Determination of Trace Amount of Cd (II) in Water by Chemiluminesce Assay

Inhibitory function of luminol-Co(II)-H2O2 chemiluminescence by Cd(II) was studied in this research using static- state-injection chemiluminescence, and it was applied to determine Cd(II) in water. The results indicated that Co(II) enhanced the chemiluminescence intensity of luminol-H2O2 , while Cd(II) restrained the chemiluminescence intensity of luminol-Co(II)- H2O2. Further research indicated that the restraint of luminol-Co(Ⅱ)-H2O2 chemiluminescence by Cd(II) had a relationship with the concentration of Cd(II) in water. The linear range is 1.0 × 10-7～5.0 × 10-6 g/ml. The limit of detection is 3.2 × 10-8 g/ml. The method was applied to the determination of Cd(II) in water and satisfactory result was obtained. Meanwhile, the possible reaction mechanism was put forward based on the further study.