Abstract: Methods and systems are provided for concentrating particles (e.g., bacteria, viruses, cells, and nucleic acids) suspended in a liquid. Electric-field-induced forces urge the particles towards a first electrode immersed in the liquid. When the particles are in close proximity to (e.g., in contact with) the first electrode, the electrode is withdrawn from the liquid and capillary forces formed between the withdrawing electrode and the surface of the liquid immobilize the particles on the electrode. Upon withdrawal of the electrode from the liquid, the portion of the electrode previously immersed in the liquid has particles immobilized on its surface.

Abstract: A subtractive corrective assay device and methodology, whereby ail required binding and label detection reagents are initially located within the detection zone. Application of a magnetic field is used to selectively remove bound label from the detection zone by means of paramagnetic particles. The relationship between measured label concentration before and after the application of a magnetic field within the detection zone is used to accurately measure analyte concentration within the sample.

Abstract: The present invention is directed to systems, devices and methods for identifying biopolymers, such as strands of DNA, as they pass through a constriction such as a carbon nanotube nanopore. More particularly, the invention is directed to such systems, devices and methods in which a newly translocated portion of the biopolymer forms a temporary electrical circuit between the nanotube nanopore and a second electrode, which may also be a nanotube. Further, the invention is directed to such systems, devices and methods in which the constriction is provided with a functionalized unit which, together with a newly translocated portion of the biopolymer, forms a temporary electrical circuit that can be used to characterize that portion of the biopolymer.

Abstract: Methods of modulating the binding interactions between a (biomolecular) probe or detection agent and an analyte of interest from a biological sample in a biosensor having a multisite array of test sites. In particular, the methods modulate the pH or ionic concentration gradient near the electrodes in such biosensor. The methods of modulating the binding interactions provide a biosensor and analytic methods for more accurately measuring an analyte of interest in a biological sample.

Abstract: Analytes in a liquid sample are determined by methods utilizing sample volumes of less than about 1.0 ?l and test times within about eight seconds. The methods are preferably performed using small test strips including a sample receiving chamber filled with the sample by capillary action.

Abstract: A method and apparatus for testing workpiece overcoats is described.

Abstract: The present invention provides compositions, devices and methods for detecting esterase activity. The present invention also provides devices and methods of detecting esterase inhibitors, for example, organophosphates. In particular, the present invention provides a biosensor comprising Neuropathy Target Esterase (NTE) polypeptides. Further, the present invention relates to medicine, industrial chemistry, agriculture, and homeland security.

Abstract: Methods for determining a concentration of an analyte in a sample, and the devices and systems used in conjunction with the same, are provided herein. In one exemplary embodiment of a method for determining a concentration of an analyte in a sample, the method includes detecting a presence of a sample in an electrochemical sensor including two electrodes. A fill time of the sample is determined with the two electrodes and a correction factor is calculated in view of at least the fill time. The method also includes reacting an analyte that causes a physical transformation of the analyte between the two electrodes. A concentration of the analyte can then be determined in view of the correction factor with the same two electrodes. Systems and devices that take advantage of the fill time to make analyte concentration determinations are also provided.

Abstract: Various embodiments provide devices, methods, and systems for high throughput biomolecule detection using transducer arrays. In one embodiment, a transducer array made up of transducer elements may be used to detect byproducts from chemical reactions that involve redox genic tags. Each transducer element may include at least a reaction chamber and a fingerprinting region, configured to flow a fluid from the reaction chamber through the fingerprinting region. The reaction chamber can include a molecule attachment region and the fingerprinting region can include at least one set of electrodes separated by a nanogap for conducting redox cycling reactions. In embodiments, by flowing the chamber content obtained from a reaction of a latent redox tagged probe molecule, a catalyst, and a target molecule in the reaction chamber through the fingerprinting region, the redox cycling reactions can be detected to identify redox-tagged biomolecules.

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

Abstract: The present invention relates to an analytical tool (X) which includes a substrate (1), a flow path for moving a sample along the substrate (1), a reagent portion (14) provided in the flow path, and an insulating film (13) covering the substrate (1) and including an opening (15a) for defining a region for forming the reagent portion (14). The insulating film (13) further includes at least one additional opening (15b) positioned in a longitudinal direction (N1) relative to the opening (15a). For instance, the flow path is configured to move the sample by capillary force.

Abstract: Methods for distinguishing between an aqueous non-blood sample (e.g., a control solution) and a blood sample are provided herein. In one aspect, the method includes using a test strip in which multiple current transients are measured by a meter electrically connected to an electrochemical test strip. The current transients are used to determine if a sample is a blood sample or an aqueous non-blood sample based on characteristics of the sample (e.g., amount of interferent present, reaction kinetics, and/or capacitance). The method can also include calculating a discrimination criteria based upon these characteristics. Various aspects of a system for distinguishing between a blood sample and an aqueous non-blood sample are also provided herein.

Abstract: An electrochemical test sensor for detecting the analyte concentration of a fluid test sample includes a base, a dielectric layer, a reagent layer and a lid. The base provides a flow path for the test sample having on its surface a counter electrode and a working electrode adapted to electrically communicate with a detector of electrical current. The dielectric layer forms a dielectric window therethrough. The reagent layer includes an enzyme that is adapted to react with the analyte. The lid is adapted to mate with the base and to assist in forming a capillary space with an opening for the introduction of the test sample thereto. At least a portion of the width of the counter electrode is greater than the width of the working electrode.

Abstract: A disposable urea sensor has a laminated body having a fluid sample inlet end and an electrical contact end, a fluid sample inlet, a substantially flat sample chamber in communication between the fluid sample inlet and a vent opening, the sample chamber being adapted to collect a fluid sample through the fluid sample inlet, a working electrode and a reference electrode within the sample chamber, and a reagent matrix disposed on the working electrode wherein the reagent matrix contains urease.

Abstract: A test sensor includes a body, a first conductive trace, a second conductive trace, and a third conductive trace. The body includes a first region that has a fluid-receiving area, a second region separate from the first region, and a first temperature sensing interface disposed at or adjacent to the fluid-receiving area. The fluid-receiving area receives a sample. The first trace is disposed on the body, and at least a portion of the first trace is disposed in the first region. The second and third traces are disposed on the body. The third trace extends from the first to the second regions. The third trace is connected to the first trace at the first temperature sensing interface. The third trace includes a different material than the first trace. A first thermocouple is formed at the first temperature sensing interface. The thermocouple provides temperature data to determine an analyte concentration.

Abstract: An electrochemical test device is provided having a base layer with a first electrode thereon and a top layer with a second electrode thereon. The two electrodes are separated by a spacer layer having an opening therein, such that a sample-receiving space is defined with one electrode on the top surface, the other electrodes on the bottom surface and side walls formed from edges of the opening in the spacer. Reagents for performing the electrochemical reaction are deposited on one of the electrodes and on the side walls of the sample-receiving space.

Abstract: A sensor array with at least three electrodes and a switching unit is disclosed, as well as a process for operating such a sensor array for implementing an electrochemical analysis process. The at least three electrodes can be selectively switched as counter-electrodes or as a working electrode which can be electrically coupled to an electrolytic analyte. The at least three electrodes are set up in such a way that sensor events occur at an electrode switched as working electrode in the electrolyte solution, in the presence of the electrolytic analyte. The electrodes which are not required as working electrodes at a particular point in time for detecting the electrolytic analyte can thus be switched together to form the counter-electrode of the sensor array, thus dispensing with the need for a separate counter-electrode.

Abstract: A method and device for performing DNA sequencing and extracting structural information from unknown nucleic acid strands. The device includes a microwell structure, where identical DNA strands are immobilized within the microwell structure on a surface of a micro-bead, an active electrode or a porous polymer. The device further includes a CMOS-integrated semiconductor integrated circuit, where the CMOS-integrated semiconductor integrated circuit includes metal layers on a silicon substrate, where the metal layers form an active electrode biosensor. In addition, a sensing electrode is formed by creating openings in a passivation layer of the CMOS-integrated semiconductor integrated circuit to hold a single bead, on which the DNA strands are immobilized.

Abstract: A system for electrochemical quantitative analysis is provided. The system includes a measuring apparatus having a plurality of analysis modes. Each of the analysis modes is for quantitatively analyzing different biochemical substance. The system further includes a plurality of test strips. Each of the test strips has a different identification component for a different analysis mode. When one of the plurality of test strips is selected to electronically connect to the measuring apparatus, the measuring apparatus executes one of the plurality of analysis modes according to the identification component of the selected test strip to quantitatively analyze a corresponding biochemical substance.

Abstract: The present invention provides a system of biosensors whose dose-response curves are maintained within a predetermined and desired range or tolerance during production by selecting a feature of the biosensors that can be varied during production. For example, in one exemplary embodiment the effective area of the working electrode of an electrochemical biosensor can be varied during production as needed to offset variations that occur, e.g., in the reagent of the biosensors as production proceeds. In another exemplary embodiment, the dose-response curve of biosensors not yet produced can be predicted and one or more features of these biosensors can be selected to maintain the dose-response curve within a predetermined range or tolerance.

Abstract: A disposable biosensor for determining the content of hemoglobin and hematocrit in a sample of whole blood that includes a laminated strip with a first and second end, at least a reference, a working electrode and a blank electrode embedded in the laminated strip. The working electrode contains a reagent sensitive to hemoglobin or hemotocrit. The blank electrode is used to measure oxidizable species in the fluid sample and to correct the current signal of the working electrode. The construction of the biosensor allows accurate measurement of the impedance of a small fluid sample, which is used to further correct the current signal of the working electrode.

Abstract: Methods of determining a corrected analyte concentration in view of some error source are provided herein. The methods can be utilized for the determination of various analytes and/or various sources of error. In one example, the method can be configured to determine a corrected glucose concentration in view of an extreme level of hematocrit found within the sample. In other embodiments, methods are provided for identifying various system errors and/or defects. For example, such errors can include partial-fill or double-fill situations, high track resistance, and/or sample leakage. Systems are also provided for determining a corrected analyte concentration and/or detecting some system error.

Abstract: The purpose of the invention is to provide a method for accurately quantifying a chemical substance by a substitutional stripping voltammetry technique. A method is provided for quantifying a chemical substance contained in a sample solution, and the method comprises preparing a measurement system. The measurement system comprises a pair of working electrodes (a first and a second electrodes), a counter electrode, and a gel-coated electrode. This gel-coated electrode comprises an electrode surface, a stripping gel, and a protection gel, and the protection gel covers the stripping gel.

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: Sensor devices, methods and kits for detection of biomolecules are provided. According to various embodiments, the devices, methods and kits provide enhanced sensitivity through the measurement of electrochemical impedance and related properties. Certain embodiments employ nanostructured electrode elements including nanotubes, nanoparticles, nanowires, and nanocones. In a particular embodiment, single walled carbon nanotubes disposed in interconnected networks are used as electrodes. The device, methods and kits described herein have application for detection and measurement of biomolecular species including polynucleotides, proteins, polysaccharides and the like.

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: An electrode for electrochemical analysis is described, the electrode comprising: an insulating surface; a three-dimensional network of carbon nanotubes situated on the insulating surface; and an electrically conducting material in electrical contact with the carbon nanotubes; wherein the carbon nanotubes are oriented substantially parallel to the insulating surface. Also described is a method of manufacturing the electrode, and a method of electrochemically analysing a solution using electrodes of this type, and an associated assay device or kit.

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

Abstract: A protein comprising an amino acid sequence having at least one mutation selected from a Gly-4 to Ala mutation, a Glu-6 to His mutation, a Ser-14 to Thr mutation, an Ala-37 to Thr or Arg mutation, a Pro-50 to Gln mutation, a Glu-67 to Gly mutation, an Asp-80 to Tyr mutation, a Val-93 to Met mutation, an Arg-156 to Pro mutation, a Leu-164 to Met mutation, an Asn-202 to Asp mutation, a Thr-235 to Ala mutation, an Asn-348 to Tyr mutation, a Gly-362 to Arg mutation and a Val-473 to Ala mutation in the amino acid sequence depicted in SEQ II NO:4. (2) A thermostable protein which comprises an amino acid sequence derived from the amino acid sequence having at least one variation described in (1) and having 1,5-anhydroglucitol dehydrogenase activity. These proteins act specifically on 1,5-anhydroglucitol (1,5-AG), have thermal stability and exhibit excellent storage stability.

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: 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 concentration of glucose in a blood sample is determined by methods utilizing test strips having a sample receiving cavity having a volume of less than 1 ?l and determining the glucose concentration within a time period of less than 10 seconds.

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 method is disclosed for determining analyte concentration that includes applying a first electrical potential excitation pulse to a body fluid sample in an analyte sensor, and a first current response of the body fluid sample to the first pulse is measured. A second excitation pulse is applied to the body fluid sample in the analyte sensor, and a second current response of the body fluid sample to the second pulse is measured. An analyte level in the body fluid sample is determined by compensating for sources of error based on the first current response to the first pulse.

Abstract: A diabetes management system and method are provided herein that may be used to analyze a patient's level of control of their diabetes, by looking at the difference between blood glucose measurements taken before and after a meal. If the standard deviation of the differences D calculated between pre- and post-prandial results is found to vary significantly from a predetermined threshold value, then a message or graphical indication may be displayed to the user. Messages may provide suggestions to the user as to ways to better manage their condition to ensure compliance of any prescribed diabetes regimen or to guide the patient in managing their diabetes.

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

Abstract: The disclosure also relates to novel methods for detection of biological targets using amplification steps in conjunction with conversion of functional groups attached to a transitional metal complex, resulting in quantifiable electrochemical signal at two unique potentials, E°1 and E°2.

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: An electrochemical biosensor with electrode elements that possess smooth, high-quality edges. These smooth edges define gaps between electrodes, electrode traces and contact pads. Due to the remarkable edge smoothness achieved with the present invention, the gaps can be quite small, which provides marked advantages in terms of test accuracy, speed and the number of different functionalities that can be packed into a single biosensor. Further, the present invention provides a novel biosensor production method in which entire electrode patterns for the inventive biosensors can be formed all at one, in nanoseconds—without regard to the complexity of the electrode patterns or the amount of conductive material that must be ablated to form them.

Abstract: Described and illustrated herein are systems and exemplary methods of operating a multianalyte measurement system having a meter and a test strip. In one embodiment, the method may be achieved by applying a test voltage between a reference electrode and a first working electrode; measuring a first test current, a second test current and a third test current at the working electrode with the meter after a blood sample containing an analyte is applied to the test strip; estimating a hematocrit-corrected analyte concentration from the first, second and third test currents; and displaying the hematocrit-corrected analyte concentration.

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: The present invention provides a method of measuring a component in blood, by which an amount of the component can be corrected accurately by measuring a hematocrit (Hct) value of the blood with high accuracy and high reliability and also provides a sensor used in the method. The sensor for measuring a component in blood has a first analysis portion and a second analysis portion. The first analysis portion has a first electrode system (11,12) and a reagent layer (14), and the reagent layer (14) has an oxidoreductase that acts on the component and a mediator. In the first analysis portion, the component in the blood is measured by causing a redox reaction of the component with the oxidoreductase in the presence of the mediator and detecting a redox current caused when a voltage is applied by the first electrode (11,12). The second analysis portion has a working electrode and a counter electrode, and a mediator is provided on the counter electrode but not on the working electrode.

Abstract: The method includes: providing a test strip comprising a reference electrode and a working electrode coated with a reagent layer; applying a fluid sample to the test strip for a reaction period; applying a test voltage between the reference electrode and the working electrode; measuring a test current as a function of time; measuring a steady state current value when the test current has reached an equilibrium; calculating a ratio of the test current to the steady state current value; plotting the ratio of the test current to the steady state current value as a function of the inverse square root of time; calculating an effective diffusion coefficient from the slope of the linearly regressed plot of the ratio of the test current to the steady state current value as a function of the inverse square root of time; and calculating a hematocrit-corrected concentration of analyte.

Abstract: Described herein is a method of detecting an analyte comprising providing a capture electrode comprising probe molecules at the surface thereof, wherein the probe molecules are designed to specifically bind to said analyte, contacting the capture electrode with a sample solution, such that said analyte in the solution forms a probe-analyte complex at the surface of said capture electrode, and measuring the electrical properties of the capture electrode after contact with said sample solution, wherein changes in said electrical properties are indicative of the formation of the probe-analyte complex at the electrode surface. The measuring is conducted in measuring solutions comprising solvents having high dielectric constants, or measuring solutions having high pH, or with electrode surfaces having been contacted with solutions comprising organic solvents.

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: The present invention provides a method of measuring a component in blood, by which an amount of the component can be corrected accurately by measuring a hematocrit (Hct) value of the blood with high accuracy and high reliability and also provides a sensor used in the method. The sensor for measuring a component in blood has a first analysis portion and a second analysis portion. The first analysis portion has a first electrode system (11,12) and a reagent layer (14), and the reagent layer (14) has an oxidoreductase that acts on the component and a mediator. In the first analysis portion, the component in the blood is measured by causing a redox reaction of the component with the oxidoreductase in the presence of the mediator and detecting a redox current caused when a voltage is applied by the first electrode (11,12). The second analysis portion has a working electrode and a counter electrode, and a mediator is provided on the counter electrode but not on the working electrode.

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: An electrochemical test sensor adapted to assist in determining the concentration of analyte in a fluid sample is disclosed. The sensor comprises a base that assists in forming an opening for introducing the fluid sample, a working electrode being coupled to the base, and a counter electrode being coupled to the base, the counter electrode and the working electrode being adapted to be in electrical communication with a detector of electrical current, and a sub-element being coupled to the base. A major portion of the counter electrode is located downstream relative to the opening and at least a portion of the working electrode. The sub-element is located upstream relative to the working electrode such that when electrical communication occurs between only the sub-element and the working electrode there is insufficient flow of electrical current through the detector to determine the concentration of the analyte in the fluid sample.

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.