| 摘要 |
PURPOSE:To enable the measurement of the amount of uric acid with a simple equipment, by injecting uric acid into a first electrode having uricase immobilized thereon and a second electrode having none to determine the oxidation current value of hydrogen peroxide formed. CONSTITUTION:A constant voltage B is applied to working poles of a first electrode 4 having uricase immobilized thereon and a second electrode 5 having none, a solvent 6 is passed through a tube 7 with a pump 2 at a constant speed and a sample is injected from a sample injection port 4. Changes in the current of the working pole and an opposed pole of the electrode 4 are given as the sum of the oxidation current of hydrogen peroxide and the oxidation current of uric acid with the action of the uricase and current changes between the working pole and the opposed pole of the electrode 5 is given as oxidation current of uric acid. After a reducing substance is injected beforehand, the detection sensitivity ratio of both the electrodes 4 and 5 are used to calibrate the measured current values of both the electrodes. The oxidation current of hydrogen peroxide due to the enzyme reaction or uricase is determined from the output current difference of both the electrodes. Since the current value depends on the concentration of uric acid in a sample liquid, the concentration of uric acid in the sample liquid can be defined by preparing a calibration curve about uric acid with the known concentration. |
