Chemiluminescence flow sensor for the monitoring of hydrogen peroxide in rainwater

A novel chemiluminescence(CL) sensor has been developed for determining hydrogen peroxide in rainwater. The analytical reagents involved in the CL reaction, including luminol and copper ion. were immobilized on anion exchange resin and cation exchange resin, respectively. While a volume of sodium sulphate was passed through a column with immobilized reagents, these two reagents were eluted from the resins and then reacted with hydrogen peroxide in alkaline aqueous solution to produce CL. The CL emission intensity was correlated with the hydrogen peroxide concentration in the range 8 x 10(-8) to 1 x 10(-4) M, and the detection limit was 3.5 x 10(-8) M hydrogen peroxide. Interfering ions present in rainwater were effectively separated on-line by an upstream ion exchanger. A complete analysis, including sampling and washing, could be performed in 1 min with a relative standard deviation of less than 5%. The system was stable for over 200 analyses and has been applied successfully to the determination of hydrogen peroxide in rainwater samples.