Abstract: A method of depositing reagent on an electrochemical test sensor adapted to determine information relating to an analyte includes providing a base and forming an electrode pattern on the base. The method further includes depositing the reagent on at least the electrode pattern using a reagent-dispensing system. The reagent-dispensing system applies mechanical force to the reagent in the reagent-dispensing system to assist in providing a wet reagent droplet on at least the electrode pattern.

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 biosensor comprises a substrate; a reference electrode; a working electrode; a counter electrode; and a plurality of permeability adjusting spacers. The reference electrode, the working electrode and the plurality of permeability adjusting spacers are all being disposed to be substantially parallel to each other to create a plurality of enzyme containing porous sections. The enzyme containing porous sections contain an enzyme; where the enzyme is operative to react with a metabolite to determine the concentration of the metabolite. By combining a number of the aforementioned biosensors, the differential concentration of a target enzyme or protein is determined by monitoring the changes on its metabolite substrates.

Abstract: Contemplated methods and devices comprise performing electrochemical sample analysis in a multiplexed electrochemical detector having reduced electrical cross-talk. The electrochemical detector includes electrodes that share a common lead from a plurality of leads. The sample, which may be a liquid sample, is introduced into one or more sample wells and a signal is applied to at least one of the electrodes. A response signal is measured while simultaneously applying a substantially fixed potential to each of a remainder of the plurality of leads.

Abstract: The invention disclosed herein includes sensors having three dimensional configurations that allow expansive “360°” sensing (i.e. sensing analyte from multiple directions) in the environments in which such sensors are disposed. Embodiments of the invention provide analyte sensors having foldable substrates adapted to produce optimized configurations of electrode elements as well as methods for making and using such sensors. Typical embodiments of the invention include glucose sensors used in the management of diabetes.

Abstract: An embodiment of the invention provides an ultrasensitive and selective system and method for detecting reactants of the chemical reaction catalyzed by an oxidoreductase, such as glucose and ethanol, at a concentration level down to zepto molar (10?21 M). In embodiments, the invention provides a cyclic voltammetry system comprising a working electrode, an oxidoreductase, and an electric field generator, wherein the oxidoreductase is immobilized on the working electrode; and the electric field generator generates an electric field that permeates at least a portion of the interface between the oxidoreductase and the working electrode. The ultrasensitivity of the system and method is believed to be caused by that the electrical field enhances quantum mechanical tunneling effect in the interface, and therefore facilitates the interfacial electron transfer between the oxidoreductase and the working electrode.

Abstract: A system for testing for analytes in a sample of biological fluid includes a test strip that defines a cavity for receiving the sample. At least two sets of electrodes are adjacent the sample cavity, including one for measuring one property of the sample, and another for measuring one or more other properties of the sample, such as temperature and/or the presence or magnitude of confounding variables. The measurements are combined to yield the desired result. At least one set of working and counter electrodes each have a plurality of elongated “fingers” interdigitated with those of the other electrode in the set. The gaps between fingers can be quite small, so that the two electrode sets together can operate in a small measurement volume of sample. Additional electrodes can be included that measure the presence or sufficiency of the sample, and additional traces on the strip can act as configuration identifiers.

Abstract: A nicotinamide adenine dinucleotide (NAD) polymeric coenzyme for use in enzymatic electrochemical-based sensors includes NAD moieties covalently bound as pendent groups to a polymer backbone. An enzymatic electrochemical-based biosensor includes nicotinamide adenine dinucleotide (NAD) polymeric coenzyme, a polymeric electron transfer agent (e.g., polymeric ferrocene) at least one working electrode, and at least one reference electrode.

Abstract: The invention relates to a biopile electrode or biosensor electrode intended to be immersed in a liquid medium containing a target and an oxidizer, respectively a reducer, in which the anode comprises an enzyme able to catalyse the oxidation of a target, and the cathode comprises an enzyme able to catalyse the reduction of the oxidizer, and in which each of the anode electrode and cathode electrode consists of a solid agglomeration of carbon nanotubes mixed with the enzyme, and is secured to an electrode wire

Abstract: An object of the present invention is to provide an electrode for an electrochemical measurement apparatus that is less susceptible to influence from interference substances as compared to conventional technology and an electrochemical measurement apparatus using such an electrode. A working electrode 9 (an electrode 1 for an electrochemical measurement apparatus) used in an electrochemical measurement apparatus 3 of the present invention uses an alloy containing iridium and rhenium with such a composition that selectivity for hydrogen peroxide can be obtained.

Abstract: A biosensor includes a working electrode 101, a counter electrode 102 opposing the working electrode 101, a working electrode terminal 103 and a working electrode reference terminal 10 connected to the working electrode 101 by wires, and a counter electrode terminal 104 connected to the counter electrode 102 by a wire. By employing a structure with at least three electrodes, it is possible to assay a target substance without being influenced by the line resistance on the working electrode side.

Abstract: There is provided by this invention a simple and rapid amperometric biosensor for determining the level of histamine in seafood or fish. The biosensor combines the technology of screen-printing with immobilized diamine oxidase as the bioreceptor. IQ one embodiment of the present invention, the biosensor incorporates potassium hexacyanoferrate (III) as a mediator.

Abstract: The present disclosure provides for a biosensor comprising a graphene electrode linked to a biosensing element by a linker, the biosensing element bonded to a flexible substrate. The graphene electrode has a first end and a second end, such that the first end may be a positive terminal and the second end a negative terminal. An electrical voltage may be applied to the positive and negative terminals to measure an electrical current response in proportion to a lactate concentration on the biosensing element. In embodiments, the biosensing element is an enzyme. By way of example, the biosensing element may be LOD.

Abstract: A fusion protein of pyrroloquinoline quinone glucose dehydrogenase (PQQGDH) and a cytochrome is disclosed. PQQGDH is, for example, a water-soluble PQQGDH derived from Acinetobacter calcoaceticus. The cytochrome is, for example, an electron transfer domain of quinohemoprotein ethanol dehydrogenase from Comamonas testosteroni. The fusion protein of the present invention shows intramolecular electron transfer from PQQ, a redox center, to the cytochrome, which allow construction of a direct electron transfer-type glucose sensor which requires no electron mediators.

Abstract: A chemistry matrix for use in determining the concentration of an analyte in a biological fluid includes a glucose dehydrogenase, nicotinamide adenine dinucleotide, an alkylphenazine quaternary salt, and/or a nitrosoaniline. The chemistry matrix is used with an electrochemical biosensor to determine the concentration of an analyte after a reaction occurs within the biosensor, at which time an analysis is completed to determine the concentration. A method of determining the concentration of an analyte using the chemistry matrix of glucose dehydrogenase, nicotinamide adenine dinucleotide, an alkylphenazine quaternary salt, and/or a nitrosoaniline is another aspect that is described. The method also further features test times of five seconds or less. Methods utilizing the new chemistry matrix can readily determine an analyte such as blood glucose at concentrations of from about 20-600 mg/dL at a pH of from about 6.5 to about 8.5.

Abstract: This invention provides a substrate concentration measuring method for measuring a concentration of a substrate included in a specimen based on an output for measurement from an enzyme electrode when the enzyme electrode and the substrate are reacted with each other, the substrate concentration is calculated using an output for correction from the enzyme electrode obtained when a reference solution whose substrate concentration is known and the enzyme electrode are reacted with each other before or after the enzyme electrode and the substrate are reacted with each other. For example, the output for correction is measured by each specimen. In this method, the substrate concentration may be calculated using the output for correction for the specimen to be measured and an output for correction corresponding to the at least one other specimen and measured prior to the output for correction.

Abstract: Methods and devices for determining the concentration of a constituent in a physiological sample are provided. The blood sample is introduced into a test strip with portions of the blood sample being directed to both a first capillary and a second capillary. The first capillary configured to electrochemically determine a concentration of a first analyte in a blood sample by measuring a signal across a set of electrodes. The second capillary is configured to determine a hematocrit value of the blood sample by measuring a signal across a second set of electrodes.

Abstract: A sensor system, device, and methods for determining the concentration of an analyte in a sample is described. Gated voltammetric pulse sequences including multiple duty cycles of sequential excitations and relaxations may provide a shorter analysis time and/or improve the accuracy and/or precision of the analysis. The disclosed pulse sequences may reduce analysis errors arising from the hematocrit effect, variance in cap-gap volumes, non-steady-state conditions, mediator background, a single set of calibration constants, under-fill, and changes in the active ionizing agent content of the sensor strip.

Abstract: The present invention is directed to the detection of target analytes using electronic techniques, particularly AC techniques.

Abstract: An objective of the present invention is to establish a technique for making it possible to immobilize an enzyme on an electrically conductive base material in a uniformly, high density, and constantly aligned orientation, for the purpose of constructing an enzyme electrode having improved electrode performance. An electrode having enzyme crystals immobilized thereon, the electrode being provided with an electrically conductive base material that can be connected to an external circuit and enzyme crystals that serve as an electrode catalyst, wherein the enzyme crystals are immobilized on the electrically conducive base material; a method for producing an electrode having enzyme crystals immobilized thereon; and a biological fuel cell and a biosensor which are provided with an electrode having enzyme crystals immobilized thereon.

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: An electrochemical detection system having a disposable cartridge capable of performing a plurality of assay protocols is disclosed. The cartridge includes a blister pack for the long-term storage and controlled release of multiple reagents. The blister pack is bonded to and operatively associated with a fluidic backbone for providing the fluid pathways, storage capacity, and fluid control functions for performing multiple assay protocols. The cartridge further includes a plurality of sensors having a multiple electrode arrangement in operative association with a respective flow cell defined by the fluidic backbone. After the user has transferred a sample into the cartridge and engaged the cartridge to the reader, the reader operatively interfaces with the cartridge such that different assay protocols may be simultaneously performed in isolation from one another inside the cartridge. The reader may be one of many readers that operatively communicate data to a remote server for processing.

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: A biosensor for measuring an analyte in a liquid sample includes a working electrode having a dispensed reagent thereon wherein the dispensed reagent contains an enzyme capable of catalyzing a reaction involving the analyte, a mediator that is considered an enzyme inhibitor, and an enzyme co-factor where the working electrode provides a stable and sensitive response even when the biosensor is stored at ambient conditions for a period of time selected from the group consisting of at least 3 months, 12 months and two years or more.

Abstract: A biosensor according to the present invention includes a first base material having an insulating surface; an adhesive layer located on the insulating surface of the first base material; and an electrode system and wiring sections fixed to the first base material via the adhesive layer. The electrode system includes top electrode layers and bottom electrode layers, and the bottom electrode layers are formed of a material having a higher conductivity than that of the top electrode layers; the electrode system includes a working electrode and a counter electrode, and also includes an enzyme reaction section located on the working electrode, the enzyme reaction section containing an enzyme and an electron acceptor; and the bottom electrode layers and the wiring sections are integral with each other.

Abstract: In one form, a mutant fructosyl amino acid oxidase modified at an amino acid residue involved in a proton relay system is provided. The mutant fructosyl amino acid oxidase has reduced oxidase activity while substantially maintaining its dehydrogenase activity. Other forms include an assay device and assay method for measuring glycated protein. Still, other forms include unique methods, techniques, systems and devices involving a mutant fructosyl amino acid oxidase.

Abstract: Enzyme based analyte sensors having radiation stabilizing agents are disclosed and described. More particularly, devices comprising a radiation stabilizing agent and methods for stabilizing sensors to high energy radiation sterilization are disclosed and described.

Abstract: A biosensor system for determining the concentration of an analyte in a sample includes a plurality of test sensors, and includes a container including a desiccant and the plurality of test sensors, sealed in the container. When the container is stored for two weeks at a temperature of 50° C., and each test sensor is subsequently removed from the container, connected through the at least two conductors to a measurement device and then contacted with one of a plurality of samples including an analyte, where the plurality of samples has analyte concentrations that span the range of 50 mg/dL-600 mg/dL, and the analyte concentration in each sample is determined by the test sensor and the measuring device, the bias of each determined analyte concentration may be within ±10 mg/dL or ±10%, and the coefficient of variation of the determined analyte concentrations may be at most 2.5%.

Abstract: A sample receiving chip comprising a substrate that receives an aliquot volume of a sample fluid and a sample region of the substrate, sized such that the volume of the sample fluid is sufficient to operatively cover a portion of the sample region. The energy imparted into the sample fluid is transduced by the sample region to produce an output signal that indicates energy properties of the sample fluid. The sample receiving chip also includes a channel formed in the substrate, the channel configured to collect the aliquot volume of a sample fluid and transfer the aliquot volume of sample fluid to the sample region.

Abstract: The present invention is broadly concerned with the crafting and manufacturability of an implantable enzymatic-based sensor characterized by a small size, optimum geometry, linearity of response over the concentration range of interest, extended shelf-life, selectivity for the analyte in question, and the ability to exclude bioactive interferents. More particularly, it is preferably concerned with a general approach to optimize the performance of the biorecognition elements required to produce biosensors of the type designed to provide, and in conjunction with a suitable signal processing unit, a current which is proportional to the concentration of the analyte of interest. The biosensors described herein may be implanted in vivo, including intra-cerebral, sub-cutaneous, intra-muscular, inter-peritoneal oral, serum, and vascular implantation, the majority of which may act as a surrogate for systemic monitoring and used to monitor analytes of interest in real-time.

Abstract: Disclosed is a modified glucose dehydrogenases that has dramatically increased productivity in Escherichia coli and dramatically increased thermal stability, which is obtained by introducing specific amino acid mutations to glucose dehydrogenase derived from Botryotinia fuckeliana. Also disclosed is a modified glucose dehydrogenases that has dramatically increased productivity in E. coli and dramatically increased thermal stability, which is obtained by replacing two amino acid residues in glucose dehydrogenase of fungal origin with cysteine residues. The novel glucose dehydrogenase has a low reactivity to xylose.

Abstract: In a biosensor that detects introduction of a sample liquid into a specimen supply path using a detecting electrode, a means of improving accuracy of detection is provided. The biosensor has: an electrode system including measuring electrode, counter electrode, and detecting electrode on first electrically insulating support; specimen supply path for introducing the sample liquid; and reagent layer used for quantifying a substrate contained in the sample liquid. The means is characterized in that detecting electrode is spaced from measuring electrode by a distance sufficient for the sample liquid to sufficiently cover measuring electrode before the sample liquid reaches detecting electrode.

Abstract: The present invention provides: a reagent composition having higher storage stability; a sensor involving the reagent composition; and others. According to the present invention, a specific heterocyclic compound is added to a reagent composition to improve the storage stability of the reagent composition and reduce the degree of fluctuation in current values in a sensor that utilizes reagent composition.

Abstract: A microfluidic device includes a micro-channel that defines a plane. A plurality of drive electrodes is located on a first side of the plane. At least one ground electrode is operable to establish an electric potential with the plurality of drive electrodes. An array of electrochemical biosensors is located on a second, opposite side of the plane.

Abstract: The present invention relates to a device for sensing a target chemical. The device includes a flexible, non-planar substrate; a printed, solid-state sensing element comprising a chemical sensing material which produces an electrical signal upon interaction with the target chemical; a first printed electrode comprising a first conductive composition; and a second electrode comprising a second conductive composition. The first and second electrodes are electrically isolated from one another, and one or both of the first and second electrodes is in electrical contact with said sensing element. The first and second electrodes and the sensing element collectively form an electrochemical sensor which is coupled to the flexible, non-planar substrate. Medical devices comprising the device of the present invention and methods of making a device for sensing a target chemical are also disclosed.

Abstract: Methods and systems for measuring the concentration of an analyte in a blood sample and, more particularly, to methods of chemistry patterning reagent layers for multiple well biosensors. A first capillary is first configured to receive a dispensed reagent layer such that the reagent layer is distributed in a substantially uniform manner within the first capillary. The first capillary may also configured to isolate the first capillary from other capillaries present in the biosensor. After the reagent layer has been dispensed and dried, the first capillary may then be reconfigured to allow the first capillary to receive a blood sample.

Abstract: An electrochemical device for determining the percentage of glycated hemoglobin in a blood sample is provided. The device includes a cathode and anode and one or more cells. The device may include an enzyme capable of reducing oxygen to water for determining the total amount of hemoglobin in a sample by electrochemically measuring, in an oxygen electroreduction reaction at a cathode, the amount of oxygen in the sample. The device may also be used to determine the amount of glycated hemoglobin in the sample (e.g., spectrometrically or electrochemically). Also provided are devices that include glycated hemoglobin hydrolysis agents or glycated hemoglobin separating agents.

Abstract: Techniques and systems are disclosed for implementing textile-based screen-printed amperometric or potentiometric sensors. The chemical sensor can include carbon based electrodes to detect at least one of NADH, hydrogen peroxide, potassium ferrocyanide, TNT or DNT, in liquid or vapor phase. In one application, underwater presence of chemicals such as heavy metals and explosives is detected using the textile-based sensors.

Abstract: A method of forming a 3-phenylimino-3H-phenothiazine or a 3-phenylimino-3H-phenoxazine mediator includes providing a first reactant including phenothiazine or phenoxazine, providing a first solvent, providing a second reactant and providing a second solvent. The first reactant, first solvent, second reactant and second solvent are combined to form a reactants solution. Sodium persulfate is added to the reactants solution to couple the first and second reactants resulting in a reaction solution including the 3-phenylimino-3H-phenothiazine or the 3-phenylimino-3H-phenoxazine mediator.

Abstract: Polymers for use as redox mediators in electrochemical biosensors are described. The transition metal complexes attached to polymeric backbones 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.

Abstract: Depletion of an analyte on a surface of an electrode is restrained by increasing a quantity of supply of the analyte to the surface of the electrode. An electrochemical sensor includes a substrate, an electrode provided on the substrate, an external layer film provided on the substrate to cover the electrode, and a groove formed in at least a part of the substrate in a direction of the electrode of the substrate.

Abstract: Provided is a moisture detection device including: a moisture detection label that has at least a pair of detection terminals and a pattern, the detection terminals being provided on a base material with an insulated front surface, the pattern being provided on the surface of the base material and formed between the detection terminals with water-dispersible and conductive paint; and detection circuit which detects an electrical connection state between the detection terminals.

Abstract: A method and device are provided for measuring a level of a clinically relevant analyte (such as glucose) in a fluid (such as blood). The device includes a flow path for conducting said fluid through the device; a detection chamber arranged on said flow path; and detector means arranged to detect analyte levels in the fluid in said chamber, wherein: said detection chamber contains a predetermined amount of an analyte such that that analyte mixes with fluid in the detection chamber to form, at the detector means, a calibration sample of the fluid at a time after the arrival of the fluid in said detection chamber, and said detector means is arranged to detect a first analyte level of an unadulterated sample of the fluid at a first time which is before the formation of said calibration sample and to detect a second analyte level of said calibration sample at a second time which is after the formation of said calibration sample.

Abstract: The invention relates to novel compositions of 1,3-disubstituted ferrocenes useful for the modification of electrodes.

Abstract: A chemical composite useful for preparing a bioelectronic device includes a biologically active compound, such as an enzyme, that is bound directly or indirectly to a polyelectrolyte, which can be reversibly coupled to a chemically treated electrically conductive substrate by electrostatic forces to provide biomimetic sensors, catalyst systems, and other devices having an electrode that can be regenerated and reused. Required or desired cofactors, mediators or the like may be incorporated into the devices, typically by bonding them to the treated substrate and/or the polyelectrolyte.

Abstract: Glucose and ATP biosensors have important applications in diagnostics and research. Combining single-walled carbon nanotubes (SWCNTs) with Pt nanoparticles can significantly enhance the performance of electrochemical biosensors. This disclosure illustrates the use of single-stranded DNA (ssDNA) to modify SWCNTs to increase SWCNT solubility in water. Multiple embodiments with this configuration allows for exploration of new schemes of combining ssDNASWCNT and Pt black in aqueous media systems. These embodiments resulted in a nanocomposite with enhanced biosensor performance. The ssDNA-SWCNT/Pt black nanocomposite constructed by a layered scheme proved most effective in terms of biosensor activity. The key feature of this structure and method of use is the exploitation of ssDNASWCNTs as molecular templates for Pt black electrodeposition. Glucose and ATP microbiosensors fabricated utilizing this structure and method of use exhibited high sensitivity, wide linear range and low limit of detection.

Abstract: A modified pyrroloquinoline quinone glucose dehydrogenase that exhibits a high selectivity for glucose is provided. A modified pyrroloquinoline quinone glucose dehydrogenase is disclosed in which the amino acid residue G at Position 99 of a pyrroloquinoline quinone glucose dehydrogenase (PQQGDH) represented by SEQ ID NO: 1, or the amino acid residue G at Position 100 of the pyrroloquinoline quinone glucose dehydrogenase (PQQGDH) represented by SEQ ID NO: 3, is substituted by the amino acid sequence TGZN (where Z is SX, S, or N and X is any amino acid residue). The modified PQQGDH of the present invention may additionally comprise one or more mutations selected from the group consisting of Q192G, Q192A, or Q192S; L193X; E277X; A318X; Y367A, Y367F, or Y367W; G451C; and N452X (where X is any amino acid residue).

Abstract: The disclosure also relates to novel compositions and methods for the single, direct detection of Hemoglobin A1c percentage in a sample, using conversion of functional groups attached to a transitional metal complex, resulting in quantifiable electrochemical signal at two unique potentials, Eo1 and Eo2.

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: The present invention relates to technology for constructing a reaction system including a test target, an oxidation-reduction enzyme, and an electron mediator, and measuring the concentration of the test target by an electrochemical process. A Ru compound is used as the electron mediator. The present invention provides a concentration test instrument including a substrate, first and second electrodes formed on the substrate, and a reagent layer formed as a solid. The reagent layer contains an oxidation-reduction enzyme and a Ru compound, and is constituted so as to dissolve and construct a liquid phase reaction system when a sample liquid is supplied.