for reducing the volume of liquid sample needed to perform an assay. In one embodiment, the biosensor strip comprises an electrode support; an electrode arrangement on said electrode support; a cover; a sample flow channel; and an incompressible element placed between said cover and said electrode support, the incompressible element providing an opening in at least one side or in the distal end of said sample flow channel to provide at least one vent in said sample flow channel. In another embodiment, the biosensor strip comprises an electrode support; an electrode arrangement on said electrode support; a cover; and a sample flow channel, the cover having a plurality of openings formed therein, at least one of the openings in register with said sample flow channel. The invention further includes methods for preparing such a biosensor strips in a continuous manner.

Abstract: A biochemical test strip, a measurement device, and a biochemical test system are provided. The biochemical test strip has a first connection region, a second connection region and a sensing region defined thereon, and includes an insulating substrate, a set of electrodes, an insulating slice and an identifying unit. The set of the electrodes is disposed on the insulating substrate, and one end of the set of electrodes is in the first connection region. The insulating slice is disposed on the set of the electrodes and exposes at least the first connection region. The identifying unit including a plurality of electronic elements is formed on a surface of the insulating slice in the second connection region, wherein the second connection region is different from the first connection region. The type of the biochemical test strip is determined by the number and location of the plurality of electronic elements.

Abstract: Disclosed embodiments concern site-specific, enzymatic-directed deposition of elemental metal for in-situ analysis. Enzyme substrates are contacted with metal ions and subsequently direct the deposition of elemental metals. Sensitive and selective detection of target molecules, such as biomarkers in various biological samples, can be obtained using various methods, such as in-situ chromogenic immunohistochemical (IHC) detection with bright field light microscopy.

Abstract: A method for determining an analyte concentration in blood is described that reduces the effects of hematocrit using a test strip attached to a test meter. The test strip includes a working electrode and a reference electrode. The test meter applies a test voltage between the working electrode and the reference electrode. After a user applies a blood sample containing an analyte onto the test strip, the test meter measures a plurality of test currents for a test time interval.

Abstract: According to one embodiment of the present invention, an electrochemical sensor (10) for detecting the concentration of analyte in a fluid test sample is disclosed. The sensor (10) includes a counter electrode having a high-resistance portion for use in detecting whether a predetermined amount of sample has been received by the test sensor.

Abstract: The present invention relates to a carbon nanotube transistor biosensor with aptamers and a method for detecting a target material using the same, more particularly to a carbon nanotube transistor biosensor recognizing the target material, i.e., a specific molecule (such as a protein, a peptide, an amino acid, and an organic/inorganic compound) by using DNA aptamers and a method for screening a target material using the same. In the biosensor of the present invention, the aptamers binding specifically to a particular protein are adsorbed on a carbon nanotube constituting the channel domain of carbon nanotube transistor to easily detect/identify a particular protein via the electric conductivity of carbon nanotube that varies if the particular protein is exposed to corresponding aptamers.

Abstract: Electrodes and configurations for electrochemical bioreactor systems that can use electrical energy as a source of reducing power in fermentation or enzymatic reactions and that can use electron mediators and a biocatalyst, such as cells or enzymes, to produce electricity are disclosed. Example electrodes in the system may comprise: (1) neutral red covalently bound to graphite felt; (2) a carboxylated cellulose bound to the graphite felt, neutral red bound to the carboxylated cellulose, NAD+ bound to the graphite felt, and an oxidoreductase (e.g., fumarate reductase) bound to the graphite felt; or (3) a metal ion electron mediator bound to graphite. Various biocatalysts, such as an oxidoreductase, cells of Actinobacillus succinogenes, cells of Escherichia coli, and sewage sludge, are suitable for use in the electrochemical bioreactor system.

Abstract: Disclosed is a biosensor capable of measuring a total concentration of plural types of amino acids. An amino-acid biosensor (200) for measuring a total concentration of a plurality of specific amino acids, comprises a measuring electrode (202) which includes as components a mediator and an enzyme which selectively act on the plurality of specific amino acids each serving as a substrate, and a counter electrode (203). The enzyme has a substrate affinity to each of the plurality of specific amino acids. The enzyme is operable to catalyze a reaction in each of the plurality of specific amino acids as a substrate so as to form a reaction product, and the mediator is operable, during amino-acid concentration measurement, to carry electrons between the reaction product and the measuring electrode.

Abstract: Devices and methods for determining the concentration of an analyte in a sample of liquid are provided.

Abstract: Devices and methods for determining the concentration of an analyte in a sample of liquid are provided.

Abstract: pH-change sensors and related methods are disclosed. One such sensor may have a first ion-sensitive transistor-operational-transconductance-amplifier (the “first IOTA”) and a second ion-sensitive transistor-operational-transconductance-amplifier (the “second IOTA”). Each IOTA may have an ion-sensitive transistor, a load transistor, and an output. In each IOTA, the drain region of the ion-sensitive transistor may be connected to the drain region of the load transistor. A differential sensor may be connected to the IOTAs, and an output from the differential sensor may indicate a voltage difference between the IOTA outputs. The output from the differential sensor may be used to provide an indication of a change in pH.

Abstract: Description is provided herein for an embodiment of a method determining a hematocrit-corrected glucose concentration. The exemplary method includes providing a test strip having a reference electrode and a working electrode, wherein the working electrode includes a plurality of microelectrodes and is coated with at least an enzyme and a mediator.

Abstract: The present invention relates to an analytical instrument (1) which includes a flow path (5) for moving a sample containing blood cells, an introduction port (50) for introducing the sample into the flow path (5), a reagent portion (51) arranged in the flow path (5), and an electron detection medium (52) for obtaining information necessary for analyzing an analysis target component contained in the sample in relation with an amount of electrons transferred. The reagent portion (51) contains an electron mediator for supplying an electron taken from the analysis target component in the sample to the electron detection medium (52), and at least part of the reagent portion is positioned adjacent to the introduction port (50).

Abstract: Provided is a stress measurement kit that is economical and that has good sensitivity. The stress measurement kit for measuring a stress level of a test subject includes: (A) a sensor chip including an electrically insulating substrate, and an electrode system that is placed on the electrically insulating substrate and that includes at least a working electrode and a counter electrode, wherein glucose dehydrogenase (GDH) and an electron mediator are immobilized on the working electrode; (B) a polysaccharide; and (C) a sensor body including an insertion hole into which the sensor chip is inserted, an electrical measurement means that is electrically connected to the electrode system of the sensor chip in a state where the sensor chip is inserted into the insertion hole, and a conversion means by which a current value or an electric quantity measured by the electrical measurement means is converted into an amylase activity value.

Abstract: The present invention provides reagent compositions, and analyte measuring devices and methods that utilize the reagent compositions.

Abstract: A disposable electrochemical sensor strip is provided. The sensor strip includes an isolating sheet having at least a through hole, at least a conductive raw material mounted in the through hole, a metal film covered on the conductive raw material to form an electrode which comprises an electrode working surface for processing an electrode action, and an electrode connecting surface, at least a printed conductive film mounted on the isolating sheet and having a connecting terminal for being electrically connected to the electrode connecting surface, and a signal output terminal for outputting a measured signal produced by the electrode action.

Abstract: Sensors and a method for detecting an analyte are described. Sensors each have a volume of a hydrophilic medium that retains an amount of analyte proportionate to the concentration of analyte in a biological fluid, electrodes and a redox enzyme in contact with medium, and an electron transfer mediator. The fluid contacts sensors and at initially predetermined intervals intermittently applies a potential to electrode sufficient to oxidize the mediator and sensing current through electrode as a function of the duration of the applied potential. The applied mediator oxidizing applied potential is maintained for a period of time sufficient to determine the rate of change of current with time through electrode. The current flow is correlated with the current flow for known concentrations of the analyte in medium.

Abstract: The present invention provides a biosensor that can be used for easy and quick quantitative analysis of a specific component in a sample with high precision and a method for manufacturing such a biosensor. The present invention also provides a biosensor that can be used for a highly precise quantitative analysis after an extended period of storage, specifically, a biosensor with excellent storage stability, and a method for manufacturing such a biosensor. The present invention relates to a biosensor comprising an electrically insulating substrate (1); an electrode (2) having a working electrode (21) and a counter electrode (22) formed on the substrate; and a reaction part (4) that is adhered to one end of the electrode (2); the reaction part (4) being mainly composed of a hydrophilic polymer comprising an oxidoreductase, an electron acceptor, fine crystalline cellulose powder, and hydrophilic and hydrophobic segments.

Abstract: A biosensor for use in determining a concentration of a component in an aqueous liquid sample is provided including: an electrochemical cell having a first electrically resistive substrate having a thin layer of electrically conductive material, a second electrically resistive substrate having a thin layer of electrically conductive material, the substrates being disposed with the electrically conductive materials facing each other and being separated by a sheet including an aperture, the wall of which aperture defines a cell wall and a sample introduction aperture whereby the aqueous liquid sample may be introduced into the cell; and a measuring circuit.