Study of hypochlorite-specific enhancement in ICP-AES and ICP-MS

Severe chlorine signal enhancement in ICP-AES (by a factor of 2.6 to 3) and ICP-MS (by a factor of about 2) was found in the determination of Cl in hypochlorite (ClO−) but not in the determination of Cl in four other chlorine-containing species (Cl−, ClO2−, ClO3−, and ClO4−). A near linear correlation between the extent of the enhancement and the hypochlorite concentration was established, and the enhancement can only be removed by converting hypochlorite into other chlorine-containing species.