Small Volume In Vitro Sensor and Methods of Making
2 Assignments
0 Petitions
Accused Products
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.
-
Citations
42 Claims
-
1-11. -11. (canceled)
-
12. A sensor for determining a concentration of glucose in a sample, the sensor comprising:
-
a first substrate having a proximal end and a distal end, the first substrate defining a first side edge and a second side edge of the sensor extending from the proximal end to the distal end of the first substrate, the distal end being configured and arranged for insertion into a sensor reader; a second substrate disposed over the first substrate; a spacer disposed between the first and second substrates and defining a first aperture along the first side edge of the sensor, a second aperture along the second side edge of the sensor, and a sample chamber extending from the first aperture to the second aperture; a working electrode disposed on at least one of the first and second substrates; a FAD-dependent glucose dehydrogenase disposed on the working electrode; a counter electrode disposed on at least one of the first and second substrates, wherein the working electrode and the counter electrode are positioned relative to the sample chamber to generate a glucose-responsive signal when sample containing glucose is disposed in the sample chamber; and an indicator electrode disposed on at least one of the first and second substrates and positioned relative to a sample flow path within the sample chamber to indicate that, when sample contacts the indicator electrode, the sample chamber is filled with sample. - View Dependent Claims (13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32)
-
-
33. A sensor for determining a concentration of glucose in a sample, the sensor comprising:
-
a first substrate having a proximal end and a distal end, the distal end being configured and arranged for insertion into a sensor reader, the first substrate defining a first side edge and a second side edge of the sensor extending from the proximal end to the distal end of the first substrate; a second substrate disposed over the first substrate; a spacer disposed between the first and second substrates and defining a first aperture along the proximal end of the sensor, a second aperture along the first side edge of the sensor, and a sample chamber extending from the first aperture to the second aperture; a working electrode disposed on at least one of the first and second substrates; a FAD-dependent glucose dehydrogenase disposed on the working electrode; a counter electrode disposed on at least one of the first and second substrates, wherein the working electrode and the counter electrode are positioned relative to the sample chamber to generate a glucose-responsive signal when sample containing glucose is disposed in the sample chamber; and an indicator electrode disposed on at least one of the first and second substrates and positioned relative to the sample chamber to determine when the sample chamber contains sample. - View Dependent Claims (34)
-
-
35. A sensor for determining a concentration of glucose in a sample, the sensor comprising:
-
a first substrate having a proximal end and a distal end, the distal end being configured and arranged for insertion into a sensor reader, the first substrate defining a first side edge and a second side edge of the sensor extending from the proximal end to the distal end of the first substrate; a second substrate disposed over the first substrate; a spacer disposed between the first and second substrates and defining a first aperture along the first side edge of the sensor, a second aperture along the second side edge of the sensor, and a sample chamber extending from the first aperture to the second aperture; a working electrode disposed on the first substrate; a FAD-dependent glucose dehydrogenase disposed on the working electrode; a counter electrode disposed on the second substrate, wherein the working electrode and the counter electrode are positioned relative to the sample chamber to generate a glucose-responsive signal when sample containing glucose is disposed in the sample chamber; and an indicator electrode disposed on at least one of the first and second substrates and positioned relative to the sample chamber to determine when the sample chamber contains sample.
-
-
36. A sensor for determining a concentration of glucose in a sample, the sensor comprising:
-
a first substrate having a proximal end and a distal end, the first substrate defining a first side edge and a second side edge of the sensor extending from the proximal end to the distal end of the first substrate, the distal end being configured and arranged for insertion into a sensor reader; a second substrate disposed over the first substrate; a spacer disposed between the first and second substrates and defining a first aperture along the first side edge of the sensor, a second aperture along the second side edge of the sensor, and a sample chamber extending from the first aperture to the second aperture; a working electrode disposed on at least one of the first and second substrates; a FAD-dependent glucose dehydrogenase disposed on the working electrode; a counter electrode disposed on at least one of the first and second substrates, wherein the working electrode and the counter electrode are positioned relative to the sample chamber to generate a glucose-responsive signal when sample containing glucose is disposed in the sample chamber; and an indicator electrode disposed on at least one of the first and second substrates wherein the indicator electrode is configured and arranged to aid in electrolysis of the glucose.
-
-
37. A sensor for determining a concentration of glucose in a sample, the sensor comprising:
-
a first substrate having a proximal end and a distal end, the distal end being configured and arranged for insertion into a sensor reader, the first substrate defining a first side edge and a second side edge of the sensor extending from the proximal end to the distal end of the first substrate; a second substrate disposed over the first substrate; a spacer disposed between the first and second substrates and defining a first aperture along the first side edge of the sensor, a second aperture along the second side edge of the sensor, and a sample chamber extending from the first aperture to the second aperture; a working electrode disposed on the first substrate; a FAD-dependent glucose dehydrogenase disposed on the working electrode; a counter electrode disposed on the second substrate, wherein the working electrode and the counter electrode are positioned relative to the sample chamber to generate a glucose-responsive signal when sample containing glucose is disposed in the sample chamber; and an indicator electrode disposed on at least one of the first and second substrates, wherein the indicator electrode comprises first and second indicator electrodes, the first indicator electrode is positioned relative to the sample chamber to determine when the sample chamber begins to fill with sample and the second indicator electrode is positioned relative to the sample chamber to determine when the sample chamber is filled with sample.
-
-
38. A method of monitoring glucose using an electrochemical sensor, the method comprising:
-
contacting a sample with an aperture defined between two substrates of an electrochemical sensor comprising a working electrode disposed on a one of the two substrates, and a FAD-dependent glucose dehydrogenase disposed on the working electrode; drawing at least a portion of the sample through the aperture and into a sample chamber disposed between the two substrates; observing an indicator electrode disposed on a one of the two substrates, wherein the indicator electrode is positioned within the sensor to indicate, when the sample contacts the working electrode and then subsequently contacts the indicator electrode, that the sample chamber is sufficiently full for monitoring the glucose using the sensor; and generating a glucose-responsive signal using the working electrode and a counter electrode disposed on a one of the two substrates, wherein the working electrode and a counter electrode are separate from the indicator electrode and are disposed in electrolytic contact with the sample chamber. - View Dependent Claims (39, 40, 41, 42)
-
Specification