CONTINUOUS-FLOW ASSAY OF AMMONIA IN PLASMA USING IMMOBILIZED ENZYMES

A simple, convenient and rapid enzymatic method for the determination of ammonia in plasma based on the immobilization of glutamate dehydrog enase and on a continuous flow system is proposed. The fixed-time meas uring principle allows shortening of the assay time without loss of se nsitivity, so a sampling frequency of 40 h(-1) can be achieved in a li near range of 5-500 mu M with a coefficient of variation of less than 2%. The method correlates well with the results of the Kodak Ektachem analyzer and can also successfully be compared with other automated ba tch methods which it surpasses in rapidity, simplicity and lower cost of the assay.