Abstract: A device for performing electrochemical and/or optical measurements in fluids, includes a sensor part of substantially planar configuration carrying a plurality of sensors that are connected to conductive paths; a cover part, which includes a groove-shaped measuring channel through which the fluid will flow; and a sealing element positioned between the sensor part and the cover part for sealing the measuring channel. The cover part includes grooves which extend in parallel with the measuring channel and which define respective ridges between the grooves and the measuring channel, and the sealing element substantially includes guiding bodies which are retained in the grooves of the cover part and are provided with integrally molded narrow sealing lips protruding in the area of the ridge. The sensor part and the cover part are joined by a plurality of locking elements which are distributed along the measuring channel.

Abstract: A planar sensor for determining a chemical parameter of a sample, includes a substrate whose surface is at least partly plane and is provided with at least one potentiometric or amperometric and, possibly, an optical transducer, and one or more biochemical components. The transducer and the biochemical component are provided on the surface of the substrate, or at least part of the surface, as a sensor spot, and a cover membrane surrounding this sensor spot, is heat welded to the surface of the substrate. Those sensor spots that include a potentiometric or amperometric transducer are in contact with a strip conductor attached to the plane surface of the substrate and the thermal seal of the cover membrane is interrupted where the conducting strips lead away from the sensor spots.