Electrochemical method for measuring chemical reaction rates
First Claim
Patent Images
1. A method for measuring a rate of a chemical reaction between a component of a liquid sample and a reagent, the reaction producing an electroactive species, comprising:
- providing an electrochemical cell having a working electrode, a counter electrode, and at least one wall, wherein the working electrode and the counter electrode are positioned on substantially the same plane;
substantially immobilizing the reagent in the electrochemical cell at a site at a minimum distance from the working electrode, wherein the distance is such that transfer of the electroactive species from the site to the working electrode is diffusion controlled;
placing the liquid sample in the electrochemical cell such that the liquid sample is in contact with the reagent, the working electrode, and the counter electrode;
reacting the component with the reagent to produce the electroactive species;
applying a potential between the working electrode and the counter electrode, wherein the potential is sufficient to electrochemically react the electroactive species at the working electrode; and
measuring the current produced by the electrochemical reaction at the working electrode to obtain a measure of the rate of the chemical reaction.
7 Assignments
0 Petitions
Accused Products
Abstract
The present invention relates to the measurement of the progress of a chemical reaction that generates an electroactive reaction product that is subsequently detected at an electrode amperometrically or coulometrically. The method is useful in applications where it is desirable to follow the progress of a chemical reaction, particularly in sensor applications where the progress of the reaction of an analyte can be useful in determining the analyte concentration.
-
Citations
32 Claims
-
1. A method for measuring a rate of a chemical reaction between a component of a liquid sample and a reagent, the reaction producing an electroactive species, comprising:
-
providing an electrochemical cell having a working electrode, a counter electrode, and at least one wall, wherein the working electrode and the counter electrode are positioned on substantially the same plane; substantially immobilizing the reagent in the electrochemical cell at a site at a minimum distance from the working electrode, wherein the distance is such that transfer of the electroactive species from the site to the working electrode is diffusion controlled; placing the liquid sample in the electrochemical cell such that the liquid sample is in contact with the reagent, the working electrode, and the counter electrode; reacting the component with the reagent to produce the electroactive species; applying a potential between the working electrode and the counter electrode, wherein the potential is sufficient to electrochemically react the electroactive species at the working electrode; and measuring the current produced by the electrochemical reaction at the working electrode to obtain a measure of the rate of the chemical reaction. - 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, 27, 28, 29, 30, 31)
-
-
32. A method for measuring a rate of a chemical reaction between glucose and PQQ dependent glucose dehydrogenase in whole blood comprising:
-
providing an electrochemical cell having a working electrode, a counter electrode, at least one wall, a redox mediator comprising ferricyanide and contained within the electrochemical cell, and a reagent comprising PQQ dependent glucose dehydrogenase, the reagent being substantially immobilized in the electrochemical cell at a site at a minimum distance from the working electrode, wherein the working electrode and the counter electrode are positioned on substantially the same plane; placing the whole blood sample in the electrochemical cell such that the sample is in contact with the reagent, the redox mediator, the working electrode, and the counter electrode; reacting the glucose with the PQQ dependent glucose dehydrogenase to produce reduced PQQ dependent glucose dehydrogenase, the reduced PQQ dependent glucose dehydrogenase in turn reacting with the ferricyanide redox mediator to form ferrocyanide;
applying a potential between the working electrode and the counter electrode, wherein the potential is sufficient to electrochemically react the ferrocyanide at the working electrode; andmeasuring the current produced by the electrochemical reaction of ferrocyanide at the working electrode, wherein the measurement is indicative of the rate of the chemical reaction between glucose and PQQ dependent glucose dehydrogenase.
-
Specification