| 摘要 |
PURPOSE:To carry a sensor unit while preventing an oxide film, etc., from being formed by incorporating a backup power source part in the sensor unit. CONSTITUTION:Electrodes 5 and 6 are provided on the projecting surface of a unit main body 4 and connection terminals 7 and 8 are provided on the other side. Further, the backup power source part 9 is provided between the electrodes 5 and 6 and a fixed enzyme film 10 is provided covering the projecting surface. Then an operating voltage is applied in measuring operation so as to place the diode 12 of the power source part 9 in a reverse bias state, and then the influence of a backup battery 11 is eliminated. In this state, a solution to be measured is brought into contact with the film 10 and then enzyme reaction is caused to produce or eliminate a specific substance, thereby generating an electric signal corresponding to the amount of the substance. This signal is supplied to a measuring instrument main body through terminal 7 and 8 to generate a signal showing the concentration, etc., of the object substance. When the measuring operation is not performed, an oxide film is prevented from being formed on the electrode surface owing to the application of the backup voltage of the power source part 9, thereby preventing characteristics from deteriorating. |
