QUANTITATIVE DETERMINATION OF UREA NITROGEN AND CREATININE

摘要

PURPOSE:To determine quantitatively and quickly urea and creatinine in one conductivity cell by adding successively creatinine deiminase and urease to a liquid to be inspected, detecting the change quantity of the conductivity in each stage and calculating the difference thereof. CONSTITUTION:A platinum electrode 1 is provided to a measuring cell 4. A sample liquid and buffer soln. are put into the cell 4 through a feed port 6. The liquid to be inspected and creatinine deiminase soln. are first injected into the cell and the conductivity by the NH<+>4 formed by enzyme reaction is measured by a measuring instrument 11, by which the creatinine is determined and the change quantity X of the conductivity thereof is calculated. The urease soln. is then put into the cell and the change quantity of the conductivity by the formed NH<+>4 and HCO<->3 is detected. The urea nitrogen is determined by subtracting the quantity X from the quantity Y. The two different enzyme reactions are continuously effected in one conductivity cell and the change quantity of the conductivity is detected and calculated and therefore the quick analysis of the creatinine and urea nitrogen by a simple measuring method is made possible.