Patent ID: 6793802
Filing Date: 2004-09-21
Classification: C12Q

Abstract:
A biosensor for electrochemical analysis of a liquid sample, which biosensor comprises:a) an insulating base plate having a first end and a second end; b) an electrode system on said insulating base plate, wherein said electrode system comprises a working electrode and a counter electrode, said working and counter electrodes have conductive leads for connecting said electrodes to a readout device for electrochemical measurement on said first end of said base plate, said working electrode is engulfed by said counter electrode on all sides except the side leading to said conductive leads, and there is a gap space between said working and counter electrodes; c) a reaction area as part of said electrode system, said reaction area occupies at least a portion of said working electrode, said counter electrode and the gap space between said working electrode and said counter electrode in a direction perpendicular to said conductive leads, said reaction area is defined by covering a non-reaction-area with a layer comprising a dielectrical material, and said reaction area comprises an enzyme that catalyzes a reaction involving an analyte to be analyzed or a substrate that is involved in a reaction catalyzed by an enzyme to be analyzed; and d) a sample application and reaction chamber, wherein the bottom of said chamber is said reaction area defined in c), the top of said chamber is a cover that covers at least said reaction area, said top has an opening above said reaction area for sample application, two side walls of said chamber in a direction perpendicular to said conductive leads are formed by said layer comprising said dielectrical material defined in c), and two sides of said chamber in a direction parallel to said conductive leads are left open as air vents.