Flow-Injection Analysis with Chemiluminescence Detection of Glucose and Uric Acid Using Immobilized Enzyme Reactor

Abstract

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-tetrathiomor-pholinopyrimido[5,4-d]pyrimidine, was monitored. Linear responses between the concentration and the CL intensity for glucose and uric acid were obtained up to 3×10^-4 M (6 nmol per 20 μl injection, r=0.999) and 1×10^-5 M (0.2 nmol per 20 μl injection, r=1.000), respectively; both limits of detection were the same (5×10^-7 M, 10 pmol per 20 μl injection, S/N>3). The relative standard deviations for ten replicate measurements were 1.1% for glucose (2×10^-5 M, 0.4 nmol/ injection) and 2.2% for uric acid (5×10^-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.