FLOW-INJECTION ANALYSIS WITH CHEMILUMINESCENCE DETECTION OF GLUCOSE AND URIC-ACID USING IMMOBILIZED ENZYME REACTOR

A rapid and sensitive flow-injection method with peroxyoxalate chemiluminescence (CL) detection for the determination of glucose and uric acid by using an immobilized enzyme reactor is described. CL produced in a flow cell by the reaction of hydrogen peroxide with bis(2,4,6-trichlorophenyl)oxalate and a fluorescent compound, 2,4,6,8-tetrathiomorpholinopyrimido[5,4-d]pyrimidine, was monitored. Linear responses between the concentration and the CL intensity for glucose and uric acid were obtained up to 3 x 10(-4) M (6 nmol per 20-mu-l injection, r = 0.999) and 1 x 10(-5) M (0.2 nmol per 20-mu-l injection, r = 1.000), respectively; both limits of detection were the same (5 x 10(-7) M, 10 pmol per 20-mu-l injection, S/N > 3). The relative standard deviations for ten replicate measurements were 1.1% for glucose (2 x 10(-5) M, 0.4 nmol/injection) and 2.2% for uric acid (5 x 10(-6) M, 0.1 nmol/injection). Good correlations between the results of serum glucose or uric acid assay by the proposed methods and by the conventional colorimetric methods (r = 0.994 for glucose and r = 0.986 for uric acid) were obtained.