Two or more electrodes (16, 18, 20) are parallel wire electrodes with circumferential electrode surfaces. They run along a profiled insulator (32) with partitions for the electrodes. The insulator is Y-shaped, X- shaped or star-shaped in cross section. The working electrode (16) is surrounded by a reagent medium, especially a bodily tissue and/or fluid, to determine the concentration of an analyte. The electrodes may be covered individually or collectively as an electrode pack, by a layer of immobilizing medium. An independent claim is included for the method of making the sensor.
