Abstract: An electrochemical test device for use in determining a concentration of each of a first analyte and a second analyte in a fluid sample is provided. The electrochemical test device comprises a set of electrodes including a first working electrode having sensing chemistry for the first analyte and a second working electrode having sensing chemistry for the second analyte, wherein the first analyte is lactate and the sensing chemistry for the lactate comprises lactate oxidase and an electron transfer agent, and wherein the sensing chemistry for the second analyte comprises a diaphorase, an electron transfer agent, an NAD(P)+-dependent dehydrogenase and a cofactor for the NAD(P)+-dependent dehydrogenase.

Abstract: A composition is provided. The composition comprises an enzyme and a ruthenium- or osmium-based electron transfer agent, wherein the ruthenium- or osmium-based electron transfer agent is a complex [M(A)x(B)y](X)n wherein M is ruthenium or osmium; A is an amine ligand; each B is a ligand different to A; x is an integer selected from 1 to 5; y is an integer selected from 1 to 5; x+y is 6 or 8; n is an integer selected from 1 to 6; and X is any suitable counterion.

Abstract: An electrochemical test device for determining a concentration of an analyte in a fluid sample is provided. The electrochemical test device comprises a set of electrodes including a working electrode for the analyte and sensing chemistry for the working electrode, wherein the sensing chemistry comprises a diaphorase, an electron transfer agent having a standard redox potential in the range of ?0.52 to 0.18 V, an NAD(P)+-dependent dehydrogenase and a cofactor for the NAD(P)+-dependent dehydrogenase.

Abstract: An electrochemical test device for determining a concentration of one or more analytes in a fluid sample is provided. The electrochemical test device comprises a set of electrodes including two or more working electrodes, each working electrode for determining the concentration of a corresponding analyte, and sensing chemistry for each working electrode, wherein the sensing chemistry for a first of the two or more working electrodes comprises a diaphorase, an electron transfer agent, an NAD(P)+-dependent dehydrogenase and a cofactor for the NAD(P)+-dependent dehydrogenase, wherein at least some of the diaphorase for the first working electrode is disposed in a diaphorase-containing layer which extends over the first working electrode and at least a second of the two or more working electrodes.

Abstract: An electrochemical test device for use in determining a concentration of each of a first analyte and a second analyte in a fluid sample is provided. The electrochemical test device comprises a set of electrodes including a first working electrode having sensing chemistry for the first analyte and a second working electrode having sensing chemistry for the second analyte, wherein the first analyte is lactate and the sensing chemistry for the lactate comprises lactate oxidase and an electron transfer agent, and wherein the sensing chemistry for the second analyte comprises a diaphorase, an electron transfer agent, an NAD(P)+-dependent dehydrogenase and a cofactor for the NAD(P)+-dependent dehydrogenase.

Abstract: An electrochemical test device for determining a concentration of an analyte in a fluid sample is provided. The electrochemical test device comprises a set of electrodes including a working electrode for the analyte and sensing chemistry for the working electrode, wherein the sensing chemistry comprises a diaphorase, an electron transfer agent having a standard redox potential in the range of ?0.52 to 0.18 V, an NAD(P)+-dependent dehydrogenase and a cofactor for the NAD(P)+-dependent dehydrogenase.

Abstract: An electrochemical test device for determining a concentration of one or more analytes in a fluid sample is provided. The electrochemical test device comprises a set of electrodes including two or more working electrodes, each working electrode for determining the concentration of a corresponding analyte, and sensing chemistry for each working electrode, wherein the sensing chemistry for a first of the two or more working electrodes comprises a diaphorase, an electron transfer agent, an NAD(P)+-dependent dehydrogenase and a cofactor for the NAD(P)+-dependent dehydrogenase, wherein at least some of the diaphorase for the first working electrode is disposed in a diaphorase-containing layer which extends over the first working electrode and at least a second of the two or more working electrodes.

Abstract: An electrochemical test device for determining a concentration of an analyte in a fluid sample is provided. The electrochemical test device comprises a set of electrodes including a working electrode for the analyte and sensing chemistry for the working electrode, wherein the sensing chemistry is disposed on the working electrode in at least one layer, each layer comprising a diaphorase, an electron transfer agent having a standard redox potential in the range of ?0.52 to 0.18 V, an NAD(P)+-dependent dehydrogenase and a cofactor for the NAD(P)+-dependent dehydrogenase.

Abstract: A composition is provided. The composition comprises an enzyme and a ruthenium- or osmium-based electron transfer agent, wherein the ruthenium- or osmium-based electron transfer agent is a complex [M(A)x(B)y] (X)n wherein M is ruthenium or osmium; A is an amine ligand; each B is a ligand different to A; x is an integer selected from 1 to 5; y is an integer selected from 1 to 5; x+y is 6 or 8; n is an integer selected from 1 to 6; and X is any suitable counterion.