Fluorimetric nitrite analysis using 2,3-diaminonaphthalene: an improvementof the method

One of the fluorimetric methods for nitrite determination is based on the r eaction of nitrite ions with 2,3-diaminonaphthalene (DAN) to form fluoresce nt 1-[H]-naphthotriazole. The procedure is sensitive, simple and rapid. How ever, the DAN reagent is carcinogenic and its use in a large excess for the reaction might be a drawback for an extensive application. In particular t o know ii a stoechiometric quantity of the reagent might be sufficient to r un the reaction, the method was re-examined. In fact, using the latter cond ition, it was still possible to get nitrite determination in the range 0 to 50 mu g NO2-.L-1, with a rather smaller analysis time.