Abstract: The invention relates to reference electrodes for use in voltammetric measuring chains for oxidative as well as reductive detection of analytes, which are open with respect to the measuring medium. A metal-containing phthalocyanine or a metalloporphyrin is employed as potential-determining electrode material for reference electrodes of the invention used in oxidative detection. A fourth period metal, preferably copper, and a salt of said metal is employed as potential-determining electrode material for reference electrodes of the invention used in reductive detection. The potential-determining electrode material is coated as a layer or component of a layer on a planar support. The open reference electrodes according to the invention are particularly suited for voltammetric chemo- or biosensors having a planar structure.

Abstract: The invention relates to an enzymatic-electrochemical affinity sensor and a one-step affinity assay for the quantitative determination of analytes in aqueous media. More specifically, the invention relates to an enzymatic-electrochemical signal amplification system for a highly sensitive indication of affinity reactions and is particularly suitable in the form of a one-step affinity sensor for in situ analytics. The invention is also directed to the use of phenol oxidase as a marker enzyme for the affine binding partners in an electrochemical affinity sensor or assay, and to the use of an enzyme hydrolyzing phenolic compounds as marker enzyme for the affine binding partners, in combination with a phenol oxidase as catalyst for the amplifying reaction in an electrochemical affinity assay.