Gastroscope i.e. flexible endoscope, for examining e.g. gastric acid, on upper gastrointestinal tract for Helicobacter pylori of patient, has sensor with electrodes, where change in electric variable is measured between electrodes

摘要

The gastroscope (1) has an insertion tube (2) in which a working channel (3) is arranged, and a sensor (4) guided in the working channel via a guide wire (5). The sensor has an electrode (6) made of an acid-fast noble metal, and another electrode (7) made of silver. An electrical voltage is applied between the electrodes and a change in an electric variable e.g. electrical current or electric resistance, is measured between the electrodes when ammonia is present. The former electrode is made of platinum or gold, and the latter electrode is made of silver chloride layer.