1,1'-OXALYLDIIMIDAZOLE AS CHEMILUMINESCENCE REAGENT IN THE DETERMINATION OF LOW HYDROGEN-PEROXIDE CONCENTRATIONS BY FLOW-INJECTION ANALYSIS

The reaction between the chemiluminescent compound 1,1'-oxalyldiimidazole (ODI) and hydrogen peroxide was studied. The flow system was simplified by the use of an immobilized fluorophore (3-aminofluoranthene) on an acrylate polymer. The chemiluminescent intensities were compared with those obtained by the well-known reaction between trichlorophenyl oxalate (TCPO) and hydrogen peroxide (catalyzed by imidazole). The results show that ODI is about 10 times more sensitive than TCPO. When these compounds were compared in a static system, their different kinetics were quite obvious. The total amount of light produced is equal, but the ODI reaction is faster compared to the TCPO reaction. The estimated detection limit for H2O2 in water was 1 x 10(-8) M (0.5 pmol injected).