Highly sensitive determination of carbon dioxide withH(2)O(2)-luminol-uranine-K2CO3 Chemiluminescent reaction

The chemiluminescent (CL) reaction for the oxidation of luminol with hydrogen peroxide in an alkaline medium was greatly affected by the presence of carbonate. The intensity of CL reaction was evidently enhanced by the addition of uranine. Based on this, a novel CL method for the determination of carbon dioxide was established. The method provided the detection a wide linear concentration rang from 1.0 X 10(-10) to 5.0 X 10(-6) mol.L-1 and a low detection limit of 1.2 X 10(-1)1 mol.L-1 carbonate or 5.3 X 10(-10) g.L-1 carbon dioxide. It has been applied to determination of carbon dioxide in indoor and outdoor air with relative standard deviations (RSD) of 1.8%similar to 2.1% (n=11). The recoveries of the spiked samples were 97.6%similar to 101.4%. A reasonable mechanism was also proposed. The CL reaction is probably triggered by the interaction of H2O2-K2CO3 and then enhanced by uranine via chemical energy transfer from luminol to uranine