Sensitized determination of sulfite using flow injection with chemiluminescent detection

The acidic oxidation of sulfite by CeIV is weakly chemiluminescent. A comparative study of the chemiluminescent determination of sulfite with the use of 3-cyclohexylaminopropanesulfonic acid (CAPS) and of cyclooctylamine as sensitizers of the reaction was made using a flow injection procedure. Despite a slight decrease in sensitivity, it was found that cyclooctylamine was superior to CAPS as a sensitizer and a detection limit of 5.4 × 10–7 mol l–1 sulfite was achieved compared with 1 × 10–5 mol l–1 using CAPS.