Abstract: An oxygen sensor has a laminated body with a fluid sample inlet end and an electrical contact end, a fluid sample inlet, a substantially flat test chamber communicating with the fluid sample inlet where the test chamber is adapted to collect a fluid sample through the sample fluid inlet, a working electrode and a reference electrode within the test chamber, and a reagent matrix disposed on the working electrode where the reagent matrix contains an oxidase, a reduced form of a redox mediator and a peroxidase.

Abstract: Methods for operating a sensor device are provided, which may include (a) providing at a site (e.g., implanting in a patient) a device which comprises at least first and second reservoirs, a first sensor and corresponding first reference sensor located within the first reservoir, a second sensor and corresponding second reference sensor located within the second reservoir, a first reservoir cap closing an opening in the first reservoir and a second reservoir cap closing an opening in the second reservoir, and a power source, control circuitry, and electrodes for selectively disintegrating each reservoir cap; (b) disintegrating the first reservoir cap and operating the first sensor and reference sensor; and (c) using the first reference sensor to determine whether the first sensor is operating properly. If not operating properly, then the control circuitry initiates disintegration of the second reservoir cap and operation of the second sensor and reference sensor.

Abstract: Methods are provided for making a reservoir-based sensor device. The method may include fabricating a first substrate portion which comprises an upper surface, an opposed lower surface, a plurality of through holes defining reservoirs between said upper surface and said lower surface, and a plurality of reservoir caps closing off one end of said through holes at said upper surface; fabricating a plurality of sensors on an upper surface of a second substrate portion; aligning the first and second substrate portions such that each of said plurality of sensors is in alignment with each of said plurality of reservoirs; and bonding together the lower surface of said first substrate portion and the upper surface of said second substrate portion to seal each of said sensors inside the reservoir with which it is aligned.

Abstract: A system and method for correcting the oxygen effect on oxidase-based analyte sensors includes an oxygen sensor with a working electrode, a reagent matrix disposed on at least the working electrode that contains a reduced form of a redox mediator, an oxidase and a peroxidase, an oxidase-based analyte sensor, a means for determining the oxygen concentration in a portion of a fluid sample using the oxygen sensor, means for determining an analyte concentration in another portion of the fluid sample using the oxidase-based analyte sensor, and means for using the oxygen concentration in the fluid sample to determine a corrected analyte concentration in the fluid sample.

Abstract: A method of compensating for the presence of hematocrit in a blood sample when measuring a blood analyte using a disposable sensor strip. The method includes disposing a blood sample onto a working electrode and a reference electrode of the disposable sensor strip to obtain a concentration of an analyte in the blood sample, measuring a resistance value of the blood sample between the reference electrode and the working electrode, and calculating a corrected concentration of the analyte using the resistance value and a hematocrit equation to correct for the presence of hematocrit in the blood sample.

Abstract: An improved biosensor having at least a first working electrode and a first electrode material disposed on the first working electrode. The first electrode material is a mixture made by combining at least one enzyme where the at least one enzyme is a capable of reacting with the analyte to be measured, a redox mediator capable of reacting with a product of an enzymatic reaction or a series of enzymatic reactions involving the at least one enzyme, a peroxidase capable of catalyzing a reaction involving the redox mediator where the redox mediator is oxidized, a binder and a surfactant.

Abstract: Devices are provided for the controlled exposure of a sensor or sensor component. The device may include a substrate; at least one reservoir provided in the substrate; at least one sensor or sensor component located in the at least one reservoir; at least one reservoir cap closing an opening in the at least one reservoir to isolate the sensor or sensor component from a selected environmental component outside of the at least one reservoir; at least one intermediate barrier layer disposed in the at least one reservoir between the reservoir cap and the sensor or sensor component; and means for disintegrating the reservoir cap to expose the sensor or sensor component to the selected environmental component.

Abstract: A bilirubin sensor has a working electrode with a first chemical matrix disposed thereon that contains a binder, a substrate electrode with a second chemical matrix dispose thereon that contains a binder and a chemical agent that consumes bilirubin, a reference electrode, a sample chamber containing the working electrode, the substrate electrode and the reference electrode, and a method of measuring bilirubin in a body fluid.

Abstract: Methods for operating a sensor device are provided, which may include (a) providing at a site (e.g., implanting in a patient) a device which comprises at least first and second reservoirs, a first sensor and corresponding first reference sensor located within the first reservoir, a second sensor and corresponding second reference sensor located within the second reservoir, a first reservoir cap closing an opening in the first reservoir and a second reservoir cap closing an opening in the second reservoir, and a power source, control circuitry, and electrodes for selectively disintegrating each reservoir cap; (b) disintegrating the first reservoir cap and operating the first sensor and reference sensor; and (c) using the first reference sensor to determine whether the first sensor is operating properly. If not operating properly, then the control circuitry initiates disintegration of the second reservoir cap and operation of the second sensor and reference sensor.

Abstract: Methods are provided for making a reservoir-based sensor device. The method may include fabricating a first substrate portion which comprises an upper surface, an opposed lower surface, a plurality of through holes defining reservoirs between said upper surface and said lower surface, and a plurality of reservoir caps closing off one end of said through holes at said upper surface; fabricating a plurality of sensors on an upper surface of a second substrate portion; aligning the first and second substrate portions such that each of said plurality of sensors is in alignment with each of said plurality of reservoirs; and bonding together the lower surface of said first substrate portion and the upper surface of said second substrate portion to seal each of said sensors inside the reservoir with which it is aligned.

Abstract: A sensor strip with capillary flow control has a base layer having a plurality of conductive paths delineated thereon, an electrode forming layer disposed on the base layer, the electrode forming layer having a first opening forming a working electrode, a second opening forming a reference electrode, and a flow-control mechanism, a spacer layer disposed on the electrode forming layer, and a cover layer with a vent opening disposed on the spacer layer and forming a substantially flat sample channel with walls formed by the electrode forming layer, the spacer layer and the cover layer, the substantially flat sample chamber having a sample inlet adjacent a proximal end and the vent opening adjacent a distal end where the substantially flat sample chamber contains the working electrode, the reference electrode and the flow-control mechanism.

Abstract: A disposable electrode strip for testing a fluid sample including a laminated strip with a first and second end, a vent, an open path for receiving a fluid sample of less than one microliter beginning from the first end and connecting to the vent, a working electrode, a reference electrode and a pseudo-working electrode embedded in the laminated strip within the open path and proximate to the first end, a reagent matrix coextensive within the open path and covering the three electrodes, and conductive contacts located at the second end of the laminated strip.

Abstract: Microchip devices and methods of use are provided for the controlled exposure of a secondary device. In one embodiment, the microchip device include a substrate, a plurality of reservoirs in the substrate, a secondary device in one or more of the reservoirs, at least one barrier layer covering each of the reservoirs to isolate the secondary device from an environmental component outside the reservoirs, wherein the barrier layer is impermeable to the environmental component, and a microprocessor-controlled actuation means for rendering the barrier layer porous or permeable to the environmental component to expose the secondary device to said environmental component. The secondary device can comprise a sensor or sensing component (e.g., a biosensor). In other embodiments, microchip devices are provided for the controlled exposure of a reacting component, such as an enzyme. In still other embodiments, sensors are provided on the device outside of the reservoirs.

Abstract: A disposable biosensor for testing a fluid sample including a laminated strip with a first and second end, a reference electrode embedded in the laminated strip proximate to the first end, at least one working electrode embedded in the laminated strip proximate to the first end and the reference electrode, an open path for receiving a fluid sample beginning from the first end and connecting to a vent spaced from the first end, the open path being sufficiently long to expose the reference electrode and the working electrode to the fluid sample, and conductive contacts located at the second end of the laminated strip. The laminated strip has a base layer with a conductive coating, a reagent holding layer, a channel forming layer and a cover having an inlet notch at the first end. The working electrode contains a reagent having an enzyme.

Abstract: A disposable biosensor for testing a fluid sample including a laminated strip with a first and second end, a reference electrode embedded in the laminated strip proximate to the first end, at least one working electrode embedded in the laminated strip proximate to the first end and the reference electrode, an open path for receiving a fluid sample beginning from the first end and connecting to a vent spaced from the first end, the open path being sufficiently long to expose the reference electrode and the working electrode to the fluid sample, and conductive contacts located at the second end of the laminated strip. The laminated strip has a base layer with a conductive coating, a reagent holding layer, a channel forming layer and a cover having an inlet notch at the first end. The working electrode contains a reagent having an enzyme.

Abstract: An improved biosensor having at least a first working electrode and a first electrode material disposed on the first working electrode. The first electrode material is a mixture made by combining at least one enzyme where the at least one enzyme is a capable of reacting with the analyte to be measured, a redox mediator capable of reacting with a product of an enzymatic reaction or a series of enzymatic reactions involving the at least one enzyme, a peroxidase capable of catalyzing a reaction involving the redox mediator where the redox mediator is oxidized, a binder and a surfactant.

Abstract: An improved biosensor having at least a first working electrode and a first electrode material disposed on the first working electrode. The first electrode material is a mixture made by combining at least one enzyme where the at least one enzyme is a capable of reacting with the analyte to be measured, a redox mediator capable of reacting with a product of an enzymatic reaction or a series of enzymatic reactions involving the at least one enzyme, a peroxidase capable of catalyzing a reaction involving the redox mediator where the redox mediator is oxidized, a binder and a surfactant.

Abstract: An electrochemical sensor for detecting the presence and amount of acetate in cell culture and fermentation media. The electrochemical sensor has a pH electrode, an internal reference electrode, a special high-tensile strength gas permeable membrane, and internal reference electrolyte such that acetate concentration can be measured using a pretreatment buffer having a pH of about 5.5.

Abstract: A disposable electrode strip for testing a fluid sample including a laminated strip with a first and second end, a vent, an open path for receiving a fluid sample of less than one microliter beginning from the first end and connecting to the vent, a working electrode, a reference electrode and a pseudo-working electrode embedded in the laminated strip within the open path and proximate to the first end, a reagent matrix coextensive within the open path and covering the three electrodes, and conductive contacts located at the second end of the laminated strip.

Abstract: An improved biosensor having at least a first working electrode and a first electrode material disposed on the first working electrode. The first electrode material is a mixture made by combining at least one enzyme where the at least one enzyme is a capable of reacting with the analyte to be measured, a redox mediator capable of reacting with a product of an enzymatic reaction or a series of enzymatic reactions involving the at least one enzyme, a peroxidase capable of catalyzing a reaction involving the redox mediator where the redox mediator is oxidized, a binder and a surfactant.