Polarographic determination of atmospheric nitrogen oxides.

A new polarographic method is described for the determination of nitrite/nitrogen oxides. The nitrite is first diazotized with p-aminobenzoic acid, followed by coupling to 8-hydroxyquinoline to produce an azo dye. This azo dye is adsorbable on a mercury drop electrode and its reduction is reversible. The linear response range is 6 x 10(-9)-3 x 10(-7) g/ml. The detection limit is 4 x 10(-9) g/ml. This method has been applied to the determination of nitrogen oxides in the air.