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: A biosensor for determining the concentration of an analyte in a biological sample. The biosensor comprises a support, a reference electrode or a counter electrode or both disposed on the support, a working electrode disposed on the support, the working electrode spaced apart from the other electrode or electrodes on the support, a covering layer defining a sample chamber over the electrodes, an aperture in the covering layer for receiving a sample, and at least one layer of mesh in the sample chamber between the covering layer and the electrodes. The at least one layer of mesh has coated thereon a silicone surfactant. Certain silicone surfactants are as effective as fluorinated surfactants with respect to performance of biosensors. These surfactants, when coated onto the mesh layer of the biosensor, are effective in facilitating the transport of aqueous test samples, such as blood, in the sample chamber.

Abstract: A porous electroconductive material is provided. The electroconductive material enables efficient enzymatic metabolic reactions on electrodes and yields electrodes having immobilized enzymes thereon which remain stable in any working environment. The porous electroconductive material, which has a three-dimensional network structure, is formed from a skeleton of porous material and a carbonaceous material covering the surface of the skeleton. The porous material constituting the skeleton is foamed metal or alloy. This porous electroconductive material is made into an electrode, and enzymes are immobilized on this electrode. The resulting electrode with immobilized enzymes thereon is used as the anode of a bio-fuel cell.

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 device for sampling liquid samples is provided comprising a capillary-active channel, a sampling site, and a determination site. The capillary-active channel is configured for transporting a sample from the sampling site to the determination site. The capillary-active channel is substantially formed by a carrier, a cover and an intermediate layer located between the carrier and cover. The carrier protrudes beyond the cover in the area of the sampling site. The intermediate layer is displaced towards the back in the direction of the determination site in the area of the sampling site so that the carrier as well as the cover protrude beyond the intermediate layer. The device allows sample to be applied from above onto the exposed area of the carrier in the area of the sampling site and also allows sample to be applied from the side.

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: 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: A system for in situ monitoring within a specified environment includes a housing with an intake inserted into the environment. A plurality of pumps are included in the housing with a number of test beds, each being separately coupled to one of the number of pumps, where each of the number of test beds holds material and where each of the plurality of pumps operate to separately push fluid through a coupled test bed. An effluent storage device is disposed to receive effluent from the number of test beds.

Abstract: Disclosed are an electrochemical biosensor which comprises a production lot information identification portion, on which information is recorded in a magnetization mark, and a measuring device which can automatically identify the production lot information of the biosensor with the insertion of the electrochemical biosensor into the measuring device. The electrochemical biosensor and the measuring device thereof can record production lot information in the form of magnetization marks on an electrochemical biosensor strip and read the information as digital signals through a magnetoresistance sensor device, which can be mounted on the surface of a circuit board using Surface Mounted Technology (SMT). Without the need for a high-priced filter or a complicated calculation system, the magnetic detector system has a simple construction and realizes economic efficiency in the construction of the measuring device.

Abstract: The present invention discloses a biosensor strip, which comprises: a base plate layer defining a first strip end and a second strip end; a conductive layer being disposed on the base plate layer and partitioned into at least two electrode paths; a reagent containing layer being disposed on the conductive layer and comprising a first through hole that is located at the first strip end and for accommodating a reagent solution, wherein the reagent solution comprises matrix, redox mediator, enzyme, surfactant, and a buffer solution; a channel forming layer being disposed on the reagent containing layer and comprising a gap portion that is located at the first strip end; and a cover layer being disposed on the channel forming layer and comprising a second through hole that exposes the partial area of the gap portion of the channel forming layer.

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.

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 practical measuring device and a measuring method that allow simply measuring average postprandial blood glucose from urinary glucose. The blood glucose measuring device includes a measuring unit that measures postprandial urinary glucose from subject's urine at a predetermined time after meal, a processing unit that calculates average postprandial blood glucose through a period up to the predetermined time after meal, based on the postprandial urinary glucose, a storage unit that stores calibration data including the postprandial urinary glucose and the average postprandial blood glucose in association, and an output unit that outputs data indicating the calculated average postprandial blood glucose. The processing unit calculates the average postprandial blood glucose, based on the postprandial urinary glucose from the urine of the subject who has intaken a desired amount of water or perspired in the period up to the predetermined time after meal, and the calibration data.

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: 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: An amperometric biosensor is provided for determination of creatinine in a sample fluid. The biosensor can be an enzyme-polymer composition having at least one redox polymer and a plurality of enzymes immobilized on an electrode surface. Methods of preparing the amperometric biosensor are included. In addition, methods and systems using the amperometric biosensor in measuring creatinine concentrations of a patient and treatments of a patient with monitoring of the progress of dialysis performed on the patient are also provided.

Abstract: A test strip with a sample receiving chamber having a novel flared portion that terminates in a sample receiving opening. The flared portion provides a reservoir from which sample fluid can be drawn into the capillary or sample receiving chamber. The wider opening provided by the present invention is easier to “target” with a sample fluid. In preferred embodiments, the hydrophilic reagent layer extends to the dosing end or side of the test strip and further promotes wicking of the sample into the sample receiving chamber and thus reduces dose hesitation. In other preferred embodiments, a tapered dosing end is provided on the test strip in combination with the flared portion, and this combination create a test strip that will draw sample fluid into the sample receiving chamber regardless of where along the dosing edge of the test strip the fluid sample makes contact.

Abstract: The present invention provides a test strip for measuring a concentration of an analyte of interest in a biological fluid, wherein the test strip may be encoded with information that can be read by a test meter into which the test strip is inserted.

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 easily manufactured electrochemical test strip is made with facing electrode but side by side connectors for insertion into an electrochemical test meter. Current is conducted from the electrode on one layer to a connector on the other by a conductive layer disposed adjacent the end of a spacer layer, or by displacing the layer to bring a conductive surface on it into contact with the connector.

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: Subsystems and methods for use in patch clamp systems are provided. For example, in certain embodiments, compensation circuitry is used to compensate for non-idealities present in the patch clamp system. The accuracy of this compensation may be verified by employing, for example, circuitry that models the patch clamp system.

Abstract: Plasmons on a waveguide may deliver energy to photocatalyze a reaction. The waveguide or other energy carrier may be configured to carry electromagnetic energy and generate plasmon energy at one or more locations proximate to the waveguide, where the plasmon energy may react chemically with a medium or interaction material.

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: A method and system that enables a user to maintain a sensor in real time. The present invention involves performing a diagnostic Electrochemical Impedance Spectroscopy (EIS) procedure to measure sensor impedance value in order to determine if the sensor is operating at an optimal level. If the sensor is not operating at an optimal level, the present invention may further involve performing a sensor remedial action. The sensor remedial action involves reversing the DC voltage being applied between the working electrode and the reference electrode. The reversed DC voltage may be coupled with an AC voltage to extend its reach.

Abstract: Methods and devices are provided for the rapid and specific detection of target microorganisms, cells, and the like. In one embodiment, the methods involve contacting a target microorganism (e.g., in a sample) with a permeabilization reagent that selectively permeabilizes or lyses the microorganism; contacting the selectively permeabilized microorganism with a detection reagent that is taken into the selectively permeabilized organism or that contacts metabolites or enzymes released by the selectively permeabilized microorganism, where the detection reagent produces a signal in the presence of said metabolites or enzymes; and detecting a signal produced by the detection reagent in the presence of the metabolites or enzymes wherein the strength of the signal indicates the presence and/or amount of the target microorganism in the sample.

Abstract: A fuel cell which utilizes the biogenic metabolism to produce a high current density is provided. The fuel cell generates electric power in such a way that the fuel is decomposed stepwise by a plurality of enzymes and those electrons formed by oxidation are transferred to the electrode. The enzymes work such that the enzyme activity of the enzyme involved in decomposition in the early stage is smaller than the sum of the enzyme activities of the enzymes involved in decomposition in the later stage. In the case where a coenzyme is involved, the enzyme activity of the oxidase that oxidizes the coenzyme is greater than the sum of the enzyme activities of the enzymes involved in the formation of the reduced form of the coenzyme, out of the enzymes involved in the stepwise decomposition of the fuel.

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 subject invention provides new materials and methods for the efficient isolation and purification of stem cells. Specifically, conductive immunopolymers with stem cell specific antibodies can be used to remove stem cells from biological fluids.

Abstract: A test system comprises a sensor container and a testing device. The sensor container has a base and a lid. The container encloses test sensors therein. The container includes a calibration label attached thereto. The label includes electrical contacts located thereon. The electrical contacts encode calibration information onto the calibration label. The testing device has an auto-calibration feature externally located thereon. The testing device is adapted to determine the analyte concentration in a fluid sample. The auto-calibration feature includes calibration elements that communicate with the electrical contacts on the calibration label. The testing device is adapted to determine the calibration information encoded on the calibration label in response to the calibration elements engaging the electrical contacts. The encoded calibration information is determined without inserting the sensor container or the calibration label into the testing device.

Abstract: An electrode system for measuring the concentration of an analyte under in-vivo conditions comprises a counter-electrode having an electrical conductor, a working electrode having an electrical conductor on which an enzyme layer containing immobilized enzyme molecules for catalytic conversion of the analyte is arranged, and a diffusion barrier that slows the diffusion of the analyte from body fluid surrounding the electrode system to enzyme molecules. The enzyme layer is in the form of multiple fields that are arranged on the conductor of the working electrode at a distance from each other.

Abstract: The concentration of the urea of a urea solution is identified accurately and immediately. A pulse voltage is applied for a predetermined time to a urea concentration identifying sensor heater including a heater and an identifying liquid temperature sensor provided in the vicinity of the heater, a urea solution to be identified is heated by the heater, and the concentration of the urea is identified with a voltage output difference V0 corresponding to a temperature difference between an initial temperature and a peak temperature in the identifying liquid temperature sensor.

Abstract: A ?-conjugated metal complex immobilized substrate, in which ?-conjugated metal complex molecules are connected to a substrate via a ?-conjugated molecular structure, is adapted for observing an electron transfer (redox reaction) of the ?-conjugated metal complex molecules in aqueous electrolytes. An electrochemical device including this ?-conjugated metal complex immobilized substrate and an aqueous electrolyte with cations having an ion radius of r (m) that is not less than a radius of a sphere inscribed in a clearance formed between the ?-conjugated metal complex molecules. The device utilizes an electron transfer (redox reaction) of the ?-conjugated metal complex molecules in the aqueous electrolyte.

Abstract: Disclosed is a mobile communication terminal equipped with temperature compensation function for use in bio-information measurement, including a biosensor insertion in which a biosensor directly detecting bio-information of a subject is inserted, a temperature measurement unit measuring temperatures, and a controller analyzing the bio-information inputted from the biosensor based on stored analysis data and correcting the bio-information using the temperature measured by the temperature measurement unit, in which the temperature measurement unit measures temperature of a target object without contacting the target object directly.

Abstract: The present invention relates to electrochemical sensors for determining gaseous analytes in an aqueous measuring medium, to a process for producing such sensors, and to a process for determining gaseous analytes dissolved in an aqueous measuring medium using the electrochemical sensors. The electrolyte layer of the sensors comprises at least one particulate material and at least one binder which together form a porous, non-swellable framework structure, wherein the pores in this framework structure are configured to absorb a liquid electrolyte or contain the liquid electrolyte.

Abstract: The present invention deals with a device for quick estimation of biochemical oxygen demand of beverage waste water. This device consists of an immobilized microbial membrane attached to an electrode, multimeter and a laptop workstation installed with a developed software. BOD measurement of beverage waste water using this device is rapid, reproducible and effective as compared to conventional titration based methods. This device also excludes COD estimation as required for BOD estimation of waste water. This bio-electrochemical device may find wide commercial application in beverage industries emanating waste waters.

Abstract: Novel membranes comprising various polymers containing heterocyclic nitrogen groups are described. These membranes are usefully employed in electrochemical sensors, such as amperometric biosensors. More particularly, these membranes effectively regulate a flux of analyte to a measurement electrode in an electrochemical sensor, thereby improving the functioning of the electrochemical sensor over a significant range of analyte concentrations. Electrochemical sensors equipped with such membranes are also described.

Abstract: Disclosed is an electrochemical biosensor having a sample introduction channel in which an insulator is employed to introduce a small amount of a sample uniformly and accurately and to adjust an area of a working electrode, thereby guaranteeing the accurate quantitative analysis of a sample. Provided with a sample collection barrier at a sample entrance, the biosensor allows a sample to be introduced at higher accuracy and to be analyzed with higher reproducibility and reliability.

Abstract: Nucleic acids encoding Thermotoga maritima mannitol dehydrogenase and the Thermotoga maritima mannitol dehydrogenase polypeptide are disclosed. Further provided are an electrochemical bioreactor system and a bioreactor electrode that can be used to convert glucose or fructose to mannitol.

Abstract: The present invention relates to diagnostic devices incorporating electrode modules and fluidics for performing chemical analyses. The invented devices consist of a sensor array formed on an electrode module, the sensor array being contained within a fluidic housing. The electrode module is a laminate of a perforated epoxy foil and a photo-formed metal foil with sensor membranes deposited into the perforations. The fluidic housing is an element consisting of a plastic card-like body with fluidic conduits and a sealed fluid reservoir contained in a foil-lined cavity.

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: A sensor including a sensing layer is disposed over an electrode or an optode and a layer-by-layer assembled mass transport limiting membrane disposed over the sensing layer. The membrane includes at least one layer of a polyanionic or polycationic material. The assembled layers of the membrane are typically disposed in an alternating manner. The sensor also optionally includes a biocompatible membrane.

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: 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 provides a polymer membrane enhanced with cured epoxy resin for use as the outer membrane of biosensors. The membrane includes approximately 30-80% epoxy resin adhesives, 10-60% polymer such as poly(vinyl chloride), polycarbonate and polyurethane and 0-30% plasticizers and 5-15% surface modifier reagent such as polyethylene oxide-containing block copolymers. Utilizing the polymer membrane of the present invention, a three-layered sensing element has been developed. This sensing element will be particularly useful for miniaturized biosensors used for in vitro blood measurements or for continuous in vivo monitoring such as implantable biosensors. This element includes an enzyme layer, an interference-eliminating layer and the novel polymer member of the present invention as the outer polymer layer. This novel sensing element shows excellent response characteristics in solutions and has an extremely long lifetime.

Abstract: A system for the measurement of analyte concentration includes an electrochemical cell having a working electrode coated with a protein layer and a diffusion limiting barrier covering the protein layer, and a counter electrode; a voltage source which provides a voltage between the working electrode and the counter electrode when electrically connected by a conductive medium; and a computing system which measures the dynamic voltage output to the counter electrode within a time period prior to a response from the working electrode and method for use is disclosed.

Abstract: The present invention relates to a mutant protein of PQQ-dependent s-GDH characterized in that in at least one of the positions 122 and 124 the amino acid lysine is present, wherein these positions correspond to the amino acid positions known from the A. calcoaceticus s-GDH wild-type sequence (SEQ ID NO: 2), it also discloses genes encoding such mutant s-GDH, and different applications of these s-GDH mutants, particularly for determining the concentration of glucose in a sample.

Abstract: A mutant glucose dehydrogenase having the amino acid sequence of SEQ ID NO: 3 or an amino acid sequence of SEQ ID NO: 3 including substitution, deletion, insertion or addition of one or more amino acid residues other than the amino acid residue at the 365th position and having glucose dehydrogenase activity, wherein an amino acid residue at a position corresponding to the 365th position of the amino acid sequence is replaced with another amino acid residue, and the mutant glucose dehydrogenase shows an improved substrate specificity to glucose.

Abstract: Disclosed herein are systems and methods for a continuous analyte sensor, such as a continuous glucose sensor. One such system utilizes first and second working electrodes to measure analyte or non-analyte related signal, both of which electrode include an interference domain.

Abstract: An electrochemical biosensor test strip with four new features. The test strip includes an indentation for tactile feel as to the location of the strips sample application port. The sample application port leads to a capillary test chamber, which includes a test reagent. The wet reagent includes from about 0.2% by weight to about 2% by weight polyethylene oxide from about 100 kilodaltons to about 900 kilodaltons mean molecular weight, which makes the dried reagent more hydrophilic and sturdier to strip processing steps, such as mechanical punching, and to mechanical manipulation by the test strip user. The roof of the capillary test chamber includes a transparent or translucent window which operates as a “fill to here” line, thereby identifying when enough test sample (a liquid sample, such as blood) has been added to the test chamber to accurately perform a test. The test strip may further include a notch located at the sample application port. The notch reduces a phenomenon called “dose hesitation”.