Patent ID: 8480878

Claim:
A biosensor for quantifying a substrate in a sample liquid comprising: an insulating support; a working electrode formed from an electrically conductive layer that is made of a noble metal and is provided on a surface of the insulating support; a reagent layer on the working electrode; a spacer layer provided on and covering part of the reagent layer, where the spacer layer defines a supply path for bringing the sample liquid into contact with the reagent layer and where the supply path formed by the spacer layer is narrower than the reagent layer; and a cover provided on the spacer layer, where the cover comprises a counter electrode formed from an electrically conductive layer that is made of a noble metal and is provided on an inner surface of the cover; wherein a portion of the counter electrode and a portion of the working electrode are in the supply path, and wherein part of the reagent layer is in the supply path.