Patent ID: 6338790
Filing Date: 2002-01-15
Classification: C12Q,G01N,Y10T

Abstract:
A sensor for determining the concentration of an analyte in a sample fluid, the sensor comprising:an electrode pair comprising a working electrode and a counter electrode, wherein at least a portion of the working electrode is within a distance of no more than 200 m of a portion of the counter electrode; a measurement zone positioned adjacent to the working electrode and counter electrode, wherein the measurement zone is sized to contain a volume of no more than about 1 &mgr;L of sample; a reference electrode disposed in contact with the measurement zone; and an analyte-responsive enzyme and a diffusible redox mediator disposed in the measurement zone; wherein the sensor is configured and arranged so that the redox mediator oxidizes the analyte and the half-wave potential of the redox mediator, as measured by cyclic voltammetry in 0.1 M NaCl at pH 7, is no more than about +100 millivolts relative to the potential of the reference electrode.