JPS56155846A - Method and device for measuring ion concentration - Google Patents

Abstract

PURPOSE:To measure the ions in a small amount of specimen liquid such as blood with good responsiveness by inserting reference electrodes into the respective chambers of a measuring cell segmented to a reference soln. chamber and a specimen soln. chamber via an ion selective membrane, and providing an interelectrode potential difference measuring system. CONSTITUTION:A selective membrane 2 for the ions to be measured is provided between a reference soln. chamber 4 and a specimen soln. chamber 5, and respective soln. lead-in tubes 6, 7 and discharge tubes 8, 9 are provided to the respective chambers 4, 5. The reference electrodes 12, 13 of the same kind are inserted into the chambers 4, 5, and the electrode 12 is connected to a recording mechanism 15 for high input impedance potential difference by way of a potentiometer 14, and the electrode 13 directly thereto. The measurement is accomplished by putting a reference soln. in both chambers 4, 5, and controlling potential difference of the electrodes 12, 13 zero. Thence, the reference soln. of the chamber 5 is discharged by moving a 3-way cock 10, and after the lead-in tube 7, the chamber 5 and the electrode 13 are washed with pure water, the specimen liquid is put into the chamber 5 through the tube 7. The potential difference between the electrodes 12 and 13 is measured, recorded and displayed. In this way, the ions in said liquid are measured accurately in a less response time than that by a conventional method of using ion selective electrodes and without the need for prior making of a calibration curve.