Potentiometric biosensor and the method of its use

Claim 2

A potentiometric biosensor for analysis of an analyte from a fluid sample, comprising: a. an indicating electrode; b. a reference electrode; c. a reagent of known amount overlaying a portion of the surface of the indicating electrode and comprising a redox mediator, the redox mediator being in an amount to react with all of the analyte at the surface of the indicating electrode, thereby causing a measurable change in potential that correlates to the change in proportions of the oxidized and reduced forms of the redox mediator at the surface of the indicating electrode; and d. a potentiometer in electrical connection with the indicating and reference electrodes.

Claim 3

A potentiometric biosensor, comprising: a. an indicating electrode; b. a reference electrode; c. a reagent of known amount overlaying a portion of the surface of the indicating electrode and comprising a catalyst and a redox mediator, the catalyst being in an amount to catalyze a reaction involving the catalyst, the redox mediator, and an analyte from a fluid sample, the redox mediator being in an amount to react with all of the analyte at the surface of the indicating electrode, thereby causing a measurable change in potential that correlates to the change in proportions of the oxidized and reduced forms of the redox mediator at the surface of the indicating electrode; and d. a potentiometer in electrical connection with the indicating and reference electrodes.

Claim 4

A potentiometric biosensor, comprising: a. an indicating electrode; b. a reference electrode; c. a reagent of known amount overlaying a portion of the surface of the indicating electrode and comprising a catalyst and a redox mediator, the catalyst being in an amount to catalyze a reaction involving the catalyst, the redox mediator, and an analyte from a fluid sample, the redox mediator being in an amount to react with all of the analyte at the surface of the indicating electrode, thereby causing a measurable change in potential that correlates to the change in proportions of the oxidized and reduced forms of the redox mediator at the surface of the indicating electrode; and d. a potentiometer in electrical connection with the indicating and reference electrodes.

Claim 5

A potentiometric biosensor, comprising: a. an indicating electrode; b. a reference electrode; c. a reagent of known amount overlaying a portion of the surface of the indicating electrode and comprising an enzyme and a redox mediator, the enzyme being in an amount to catalyze a reaction involving the enzyme, the redox mediator, and an analyte from a fluid sample, the redox mediator being in an amount to react with all of the analyte at the surface of the indicating electrode, thereby causing a measurable change in potential that correlates to the change in proportions of the oxidized and reduced forms of the redox mediator at the surface of the indicating electrode; and d. a potentiometer in electrical connection with the indicating and reference electrodes.

Claim 6

A potentiometric biosensor, comprising: a. an indicating electrode; b. a reference electrode; c. a reagent of known amount overlaying a portion of the surface of the indicating electrode and comprising an enzyme and a redox mediator, the enzyme being in an amount to catalyze a reaction involving the enzyme, the redox mediator, and an analyte from a fluid sample, the redox mediator being in an amount to react with all of the analyte at the surface of the indicating electrode, thereby causing a measurable change in potential that correlates to the change in proportions of the oxidized and reduced forms of the redox mediator at the surface of the indicating electrode; and d. a potentiometer in electrical connection with the indicating and reference electrodes.

Claim 7

A potentiometric method of detecting an analyte from a fluid sample, comprising the steps of: a. forming a test sample by adding the fluid sample to the potentiometric biosensor of claim 1, wherein the reagent is fully exposed to the fluid sample and the fluid sample contacts both the indicating and the reference electrodes, thereby forming a circuit; b. incubating the test sample to produce the measurable change in potential that correlates to the change in proportions of the oxidized and reduced forms of the redox mediator at the surface of the indicating electrode; c. measuring potential after incubation; and d. correlating the measured potential to detection of the analyte.

Claim 8

A potentiometric method of measuring an analyte from a fluid sample, comprising the steps of: a. forming a test sample by adding the fluid sample to a potentiometric biosensor including, 1) a first electrical insulator,. 2) indicating and reference electrodes supported on the first electrical insulator, 3) a second electrical insulator, overlaying the first electrical insulator and the electrodes and including a cutout portion that exposes surface areas of the indicating and reference electrodes, 4) a reagent of known amount overlaying the exposed surface of the indicating electrode in the cutout portion and comprising a redox mediator, the redox mediator being in sufficient amount to react with all of the analyte at the surface of the indicating electrode, thereby causing a measurable change in potential that correlates to the change in proportions of the oxidized and reduced forms of the redox mediator at the surface of the indicating electrode, and 5) a potentiometer in electrical connection with the indicating and reference electrodes, wherein the reagent is fully exposed to the fluid sample and the fluid sample contacts both the indicating and reference electrodes, thereby forming a circuit; b. incubating the test sample to produce the measurable change in potential that correlates to the change in proportions of the oxidized and reduced forms of the redox mediator at the surface of the indicating electrode; c. measuring potential after incubation; and d. correlating the measured potential to the amount of the analyte in the fluid sample.

Claim 9

A potentiometric method of measuring an analyte from a fluid sample, comprising the steps of: a. forming a test sample by adding the fluid sample to a potentiometric biosensor including, 1) a first electrical insulator,. 2) indicating and reference electrodes supported on the first electrical insulator, 3) a second electrical insulator, overlaying the first electrical insulator and the electrodes and including a cutout portion that exposes surface areas of the indicating and reference electrodes, 4) a reagent of known amount overlaying the exposed surface of the indicating electrode in the cutout portion and comprising a redox mediator, the redox mediator being in sufficient amount to react with all of the analyte at the surface of the indicating electrode, thereby causing a measurable change in potential that correlates to the change in proportions of the oxidized and reduced forms of the redox mediator at the surface of the indicating electrode, and 5) a potentiometer in electrical connection with the indicating and reference electrodes, wherein the reagent is fully exposed to the fluid sample and the fluid sample contacts both the indicating and reference electrodes, thereby forming a circuit; b. incubating the test sample to produce the measurable change in potential that correlates to the change in proportions of the oxidized and reduced forms of the redox mediator at the surface of the indicating electrode; c. measuring potential after incubation; and d. correlating the measured potential to the amount of the analyte in the fluid sample.

Claim 10

A potentiometric method of detecting an analyte from a fluid sample, comprising the steps of: a. forming a test sample by adding the fluid sample to the potentiometric biosensor of claim 2, wherein the reagent is fully exposed to the fluid sample and the fluid sample contacts both the indicating and the reference electrodes, thereby forming a circuit; b. incubating the test sample to produce the measurable change in potential that correlates to the change in proportions of the oxidized and reduced forms of the redox mediator at the surface of the indicating electrode; c. measuring potential after incubation; and d. correlating the measured potential to detection of the analyte.

Claim 11

A potentiometric method of measuring an analyte from a fluid sample, comprising the steps of: a. forming a test sample by adding the fluid sample to a potentiometric biosensor including, 1) a first electrical insulator, 2) indicating and reference electrodes supported on the first electrical insulator, 3) a second electrical insulator, overlaying the first electrical insulator and the electrodes and including a cutout portion that exposes surface areas of the indicating and reference electrodes, 4) a reagent of known amount overlaying the exposed surface of the indicating electrode in the cutout portion and comprising a catalyst, a buffer, and a redox mediator, the catalyst being in an amount to catalyze a reaction involving the catalyst, the redox mediator, and an analyte from the fluid sample, the buffer being in an amount to provide and maintain a pH at which the catalyst catalyzes the reaction involving the catalyst, the redox mediator, and the analyte, the redox mediator being in an amount to react with all of the analyte at the surface of the indicating electrode, thereby causing a measurable change in potential that correlates to the change in proportions of the oxidized and reduced forms of the redox mediator at the surface of the indicating electrode, and 5) a potentiometer in electrical connection with the indicating and reference electrodes, wherein the reagent is fully exposed to the fluid sample and the fluid sample contacts both the indicating and reference electrodes, thereby forming a circuit; b. incubating the test sample to produce the measurable change in potential that correlates to the change in proportions of the oxidized and reduced forms of the redox mediator at the surface of the indicating electrode; c. measuring potential after incubation; and d. correlating the measured potential to the amount of the analyte in the fluid sample.

Claim 12

A potentiometric method of measuring an analyte from a fluid sample, comprising the steps of: a. forming a test sample by adding the fluid sample to a potentiometric biosensor including, 1) a first electrical insulator, 2) indicating and reference electrodes supported on the first electrical insulator, 3) a second electrical insulator, overlaying the first electrical insulator and the electrodes and including a cutout portion that exposes surface areas of the indicating and reference electrodes, 4) a reagent of known amount overlaying the exposed surface of the indicating electrode in the cutout portion and comprising a catalyst, a buffer, and a redox mediator, the catalyst being in an amount to catalyze a reaction involving the catalyst, the redox mediator, and an analyte from the fluid sample, the buffer being in an amount to provide and maintain a pH at which the catalyst catalyzes the reaction involving the catalyst, the redox mediator, and the analyte, the redox mediator being in an amount to react with all of the analyte at the surface of the indicating electrode, thereby causing a measurable change in potential that correlates to the change in proportions of the oxidized and reduced forms of the redox mediator at the surface of the indicating electrode, and 5) a potentiometer in electrical connection with the indicating and reference electrodes, wherein the reagent is fully exposed to the fluid sample and the fluid sample contacts both the indicating and reference electrodes, thereby forming a circuit; b. incubating the test sample to produce the measurable change in potential that correlates to the change in proportions of the oxidized and reduced forms of the redox mediator at the surface of the indicating electrode; c. measuring potential after incubation; and d. correlating the measured potential to the amount of the analyte in the fluid sample.

Claim 13

A potentiometric method of detecting an analyte from a fluid sample, comprising the steps of: a. forming a test sample by adding the fluid sample to a potentiometric biosensor including, 1) a first electrical insulator, 2) indicating and reference electrodes supported on the first electrical insulator, 3) a second electrical insulator, overlaying the first electrical insulator and the electrodes and including a cutout portion that exposes surface areas of the indicating and reference electrodes, 4) a reagent of known amount overlaying the exposed surface of the indicating electrode in the cutout portion and comprising an enzyme, a buffer, and a redox mediator, the enzyme being in an amount to catalyze a reaction involving the enzyme, the redox mediator, and an analyte from the fluid sample, the buffer being in an amount to provide and. maintain a pH at which the enzyme catalyzes the reaction involving the enzyme, the redox mediator, and the analyte, the redox mediator being in an amount to react with all of the analyte at the surface of the indicating electrode, thereby causing a measurable change in potential that correlates to the change in proportions of the oxidized and reduced forms of the redox mediator at the surface of the indicating electrode, and 5) a potentiometer in electrical connection with the indicating and reference wherein the reagent is fully exposed to the fluid sample and the fluid sample contacts both the indicating and reference electrodes, thereby forming a circuit; b. incubating the test sample to produce the measurable change in potential that correlates to the change in proportions of the oxidized and reduced forms of the redox mediator at the surface of the indicating electrode; c. measuring potential after incubation; and d. correlating the measured potential to the detection of the analyte.

Claim 14

A potentiometric method of detecting an analyte from a fluid sample, comprising the steps of: a. forming a test sample by adding the fluid sample to a potentiometric biosensor including, 1) a first electrical insulator, 2) indicating and reference electrodes supported on the first electrical insulator, 3) a second electrical insulator, overlaying the first electrical insulator and the electrodes and including a cutout portion that exposes surface areas of the indicating and reference electrodes, 4) a reagent of known amount overlaying the exposed surface of the indicating electrode in the cutout portion and comprising an enzyme, a buffer, and a redox mediator, the enzyme being in an amount to catalyze a reaction involving the enzyme, the redox mediator, and an analyte from the fluid sample, the buffer being in an amount to provide and. maintain a pH at which the enzyme catalyzes the reaction involving the enzyme, the redox mediator, and the analyte, the redox mediator being in an amount to react with all of the analyte at the surface of the indicating electrode, thereby causing a measurable change in potential that correlates to the change in proportions of the oxidized and reduced forms of the redox mediator at the surface of the indicating electrode, and 5) a potentiometer in electrical connection with the indicating and reference wherein the reagent is fully exposed to the fluid sample and the fluid sample contacts both the indicating and reference electrodes, thereby forming a circuit; b. incubating the test sample to produce the measurable change in potential that correlates to the change in proportions of the oxidized and reduced forms of the redox mediator at the surface of the indicating electrode; c. measuring potential after incubation; and d. correlating the measured potential to the detection of the analyte.

Claim 15

A potentiometric method of measuring an analyte from a fluid sample, comprising the steps of: a. forming a test sample by adding the fluid sample to a potentiometric biosensor including, 1) a first electrical insulator, 2) indicating and reference electrodes supported on the first electrical insulator, 3) a second electrical insulator, overlaying the first electrical insulator and the electrodes and including a cutout portion that exposes surface areas of the indicating and reference electrodes, 4) a reagent of known amount overlaying the exposed surface of the indicating electrode in the cutout portion and comprising an enzyme, a buffer, and a redox mediator, the enzyme being in an amount to catalyze reaction involving the enzyme, the redox mediator, and an analyte from the fluid sample, the buffer being in an amount to provide and maintain a pH at which the enzyme catalyzes the reaction involving the enzyme, the redox mediator, and the analyte, the redox mediator being in an amount to react with all of the analyte at the surface of the indicating electrode, thereby causing a measurable change in potential that correlates to the change in proportions of the and reduced forms of the redox mediator at the surface of the indicating electrode, and 5) a potentiometer in electrical connection with the indicating and reference electrodes, wherein the reagent is fully exposed to the fluid sample and the fluid sample contacts both the indicating and reference electrodes, thereby forming a circuit; b. incubating the test sample to produce the measurable change in potential that correlates to the change in proportions of the oxidized and reduced forms of the redox mediator at the surface of the indicating electrode; c. measuring potential after incubation; and d. correlating the measured potential to the amount of the analyte in the fluid sample.

Claim 16

A potentiometric method of measuring an analyte from a fluid sample, comprising the steps of: a. forming a test sample by adding the fluid sample to a potentiometric biosensor including, 1) a first electrical insulator, 2) indicating and reference electrodes supported on the first electrical insulator, 3) a second electrical insulator, overlaying the first electrical insulator and the electrodes and including a cutout portion that exposes surface areas of the indicating and reference electrodes, 4) a reagent of known amount overlaying the exposed surface of the indicating electrode in the cutout portion and comprising an enzyme, a buffer, and a redox mediator, the enzyme being in an amount to catalyze reaction involving the enzyme, the redox mediator, and an analyte from the fluid sample, the buffer being in an amount to provide and maintain a pH at which the enzyme catalyzes the reaction involving the enzyme, the redox mediator, and the analyte, the redox mediator being in an amount to react with all of the analyte at the surface of the indicating electrode, thereby causing a measurable change in potential that correlates to the change in proportions of the and reduced forms of the redox mediator at the surface of the indicating electrode, and 5) a potentiometer in electrical connection with the indicating and reference electrodes, wherein the reagent is fully exposed to the fluid sample and the fluid sample contacts both the indicating and reference electrodes, thereby forming a circuit; b. incubating the test sample to produce the measurable change in potential that correlates to the change in proportions of the oxidized and reduced forms of the redox mediator at the surface of the indicating electrode; c. measuring potential after incubation; and d. correlating the measured potential to the amount of the analyte in the fluid sample.

Claim 17

A potentiometric method of measuring an analyte from a fluid sample, comprising the steps of: a. forming a test sample by adding the fluid sample to the potentiometric biosensor of claim 3, wherein the reagent is fully exposed to the fluid sample and the fluid sample contacts both the indicating and reference electrodes, thereby forming a circuit; b. incubating the test sample to produce the measurable change in potential that correlates to the change in proportions of the oxidized and reduced forms of the redox mediator at the surface of the indicating electrode; c. measuring potential after incubation; and d. correlating the measured potential to the amount of the analyte in the fluid sample.

Claim 18

A potentiometric biosensor for analysis of an analyte from a fluid sample, comprising: a. a first electrical insulator; b. indicating and reference electrodes supported on the first electrical insulator; c. a second electrical insulator, overlaying the first electrical insulator and the electrodes and including a cutout portion that exposes surface areas of the indicating and reference electrodes; d. a reagent of known amount overlaying the exposed surface of the indicating electrode in the cutout portion and comprising a redox mediator, the redox mediator being in an amount to react with all of the analyte at the surface of the indicating electrode, thereby causing a measurable change in potential that correlates to the change in proportions of the oxidized and reduced forms of the redox mediator at the surface of the indicating electrode; and e. a potentiometer in electrical connection with the indicating and reference electrodes.

Claim 19

A potentiometric biosensor for analysis of an analyte from a fluid sample, comprising: a. a first electrical insulator; b. indicating and reference electrodes supported on the first electrical insulator; c. a second electrical insulator, overlaying the first electrical insulator and the electrodes and including a cutout portion that exposes surface areas of the indicating and reference electrodes; d. a reagent of known amount overlaying the exposed surface of the indicating electrode in the cutout portion and comprising a redox mediator, the redox mediator being in an amount to react with all of the analyte at the surface of the indicating electrode, thereby causing a measurable change in potential that correlates to the change in proportions of the oxidized and reduced forms of the redox mediator at the surface of the indicating electrode; and e. a potentiometer in electrical connection with the indicating and reference electrodes.

Claim 20

The potentiometric biosensor of claim 11, wherein the reagent further comprises a dispersant and crystallization inhibitor and a thickener.

Claim 21

A potentiometric biosensor, comprising: a. a first electrical insulator; b. indicating and reference electrodes supported on the first electrical insulator; c. a second electrical insulator, overlaying the first electrical insulator and the electrodes and including a cutout portion that exposes surface areas of the indicating and reference electrodes; d. a reagent of known amount overlaying the exposed surface of the indicating electrode in the cutout portion and comprising a catalyst and a redox mediator, the catalyst being in an amount to catalyze a reaction involving the catalyst, the redox mediator, and an analyte from a fluid sample, the redox mediator being in an amount to react with all of the analyte at the surface of the indicating electrode, thereby causing a measurable change in potential that correlates to the change in proportions of the oxidized and reduced forms of the redox mediator at the surface of the indicating electrode; and e. a potentiometer in electrical connection with the indicating and reference electrodes.

Claim 22

A potentiometric biosensor, comprising: a. a first electrical insulator; b. indicating and reference electrodes supported on the first electrical insulator; c. a second electrical insulator, overlaying the first electrical insulator and the electrodes and including a cutout portion that exposes surface areas of the indicating and reference electrodes; d. a reagent of known amount overlaying the exposed surface of the indicating electrode in the cutout portion and comprising a catalyst and a redox mediator, the catalyst being in an amount to catalyze a reaction involving the catalyst, the redox mediator, and an analyte from a fluid sample, the redox mediator being in an amount to react with all of the analyte at the surface of the indicating electrode, thereby causing a measurable change in potential that correlates to the change in proportions of the oxidized and reduced forms of the redox mediator at the surface of the indicating electrode; and e. a potentiometer in electrical connection with the indicating and reference electrodes.

Claim 23

The potentiometric biosensor of claim 13, wherein the reagent further comprises a buffer in sufficient amount to provide and maintain a pH at which the catalyst catalyzes the reaction involving the catalyst, the redox mediator, and the analyte.

Claim 24

A potentiometric biosensor, comprising: a. a first electrical insulator; b. indicating and reference electrodes supported on the first electrical insulator; c. a second electrical insulator, overlaying the first electrical insulator and the electrodes and including a cutout portion that exposes surface areas of the indicating and reference electrodes; d. a reagent of known amount overlaying the exposed surface of the indicating electrode in the cutout portion and comprising an enzyme and a redox mediator, the enzyme being in an amount to catalyze a reaction involving the enzyme, the redox mediator, and an analyte from a fluid sample, the redox mediator being in an amount to react with all of the analyte at the surface of the indicating electrode, thereby causing a measurable change in potential that correlates to the change in proportions of the oxidized and reduced forms of the redox mediator at the surface of the indicating electrode; and e. a potentiometer in electrical connection with the indicating and reference electrodes.

Claim 25

A potentiometric biosensor, comprising: a. a first electrical insulator; b. indicating and reference electrodes supported on the first electrical insulator; c. a second electrical insulator, overlaying the first electrical insulator and the electrodes and including a cutout portion that exposes surface areas of the indicating and reference electrodes; d. a reagent of known amount overlaying the exposed surface of the indicating electrode in the cutout portion and comprising an enzyme and a redox mediator, the enzyme being in an amount to catalyze a reaction involving the enzyme, the redox mediator, and an analyte from a fluid sample, the redox mediator being in an amount to react with all of the analyte at the surface of the indicating electrode, thereby causing a measurable change in potential that correlates to the change in proportions of the oxidized and reduced forms of the redox mediator at the surface of the indicating electrode; and e. a potentiometer in electrical connection with the indicating and reference electrodes.

Claim 26

The potentiometric biosensor of claim 15, wherein the reagent further comprises a buffer in an amount to provide and maintain a pH at which the enzyme catalyzes the reaction involving the enzyme, the redox mediator, and the analyte.

Claim 27

The potentiometric biosensor of claim 15, wherein the indicating electrode is selected from a group consisting of palladium, platinum, gold, silver, titanium, copper, and carbon.