INDIRECT PHOTOMETRIC CHROMATOGRAPHY OF ANIONS USING SODIUM NAPHTHALENETRISULFONATE

A triply charged eluent has been characterized for anion-exchange chromatography with indirect photometric detection. Sodium naphthalenetrisulfonate has shown particular promise for the separation and detection of NO2-, Br-, No3-, SO4(2-), I-, and SCN-. The analysis of a mixture containing these anions can be performed in less than 18 min with detection limits of 0.4-1 ng for all anions. The determination of the strongly retained sulfur oxides such as dithionite, tetrathionate, and other polythionates can be easily accomplished with this highly charged eluent in a short time with high sensitivity. The chromatographic performance of this eluent requires no pH adjustment of the mobile phase. In addition, chromatograms obtained with this eluent were free from any system peaks.