MEDIATOR STABILIZED REAGENT COMPOSITIONS AND METHODS FOR THEIR USE IN ELECTROCHEMICAL ANALYTE DETECTION ASSAYS

PURPOSE: Mediator stabilized reagent compositions and methods for their use in electrochemical analyte detection assays are provided, which mediator stabilized reagent compositions are compositions that find use in electrochemical analyte detection devices, are typical redox reagent compositions, and are meant a composition in which the mediator component of the composition does not convert to a reduced form for an extended period of time under typical storage conditions. CONSTITUTION: The mediator stabilized reagent composition comprises (a) an enzyme; (b) a redox mediator; and (c) a mediator-stabilizing buffer present in an amount sufficient to storage stabilize the redox mediator, wherein the buffer comprises a polycarboxylic acid; the polycarboxylic acid has at least two carboxylic acid groups, mellitic acid and salts thereof, or citraconic acid and salts thereof. An electrochemical cell comprising the mediator stabilized reagent composition, wherein the cell is present in an electrochemical test strip. A method for determining the concentration of an analyte in a sample comprises (a) applying the sample to an electrochemical cell comprising the mediator stabilized reagent composition; (b) detecting an electrical signal produced by the cell; and (c) relating the detected electrical signal to the concentration of the analyte in the sample.