Small volume in vitro analyte sensor
First Claim
1. An integrated piercing and sensing device for determining the concentration of analyte in a biological fluid from a patient, comprising:
- a sensor element adapted to be positioned adjacent to a site on the patient from which a biological fluid is to be collected to receive the biological fluid flowing from the site into a boundary area having a volume of less than about 1 μ
L;
a piercing element adapted to pierce a site on a patient to cause biological fluid to flow therefrom, the piercing element being movable in a parallel manner relative to said sensor element and comprising a piercing end on the same face of said device as said sensor element; and
an analyte measurement element operatively connected to said sensor element and adapted to measure the signal generated by said sensor element.
3 Assignments
0 Petitions
Accused Products
Abstract
A sensor designed to determine the amount and concentration of analyte in a sample having a volume of less than about 1 μL. The sensor has a working electrode coated with a non-leachable redox mediator. The redox mediator acts as an electron transfer agent between the analyte and the electrode. In addition, a second electron transfer agent, such as an enzyme, can be added to facilitate the electrooxidation or electroreduction of the analyte. The redox mediator is typically a redox compound bound to a polymer. The preferred redox mediators are air-oxidizable.
The amount of analyte can be determined by coulometry. One particular coulometric technique includes the measurement of the current between the working electrode and a counter or reference electrode at two or more times. The charge passed by this current to or from the analyte is correlated with the amount of analyte in the sample. Other electrochemical detection methods, such as amperometric, voltammetric, and potentiometric techniques, can also be used.
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. An enzyme capable of catalyzing the electrooxidation or electroreduction of the biomolecule is provided as a second electron transfer agent.
-
Citations
30 Claims
-
1. An integrated piercing and sensing device for determining the concentration of analyte in a biological fluid from a patient, comprising:
-
a sensor element adapted to be positioned adjacent to a site on the patient from which a biological fluid is to be collected to receive the biological fluid flowing from the site into a boundary area having a volume of less than about 1 μ
L;a piercing element adapted to pierce a site on a patient to cause biological fluid to flow therefrom, the piercing element being movable in a parallel manner relative to said sensor element and comprising a piercing end on the same face of said device as said sensor element; and an analyte measurement element operatively connected to said sensor element and adapted to measure the signal generated by said sensor element. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25)
-
-
26. An integrated piercing and sensing device for determining the concentration of glucose in blood from a patient, comprising:
-
a sensor element adapted to be positioned adjacent to a site on the patient from which blood is to be collected to receive the blood flowing from the site, wherein said sensor element comprises a working electrode and a counter electrode, wherein said working electrode comprises a glucose-responsive enzyme and a redox mediator and wherein said working electrode and said counter electrode are facing electrodes and are each positioned to contact blood in a boundary area receiving a volume of less than about 1 μ
L to generate an electrical signal indicative of the concentration of glucose in the blood;a piercing element adapted to pierce and retract from the site on the patient to cause blood to flow therefrom, said piercing element being movable in a parallel manner relative to said sensor element and comprising a piercing end on the same face of the device as said sensor element; and an analyte measurement element operatively connected to said sensor and adapted to measure the signal generated by said sensor.
-
-
27. A sample acquisition and analyte measuring device for determining the concentration of an analyte in a biological fluid of a patient, the apparatus comprising:
-
an analyte sensor element comprising a boundary area and an opening for transport of a biological fluid into said boundary area, said analyte sensor element being configured and arranged for determining the concentration of analyte in a biological fluid using an undiluted sample of biological fluid having a volume of less than about 1 μ
L , disposed thereof;a piercing member configured and arranged to pierce a site on the patient and then withdraw from said site to cause a flow of biological fluid from said site, the piercing element being movable in a parallel manner relative to said analyte sensor element and comprising a piercing end on the same face of the device as the opening of said analyte sensor element; and an analyte measurement element operatively connected to said sensor element and adapted to measure the signal generated by said sensor element.
-
-
28. A method for determining a concentration of an analyte in a biological fluid from a patient, the method comprising the steps of:
-
piercing a site on the patient with a piercing element of an integrated piercing and sensing device to cause said biological fluid to flow from the site, wherein the integrated piercing and sensing device comprises the piercing element, a sensor element, and an analyte measurement element, the piercing element being movable in a parallel manner relative to said sensor element and comprising a piercing end on the same face of the device as said sensor element, and the sensor element being operatively connected to the analyte measurement element and being adapted to be positioned adjacent to the site on the patient from which a biological fluid is to be collected to receive the biological fluid into a boundary area receiving a volume of less than about 1 μ
L to generate an electrical signal indicative of the concentration of analyte in said biological fluid;positioning said sensor element adjacent to said site on the patient such that said sensor element receives biological fluid flowing from said site; and measuring the signal generated by said sensor element using said analyte measurement element to determine the concentration of the analyte.
-
-
29. A method for determining a concentration of glucose in blood from a patient, the method comprising the steps of:
-
piercing a site on the patient with a piercing element of an integrated piercing and sensing device to cause blood to flow from the site, wherein the integrated piercing and sensing device comprises the piercing element, a sensor element, and an analyte measurement element, the piercing element being movable in a parallel manner relative to the sensor element and comprising a piercing end on the same face of the device as said sensor element, and the sensor element being operatively connected to the analyte measurement element and comprising a working electrode and a counter electrode, wherein said working electrode comprises a glucose-responsive enzyme and a redox mediator and wherein said working electrode and said counter electrode are facing electrodes and are each positioned to contact blood in a boundary area receiving a volume of less than about 1 μ
L to generate an electrical signal indicative of the concentration of glucose in blood;positioning said sensor element adjacent to said site on the patient such that said sensor element receives blood flowing from said site; measuring the signal generated by said sensor element using said analyte measurement element to determine the concentration of glucose.
-
-
30. A method for determining a concentration of an analyte in a biological fluid from a patient, the method comprising the steps of:
-
piercing a site on the patient with a piercing element of a sample acquisition and analyte measuring device to cause biological fluid to flow from the site, wherein the sample acquisition and analyte measuring device comprises the piercing element, an analyte sensor element, and an analyte measurement element, the piercing element comprising a piercing end and being movable in a parallel manner relative to the analyte sensor element, and the analyte sensor element being operatively connected to said analyte measurement element and comprising a boundary area and an opening for transport of biological fluid into said boundary area that is on the same face of the device as the piercing end of said piercing element, wherein the analyte sensor element is configured and arranged for determining the concentration of analyte in a biological fluid using an undiluted sample of biological fluid having a volume of less than about 1 μ
L disposed thereof;positioning the opening of the sensor element adjacent to the site on the patient; and measuring the signal generated by the sensor element using the analyte measurement element to determine the concentration of the analyte.
-
Specification