Fluorometric determinations of nitrite and amyl nitrite with 2,3-diaminonaphthalene

Fluorometric determination of nitrite with 2, 3-diaminonaphthalene (DAN) has been investigated. By removing some of the impurity contained in DAN, the sensitivity of the analytical conditions (concentration of reagent, reaction time and temperature) were extended over that of the conventional methods. Nitrite was determined in the range of 22000 ng. The relative standard deviation (R.S.D.) was 0.7% (n= 5) at 100 ng of nitrite. The presence of thiosulfate and ascorbic acid interfered. This method was also applied to the determination of amyl nitrite. Amyl nitrite was first dissolved in glacial acetic acid and was then diluted with water. The solution was analyzed in a similar manner as nitrite. Amyl nitrite was determined in the range of 0.0220μg. The R.S.D. was 1.1 % (n=10) at 2μg of amyl nitrite.