Flow-injection chemiluminescence determination of chlorinated isocyanuric acids

A rapid and sensitive flow-injection chemiluminescence method is described for the determination of dichloro- and trichloroisocyanuric acids based on the chemiluminescence produced during their reaction with luminol in alkaline medium. The effects of analytical and flow-injection variables on these chemiluminescence systems and determination of both oxidants are discussed. The optimized method yielded 3sigma detection limits of 8x10(-8) and 5x10(-8) mol L-1 for the sodium dichloroisocyanurate and trichloroisocyanuric acid, respectively. The optimum conditions were found to be as follows: NaOH, 1 x 10(-1) mol L-1; luminol, 5x10(-3) mol L-1; KI, 2x10(-3) mol L-1 and flow rate, 3.5 mL min(-1).