Simple Analysis for Inorganic Anions in Air Samples by Means of Capillary Electrophoresis

Nonmetallic components in the air were determined by capillary electrophoresis as Cl-, NO2, NO3-, SO42- and F- in condensed water of moisture in the air, collected by a dehumidifier. Indirect absorbance detection of anions was accomplished with a mixed solution of 2 mmol/l ammonium molybdate-1.5 mmol/l diethylenetriamine at pH 8.5 in capillary electrophoresis. More than 5 anions in condensed water were detected at the ppm level without concentration. The sampling time of condensed water necessary for the analysis was several minutes, and the migration time for the separation of 5 anions was within 8 minutes. This method can be applied to monitor nonmetallic components in the air in a flow system.