Abstract: A measuring device for the detection and determination of the concentration of at least one analyte in a liquid medium consists of a polymeric carrier having biologically active specific binding molecules dried on its upstream portion. A multiple electrode set consisting of at least one reference electrode and at least one working electrode is located thereon in a downstream region. The working electrode is provided with biologically active specific binding molecules. The carrier has a sample application zone, which is adjoined, in the downstream direction, by a non-deformable, through-flow reaction and detection chamber, a variably dimensioned interstice, and a liquid absorption element. For a qualitative and quantitative analyte determination, two liquid media are applied in succession to the sample application zone. While the first can contain the wanted analyte, the second provides for the formation of an electrical signal.