Abstract: An eye-mountable device includes an electrochemical sensor embedded in a polymeric material configured for mounting to a surface of an eye. The electrochemical sensor includes a working electrode, a reference electrode, and a reagent that selectively reacts with an analyte to generate a sensor measurement related to a concentration of the analyte in a fluid to which the eye-mountable device is exposed. The working electrode can have at least one dimension less than 25 micrometers. The reference electrode can have an area at least five times greater than an area of the working electrode. A portion of the polymeric material can surround the working electrode and the reference electrode such that an electrical current conveyed between the working electrode and the reference electrode is passed through the at least partially surrounding portion of the transparent polymeric material.

Abstract: An analyte sensor for the continuous or semi-continuous monitoring of physiological parameters and a method for making the analyte sensor are disclosed. The analyte sensor includes a crosslinked, hydrophilic copolymer sensing layer in contact with a surface of an electrode, where the sensing layer includes methacrylate-derived backbone chains having covalent bonds to an analyte sensing component. The method includes combining the precursor components of the sensing layer, depositing the combined mixture on a surface of an electrode, and curing the deposited mixture.

Abstract: An analyte sensor for the continuous or semi-continuous monitoring of physiological parameters and a method for making the analyte sensor are disclosed. In one aspect, the analyte sensor includes a crosslinked, hydrophilic copolymer in contact with a surface of an electrode, and an analyte sensing component embedded within the crosslinked, hydrophilic copolymer. The crosslinked, hydrophilic copolymer has methacrylate-derived backbone chains of first methacrylate-derived units, second methacrylate-derived units and third methacrylate-derived units. The first and second methacrylate-derived units have side chains that can be the same or different, and the third methacrylate-derived units in different backbone chains are connected by hydrophilic crosslinks.

Abstract: An analyte sensor for the continuous or semi-continuous monitoring of physiological parameters and a method for making the analyte sensor are disclosed. In one aspect, the analyte sensor includes an electrode, a sensing layer in contact with a surface of the electrode, and a protective membrane. The sensing layer is a crosslinked, hydrophilic copolymer including poly(alkylene oxide) and poly(vinyl pyridine), and an analyte sensing component is immobilized within the crosslinked, hydrophilic copolymer. The protective membrane is a crosslinked, hydrophilic copolymer including alkylene oxide, vinyl pyridine and styrene units. The method involves the formation of a sensing layer on a surface of an electrode, followed by the formation of a protective membrane on a surface of the sensing layer.

Abstract: An eye-mountable device includes an electrochemical sensor embedded in a polymeric material configured for mounting to a surface of an eye. The electrochemical sensor includes a working electrode and a reference electrode that reacts with an analyte to generate a sensor measurement related to a concentration of the analyte in a fluid to which the eye-mountable device is exposed. An example assembly process includes: forming a sacrificial layer on a working substrate; forming a first layer of a bio-compatible material on the sacrificial layer; providing an electronics module on the first layer of the bio-compatible material, forming a second layer of the bio-compatible material to cover the electronics module; and annealing the first and second layers of the bio-compatible material together to form an encapsulated structure having the electronics module fully encapsulated by the bio-compatible material.

Abstract: An eye-mountable device includes an electrochemical sensor embedded in a polymeric material configured for mounting to a surface of an eye. The electrochemical sensor includes a working electrode, a reference electrode, and a reagent that selectively reacts with an analyte to generate a sensor measurement related to a concentration of the analyte in a fluid to which the eye-mountable device is exposed. The working electrode can have a first side edge and a second side edge. The reference electrode can be situated such that at least a portion of the first and second side edges of the working electrode are adjacent respective sections of the reference electrode.

Abstract: An eye-mountable device includes an electrochemical sensor embedded in a polymeric material configured for mounting to a surface of an eye. The electrochemical sensor includes a working electrode and a reference electrode that reacts with an analyte to generate a sensor measurement related to a concentration of the analyte in a fluid to which the eye-mountable device is exposed. An example assembly process includes: forming a sacrificial layer on a working substrate; forming a first layer of a bio-compatible material on the sacrificial layer; providing an electronics module on the first layer of the bio-compatible material, forming a second layer of the bio-compatible material to cover the electronics module; and annealing the first and second layers of the bio-compatible material together to form an encapsulated structure having the electronics module fully encapsulated by the bio-compatible material.

Abstract: The present invention relates to improved electrochemical biosensor strips and methods for determining the concentration of an analyte in a sample. By selectively measuring a measurable species residing in a diffusion barrier layer, to the substantial exclusion of the measurable species residing exterior to the diffusion barrier layer, measurement errors introduced by sample constituents, such as red blood cells, and manufacturing variances may be reduced.

Abstract: Disclosed herein is a device that functions as a glucose sensor. The device has a reference electrode; a counter electrode, a working electrode; an electrically conducting membrane; an enzyme layer; a semi-permeable membrane; a first layer of a first hydrogel in operative communication with the working electrode; the first layer of the first hydrogel being operative to store oxygen; wherein the amount of stored oxygen is proportional to the number of freeze-thaw cycles that the hydrogel is subjected to; and a second layer of the second hydrogel. Disclosed too is a method that comprises using periodically biased amperometry towards interrogation of implantable glucose sensors to improve both sensor's sensitivity and linearity while at the same time enable internal calibration against sensor drifts that originate from changes in either electrode activity or membrane permeability as a result of fouling, calcification and/or fibrosis.

Abstract: The present invention pertains to a hemolysis sensor, a hemolysis sensor system and methods of utilizing the hemolysis sensor or hemolysis sensor system to monitor or detect hemolysis in a sample, such as a whole blood sample, a plasma sample, a serum sample or hemolyzed blood. The hemolysis sensor responds to extracellular hemoglobin levels, for example, extracellular hemoglobin in a whole blood sample as a method for detecting hemolysis in whole blood.

Abstract: A glucose sensor suitable for measuring glucose levels in human saliva is provided. Systems containing the glucose sensor and methods for making and using the sensor are also provided. The glucose sensor is highly sensitive and can detect glucose levels at least down to 5 ppm. Fabrication of the sensor involves depositing single-walled carbon nanotubes onto the surface of a working electrode in a 3 electrode electrochemical detector and functionalizing the nanotubes by depositing layers of polymers, metallic nanoparticles, and glucose oxidase enzyme onto the nanotubes. The sensor can be used as a disposable, single-use device or as part of an analytical system, such as a microfluidics system, for the analysis of multiple analytes. The sensor enables the diagnosis and monitoring of diabetes to be performed without pain or the need for finger pricks in a home or clinical setting.

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: Electrochemical sensors for measurement of an analyte comprising an analyte sensing membrane comprising at least one salt of acetate ion, carbonate ion, bicarbonate ion, or mixtures thereof. Sensor testing methods comprising contacting an electrochemical sensor with an aqueous solution comprising at least one salt of acetate ion, carbonate ion, bicarbonate ion, or mixtures thereof and contacting the electrochemical sensor with one or more concentrations of analyte, the one or more concentrations of analyte being in the clinical concentration range of the analyte.

Abstract: A glucose dehydrogenase, having high substrate specificity, can be produced at a low cost, is not affected by oxygen dissolved in a measurement sample and, in particular, has superior thermal stability is obtained by culturing a microorganism belonging to the genus Burkholderia, particularly Burkholderia cepacia. The glucose dehydrogenase produced by the microorganism is collected from the medium and/or from the cells of the microorganism.

Abstract: The present invention provides a biosensor having a code electrode, a method for manufacturing the same, and a method for obtaining sensor information on the same, in which a code electrode for providing sensor information such as correction information, the type of biosensor, etc. is provided in each biosensor such that a measuring device can obtain necessary information on each biosensor from the code electrode, thus solving a variety of conventional problems.

Abstract: A method of measuring an analyte in a biological fluid comprises applying an excitation signal having a DC component and an AC component. The AC and DC responses are measured; a corrected DC response is determined using the AC response; and a concentration of the analyte is determined based upon the corrected DC response. Other methods and devices are disclosed.

Abstract: A biosensor includes a first working electrode that a biocatalyst, which has a property that reacts on a specified ground substance, is disposed, a second working electrode that the biocatalyst, which the property is lost, is disposed, and at least one counter electrode for respectively applying a voltage to the first working electrode and the second working electrode.

Abstract: A biosensor includes a first working electrode that a biocatalyst, which has a property that reacts on a specified ground substance, is disposed, a second working electrode that the biocatalyst, which the property is lost, is disposed, and at least one counter electrode for respectively applying a voltage to the first working electrode and the second working electrode.

Abstract: Embodiments of the invention provide amperometric analyte sensors having optimized elements such as electrodes formed from sputtered platinum compositions as well as layers of material selected to optimize the characteristics of a wide variety of sensor elements and sensors. While embodiments of the innovation can be used in a variety of contexts, typical embodiments of the invention include glucose sensors used in the management of diabetes.

Abstract: A membrane electrode includes a novel sensor combining a filtering function of a membrane and a signal measuring ability of an electrode. A target material may be measured by filtration through the membrane. A small amount of target materials may be detected with high sensitivity using an amplified electrical signal by increasing electrical conductivity by reducing metal ions on the membrane, and thus the target material may be subject to quantitative analysis. In addition, only a target material selectively binding to a receptor may be filtrated by passing a sample through the membrane after a receptor material is fixed to the electrode, and thus may be used to detect an electrical signal. In addition, the sensor may measure a signal in various methods such as electrical conductivity, impedance, etc.

Abstract: An in vivo amperometric sensor is provided for measuring the concentration of an analyte in a body fluid. The sensor comprises a counter electrode and a working electrode, and the working electrode comprises a sensing layer which is generally water permeable and arranged on a support member adjacent to a contact pad. The sensing layer comprises an immobilized enzyme capable of acting catalytically in the presence of the analyte to cause an electrical signal. The sensing layer has an upper surface facing the body fluid and a lower surface facing away from the body fluid, and the immobilized enzyme is distributed within the sensing layer in such a way that the enzyme concentration in the middle between the upper and lower surfaces is at least as high as on the upper surface of the sensing layer.

Abstract: The present invention provides a method of measuring a component in blood, by which the amounts of blood cells and an interfering substance can be measured with high accuracy and high reliability and the amount of the component can be corrected accurately based on the amounts of the blood cells and the interfering substance. In a sensor for measuring a blood component, a first working electrode 13 measures a current that flows during a redox reaction of a blood component, a second working electrode 17 measures the amount of blood cells, and a third working electrode 12 measures the amount of an interfering substance. Next, based on the measurement results, the amount of the blood component to be measured is corrected. Thus, more accurate and precise measurement of the amount of the blood component can be realized.

Abstract: Analyte sensors for determining the concentration of an analyte in a sample. The sensors have a sample chamber having an inlet with a projection extending from an edge of the sensor for facilitating flow of sample into the sample chamber.

Abstract: The present invention discloses a biological test chip and a method for manufacturing the same. The biological test chip comprises a test unit and an auxiliary unit for producing capillary action. The test unit includes a baseboard, at least one pair of electrodes and wires connected to the electrodes that are provided on the baseboard by using printed-circuit-board manufacturing process, and a photoresist layer covering the baseboard. The auxiliary unit includes a double-faced adhesive gel layer and a hydrophilic layer that have at least two thin plates respectively. By utilizing the manufacturing process for a printing circuit board and the photoresist layer, body fluid to be tested can be rapidly drawn in to fill the reaction areas formed in the photoresist layer and thereby can react evenly and rapidly with the reactive enzymes used for the test.

Abstract: The present disclosure relates generally to an electrochemical sensor comprising a membrane layer comprising one or both of an active enzymatic portion and an inactive-enzymatic or non-enzymatic portion, at least one electrode disposed beneath the membrane and either at least one pH sensor or a hematocrit sensor. The present disclosure also relates to methods of adjusting analyte concentration values using a correction factor based on measured pH values and/or measured hematocrit levels.

Abstract: The present disclosure relates generally to an electrochemical sensor comprising a membrane layer comprising one or both of an active enzymatic portion and an inactive-enzymatic or non-enzymatic portion, at least one electrode disposed beneath the membrane and either at least one pH sensor or a hematocrit sensor. The present disclosure also relates to methods of adjusting analyte concentration values using a correction factor based on measured pH values and/or measured hematocrit levels.

Abstract: Selectively permeable membranes for biosensors are provided. In one embodiment, the membrane includes a polymer mixture that includes a polyurethane component, a siloxane component, and a hydrogel component, the components in the mixture in amounts of about 60 to about 80 wt % polyurethane, about 10 to about 20 wt % siloxane, and about 10 to about 20 wt % hydrogel. The membrane has a surface restructured to be hydrophilic, with the restructured surface being crosslinked ed via reactive end groups on at least one of the polyurethane, the siloxane, and the hydrogel components. In another embodiment, the membrane includes a solvent cast film which includes a mixture of a first polyether-based thermoplastic polyurethane copolymer, a polyether-based polyurethane copolymer, and, optionally, a second polyether-based thermoplastic polyurethane copolymer.

Abstract: The invention is directed to enzyme immobilization compositions comprising: one or more enzymes, a humectant, an acrylic-based monomer, a water-soluble organic photo-initiator and a water-soluble acrylic-based cross-linker in a substantially homogeneous aqueous mixture. The invention is also directed to methods for forming sensors comprising such compositions and to apparati for forming arrays of immobilized layers on an array of sensors by dispensing such compositions onto a substrate.

Abstract: The disclosure provides for reagent compositions for biosensors comprising release polymers, methods of making such biosensors and films of reagent compositions comprising release polymers. The reagent compositions comprise a release polymer and an effective analyte detecting amount of an enzyme an enzyme cofactor and a redox compound capable of acting in a biosensor as (i) a redox mediator associated with a working electrode (ii) a redox couple associated with a reference electrode or (iii) the redox mediator associated with the working electrode and the redox couple for the reference electrode.

Abstract: A method of forming an electrochemical test sensor includes providing a base. Electrochemically-active material is placed on the base. Dielectric material is applied over the electrochemically-active material. A first selected area of the dielectric material is laser-ablated to expose the electrochemically-active material. A second selected area of the dielectric material and the electrochemically-active material are laser-ablated to expose the base. The first selected area is different from the second selected area. A second layer is applied to assist in forming a channel in the test sensor. The channel assists in allowing a fluid sample to contact a reagent located therein. The dielectric material is located between the base and the second layer.

Abstract: A sensor for continuous detection of one or more analytes in a liquid flow, comprising an array of electrodes together forming an essentially planar sensing surface and a flow distributor with a flow inlet a flow channel and a flow outlet in order to establish a liquid flow of analytes along the sensing surface. The flow inlet and the flow outlet are located in a plane different to the plane of the sensing surface. The array of electrodes is arranged so that, in the direction from the flow inlet to the flow outlet, the array of electrodes consecutively comprises a first blank electrode, at least one measuring electrode, a second blank electrode, at least one measuring electrode and optionally a third blank electrode.

Abstract: The present invention relates to an analyzer (1) to be used with an analytical tool (2) mounted thereto and used for analyzing a particular component contained in a sample supplied to the analytical tool (2). The analyzer (1) includes at least one detection terminal pair (11, 12) including a first and a second detection terminals (11A, 11B, 12A, 12B) which are capable of selecting a mutually contacting state and a non-contacting state, a detector (15) for detecting the state of contact of the first and the second detection terminals (11A, 11B, 12A, 12B), and an abnormality detector (16) for detecting an abnormality of the at least one detection terminal pair (11, 12) based on the detection result by the detector (15).

Abstract: The present invention discloses an enzyme electrode and its producing method, which comprises: providing a substrate with a carbon surface; forming a gold surface on the carbon surface and thus forming an electrode; covalently bonding a mediator containing an aldehyde group to the electrode; and covalently bonding a glucose oxidase to the electrode.

Abstract: A reactive oxygen species measuring device according to the present invention comprises a reactive oxygen species sensor provided with an electrode assembly capable of detecting the presence of reactive oxygen species or the like in terms of an electric current, a power source means for applying a measuring voltage to the reactive oxygen species sensor, and a reactive oxygen species concentration measuring means for measuring a concentration of the reactive oxygen species or the like from the current detected by the reactive oxygen species sensor. According to the present invention, a concentration of reactive oxygen species or the like such as in vivo or in vitro superoxide anion radical (O2?.) can be measured reliably, and the entire device can be formed in a smaller size and always mounted to a living body.

Abstract: In vitro electrochemical sensor that provide accurate and repeatable analysis of a sample of biological fluid are provided. In some embodiments, the sensors have a measurement zone that has a volume less than the volume of the sample chamber. The measurement zone could have a volume of no more than about 0.2 ?L.

Abstract: A method for monitoring a select analyte in a sample in an electrochemical system. The method includes applying to the electrochemical system a time-varying potential superimposed on a DC potential to generate a signal; and discerning from the signal a contribution from the select analyte by resolving an estimation equation based on a Faradaic signal component and a nonfaradaic signal component.

Abstract: The present invention provides an electrochemical sensor having a sensing chemistry that operates substantially free of any “oxygen effect”. The electrochemical sensors are useful in determining the level of an analyte in a biological sample from a subject. The present invention also provides sensor assemblies including the electrochemical sensors as well as methods of using the same.

Abstract: Electrochemical test cells are made with precision and accuracy by adhering an electrically resistive sheet having a bound opening to a first electrically conductive sheet. A notching opening is then punched through the electrically resistive sheet and the first electrically conductive sheet. The notching opening intersects the first bound opening in the electrically resistive sheet, and transforms the first bound opening into a notch in the electrically resistive sheet. A second electrically conductive sheet is punched to have a notching opening corresponding to that of first electrically conductive sheet, and this is adhered to the other side of the electrically resistive sheet such that the notching openings are aligned. This structure is cleaved from surrounding material to form an electrochemical cell that has a sample space for receiving a sample defined by the first and second conductive sheets and the notch in the electrically resistive sheet.

Abstract: The disclosure provides for reagent compositions for biosensors comprising release polymers, methods of making such biosensors and films of reagent compositions comprising release polymers. The reagent compositions comprise a release polymer and an effective analyte detecting amount of an enzyme an enzyme cofactor and a redox compound capable of acting in a biosensor as (i) a redox mediator associated with a working electrode (ii) a redox couple associated with a reference electrode or (iii) the redox mediator associated with the working electrode and the redox couple for the reference electrode.

Abstract: A method for operating a measuring meter for an electrochemical test strip is provided. The method comprises steps of applying a voltage to electrodes of the test strip at least during one of a sample presence detection period and an incubation period; and repeatedly increasing and decreasing the voltage during at least one of the sample presence detection period and the incubation period.

Abstract: An immobilization carrier containing an electron acceptor compound is used in addition to glutaraldehyde and poly-L-lysine to immobilize an enzyme and an electron acceptor compound simultaneously to an electrode. For example, here are used diaphorase as the enzyme and 2-amino-3-carboxy-1, 4-naphthoquinone (ACNQ) as the electron acceptor compound.

Abstract: Embodiments of the invention provide amperometric analyte sensors having optimized elements such as electrodes formed from sputtered platinum compositions as well as layers of material selected to optimize the characteristics of a wide variety of sensor elements and sensors. While embodiments of the innovation can be used in a variety of contexts, typical embodiments of the invention include glucose sensors used in the management of diabetes.

Abstract: The invention relates to a method for calibrating an analyte-measurement device that is used to evaluate a concentration of analyte in bodily fluid at or from a measurement site in a body. The method involves measuring a concentration, or calibration concentration, of an analyte in blood from an “off-finger” calibration site, and calibrating the analyte-measurement device based on that calibration concentration. The invention also relates to a device, system, or kit for measuring a concentration of an analyte in a body, which employs a calibration device for adjusting analyte concentration measured in bodily fluid based on an analyte concentration measured in blood from an “off-finger” calibration site.

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: Measurement of the series track resistance of a working and counter electrode pair in an electrochemical test strip provide error detection for multiple variations in the quality of the test strip, as well as the operation of strip in the test meter. In particular, a single measurement of series resistance can be used to detect and generate an error message when an incorrect reading is likely to result due to (1) damaged electrode tracks, (2) fouled electrode surfaces, (3) dirty strip contacts, or (4) short circuit between the electrodes.

Abstract: A BUN (blood urea nitrogen) sensor containing immobilized carbonic anhydrase and immobilized urease for the in vitro detection of urea nitrogen in blood and biological samples with improved performance and precision characteristics.

Abstract: An enzyme electrode and its producing method are disclosed. The method includes providing a substrate having a carbon surface; forming a gold surface on the carbon surface and forming an electrode; modifying the gold surface by L-cysteine; modifying the gold surface by N,N?-dicyclohexylcarbodiimide; and chemically bonding the modified gold surface with a glucose oxidase.

Abstract: A method of electrochemical analysis using a sensor electrode specific for an analyte under test. The method comprises immersing the sensor electrode in a sample solution suspected of containing the analyte; forming an electrochemically active complex by exposure to solutions containing secondary receptors or competing molecules labelled with a charged or enzyme label; and subsequently exposing the sensor to an electrochemically active solution. The measurement step comprises driving the sensor electrode potential to a predetermined fixed potential by applying a current or activation waveform then monitoring the potential difference between the sensor electrode and a reference electrode following removal of the holding current. Current, rate and potential can all be measured and used to determine analyte concentration or sensor state.

Abstract: According to an embodiment of the invention, a method of determining hydration of a sensor having a plurality of electrodes is disclosed. In particular embodiments, the method couples a sensor electronics device to the sensor and measures the open circuit potential between at least two of the plurality of electrodes. Then, the open circuit potential measurement is compared to a predetermined value. In some embodiments, the plurality of electrodes includes a working electrode, a reference electrode, and a counter electrode. In still further embodiments, the open circuit potential between the working electrode and the reference electrode is measured. In other embodiments, the open circuit potential between the working electrode and the counter electrode is measured. In still other embodiments, the open circuit potential between the counter electrode and the reference electrode is measured.

Abstract: The present invention relates generally to systems and methods for improved electrochemical measurement of analytes. The preferred embodiments employ electrode systems including an analyte-measuring electrode for measuring the analyte or the product of an enzyme reaction with the analyte and an auxiliary electrode configured to generate oxygen and/or reduce electrochemical interferants. Oxygen generation by the auxiliary electrode advantageously improves oxygen availability to the enzyme and/or counter electrode; thereby enabling the electrochemical sensors of the preferred embodiments to function even during ischemic conditions. Interferant modification by the auxiliary electrode advantageously renders them substantially non-reactive at the analyte-measuring electrode, thereby reducing or eliminating inaccuracies in the analyte signal due to electrochemical interferants.