Chemiluminescence flow injection analysis of 1,3-dichloro-5,5-dimethylhydantoin in swimming pool water

A new chemiluminescence (CL) flow-injection method is proposed for the determination of 1,3-dichloro-5,5-dimethylhydantoin (DDH). The method is based on the chemiluminescent reaction of DDH and luminol–H2O2 in an alkaline medium (pH 12.0–12.5). The concentration of the analyte shows a good linear relationship with the produced luminescence intensity in the range of 3.0×10−8 to 8.0×10−6 mol l−1. The detection limit of the proposed method is 1.0×10−8 mol l−1 and the relative standard deviation (R.S.D.) is 4.7% (n=5) at 5.0×10−7 mol l−1. This method was successfully applied to the determination of trace amounts of this disinfectant in water samples obtained from five different swimming pools. Satisfying recovery values were also obtained.