Gas-gap sensors for the determination of nitrogen oxides and nitrites Original Research Article

Two new air-gap sensors with different indicator electrodes for the determination of nitrogen oxides and nitrites are described. The linear range of the electrode functions E = f(−lg[NO2]) and E = f(−lg[NaNO2]) for the sensor on the base of a combined glass pH electrode was 5 × 10−8–1 × 10−3 M, and on the base of combined NO3−–ion-selective electrode it was 5 × 10−6–1 × 10−3 M. The calibration curve slopes were 58.5 mV in both cases. The designed sensors were used for nitrite determination in some environmental samples.