Abstract: An improved electrochemical sensor having a base bearing a working and counter electrode which provides a flow path for a fluid test sample. The working and counter electrodes are configured so that a major portion of the counter electrode is located downstream on the flow path from the working electrode with the exception of a small sub-element of the counter electrode which is in electrical communication with the primary portion of the counter electrode and located upstream of the working electrode. This configuration enables the sensor when the capillary space is incompletely filled with test fluid.

Abstract: An electrochemical sensor is provided comprised of a thin sheet or film having at least one through-hole provided therein. The thin sheet or film has first and second opposing surfaces, at least a portion of the opposing surfaces being coated with a conductive coating which extends into the at least one through-hole, each conductive coating extending partially into the at least one through-hole from each opposing surface whereby each conductive coating terminates within the at least one through-hole at a point spaced from the terminus of the opposing conductive coating which extends into the at least one through-hole, whereby the conductive coatings in the at least one through-hole are separated by a non-conductive interior surface of the at least one through-hole.

Abstract: Disclosed is an improved electrochemical sensor having a base bearing a working and counter electrode which provides a flow path for a fluid test sample. The working electrode has a reaction layer on its surface which contains an enzyme capable of reacting with an analyte to produce electrons which are received by the working electrode. The base is mated with a cover to form a capillary space into which the test fluid is drawn. The improvement involves configuring the working and counter electrodes so that a major portion of the counter electrode is located downstream on the flow path from the working electrode with the exception of a small sub-element of the counter electrode which is in electrical communication with the primary portion of the counter electrode and located upstream of the working electrode.

Abstract: Disclosed is an improved electrochemical sensor having a base bearing a working and counter electrode which provides a flow path for a fluid test sample. The working electrode has a reaction layer on its surface which contains an enzyme capable of reacting with an analyte to produce electrons which are received by the working electrode. The base is mated with a cover to form a capillary space into which the test fluid is drawn. The improvement involves configuring the working and counter electrodes so that a major portion of the counter electrode is located downstream on the flow path from the working electrode with the exception of a small sub-element of the counter electrode which is in electrical communication with the primary portion of the counter electrode and located upstream of the working electrode.

Abstract: Disclosed is an electrochemical sensor for the determination of analytes in body fluids, e.g. glucose in blood. The sensor involves a non-conductive base which provides a flow path for the body fluid with the base having a working and counter electrode on its surface which are in electrical communication with a detector of current. The base and a cover therefore provide a capillary space containing the electrodes into which the body fluid is drawn by capillary action. The counter electrode has a sub-element which contains an electroactive material and is configured in the system (sensor and meter) to provide an error signal when insufficient body fluid is drawn into the capillary.

Abstract: An electrochemical sensor is provided comprised of a thin sheet or film having at least one through-hole provided therein. The thin sheet or film has first and second opposing surfaces, at least a portion of the opposing surfaces being coated with a conductive coating which extends into the at least one through-hole, each conductive coating extending partially into the at least one through-hole from each opposing surface whereby each conductive coating terminates within the at least one through-hole at a point spaced from the terminus of the opposing conductive coating which extends into the at least one through-hole, whereby the conductive coatings in the at least one through-hole are separated by a nonconductive interior surface of the at least one through-hole.

Abstract: Disclosed is an electrochemical sensor for detecting the concentration of an analyte such as glucose in a fluid test sample. The sensor involves a base as flow path for the fluid test sample having a working and counter electrode on its surface. The base is mated with a cover to form a capillary space to capture the fluid and the counter electrode has a sub-element located upstream in the flow path. When there is detected electrical communication only between the sub-element and the working electrode the meter, with which the sensor is in electrical communication senses that the capillary space has not completely filled with test fluid.

Abstract: Disclosed is an improved electrochemical sensor having a base bearing a working and counter electrode which provides a flow path for a fluid test sample. The working electrode has a reaction layer on its surface which contains an enzyme capable of reacting with an analyte to produce electrons which are received by the working electrode. The base is mated with a cover to form a capillary space into which the test fluid is drawn. The improvement involves configuring the working and counter electrodes so that a major portion of the counter electrode is located downstream on the flow path from the working electrode with the exception of a small sub-element of the counter electrode which is in electrical communication with the primary portion of the counter electrode and located upstream of the working electrode.

Abstract: A method and apparatus are provided for calibrating a sensor for determination of analyte concentration. The meter includes a sensor for receiving a user sample to be measured and a processor for performing a predefined test sequence for measuring a predefined parameter value. A memory can be coupled to the processor for storing predefined parameter data values. A calibration code is associated with the sensor and read by the processor before the user sample to be measured is received. The calibration code is used in measuring the predefined parameter data value to compensate for different sensor characteristics.

Abstract: The present invention concerns an electrochemical sensor made up of an insulating base having an electrode layer on its surface and a lid of deformable material which comprises a concave area in the central portion thereof, so that when it is mated with the base, the lid and base form a capillary space containing the electrode layer. When the electrode layer is in operative contact with a reaction layer comprising an enzyme which will cause the production of mobile electrons when contacted with a suitable analyte, the concentration of analyte, e.g. glucose in blood, can be measured by measuring the current created by the flow of mobile electrons when contacted with a suitable analyte, the concentration of analyte, e.g. glucose in blood, can be measured by measuring the current created by the flow of mobile electrons.

Abstract: A sensor for use in a sensor dispensing instrument so that fluids can be tested when the sensor is ejected from within a sensor cavity of a sensor pack sealed by a foil. The sensor has a generally flat, rectangular shape, is formed by a base and a lid, and has perpendicularly extending longitudinal and transverse axes. A notch in a rear end of the sensor is engaged by a knife blade within the sensor dispensing instrument as the sensor is being ejected through the foil. A front testing edge of the lid overhangs a front testing edge of the base of the sensor. One side edge of the sensor adjacent the front edges of the base and lid is beveled at about a 25.degree. angle. The front base edge extends from the beveled side portion across the entire remaining width of the sensor at an angle of approximately 10.degree. with respect to the transverse axis. A portion of the front lid edge extends from the beveled side portion across a significant portion of the width of the sensor at an angle of about 15.degree.

Abstract: Apparatus and method are provided for determining the concentration of an analyte in a fluid test sample by applying the fluid test sample to the surface of a working electrode which is electrochemically connected to a reference electrode which surface bears a composition comprising an enzyme specific for the analyte. A mediator is reduced in response to a reaction between the analyte and the enzyme. An oxidizing potential is applied between the electrodes to return at least a portion of the mediator back to its oxidized form before determining the concentration of the analyte to thereby increase the accuracy of the analyte determination. Following this initially applied potential, the circuit is switched to an open circuit or to a potential that substantially reduces the current to minimize the rate of electrochemical potential at the working electrode. A second potential is applied between the electrodes and the current generated in the fluid test sample is measured to determine analyte concentration.

Abstract: Apparatus and method are provided for determining the concentration of an analyte in a fluid test sample by applying the fluid test sample to the surface of a working electrode which is electrochemically connected to a reference electrode which surface bears a composition comprising an enzyme specific for the analyte. A mediator is reduced in response to a reaction between the analyte and the enzyme. An oxidizing potential is applied between the electrodes to return at least a portion of the mediator back to its oxidized form before determining the concentration of the analyte to thereby increase the accuracy of the analyte determination. Following this initially applied potential, the circuit is switched to an open circuit or to a potential that substantially reduces the current to minimize the rate of electrochemical potential at the working electrode. A second potential is applied between the electrodes and the current generated in the fluid test sample is measured to determine analyte concentration.

Abstract: Disclosed is an improved electrode suitable for the electrochemical regeneration of the co-enzymes NADH and NADPH. The electrode has imparted on its surface a mediator function which is a 3-phenylimino-3H-phenothiazine or a 3-phenylimino-3H-phenoxazine. Also disclosed is a method of improving the performance of a biochemical fuel cell which operates with a dehydrogenase as a catalyst and a co-enzyme as the energy-transferring redox couple which involves using the improved electrode in the fuel cell.

Abstract: Disclosed is an electrode suitable for the electrochemical regeneration of the co-enzymes NADH and NADPH. The electrode has imparted on its surface a mediator function which is a 3-methylene-3H-phenothiazine or a 3-methylene-3H-phenoxazine compound.

Abstract: A method of making and an amperometric electrode are provided. An electrode carbon ink is applied to a polymer substrate to form a working electrode. The substrate carrying the working electrode is placed in a gas plasma cleaner, such as an oxygen or nitrogen plasma, to clean the working electrode. A high radio frequency signal excites the gas plasma for a short exposure time in a range between 10 seconds and 30 seconds. Then a reagent layer is deposited to the plasma treated working electrode.

Abstract: Disclosed is the use of 9H-acridin-2-one and 11H-dibenz-[b,f][1,4]oxazepin-8-one compounds as mediators suitable for the electrochemical regeneration of the co-enzymes dihydronicotinamide adenine dinucleotide (NADH), dihydronicotinamide adenine dinucleotide phosphate (NADPH) or analogs thereof.

Abstract: A conductive sensor and its use in a diagnostic assay are disclosed. The miniaturized conductive sensor, utilizing a conducting polymer, is used in a diagnostic device to determine the presence or concentration of a predetermined analyte in a liquid test sample, wherein the predetermined analyte, like glucose, is assayed by an oxidase interaction. The interaction between the oxidase and a small amount of the predetermined analyte in the test sample generates, either directly or indirectly, a dopant compound in a reaction zone of the conductive sensor. The dopant compound then migrates to the detection zone of the conductive sensor of the diagnostic device to oxidize the conducting polymer and convert the conducting polymer from an insulating form to a conducting form. The resulting increase in conductivity of the conducting polymer is measured, then the conductivity increase is correlated to the concentration of the predetermined analyte in the test sample.

Abstract: A conductive sensor and its use in a diagnostic assay are disclosed. The miniaturized conductive sensor, utilizing a conducting polymer, is used in a diagnostic device to determine the presence or concentration of a predetermined analyte in a liquid test sample, wherein the predetermined analyte, like glucose, is assayed by an oxidase interaction. The interaction between the oxidase and a small amount of the predetermined analyte in the test sample generates, either directly or indirectly, a dopant compound in a reaction zone of the conductive sensor. The dopant compound then migrates to the detection zone of the conductive sensor of the diagnostic device to oxidize the conducting polymer and convert the conducting polymer from an insulating form to a conducting form. The resulting increase in conductivity of the conducting polymer is measured, then the conductivity increase is correlated to the concentration of the predetermined analyte in the test sample.