New electrochemical sensors for detection of nitrites and nitrates.

Pt electrodes modified with a cellulose acetate membrane or with poly(1,8-diaminonaphthalene) film were assembled and used for rapid amperometric detection of nitrite and nitrate in water by batch and flow injection anal. Parameters such as the permeability of the electropolymd. films to nitrite and nitrate, interference effects, and recovery studies of these kinds of sensors were optimized to demonstrate the anal. suitability of the proposed method. Contrary to the std. colorimetric method, which is based on carcinogenic reagents, the amperometric detection of nitrite and nitrate is very simple and rapid and does not require any reagent for nitrite detection. Also, this method could be extended easily to the anal. of nitrite and nitrate in various types of samples such as food, soils, vegetables, and fertilizers.