ELECTROCHEMICAL SENSOR CAPABLE OF DETERMINING HYDROGEN PEROXIDE CONCENTRATION AND ANALYZER USING THE SAME

摘要

A urea-determining sensor and a glucose-determining sensor are arranged to face a single passage through which a sample flows. The urea sensor combines a membrane of immobilized urease with an ammonium ion-selective electrode. The glucose sensor consists of a layer of immobilized glucose oxidase and a polarographic electrode having a hydrogen peroxide-permeable layer. The latter sensor incorporates a work electrode and a counter electrode, and determines the concentration of hydrogen peroxide that permeates therethrough from the intensity of electric current that flows between the two electrodes. The counter electrode of the glucose sensor is formed of metallic palladium. The specific counter electrode material eliminates the problem of silver dissolution into the flow passage and extends the life of the urea sensor.